As we know bacteria is everywhere, both the good ones and the not so good ones. Sometimes the bad ones can get a little out of hand and start causing a whole host of problems, we know this as bacterial overgrowth and we’re going to be looking at small intestinal bacterial overgrowth, or SIBO specifically. Here at My Pet Nutritionist is something we keep an eye out for, so we thought we’d let you know why. Small intestinal bacterial overgrowth (SIBO) is defined as excessive bacteria in the small intestine. SIBO is frequently implicated as the cause of chronic diarrhoea and malabsorption. Dogs with SIBO may suffer from unintentional weight loss, nutritional deficiencies, and osteoporosis for example. When we reference the microbiome, we are considering the microbial community found in the whole of the digestive tract. Generally, the further down we go, the more bugs we find. So, we would expect the majority of the bugs to be found in the colon. SIBO is when there are higher numbers found in the small intestine. The type of microbial flora present plays an important role in the manifestation of signs and symptoms of overgrowth. For example, a predominance of bacteria that metabolize bile salts to unconjugated or insoluble compounds may lead to fat malabsorption or bile acid diarrhoea. In contrast, microorganisms that preferentially metabolize carbohydrates to short-chain fatty acids and gas may produce bloating without diarrhoea because the metabolic products can be absorbed. There are a number of contributing factors to the development of SIBO but two of the main ones are gastric acid secretion and small intestine dysmotility. Gastric Acid Gastric acid is necessary in the digestion of food. Not only that but it suppresses the growth of ingested bacteria (it forms one of the protective barriers), which limits bacterial counts in the upper small intestine. Gastric acid is produced in the stomach, so it provides a buffer before compounds even reach the small intestine. Gastric acid is produced by the parietal cells in the stomach, and there are cases of autoimmunity whereby the body attacks its own parietal cells resulting in low levels of gastric acid. Not only that but certain medications like proton pump inhibitors are also used to suppress gastric acid. Antihistamine medications also suppress gastric acid secretion. PPIs are often used to treat a range of GI disorders in dogs and antihistamines are regularly used to treat allergic dermatitis. In addition, gastric acid secretion is regulated by the parasympathetic nervous system via the vagus nerve and there is clear evidence that increased levels of certain stress hormones inhibits the release of it. Can Stress Affect My Dog’s Digestive System The stress response also plays a role in intestinal motility. Intestinal Motility Several programmed movements are responsible for the transport of food between the different parts of the digestive system. Peristalsis is a series of wave-like muscle contractions that move food through the digestive tract. The migrating motor complex typically moves between the stomach and small intestine, sweeping the intestine clean between meals; this is the rumble you will hear! Hormones like motilin and ghrelin are involved in the generation of MMCs. Mass movement is another programmed movement, and this is what propels the formed poop into the rectum, ready for evacuation. Mass movements are put on hold overnight but start again in the morning. They follow their own circadian rhythm. Impaired gastric motility can result in food and waste sitting in the small intestine for longer that it should. There are a number of reasons why motility may be affected. Mechanical obstruction, Abnormalities in smooth muscle function, Secondary conditions such as electrolyte disturbances, metabolic disorders, concurrent medication use, stress, and abdominal inflammation. However, there is more attention being paid to the development of SIBO through antigens gaining access to the lamina propria. The lamina propria is a thin layer of connective tissue that forms part of the moist linings known as mucous membranes or mucosa which line the respiratory and gastrointestinal tract. It is therefore thought that a compromised mucosal barrier is a risk factor for SIBO. The mucus layer is the very first line of physical defence that external molecules encounter when they arrive in the gut lumen, it prevents bacteria from directly contacting the epithelial cells, along with toxic substances and digestive enzymes. Within this strand, it therefore prevents colonic inflammation. The main building blocks of the mucus layer are highly glycosylated mucin proteins that form a gel-like sieve structure overlying the intestinal epithelium. The small intestine only has one mucus gel layer whereas the colon has two layers: an outer, loose layer that allows the long-term colonisation of commensal bacteria, and an inner dense layer empty of bacteria. Mucin degradation has been recognized as a normal process of mucus turn-over in the GI tract, but selective bacterial species can degrade mucous glycans as an energy source in the absence of other food sources and so if degradation outperforms secretion, we start to have a problem. Furthermore, diets high in refined products, sugars and saturated fats are also associated with compromised mucosal function. Early stress is also linked to impaired mucosal development, so the health of our puppy’s gut really does start with the Mother! Prevalence of SIBO SIBO has also been noted in dogs with existing chronic intestinal disease, and although many breeds are affected, German Shepherds are seemingly predominant in reports. SIBO is regularly seen in dogs with exocrine pancreatic sufficiency. Juice culture is the gold standard for SIBO diagnosis, but it is often described as being technically difficult, time-consuming and expensive. In addition, bacterial counts may be influenced by environmental factors and infective load. One of the first things to consider is whether your dog is currently eating an antigenic diet – with the increased intestinal permeability that often accompanies SIBO, establishing sensitivities is a good place to start. Elimination Diets For Dogs In addition to this, if SIBO has been prolonged there may be underlying nutrient deficiencies so
A question that often pops up here at My Pet Nutritionist so we thought we’d do a whistle stop tour on the gallbladder and some of the more common issues that can arise when it’s not functioning as it should. Let’s get cracking. The gallbladder is a pear-shaped organ that sits just under the liver. Its function is to store and concentrate bile, a yellow-brown digestive juice produced by the liver. It is part of the biliary tract. When food enters the small intestine, a hormone known as cholecystokinin is released, this tells the gallbladder to contract and secrete bile into the small intestine, through the common bile duct. There are two important functions of bile: Bile contains bile acids, which are critical for digestion and absorption of fats and fat-soluble vitamins in the small intestine. Many waste products, including bilirubin, are eliminated from the body by secretion into bile and elimination in faeces. Bile contains water, electrolytes and a battery of organic molecules including bile acids, cholesterol, phospholipids and bilirubin. Sadly, the build up of these very compounds can lead to a number of problems in the gallbladder, they are known as canine gallbladder diseases and include: Biliary Sludge Gallbladder mucoceles Gallstones Gut Guardian Biliary Sludge Gallbladder sludge is a collection of cholesterol, calcium, bilirubin, and other compounds that build up in the gallbladder. It is more technically known as biliary sludge. It is not technically a condition on its own, but it’s presence can lead to further issues. Gallbladder sludge has been associated with: Obesity Rapid weight loss Cholecystitis – the swelling and inflammation of the gallbladder. It can result in bile trapped in the gallbladder, causing pain, vomiting, and bloating Blocked biliary ducts – these allow the gallbladder to drain – if sludge can’t escape, it accumulates Of interest, biliary sludge has been associated with acute cases of pancreatitis. In human cases, where no cause of pancreatitis could be found, upwards of 30% of patients showed evidence of biliary sludge. Findings Here If the initial cause of gallbladder sludge is rectified, then it often resolves on its own. However, if the factors remain, gallbladder sludge can lead to gallstones. Gallstones Gallstones are not surprisingly, small stones that form in the gallbladder. It’s when there is an imbalance in the usual liquid composition of bile inside. Because inadequate emptying or infrequent gallbladder movement are usual factors that increase the likelihood of gallstones forming, it’s easy to see how biliary sludge can lead to gallstones. Risk Factors for gallstones; Obesity, Older age, Disorders of the digestive system, Rapid weight loss, Signs and Symptoms of gallstones: Vomiting Jaundice Loss of appetite Abdominal pain Fever Discomfort after eating Gallstones are more commonly seen in older dogs, and often in smaller breeds like miniature schnauzers and miniature poodles. They may be identified in the gallbladder, common bile ducts, hepatic, or interlobular ducts. They are generally composed of cholesterol, bile pigments and calcium carbonate. Gallbladder mucoceles (GBM) A gallbladder mucocele is an abnormal accumulation of bile laden mucoid material within the gallbladder, resulting in bile duct obstruction. Mucins, which play a major role in the development of gallbladder mucoceles, are a family of polysaccharides secreted by mucosal epithelial cells of the gallbladder, stomach, intestines and other organs. Mucins act as surfactants and play a mucoprotective role by preventing self-digestion of mucosal epithelium by digestive juices. A gallbladder mucocele is characterized by the excessive secretion of mucin from gallbladder epithelium. Dogs who have suffered with GBM have ranged in age from 3-14 years old, but middle to older aged dogs are thought to be at a higher risk. A genetic mutation has also been found on the ABCB4 (MDR3) phospholipase flippase transported in Shetland Sheepdogs and others. There is an increased incidence in these dogs along with Miniature Schnauzers and Cocker Spaniels. Findings Here Signs and Symptoms of GBM: Loss of appetite Lethargy Vomiting Diarrhoea Jaundice Abdominal pain or discomfort The underlying cause of GBM is essentially unknown, but there are considered associations. For example, gallbladder mucoceles has been associated metabolic disruption. Dogs with GBM: are characterized by significantly diminished antioxidant capacity demonstrate altered energy metabolism have abnormal lipid metabolism demonstrate presence of xenobiotics compared to controls In addition, those dogs with GBM formation show increases in certain compounds that suggest they are in a state of excess metabolic energy. This is why these dogs show lower levels of pantothenate, riboflavin and nicotinamide riboside because there is an increased demand for these compounds in energy transportation. Findings Here There is also consideration given to hydration state; studies have indicated an underlying defect in electrolyte, acid-base or fluid transport. Findings Here Finally, the formation of gallbladder mucoceles has been associated with certain medication use: Dogs with GBM were 2.2 times as likely to have had reported use of thyroxine 3.6 times as likely to have had reported treatment for Cushing’s disease 2.3 times as likely to have had reported use of products containing imidacloprid (insecticide) Findings Here Supporting Healthy Gallbladder Function Maintain an ideal body score Obesity in Pets – Part One Obesity in Pets – Part Two Support digestive function Low Fat Kangaroo The Dog’s Digestive System Optimal Gut Health Pancreatitis: Natural Guide for Pets Stay hydrated! Offer filtered water and ditch the dry! Offer antioxidant rich foods! Berries and leafy greens are a great place to start! Dietary Patterns Studies have indicated that the consumption of sugar, refined grains, processed meats and low-fat food products are associated with increased risk of gallstone disease. Likewise, the intake of nuts, fruits, vegetables and omega-3 PUFAs is associated with reduced gallstone disease. Supportive nutrients in terms of gallbladder health include fibre, magnesium, and vitamin C. Findings Here Why Is Magnesium So Important to Your Pet Why Fibre is Good For Your Dog Why Chia Is So Good For Your Dog Issues with the gallbladder are sadly not that simple, there are several factors to consider. If you are concerned about your dog’s gallbladder or liver
Histamine intolerance (HIT), more technically known as enteral histaminosis, is characterised by the development of problematic symptoms after the ingestion of histamine containing foods. However, current schools of thought are that HIT is not solely due to dietary histamine exposure, but exposure along with insufficient or impaired histamine detoxification. We can see the raised eyebrows from here, so here at My Pet Nutritionist, we thought we’d take a closer look at this issue. What is histamine Histamine is a transmitter in the nervous system and a signalling molecule in the gut, skin, and immune system. It is synthesised from the amino acid histidine which is in fact an essential amino acid for humans and dogs. It is primarily associated with the functioning of the immune system. During an immune reaction, histamine is released from mast cells throughout the body and contributes to the physical changes necessary for the immune system to fight the pathogen, like the increase in blood pressure, temperature, swelling, and constriction in the lungs. Histamine is released to carry out a function and then it is removed, or it should be, efficiently. Detoxification of dietary histamine normally occurs in intestinal epithelial cells via the enzyme diamine oxidase (DAO) as well as histamine-N-methyl-transferase (HNMT) in the liver. The term histamine intolerance is used similarly to lactose intolerance in humans (LIT). LIT, with a deficiency of the enzyme lactase, shows parallels to the definition of HIT, with a deficiency of the GI enzyme diamine oxidase (DAO). DAO is a secretory protein stored in structures of the plasma membrane and is responsible for the degradation of extracellular histamine. The expression of DAO is restricted to certain tissues, mainly the small intestine, colon, placenta and kidneys. In the intestine, DAO activity increases progressively from the duodenum to the ileum and is located mainly in the intestinal villi. On the other hand, the enzyme HNMT is expressed in a wide range tissues including the kidneys and liver, the spleen, colon, prostate, ovaries, spinal cord cells, trachea, and respiratory tract. The gateway for dietary histamine is the intestinal epithelium. So, although HNMT is also present in the gastrointestinal tract, the more highly expressed DAO plays the major role in protecting the body against exogenous histamine, whether originating from ingested food or generated by the intestinal microbiota. What Can Cause Deficiencies in DAO? There are polymorphisms in the genes that encode for the DAO enzyme, but certain medications, including over the counter products are seen to inhibit the activity of DAO enzyme too. They include: Analgesics – morphine, NSAIDs Antiarrhythmics Antibiotics Antifungals Antimalarial Diuretics Motility agents Muscle relaxants Vitamins – ascorbic acid, thiamine Findings Here Furthermore, several inflammatory bowel pathologies affecting mucosal integrity are known to result in impaired DAO activity. DAO activity has been proposed as a marker of the integrity of intestinal mucosa. In inflammatory bowel diseases, reduced DAO activity was related to the degree of mucosal damage. In one human study, DAO activity was significantly reduced in cases of ulcerative colitis compared to the control population. gut guardian can help support histamine intolerance and allergies. Findings Here Gut Guardian Prevalence of DAO deficiency in HIT In human studies, 80% of patients showing symptoms of HIT also demonstrated DAO deficiency. Symptoms of HIT include: urticaria pruritus diarrhoea abdominal pain vomiting constipation cough rhinitis If DAO production is low, histamine blood serum will inevitably be high. This is where the liver needs to be functioning effeciently, to assist with excess histamine metabolism. Liver Guard Diagnosing HIT Currently the general rule of thumb is that two or more symptoms of HIT are being presented. Other gastrointestinal pathologies should also be dismissed. Low histamine diets are recommended in the short term, to establish remission or improvement in symptoms. Low Histamine Diets Foods that potentially contain high levels of histamine are: a) those microbiologically altered, such as fish and meat, or derived products that may have been preserved or processed in unsuitably hygienic conditions. b) fermented products, in which the bacteria responsible for the fermentation process may also have aminogenic capacity. If you would like more information on low histamine diets check out our blog here. Low Histamine Diets for Dogs More are now acknowledging the role of DAO inhibitor medications and the result on histamine load. In addition, we must consider how the health of the gut may be influencing enzyme capacity and so we really need to take a look at the bigger picture. Does My Pet Need to Detox 7 Steps to Optimal Gut Health for Pets If any of this is ringing a little true for your dog, then please check out our services to see if we may be able to help. Thanks for reading, Team MPN x
In our last My Pet Nutritionist article we explored the range of factors that can contribute to a less than happy gut including: Antibiotics, Overuse of certain medications like proton pump inhibitors and antihistamines, Poor liver function, Poor motility, Digestive disorders, Poor pancreatic function, Inflammation in the gut, Stress Environmental toxins, Dietary choices. And more! Why is this important? The microbiome plays an immense role in both health and disease. It has been seen to affect how food it utilised and absorbed – and in actual fact, you aren’t what you eat, you are what you absorb and utilise! This goes for pets too. The microbiome has also been implicated in obesity. Findings Here The microbiome can produce metabolites which can support immune function, modulate inflammation, and influence behaviour. A happy microbiome also forms a defence barrier so is an important part of gut healing if dealing with pets who suffer with sensitivities. So, if we know what can result in gut dysbiosis, is it something we can prevent? And is it something we can reverse? Let’s take a look. First of all, we are looking at puppyhood to prevent dysbiosis. Until recently, it was believed that foetus development occurred within a sterile uterus, however increasing evidence indicates that the foetus develops in an environment that is not entirely germ-free. Many microbial species have been detected in the umbilical cord, the amniotic fluid and the foetal membranes in apparently normal pregnancies without any indication of inflammation or disease. After birth, the new-born acquires microbes from the environment, food, and nearby animals and humans. In the first month of life, gut microbiota is less stable, and its biodiversity will increase over time. Gut Guardian Alongside this microbial colonisation, the immune system must learn to tolerate antigens present in the environment. Colonisation in the early life stages occurs in conjunction with the development, expansion, and education of the immune system. This suggests that during the first colonisation steps, factors with a negative impact on microbiota composition could pave the way for disease in subsequent years. At this point, delivery mode, along with maternal nutrition and environmental exposure are key factors to consider in promoting a healthy gut in your puppy. As your puppy is growing it is essential to: Avoid the overuse of antibiotics – we are not denying that antibiotics are lifesavers, but they can often be prescribed inappropriately. Avoid the overuse of medications – again, some medications are beneficial in acute disease episodes, but the long-term use of many medications often serves as a band-aid – if you are using chronic proton pump inhibitors or antihistamines for your pet, please check out our services to see if we can help. Support normal motility – avoid stressful triggers and work in conjunction with a behaviourist if your dog struggles with stress resilience. Limit exposure to environmental toxins – cleaning and grooming products, pesticides, plastics, contaminated water etc. Is Your Toxic Home Affecting Your Pet The Importance of (Clean) Water Does My Pet Need to Detox The other factors on our list need a little further discussion. Poor Liver Function The liver is an essential organ of the body that performs hundreds of vital functions. We often call it the powerhouse of the body here at My Pet Nutritionist. Some of its main roles include removing waste products and foreign substances from the bloodstream, regulating blood sugar levels, and creating essential nutrients. In addition, it is involved in: Albumin Production: Albumin is a protein that keeps fluids in the bloodstream from leaking into surrounding tissue. It also carries hormones, vitamins, and enzymes through the body. Filters Blood: All the blood leaving the stomach and intestines passes through the liver, which removes toxins, by-products, and other harmful substances. Regulates Amino Acids: The production of proteins depends on amino acids. The liver makes sure amino acid levels in the bloodstream remain healthy and it also plays a role in rearranging amino acids into new proteins. Regulates Blood Clotting: Blood clotting coagulants are created using vitamin K, which can only be absorbed with the help of bile, a fluid the liver produces. Resists Infections: As part of the filtering process, the liver also removes bacteria from the bloodstream. Stores Vitamins and Minerals: The liver stores significant amounts of vitamins A, D, E, K, and B12, as well as iron and copper. Processes Glucose: The liver removes excess glucose (sugar) from the bloodstream and stores it as glycogen. As needed, it can convert glycogen back into glucose. Bile Production: Bile is a fluid that is critical to the digestion and absorption of fats in the small intestine. Bile acids also affect the balance of flora and gut motility, which ultimately affects microbiota composition. But of further interest, there seems to be a bi-directional relationship here as gut dysbiosis is also then implicated in poor liver function and subsequent liver disease. We’re not kidding when we say we need to consider a whole-body approach to health (and disease). And so, if you are looking to support the microbiome, we also need to be supporting the liver (and more – but one step at a time!). Liver Guard Poor Diet – as the liver plays a role in metabolism and detoxification, the less burden we place on it, the better. Bioavailable, nutrient dense foods are best – which is why we advocate a whole-food, fresh diet. Stress – again, the liver plays a role in detoxification, so if the body has plenty of stress hormones to break-down and excrete, the burden on the liver will be increased. Avoid stressful triggers as much as possible. Endocrine disease/disorder – vet checks can establish if this is a consideration that needs to be made but underlying endocrine issues can contribute to impaired liver function. Infectious agents – many infections may affect the liver, and so testing for this is beneficial. Immune support can then be useful in a liver healing plan. Vaccinosis – here we are looking at the burden
Here at My Pet Nutritionist, we often track many health concerns back to the administration of flea and tick treatments. Whilst correlation is not causation, there is still a correlation. So let’s take a look at how they work and see if we can understand why we don’t recommend them. Grab a cuppa, and sit tight! Permethrin, discovered in 1973, is predominantly administered as a spot-on formulation but has also been formulated in collars. A bit wordy but, permethrin works after contact with the arthropod and absorption into the arthropod either directly through the outer cuticle or through ingestion during feeding on the host. Permethrin is distributed throughout the arthropod nervous system. As this occurs, it interferes with the voltage-gated sodium channels of neurons by slowing down the activation and inactivation process of the sodium channel gates and significantly prolonging sodium ion influx. What this means is that it causes continuous nerve charges, resulting in restlessness, incoordination, tremor, paralysis, respiratory failure, and eventually arthropod death. It acts on the nervous system of the flea to kill it. Permethrin is touted for its fast metabolism in dogs – but cats lack the same enzyme necessary for this process, so any cats that are in contact with dogs who have been treated often show signs of toxicity – hypersalivation, motility disorders, lameness and in some cases death. Check out our article on cat detoxification here. Flea repellence is difficult to appropriately define and measure because fleas attack and bite so rapidly after arriving on the host – for this reason, it is claimed that products like this are designed to reduce flea numbers in the household, rather than to prevent new fleas from taking a bite. Fluralaner is a novel, recently developed chewable tablet, and a molecule of the isoxazoline class. Isoxazolines block the ligand-gated chloride channels of both GABA and glutamate receptors (and as we know these are chemical messengers in the nervous system). After oral administration and absorption int he digestive tract or topical administration and transdermal absorption, fluralaner is rapidly distributed by the circulatory system and maximum plasma levels are on average reached within 24 h after oral or approximately 7 days after topical administration in dogs. This compound has a slow-clearance rate in the body. Fluralaner is a systemically distributed anti-parasitic agent and, by definition, is not a repellent. The reason these products are used is to mitigate the risk of tick-borne disease is to disable the critter when they have latched on to your dog but a review carried out on the efficacy of flea and tick products concluded that there are no currently available acaricidal treatment that can completely prevent transmission of tick-borne diseases. Findings here The other reason these products are used is often if there are known allergies to fleas. But as these products don’t repel, you still run the risk of contact whilst the flea is being killed from ingesting the toxic compound. So, if these products don’t repel, is there anything we can do that can? 1) Start in the Garden! Plant pots of lemon balm, sage, rosemary, lemongrass, basil, and mint! These aromas are great for repelling those pesky fleas! Lemon balm, or Melissa officinalis L., grows natively in West Asia,North Africa, and parts of Europe. As the name suggests, lemon balm has a lemony scent and flavour. And whilst you’re growing some, you may as well note the additional benefits: Antiviral Antispasmodic Improve cognitive function Promote digestion and mitigate griping pains Antioxidant Hepatoprotective Immunomodulatory Findings here 2) Apple Cider Vinegar! ACV can be added to water to support gut health in the dog, but it can also be used as a coat rinse – the smell is particularly repellent, to most! Never use neat, always dilute with filtered water. 3) Neem! Neem has a range of functions including: Fungicide – effective in cases of ringworm, yeast overgrowth and many more fungi species Antibacterial – neem has effectively suppressed several species of pathogenic bacteria Antiviral Insecticidal Controlling intestinal worms Findings here 4) Mint! Not just a breath freshener, it also repels pesky visitors. However, peppermint has been seen to possess the following benefits too: Antibacterial: Peppermint has demonstrated antimicrobial effects against a range of nasties, including:e.coli, salmonella, streptococcus, staphylococcus, Enterobacter and more! Attention is being paid to its role against multi drug resistance bacteria. Antifungal: Peppermint ha sbeen seen to have good fungicidal action against candida, and dermatophytic fungi. Findings here The reason we have considered additional benefits of these herbs is because worse outcomes are usually associated with a poorly functioning system – and so, in repelling nasties, and mitigating the risk of a burden, it is essential to take a whole health approach to parasite control. Ironically, the very administration of some of these treatments is often associated with a subsequently poorly functioning system. Reviews have even concluded that there is strong evidence that products not only target fleas and ticks but they compromise the health of the non-target species, in this case, the dog. Findings here And so, the single best thing we can do to support the overall health of our pets is provide a fresh, whole-food diet, use natural repellants, to find out more, click here. The body has cells, which have jobs to do. To do those jobs, they need nutrients, and whilst some nutrients can be synthesised in the body, many are ingested through the diet. Ensure the diet is full of bioavailable protein, fat, and a range of micronutrients. In order to fight any nasties that appear, a strong immune system is key, check out our article here to learn more about the function of the immune system here and for some top foods to help support it here. If you are concerned that any treatment you have administered has compromised your dog’s system, as the above review highlights, then check out our article on detoxification here and also ensure you are supporting their gut health here. If you would like any support with your dog’s health,
Well, the sun is shining, and the buds are on some of the trees. Whilst it is a great time of year and you feel like anything is possible, it is also the time that seasonal allergies start to rear their ugly head! Whilst many dogs simply have a sensitivity to grass sap and keeping them off the freshly mown lawn for a couple of days can help keep pesky irritation at bay, some allergies are a little more complicated. As always, we are available to help you manage any chronic irritation suffered by your dog, but we thought we would give you some of our top tips that can come in handy when managing seasonal allergies. We love Spring here at My Pet Nutritionist, however we don’t love all of the poor itchy dogs we see due to seasonal allergies. What is an allergy? An allergy is a hypersensitivity with a basis in immune mechanisms. Seasonal allergies tend to manifest as dermatological and respiratory symptoms. Sadly, secondary to dermatological symptoms, dogs can often develop chronic infection from repeated trauma in the form of licking, scratching, or rubbing. Flea allergies are also often deemed as seasonal allergies, and it is the saliva from the flea that causes the irritation. Flea allergies affects animals of all ages, irrespective of sex or breed and there is new data to suggest that puppies given flea protection treatments too early are more susceptible to this disease. It is argued that this is because the young puppy will not be able to acquire immunity to the antigens contained in flea saliva. Findings here For this reason, our first tip is: 1) Avoid the overuse of pharmaceutical flea and worm treatments Whilst there is sometimes a place for the use of pharmaceutical products in high burdens of parasites, we would always advocate the use of worm count kits to establish any burden of worms before treatment and also the use of natural flea repellent products over any spot-on or tablet flea treatment. The overuse of certain pharmaceutical products can place an unusual burden on many pathways in the dog’s body. 2) Support the Gut! As you will know if you read our articles on the immune system and the lymphatic system, in the gut you will find GALT, or gut-associated lymphoid tissue. The digestive tract is heavily laden with lymphocytes, macrophages and other cells that participate in immune responses. As we mentioned, an allergy is an immune response gone bad, so we need to support immune function. In a poor functioning digestive system, rogue particles can end up leaking through the barriers; this can be in cases of periodontal disease (bacteria getting into the blood stream from plaque formation), to damage in the tight junctions in the intestinal tract. But when this happens, the immune response is called to the area of the rogue particle to get rid of it. These systemic responses can lead to hypersensitivity, leaving the immune system a little too eager to do its job on a body wide level. It is essential to support the barriers in the mouth; ensuring good dental hygiene but also to support the barrier of the gut. Bone broth can be a great addition to support gut health. Glutamine is an amino acid that maintains gut barrier integrity and it can be found in bone broth. Read more about gut health here. 3) Limit Stress Mast cells have a key role in allergic response; when they detect a substance that triggers an allergic reaction, they release histamine and other chemicals into the bloodstream. Histamine makes the blood vessels expand and the surrounding skin itchy and swollen. This is known as degranulation and we know that stress can induce mast cell degranulation. Findings here If you are working to tackle allergies in your dog, then it is important to remove as many stress triggers as possible. There is also this idea of co-regulation of species, that dogs can pick up when we are stressed too. We know that seeing our canine companions suffer is worrying, so this is where it can be particularly useful to get a qualified professional on board to help develop a plan of action to move forward. Learn more about how to possibly support stress here. 4) Rinse your dog, but not wash! If you suspect your dog may have sensitivities to certain grasses or pollen, rinse their paws, undercarriage,and chest after walks. You can also wipe their muzzle, ears, and face with a damp microfibre cloth when you get home too. But avoid over-shampooing your dog. Whilst you may opt for non-toxic products, washing can skew the microbiome found on the skin of your dog and this provides a first line of defence for the immune response. The skin has its own community of microbes that can engulf and destroy pesky ones before they have chance to cause problems; frequent bathing can alter this community. 5) Fill up on Fat! As we know, allergies are an immune response and inflammation is the hallmark of an immune response. Therefore, it can help to fill up on foods to down-regulate inflammation. Omega-3 is a fatty acid that has regularly been linked to reduced levels of inflammation. In turn it is often associated with reduced perception of pain (win win!). Omega-3 is found in fatty fish like salmon, mackerel, sprats, and sardines. Fresh or tinned are a great addition to the diet (although be mindful of how much tinned due to mercury content). You will find some content in beef and lamb– just opt for grass fed. There are many fish oil supplements available, just be mindful that as the level of polyunsaturated fatty acids are increased in the diet, the need for Vitamin E also increases. To learn more about your fatty acid options, read here. For some dogs, they can manage seasonal allergies well, with some simple lifestyle changes like: Ensure a fresh diet to give optimal support to your dog’s immunity
If you spotted our My Pet Nutritionist blog last week, then you’ll notice that we didn’t really discuss the lymphatic system with the immune system, despite them being intricately linked. It’s because this system deserves a blog all of its own. So, let’s take a look at what it is and what it does! The lymphatic system is a network of tissues and organs which help the body eliminate toxins, waste, and other unwanted compounds. It is like the sewer system for the body. But it also plays a role in immune function. Like the blood system, the lymphatic system is made up of many vessels that branch all around the body. It is a subset of both the circulatory and immune system. Without it, neither of them would function. The lymphatic system includes: Lymph – a fluid that moves all around the lymph system. It contains a type of white blood cell known as lymphocytes. Lymphocytes – these are white blood cells that fight infection and disease. Lymph vessels – these are tiny tubes that carry lymph fluid around the body. Lymph nodes – these are small, bean-shaped organs. They act as filters for the lymph fluid as it travels all over the body. Lymph nodes are found in the underarms, groin, neck, chest, and belly (abdomen). During infection, lymph nodes swell because of the multiplication of lymphocytes multiplying inside. Function of the Lymphatic System A major function of the lymphatic system is to drain body fluids and return them to the bloodstream. Blood pressure causes leakage of fluid from the capillaries, resulting in the accumulation of fluid in the interstitial space—that is, spaces between individual cells in the tissues. This is where the lymphatic system comes into play. It drains the excess fluid and empties it back into the bloodstream via a series of vessels, trunks, and ducts. But as we mentioned, it also plays a role in the immune function of the host. The lymphatic system is a sort of immune surveillance system. It protects us against pathogens. Our dogs are constantly being invaded by bacteria and viruses; they take them up through food, they breathe them in, and they get in through wounds in our skin.These pathogens must be removed by the immune system. Because the lymphatic system is constantly filtering the contents of the body it collects these micro-organisms which have been engulfed by immune cells and carries them to the lymph nodes. Within the lymph nodes there are T cells and B cells which recognise these pathogens and which multiple in response. So, the lymphatic system acts as a collecting system and therefore an integral part of the immune system. Another role of the lymphatic system is the absorption of fats and fat-soluble vitamins from the digestive system and the subsequent transport of these substances into circulation. The mucosa that lines the small intestine is covered with finger like projections called villi. There are blood capillaries and special lymph capillaries, called lacteals, in the centre of each villus. The blood capillaries absorb most nutrients, but the fats and fat-soluble vitamins are absorbed by the lacteals. The lymph in the lacteals has a milky appearance due to its high fat content and is called chyle. Organs and Tissues of Interest The primary lymphoid organs are the bone marrow, spleen, and thymus gland. Tonsils are known as lymphoid nodules. The lymphoid organs are where lymphocytes mature, proliferate, and are selected, which enables them to attack pathogens without harming the cells of the body. As we explored in the guide to the immune system, lymphocytes are the primary cells of adaptive immune responses. The two basic types are B and T cells – B cells maturing in the bone marrow, and T cells maturing in the thymus. Bone marrow is the spongy tissue in the middle of the bigger bones in the body. The bone marrow makes blood cells from stem cells. These are undeveloped cells that can divide and grow into different types of blood cells needed by the body including red blood cells, platelets, and white blood cells. This is where lymphocytes are made. The thymus is in the thoracic cavity, just under the neck. It’s made up of two lobes of lymphoid tissue. Each lobe has a medulla surrounded by a cortex. The cortex is where immature lymphocytes first go to become T cells, but their maturation finishes in the medulla. The spleen is in the upper-left part of the abdomen. It is tucked up under the ribs. The spleen’s main function is to filter the blood. It removes old or damaged red blood cells, which are phagocytised by macrophages. The spleen also detects viruses and bacteria and triggers the release of lymphocytes. But as the main entry for microbes into the body is through mucosal surfaces, most of the lymphoid tissue is located within the lining of the respiratory, digestive, and genitourinary tracts. These are known as MALT and GALT. MALT is mucosa associated lymphoid tissues, and GALT is gut-associated lymphoid tissue. Tonsils are an example of MALT. The tonsils are masses of lymphoid tissue found in the back of the throat and nasal cavity. Tonsillitis is when they become swollen and typically a sign of infection. Peyer Patches within the small intestine are also MALT. They are like the tonsils for the digestive system. The function of Peyer’s Patches is to analyse and respond to pathogenic microbes in the ileum. They trap foreign particles survey them and then destroy. What can go wrong with the lymphatic system? Enlarged (swollen) lymph nodes (lymphadenopathy): Enlarged lymph nodes are caused by infection, inflammation, or cancer. Swelling or accumulation of fluid (lymphedema): Lymphedema can result from a blockage in the lymphatic system caused by scar tissue from damaged lymph vessels or nodes. Cancers of the lymphatic system: Lymphoma is cancer of the lymph nodes and occurs when lymphocytes grow and multiply uncontrollably. For dogs, lymphoma can arise in the skin. Summary The lymphatic system is an extensive drainage network that helps keep bodily fluid levels in balance and defends the body against infections. It is made up
Here at My Pet Nutritionist, we often find that in many cases, immune function in some pets has gone a little awry. Being the thing that quite literally keeps us alive, you can see, how optimal immune function is kind of important. So, we thought we’d give you a run through on its function. What is the Immune System? When the body is invaded by bacteria, a virus or parasites, an immune alarm goes off, setting off a chain reaction of cellular activity in the immune system. Specific cells are deployed to help attack the invading pathogen. Those cells often do the job, and the invader is destroyed. But sometimes, when the body needs a more sophisticated attack, it turns to a more specialised set of cells. These cells are like the special ops of the immune system—a line of defence that uses past behaviours and interactions to tell it exactly how to deal with the threat. The immune system is responsible for all of this, and not surprisingly is has many systems to mobilise action. We tend to explore the immune system in terms of innate immunity and adaptive or acquired immunity. Innate immunity is what everyone is born with – it’s a type of general protection. The innate immune system provides the first line of defence; broadly divided into physical and chemical barriers and nonspecific responses. The physical barriers include the skin and mucosa (a membrane that lines cavities in the body) of the digestive and respiratory tracts. Saliva, tears, and mucous (that sticky material) all help to provide a barrier, as does the microbiome of the skin and gut. In the gut, stomach acid also provides a first line of defence as its acidity level can kill off potentially harmful pathogens. Hair inside the nose also traps pathogens and environmental pollutants. This is where you’ll recognise the age old having something stuck up your nose when you are viciously sneezing! Pathogens that sneakily get past these first defences are then tackled by the next row of soldiers in the innate immune system. There area number of white blood cells involved in innate immunity: Monocytes which develop into macrophages Neutrophils Eosinophils Basophils Natural Killer Cells But there are also other participants: Mast Cells The Complement System Cytokines Macrophages develop from a type of white blood cell called monocytes. Monocytes become macrophages when they move from the bloodstream to the tissues. They ingest bacteria, foreign cells, damaged and dead cells. This process is called phagocytosis, and cells that do the ingesting are called phagocytes. Macrophages secrete substances that attract other white blood cells to the site of the infection. They also help T cells recognise invaders and therefore also participate in acquired immunity (which we’ll come to later). Neutrophils are among the first immune cells to defend against infection. They are phagocytes, which ingest bacteria and other foreign cells. Neutrophils contain granules that release enzymes to help kill and digest. Neutrophils also release substances that may trap bacteria, preventing them from spreading and making them easier to destroy. Eosinophils can ingest bacteria, but they also target foreign cells that are too big to ingest. Eosinophils contain granules that release enzymes and other toxic substances when non-self-cells are encountered which make holes in the target cell’s membranes. They also produce substances involved in inflammation and allergic reactions. We know this because those suffering with allergies, parasitic infections, or asthma tend to have more eosinophils in the bloodstream than those not suffering with the conditions. Natural killer cells are ready to kill as soon as they are formed. They attach to infected cells or cancer cells, they then release enzymes and other substances that damage the outer membranes of these cells. NK cells play a role in the initial defence against viral infections, and they produce cytokines that regulate some of the functions of T cells, B cells, and macrophages too! We’ll look at T and B cells later. Also involved in the inflammatory response, mast cell function resembles that of basophils in the blood. When they encounter an allergen, they release histamine. Histamine causes blood vessels to widen, thereby increasing blood flow to the area and so, we have the usual signs like redness, heat, swelling and pain associated with inflammation. The complement system consists several proteins that function in a sequence. One protein activates another,which activates another, and so on to defend against infection. This is known as the complement cascade. Complement proteins play a role in both innate and acquired immunity. They kill bacteria directly,help destroy bacteria by attaching to them, they attract macrophages and neutrophils, neutralise viruses, help immune cells remember invaders, promote antibody formation, and help the body eliminate dead cells and immune complexes. Cytokines are the messengers of the immune system. White blood cells and other cells of the immune system produce cytokines when an antigen is detected. There are many different cytokines, which affect different parts of the immune system. Some cytokines stimulate activity – asking the white blood cells to become more efficient killers, some cytokines inhibit activity, signalling an end to an immune response and some are known as interferons, which interfere with the reproduction of viruses. Cytokines also participate in acquired immunity. Acquired (adaptive or specific) immunity is not present at birth. It is learned. Its job is to learn, adapt and remember. It’s almost like a cheesy advert for a local school! Acquired immunity does take time to develop after exposure to a new antigen, but afterwards, the response is quicker and more effective! Key Definitions Antibody – Antibodies are specialised, Y-shaped proteins that bind like a lock-and-key to the body’s foreign invaders — whether they are viruses, bacteria, fungi, or parasites Antigen – An antigen is any substance that causes the immune system to produce antibodies against it. The white blood cells responsible for acquired immunity are Lymphocytes which include T and B cells. There is also a role for others in acquired immunity which include dendritic cells, cytokines, and the complement
Here at My Pet Nutritionist, skin issues are one of the most common complaints from dog owners. Whilst there are a number of factors that can result in not-so-comfortable skin for your companion, there are also some top tips that can start you off the right foot. So, let’s take a look at the skin in a little more detail and what can do to promote its health. The skin is the largest organ of your dog’s body. It consists of three major layers: The Epidermis – (Epi – upon or above) this is the outer layer of skin, the protective layer. The Dermis – the dermis supports and nourishes the outer layer. It provides strength and elasticity. Here you will find collagen fibres, sweat glands, sebaceous glands, and hair follicles. You will also find cells that release histamine and other inflammatory mediators when faced with an allergy or injury. The Subcutis – (sub meaning under or below) this in the innermost layer of the skin, where you will find fat and muscles. Subcutaneous fat provides insulation, padding and storage for reserve energy. Not only does the structure of the skin prevent water and electrolyte loss to help maintain body homeostasis, but it forms a protective barrier which helps protect against infections, parasites, and the elements. This is the often-forgotten role of the skin –that it forms part of the immune system. We have three lines of defence in the immune system: The first line of defence are the physical barriers, the skin and mucous membranes of the gut and respiratory tract. The second line of defence is defined as innate immunity. This system surveys and neutralises pathogens by mounting an inflammatory response. This system communicates with the third line of defence which is adaptive immunity. Adaptive immunity provides a specific and tailored response, deploying T and B cells. Ultimately, for us, or our dogs to survive and thrive, we, and they need robust immune defences, so it makes sense to want to strengthen our first line as much as possible. 1) Sleep! In the dermis of your dog’s skin, you will find connective tissue which contains collagen. Collagen fibres play a vital role in maintaining structural integrity and it is supported by hyaluronic acid (in ageing human, skin hyaluronic acid is often absent leading to the presence of fine lines and wrinkles). Cortisol, however, significantly decreases the synthesis of hyaluronic acid. Findings here As we know, cortisol is one of the main stress hormones, released in times of fight or flight. In short, stress results in lower hyaluronic acid, impacting collagen and therefore skin structure. There are many stress triggers for your canine companion, but lack of sleep is often missed. Not only does low sleep duration influence the perception of stress for days following, but sleep deprivation is in fact a form of neurobiological and physiological stress (or torture, for us at My Pet Nutritionist). In 1894, Marie De Manaceine was fascinated with sleep deprivation. She had established that mental disturbance resulted from partial insomnia, but she wanted to know more. So, in her Lab, she recruited puppies. 10 to be specific; aged 2, 3 or 4 months old. Whilst they continued to be fed by their mother, she kept them in constant activity. In short, she deprived them totally of sleep. After 96-120 hours, the puppies were irreparably lost. We shed a tear when we read this! What is interesting (despite it being macabre), is that when puppies were starved, they could be saved after 20-25days. This wasn’t possible when they were sleep deprived. Marie found that sleep deprivation significantly affected the puppy’s brains. When they were starved, the brain was left almost spared. But, in the absence of sleep; fat degeneration, blood vessel abnormalities and haemorrhaging occurred. Findings here In a world that never sleeps, both us and our dogs really need to. Adult dogs, in a laboratory setting, when left, will sleep on average for around 13 hours per day. Puppies can sleep anywhere between 18-20 hours per day. Dogs are diurnal, meaning they are active during daylight hours. Rest occurs during dark periods with activity increasing the two hours before light. Dogs have a natural rest period around noon and then reduced activity during the afternoon. Findings here Interestingly, the experiences that your dog has, can affect the type and quality of sleep they experience. Studies have found that after a negative experience, dogs will fall asleep more quickly. It is thought that this is a protective sleep, in response to stress. This should be in the forefront of your mind. It is all too easy to attribute an “exhausted” dog to the busyness of the day. Be mindful, their sleeping habits could be more indicative of their experience. Findings here Sleep is vital for your dog’s overall health, but also in helping their body synthesise the compounds it needs to build a robust skin. Build in plenty of rest time for your dog, at the times they would naturally do so. 2) Feed Fresh Food! We probably sound like a stuck record here at My Pet Nutritionist, but fresh really is best! Processed, high glycaemic index foods wreak havoc with skin! There are a few different reasons, but glycation is one of them. Glycation is the modification of proteins or lipids after exposure to sugars. You may notice them referenced as AGEs, advanced glycation end products. Glycation leads to a loss of protein function and impaired elasticity of tissues like blood vessels, tendons and of course skin. AGEs have been associated with many metabolic disorders and are closely related with renal failure and diabetes. They also increase with age. AGEs can be synthesised in the body, but total load also includes dietary exposure. It is clear that foods ranking high on the glycaemic index result in a higher accumulation of AGEs. Not only that, but maillard reactions, those generated in the heat processing of foods, also result in AGEs. Another reason why
Autoimmune disease, irritable bowel disorders, lupus, thyroid issues, eisonophilic skin disorders, chronic skin disease and allergic dermatitis, not a list any owner wants to pair with their pet, but sadly all of these diseases can be vaccine-related conditions. We can identify them as vaccine related conditions because symptoms are concomitant with vaccination date. We deem this reaction as vaccinosis. And sadly, it is far more prevalent than we could even imagine. At MPN, we see the correlation of vaccination and disease in many of our clients. So let’s take a look at where we started, and how we ended up in such dire straights. The smallpox vaccine was introduced in 1796 after Edward Jenner observed that milkmaids who had previously caught cow pox didn’t catch smallpox. The idea was that exposure to killed or weakened virus/bacteria that cause disease can prime the immune response, but it doesn’t actually make the host sick. So, vaccinations allow the host to develop immunity without having to suffer the disease. To this end, smallpox is now declared eradicated. There is no doubt that vaccination has been progressive in public health concerns, for both humans and pets, but they were never meant to make the host sick. For a number of reasons, the current vaccinations schedule for our pets, is. There is increasing evidence that over-vaccination is associated with the development or aggravation of immune-mediated disorders and chronic diseases in individual pets that are genetically predisposed. This raises a particularly interesting element that has perhaps been missed when developing the blanket vaccination schedules for our pets. Twin studies, in humans have demonstrated there is a clear genetic role in vaccine response. A growing list of genes have been associated with immune related functions critical to immunological response and much data is concluding it is the status of these genes that is key to immune response. Human data is highlighting that this is one of the reasons vaccines can either elicit partial, complete or failure to protect individuals treated under the same conditions. This would also suggest that the opposite is therefore true; gene status could elicit partial or complete adverse reaction, or hopefully failure to demonstrate adverse reaction. Genes are a set of instructions and there are a number of factors that can affect how they are expressed. This is likely understood in the canine world to some extent because most vaccines are advised as safe for healthy dogs but not those with a compromised immune system. So, what constitutes a compromised immune system? The primary role of the immune system in dogs is to protect against foreign invaders, or abnormal cells that invade or attack. The immune system must distinguish between self and non-self. Substances that stimulate a response are antigens. These can be contained within bacteria, viruses or microorganisms or cancer cells. They may also exist on their own, like pollen or food particles. There are three lines of defence, physical barriers, non specific immunity and specific immunity. Physical barriers are the first line of defence, they include the skin, the cornea of the eye and the membranes lining the respiratory, digestive, urinary and reproductive tracts. The key is to keep these barriers unbroken. These barriers are also defended by bacteria and secretions that contain enzymes that can destroy harmful bacteria. Examples include eye tears, secretions in the digestive tract and the microbiome in the gut. Nonspecific immunity should be present at birth; it treats all foreign substances in the same way. Inflammation results in white blood cells travelling into tissues to kill invading organisms and remove injured cells. Specific immunity is acquired and developed as the immune system encounters different antigens, it learns the best way to attack and develops a memory for that specific antigen. It takes time to develop a response, but in future encounters, the response is more rapid. Specific immunity involves the action of lymphocytes (B and T cells), antibodies, antigen presenting cells and cytokines. Most vaccines work by stimulating the development of specific immunity. But the immune system does not always function properly, it can be underactive and overactive. An underactive system puts the animal at risk of infection, but an overactive immune system can attack parts of its body that it misidentifies as being foreign. This is what happens in autoimmune conditions. The immune system can also overreact and produce too many antibodies or other chemicals; these are what we see as hypersensitivity or allergic reactions. Not only do we have to ensure the physical barriers remain healthy, but we also must ensure that responses are just right. We know that genes play a role in this, but so does the environment your dog (exposure to toxins, chemicals and pesticides etc) alongside nutrition. Each cell in every body uses chemical reactions to build some of the materials that it needs, converting substances provided by the diet into other chemicals necessary for normal functioning. This is why the immune system has its own micronutrient (vitamin and mineral) requirements. For example, Vitamin A helps to maintain structural and functional integrity of mucosal cells in innate barriers like the skin and respiratory tract, Vitamin D stimulates immune cell proliferation and cytokine production, helping to protect against infection, B12 has roles in natural killer cell functions just as folate maintains natural killer cells. Many micronutrients play a role in protecting against reactive oxygen species and reactive nitrogen species which are produced when pathogens are killed by immune cells. Findings here So, there are many things that can compromise an immune system, which also informs whether the dog is a candidate for vaccination and indeed subsequent and frequent booster vaccinations. Signs your Dog may have a compromised immune system: Tiredness/lethargy Increased stress levels Digestive issues Slow healing wounds Frequent infections (eyes, ears etc) Delayed growth/development Skin sensitivities/allergies Joint stiffness and disease Other diagnosed disease If your dog is suffering with any pre-existing health conditions, it pays to consider titre testing. No animal should be vaccinated with a compromised immune system.
A global infection of both humans and animals, leptospirosis is on the tip of most owners and dog professional’s tongue. Caused by the pathogen icleptospira spp. it is a major zoonosis, with infection acquired from wild and domestic animals. Canine leptospirosis presents very similarly to the syndromes presented in other species with hepatic, renal and pulmonary ramifications. In short, it’s pretty rough, but vaccine induced immunity is restricted to serologically related serovars and is generally very short-lived; therefore, needing annual revaccination. If there are more than 230 serovars belonging to at least ten pathogenic species, does the vaccine even pose benefits? Or do the risks outweigh them? We are going to look at the science and explore both sides to this story. Fancy coming along for the journey? Leptospirosis is characterised by fever, jaundice, vomiting, diarrhoea, renal failure, haemorrhages and ultimately death. However, for those who recover, they may become asymptomatic renal carriers for extended periods and shed infectious leptospires into the environment. This is a large source of infection, as rats can be carriers but do not show signs of infection. Whilst treated dogs can shed leptospires, so can vaccinated dogs. This raises the first red flag; is this potentially increasing exposure? Most signs of leptospirosis become apparent in the first week after infection; younger dogs, less than 1 year of age tend to get the most severe forms of leptospirosis and 87-100% of infected dogs will have some degree of renal implication. There do appear to be different clinical parameters of the infection: Peracute Disease: super-sudden onset which usually affects younger dogs with an overwhelming exposure. The large amount of toxin causes rapid death before the kidney or liver disease even occurs. Acute Disease and Subacute Disease: this is the classic form which manifests as fever with bruising and bleeding, general muscle pain and painful abdomen from kidney and/or liver disease. There may be jaundice and inflammation in the eyes. Chronic Disease: recurring fevers, chronic hepatitis, chronic kidney disease, uveitis, poor appetite and weight loss. However, leptospira interrogans sensu lato is sensitive to doxycycline which is a readily available antibiotic. Leptospires are cleared from the blood within 24 hours of starting antibiotics. But it does take around 7 days to clear from the urine. Prognosis, depending on organ damage is 80-90% with appropriate treatment. There are, however, other serovars, like the pomona which is associated with more severe disease and in severe kidney cases, dialysis can be required which is often limited. So, whilst treatment is largely effective, if started soon enough, there was clearly enough concern to develop a vaccine. Vaccination against leptospira interrogans sensu lato is available for the seravars canicola, grippotyphosa, pomona and icterohaemorragiae. Some vaccines coverall four serovars, whereas some cover two of the four. This is where you will recognise the common lepto two or four vaccine. Vaccination against canicola and icterohaemorragiae has been traditional for dogs and vaccination overall, has been seen to reduce the severity of the disease, but will not prevent infected dogs from being carriers. Note, it supposedly reduces severity, it doesn’t necessarily prevent occurrence. The leptospirosis vaccine was soon associated with a higher chance of vaccine reactions. This is a result of human research into leptospirosis. In the U.K. in 2014 , over 2000 reports of Novibac L4 adverse reactions have been reported to the VMD (Veterinary Medicine Directive) and around 120 suspected deaths related to vaccinosis. In addition to this, data suggested that the severity of the disease was associated with the intensity of the immune response. In short, the more intense and early the response, the more severe the disease. Findings here If our immune system, and our dog’s, is primed to take out antigens and protect, why does a more intense response seem to make things worse? An intense immune response induces a high level of inflammatory cytokines which can result in severe tissue lesions. Immunity is like the porridge in Goldilocks. It can sometimes be too cold (lacking) and sometimes too hot (overzealous). Ideally, we want it, just right. There are many things that affect immune responses, in the case of lepto, a more intense response was associated with previous infection. Fever was induced by virulent injection in previously immunised rabbits whereas non-immunised rabbits exhibited no fever after injection. So, in this case, the immunised rabbits fared poorer than non-immunised rabbits. See where we might be going with this? So we are vaccinating to potentially reduce, not prevent the severity of infection but here it appears those rabbits immunised, had a more severe reaction to exposure. But, stress, nutrition and the environment can all affect immune responses too. So too, can genes. This can help explain why some animals are more, or less susceptible to pathogens (or vaccines) than others. And explain the age-old statement, but my dog was fine! It therefore raises no eyebrows when reports appear of clinical leptospirosis in numerous dogs when they had previously been vaccinated. You’ll remember this from earlier, when it was deemed to reduce severity, not necessary prevent occurrence. This was however, associated with vaccine type. In short, the dogs were vaccinated against only two of the many pathogenic serovars. So, in walked Lepto 4. But these new vaccines were associated with further increases in vaccine reactions, not limited to local swelling or hypersensitivity, but including cardiac abnormalities. Specifically, heart murmurs appearing between first and second vaccination. Findings here What is particularly interesting in studies exploring the use of lepto 4 vaccines, is that dogs demonstrated antibodies to serovars not vaccinated against. Researchers have therefore concluded that natural exposure (not vaccine exposure) to serovars provide positive titre results. Not only that, but in cases of vaccinations up to 1745 days previously, some dogs still demonstrated antibodies. This raises a question around the need for such frequent booster vaccinations. The take home from this particular study was “seroconversion following vaccination differed considerably among individual dogs.” Yet they still concluded that, “in the light of the high incidence and
Cats are obligate carnivores. What this essentially means is that cats rely on nutrients in animal tissues to meet their specific requirements. Not plants…. but animal tissues. So, let’s explore the world of the cat in a little more detail and see how we can support their nutritional needs to not only survive, but thrive. Evolutionary events have led to a unique digestive and metabolic peculiarity. Whilst in many other species, we have the three macronutrients, fat, protein and carbohydrates, cats seem to have no physiological requirements for carbohydrates. Now where this becomes interesting is that the brain and red blood cells have an absolute need for glucose, and we know that carbs equal glucose, so where do cats get glucose from? Surely without carbohydrates they would be forever hypoglycaemic? Well, through a process of gluconeogenesis, they produce glucose. Us humans, and dogs too can perform this process, but cats have it down to a fine art. Gluconeogenesis is the metabolic process by which glucose is produced from non-carbohydrate precursors, like lactate and amino acids (and we know that amino acids are the building blocks of protein). All amino acids, except leucine and lysine are gluconeogenic and alanine is the major gluconeogenic amino acid. The process mainly occurs in the liver, but some processes are carried out in the kidneys and a small portion is carried out in the intestines. It is thought that cats evolved with the process because of their proportionally large brain. As we have mentioned, the brain has an absolute need for glucose, and it is thought that the brain demand for glucose in cats is around 30% whereas for us humans who have a much larger brain is 44%. Cats wouldn’t have been able to consume high enough levels of carbohydrates from their natural prey diet, so their body had to adapt to survive. This evolution has resulted in a small capacity for starch digestion, having limited salivary amylase which is similar to dogs. Amylase is found in the feline pancreas and chyme, but the activity is incredibly low compared to other animals. Their pancreatic maltase activity is also extremely low. Cats seem to know this and when given the opportunity will choose low carbohydrate but high protein diets in order to balance their own macronutrients. They also don’t appear to have developed a sweet tooth. In evolutionary terms, us humans would have stocked up on sweet-tasting foods, but cats didn’t need to. To that end, they don’t show any preference for natural sugars or artificial sweeteners. In the absence of protein, cats will opt for fat. When fat and protein is limited, but carbohydrate is unlimited, cats appear to experience nutritional deficits. This is largely due to their requirement for taurine. Taurine is present in a range of meats and seafoods but is essentially absent from plant material. This is another reason why cats are deemed obligate carnivores. Dietary deficiency of taurine is linked with a range of important conditions. Retinal Degeneration More commonly known as retinal atrophy, it is the complete or partial wasting of the retina. The cells degenerate over time, eventually leading to blindness in the cat. First signs include the eye being more reflective and the pupils are more dilated than normal. Lesions are usually bilaterally symmetrical. A dietary deficiency must be present for several months before changes appear but lesions are progressive whilst the cat is on a deficient diet, although visual defects don’t tend to appear until the late stages of degeneration. Reproduction Taurine deficiency is well known for having marked effects on reproductive performance and on the growth and survival of the young. Cerebellar dysfunction often occurs in kittens of taurine deficient mothers. Dilated Cardiomyopathy Taurine deficiency can lead to weakening of the muscle cells in the heart, causing a condition called dilated cardiomyopathy (DCM). Taurine is essential in membrane stabilisation. Many cases of feline dilated cardiomyopathy are associated with low plasma taurine levels and when administered with taurine, they show an improvement. Sadly, when left untreated for too long, dilated cardiomyopathy will progress to heart failure and death. The importance of taurine in commercial cat food was noted in the late 1980’s; following reformulation of cat foods, cases of taurine related dilated cardiomyopathy decreased from 28% to just 6%. Findings here Including taurine, eleven amino acids are recognised as essential for the cat, but some have a higher utilisation than others. Taurine is necessary for vision and the function of the cardiac muscle, nervous system, immune system, and reproductive systems. Arginine is used in the urea cycle and methionine and cysteine are incorporated into antioxidants, hair and urinary outputs but are primarily gluconeogenic amino acids, catabolised to provide energy. With their incredible utilisation of amino acids, cats present what is known as a carnivore connection. This is a bundle of carbohydrate-sensitive conditions, first noted in humans who were late to join the carbohydrate-eating party (Paleo-Indians, Australian Aborigines for example). In short, there is a higher incidence of conditions like glucose intolerance, insulin resistance and diabetes. However, other data has suggested that carbohydrate content is of little effect, and these conditions are instead associated with overweight or obese cats. 44% of cats in the UK are deemed as overweight or obese by veterinary professionals. Whereas when surveyed, only 8% of owners think their cat needs to lose any weight. Obesity is defined as abnormal or excessive fat accumulation that presents a risk to health. This is a result of excess calories that the body cannot use; these calories can be from any of the macronutrients. It is often considered that a major factor driving obesity is the practice of free-feeding, in which a bowl of dry food is available for consumption by a cat throughout the day, and simply topped up as it runs out. There is also recent research that suggests feeding cats just once a day may control hunger better than several feeds a day. Findings here This study demonstrated that the cats showed a faster
