{"id":45749,"date":"2026-02-10T12:53:10","date_gmt":"2026-02-10T05:53:10","guid":{"rendered":"https:\/\/first-reach.org\/en\/?p=45749"},"modified":"2026-03-26T08:05:28","modified_gmt":"2026-03-26T01:05:28","slug":"pet-food-gut-health-guide","status":"publish","type":"post","link":"https:\/\/first-reach.org\/en\/contents\/pet-food-gut-health-guide\/","title":{"rendered":"Gut health in dogs and cats: physiological functions and evolving market trends"},"content":{"rendered":"\n<p>In pet food development, <strong>\u201cgut health\u201d<\/strong> is no longer a simple matter of \u201cadding oligosaccharides or lactic acid bacteria.\u201d<\/p>\n\n\n\n<p>The gut is not only the site of nutrient digestion and absorption\u2014it is increasingly viewed as a <strong>functional organ<\/strong> that can influence the whole body through <strong>fermentation (microbial metabolism), the mucosal barrier, and gut-associated immunity<\/strong>, potentially affecting systemic inflammatory tone, metabolism, and even behavior.<\/p>\n\n\n\n<p>In addition, because <strong>dogs and cats differ in digestive physiology and nutrient utilization<\/strong>, the optimal approach to \u201cgut health support\u201d is not the same for both species. In this article, aimed at <strong>R&amp;D leaders at pet food companies<\/strong>, we organize the following points with clear rationale and supporting evidence.<\/p>\n\n\n\n<ul class=\"wp-block-list is-style-list__border-bottom is-style-item__alert has-dark-white-background-color has-background\">\n<li>What happens in the small intestine vs. the large intestine (division of roles)<\/li>\n\n\n\n<li>Practical design targets for defining a \u201chealthy gut state\u201d<\/li>\n\n\n\n<li>Mechanisms by which gut health can influence the whole body<\/li>\n\n\n\n<li>Evidence-based effects shown in studies (dogs and cats)<\/li>\n\n\n\n<li>Practical formulation and process considerations for product design<\/li>\n\n\n\n<li>Validation design: what to measure to say \u201cit worked\u201d<\/li>\n\n\n\n<li>Current demand trends in Western markets and what\u2019s next (research \u00d7 market)<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Digestive tract basics in dogs and cats: roles of the small and large intestine<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Small intestine: the main battlefield for digestion and absorption<\/h3>\n\n\n\n<p>Most digestion and absorption of key nutrients occurs in the small intestine. With pancreatic enzymes, bile acids, and brush-border enzymes, nutrients are broken down into absorbable forms, taken up by intestinal epithelial cells, and delivered to the liver primarily via the portal vein.<\/p>\n\n\n\n<ul class=\"wp-block-list is-style-item__arrow has-dark-white-background-color has-background\">\n<li><strong><span class=\"epb-underline-01\">Protein<\/span>:<\/strong><br>After initial breakdown in the stomach, proteins are further digested in the small intestine by pancreatic proteases into peptides and amino acids. Final absorption occurs mainly through small-intestinal epithelial cells and nutrients move to the liver via the portal circulation.<br>\u3000<\/li>\n\n\n\n<li><strong><span class=\"epb-underline-01\">Fat<\/span>:<\/strong><span class=\"epb-underline-blue\"><br><\/span>Fats are emulsified by bile acids and then hydrolyzed by lipase into fatty acids and monoglycerides. Long-chain fatty acids are absorbed and then transported as chylomicrons, largely via the lymphatic system into the bloodstream.<br>\u3000<\/li>\n\n\n\n<li><strong><span class=\"epb-underline-01\">Carbohydrates (starch, etc.)<\/span>:<\/strong><br>Pancreatic amylase breaks starch into oligosaccharides, which are then converted to monosaccharides by brush-border enzymes and absorbed. Some fractions\u2014such as resistant starch\u2014escape digestion and reach the large intestine.<br>\u3000<\/li>\n\n\n\n<li><strong><span class=\"epb-underline-01\">Vitamins and minerals<\/span>:<\/strong><br>Many are absorbed in the small intestine. When digestion\/absorption is impaired (e.g., mucosal damage or exocrine pancreatic insufficiency), weight loss and chronic diarrhea can result.<\/li>\n<\/ul>\n\n\n\n<div class=\"epb-box epb-has-box-margin-item is-style-epb-border-headline\" style=\"--epb-box-padding-top:16px;--epb-box-padding-right:16px;--epb-box-padding-bottom:16px;--epb-box-padding-left:16px;--epb-box-margin-item:8px;--epb-box-padding-background-color:#ffffff;--epb-box-border-style:solid;--epb-box-border-color:#cf2e2e;--epb-box-border-width-top:2px;--epb-box-border-width-bottom:2px;--epb-box-border-width-left:2px;--epb-box-border-width-right:2px;--epb-box-radius:3px\"><div class=\"epb-box__headline icon-lightbulb \" data-fontweight=\"normal\" style=\"text-align:left;--epb-box-headline-background-color:#cf2e2e;--epb-font-sp:14px;--epb-font-tablet:14px;--epb-font-pc:16px;line-height:1;letter-spacing:0.05em;color:#ffffff\">Key point<\/div><div class=\"epb-box__body\">\n<p>The first priority in \u201cgut health\u201d formulation is ensuring that nutrients that should be digested and absorbed in the small intestine are fully processed there. If this foundation fails, undigested material flows into the colon, driving excessive fermentation and putrefaction\u2014often leading to unstable stool quality.<\/p>\n<\/div><\/div>\n\n\n\n<h3 class=\"wp-block-heading\">Large intestine: water\/electrolyte absorption and fermentation<\/h3>\n\n\n\n<p>The large intestine\u2019s primary roles are maintaining water and electrolyte balance through reabsorption, storing and excreting feces, and providing a \u201cfermentation tank\u201d for intestinal microbes. While it absorbs fewer nutrients than the small intestine, it is often the more important site from a dietary-design perspective.<\/p>\n\n\n\n<p>Fermentation in the colon affects stool consistency, odor, and gas\u2014and can also influence immune responses and systemic inflammatory tone.<\/p>\n\n\n\n<ul class=\"wp-block-list is-style-item__arrow has-dark-white-background-color has-background\">\n<li><strong><span class=\"epb-underline-blue\">Reabsorption of water and electrolytes (e.g., sodium)<\/span>:<\/strong> <br>The colon reabsorbs water and electrolytes, helping stool achieve appropriate firmness. If colonic function is compromised, water is not adequately absorbed and \u201clarge-bowel diarrhea\u201d can occur (often characterized by mucus, straining, and frequent small-volume stools).<br>\u3000<\/li>\n\n\n\n<li><strong><span class=\"epb-underline-blue\">Fermentation<\/span>:<\/strong><br>Dietary fibers, non-digestible oligosaccharides (e.g., FOS), and resistant starch are fermented by microbes to produce short-chain fatty acids (SCFAs: acetate, propionate, butyrate). SCFAs serve as key energy sources for colonic epithelial cells. For example, in dogs, acetate\/propionate\/butyrate are often produced in approximate molar ratios around 60:20:10, and butyrate is particularly important as an energy source for colonocytes.<br>\u3000<\/li>\n\n\n\n<li><strong><span class=\"epb-underline-blue\">Putrefaction (protein fermentation)<\/span>:<\/strong> <br>When large amounts of undigested protein reach the colon, microbial protein fermentation increases, producing putrefactive metabolites such as ammonia, phenols, and indoles. These contribute to fecal odor and may burden the colonic mucosa and potentially promote inflammation.<\/li>\n<\/ul>\n\n\n\n<div class=\"epb-box epb-has-box-margin-item is-style-epb-border-headline\" style=\"--epb-box-padding-top:16px;--epb-box-padding-right:16px;--epb-box-padding-bottom:16px;--epb-box-padding-left:16px;--epb-box-margin-item:8px;--epb-box-padding-background-color:#ffffff;--epb-box-border-style:solid;--epb-box-border-color:#cf2e2e;--epb-box-border-width-top:2px;--epb-box-border-width-bottom:2px;--epb-box-border-width-left:2px;--epb-box-border-width-right:2px;--epb-box-radius:3px\"><div class=\"epb-box__headline icon-lightbulb \" data-fontweight=\"normal\" style=\"text-align:left;--epb-box-headline-background-color:#cf2e2e;--epb-font-sp:14px;--epb-font-tablet:14px;--epb-font-pc:16px;line-height:1;letter-spacing:0.05em;color:#ffffff\">Key point<\/div><div class=\"epb-box__body\">\n<p>The large intestine easily becomes the \u201cmain stage\u201d of gut-health effects, but it is also where over-fermentation (gas, soft stool) and putrefaction (odor, inflammatory burden) occur. The colon is a place that must be \u201ctuned\u201d\u2014dietary design must balance \u201cgood fermentation\u201d and \u201cbad fermentation.\u201d<\/p>\n<\/div><\/div>\n\n\n\n<h3 class=\"wp-block-heading\">Key differences between dogs and cats<\/h3>\n\n\n\n<p>Dogs and cats are both monogastric, but their nutritional physiology differs significantly.<\/p>\n\n\n\n<ul class=\"wp-block-list is-style-item__arrow has-dark-white-background-color has-background\">\n<li><strong>Cats (Felis catus):<\/strong><br>Cats are obligate carnivores. They rely heavily on protein and fat metabolism for energy. Their ability to utilize carbohydrates is limited, and their physiological adaptation to high-carbohydrate diets is considered lower.<br>\u3000<\/li>\n\n\n\n<li><strong>Dogs (Canis lupus familiaris):<\/strong><br>Dogs are more omnivorous and have greater carbohydrate digestion and absorption capacity than cats. For instance, dogs generally have higher pancreatic amylase activity and can adapt (to some extent) to higher-starch diets.<\/li>\n<\/ul>\n\n\n\n<p>Anatomically, both dogs and cats have a relatively small cecum and a non-sacculated colon, so their hindgut fermentation capacity is limited compared with herbivores. Reports suggest cats have an even smaller\/shorter cecum than dogs (dogs may have a relatively longer, more spiral cecum, while cats often have a short, comma-shaped cecum).<\/p>\n\n\n\n<p>Therefore, they are not suited to designs that \u201cgenerate energy via extensive hindgut fermentation,\u201d like ruminants or horses. For gut-health in dogs and cats, the goal is typically \u201chigh-quality fermentation even at low volumes (SCFA production)\u201d plus stabilization of stool quality, barrier function, and immune balance.<br>\u3000<\/p>\n\n\n\n<div class=\"epb-box epb-has-box-margin-item is-style-epb-border-headline\" style=\"--epb-box-padding-top:16px;--epb-box-padding-right:16px;--epb-box-padding-bottom:16px;--epb-box-padding-left:16px;--epb-box-margin-item:8px;--epb-box-padding-background-color:#ffffff;--epb-box-border-style:solid;--epb-box-border-color:#cf2e2e;--epb-box-border-width-top:2px;--epb-box-border-width-bottom:2px;--epb-box-border-width-left:2px;--epb-box-border-width-right:2px;--epb-box-radius:3px\"><div class=\"epb-box__headline icon-lightbulb \" data-fontweight=\"normal\" style=\"text-align:left;--epb-box-headline-background-color:#cf2e2e;--epb-font-sp:14px;--epb-font-tablet:14px;--epb-font-pc:16px;line-height:1;letter-spacing:0.05em;color:#ffffff\">Key point<\/div><div class=\"epb-box__body\">\n<p>In cats, it is especially important to account for carnivore metabolism: maximize protein digestibility and avoid excessive fermentation. In dogs, you can incorporate a certain degree of carbohydrate utilization while balancing fermentation for improved stool and gut environment. Species-specific optimization is essential.<\/p>\n<\/div><\/div>\n\n\n\n<h3 class=\"wp-block-heading\">What happens if undigested substrates reach the colon?<\/h3>\n\n\n\n<p>What occurs depends largely on the type of substrate that flows into the large intestine.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">A) Substrates that tend to promote \u201cbeneficial fermentation\u201d<\/h4>\n\n\n\n<p>Highly fermentable fibers, non-digestible oligosaccharides (e.g., FOS), and resistant starch can increase SCFA production, lower intestinal pH, and potentially support the mucosal barrier and local immunity. However, excessive amounts can also cause soft stool and gas\u2014dosage and speed of fermentation must be managed.<\/p>\n\n\n\n<p>For example, studies in dogs report that adding fructooligosaccharides can lower colonic pH and increase SCFAs and beneficial bacteria such as Bifidobacterium and Lactobacillus.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">B) Substrates that tend to strengthen \u201cputrefaction\u201d<\/h4>\n\n\n\n<p>When large amounts of undigested protein reach the colon, putrefactive metabolites increase (ammonia, phenols, indoles), worsening fecal odor and potentially increasing mucosal burden. Research also indicates that high-protein diets can increase protein fermentation markers and putrefactive metabolites in dogs.<\/p>\n\n\n\n<p>For instance, Xu et al. (2017) reported that in healthy, non-obese dogs, a high-protein diet (HP) significantly increased fecal ammonia, branched-chain fatty acids, phenols, and indoles compared with a low-protein diet (LP). Meanwhile, beneficial SCFAs such as acetate and butyrate did not significantly differ, suggesting that under high-protein conditions, \u201cfermentation quality\u201d can deteriorate more easily.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p>In addition, dogs with chronic enteropathy (e.g., IBD-like conditions) have been reported to show reduced fecal SCFAs and reduced microbial diversity, suggesting that disruption of fermentation quality may be linked to disease. Isaiah et al. (2019) found that dogs with chronic enteropathy had significantly lower key SCFAs (e.g., acetate, propionate) than healthy dogs, along with reduced diversity and evidence of dysbiosis.<br>\u3000<\/p>\n\n\n\n<div class=\"epb-box epb-has-box-margin-item is-style-epb-border-headline\" style=\"--epb-box-padding-top:16px;--epb-box-padding-right:16px;--epb-box-padding-bottom:16px;--epb-box-padding-left:16px;--epb-box-margin-item:8px;--epb-box-padding-background-color:#ffffff;--epb-box-border-style:solid;--epb-box-border-color:#cf2e2e;--epb-box-border-width-top:2px;--epb-box-border-width-bottom:2px;--epb-box-border-width-left:2px;--epb-box-border-width-right:2px;--epb-box-radius:3px\"><div class=\"epb-box__headline icon-lightbulb \" data-fontweight=\"normal\" style=\"text-align:left;--epb-box-headline-background-color:#cf2e2e;--epb-font-sp:14px;--epb-font-tablet:14px;--epb-font-pc:16px;line-height:1;letter-spacing:0.05em;color:#ffffff\">Key point<\/div><div class=\"epb-box__body\">\n<p>In gut-health design, the \u201cclassic\u201d approach is not to simply add \u201cgood ingredients,\u201d but first to reduce undigested flow (ensure small-intestinal digestion\/absorption), and then control the <em>quality and quantity<\/em> of substrates reaching the colon. The foundation is maximizing small-intestinal digestion and absorption. Only then should you deliver targeted fermentable substrates to tune colonic fermentation balance.<\/p>\n<\/div><\/div>\n\n\n\n<h2 class=\"wp-block-heading\">Four practical indicators to define a \u201chealthy gut state\u201d<\/h2>\n\n\n\n<p>In simple terms, good gut health means the intestinal environment and function remain stable across digestion\/absorption, defense, and metabolic roles\u2014supporting whole-body health. From a development standpoint, the following four indicators are a useful framework.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">1) Microbiome (gut microbial community)<\/h3>\n\n\n\n<p>A \u201cgood microbiome\u201d is not only about \u201chigher diversity.\u201d Important properties include:<\/p>\n\n\n\n<ul class=\"wp-block-list is-style-list__border-bottom is-style-item__arrow\">\n<li><strong>Stability (resistance):<\/strong> less likely to be disrupted by diet changes or stress<\/li>\n\n\n\n<li><strong>Recovery (resilience):<\/strong> ability to return after disruption<\/li>\n\n\n\n<li><strong>Functional redundancy:<\/strong> multiple microbes able to perform similar functions<\/li>\n<\/ul>\n\n\n\n<p>In dogs and cats, microbiome composition is strongly influenced by diet (protein\/fiber\/fat levels; raw vs cooked; etc.). Daily formulation choices shape microbial composition and metabolic capacity.<\/p>\n\n\n\n<p>Some reports suggest dogs may have relatively strong resilience (stability and recovery) even under dietary shifts.<br>\u3000<\/p>\n\n\n\n<div class=\"epb-box epb-has-box-margin-item is-style-epb-border-headline\" style=\"--epb-box-padding-top:16px;--epb-box-padding-right:16px;--epb-box-padding-bottom:16px;--epb-box-padding-left:16px;--epb-box-margin-item:8px;--epb-box-padding-background-color:#ffffff;--epb-box-border-style:solid;--epb-box-border-color:#cf2e2e;--epb-box-border-width-top:2px;--epb-box-border-width-bottom:2px;--epb-box-border-width-left:2px;--epb-box-border-width-right:2px;--epb-box-radius:3px\"><div class=\"epb-box__headline icon-lightbulb \" data-fontweight=\"normal\" style=\"text-align:left;--epb-box-headline-background-color:#cf2e2e;--epb-font-sp:14px;--epb-font-tablet:14px;--epb-font-pc:16px;line-height:1;letter-spacing:0.05em;color:#ffffff\">Key point<\/div><div class=\"epb-box__body\">\n<p>Do not stop at \u201cwe added X bacteria.\u201d Strong differentiation comes from clearly stating <em>which function<\/em> you aim to influence (e.g., SCFA production, bile acid metabolism, suppression of putrefactive metabolites). Because the microbiome has broad functions\u2014sometimes called a \u201cforgotten organ\u201d\u2014it is critical to define \u201cwhat good means\u201d in functional terms and translate that into design choices.<\/p>\n<\/div><\/div>\n\n\n\n<h3 class=\"wp-block-heading\">2) Controlled fermentation (SCFAs)<\/h3>\n\n\n\n<p>SCFAs are microbial metabolites, and butyrate is particularly important as fuel for colonic epithelium. However, fermentation that is too rapid can cause gas and osmotic diarrhea\/soft stool.<\/p>\n\n\n\n<p>In development, the key is not simply \u201cincrease SCFAs,\u201d but rather <strong>control<\/strong>:<\/p>\n\n\n\n<ul class=\"wp-block-list is-style-list__border-bottom is-style-item__arrow has-dark-white-background-color has-background\">\n<li><strong>Control fermentation speed<\/strong> by adjusting solubility, particle size, viscosity, and inclusion level<\/li>\n\n\n\n<li><strong>Reduce bias\/peaks<\/strong> by blending multiple substrates instead of \u201cdumping\u201d one fast-fermenting ingredient<\/li>\n<\/ul>\n\n\n\n<p>If you include large amounts of highly fermentable soluble fiber, fermentation can accelerate in the colon and lead to gas and soft stool. Combining with less fermentable insoluble fiber (e.g., cellulose) can slow fermentation and improve stool formation.<\/p>\n\n\n\n<p>Empirically, blending fibers with different fermentation rates (fast \u2192 medium \u2192 slow) tends to stabilize stool.<\/p>\n\n\n\n<p>Studies in dogs also report that appropriate levels of FOS can increase SCFAs (including butyrate), increase Lactobacillus\/Bifidobacterium, and reduce pH. But excessive fiber can reduce digestibility and increase stool volume. The \u201cwhy\u201d of fiber inclusion must be explicit (stool forming, fermentation support, calorie control, etc.).<\/p>\n\n\n\n<div class=\"epb-linkcard is-style-epb-radius__0 is-style-epb-hover__floating wp-block-emanon-premium-blocks-linkcard epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" style=\"--epb-linkcard-arrow-size:16px\"><div class=\"epb-linkcard_label icon-edit\" data-fontweight=\"normal\" style=\"font-size:12px;letter-spacing:0.15em\">Related article<\/div><a class=\"epb-linkcard_link\" href=\"https:\/\/first-reach.org\/en\/contents\/short-chain-fatty-acids-petfood\/\" target=\"_blank\" rel=\"noopener noreferrer\"><div class=\"epb-linkcard_inner epb-arrow-effect-right is-style-epb-arrow__01\" style=\"padding-top:16px;padding-bottom:16px;padding-left:24px;border-style:solid;border-top-width:0;border-bottom-width:2px;border-left-width:0;border-right-width:0;border-color:#e5e7e8\"><div class=\"epb-linkcard_heading\"><div class=\"epb-linkcard_title\" data-fontweight=\"normal\" style=\"--epb-title-font-sp:16px;--epb-title-font-tablet:16px;--epb-title-font-pc:16px;letter-spacing:0.04em;color:#333333\">Utilization of Short-Chain Fatty Acids in Dog and Cat Pet Food<\/div><\/div><\/div><\/a><\/div>\n\n\n\n<h3 class=\"wp-block-heading\">3) Mucosal barrier (mucus layer)<\/h3>\n\n\n\n<p>The mucosal barrier is a coordinated \u201cbreakwater\u201d formed by the mucus layer, epithelial cells, tight junctions, and immune cells. Especially in the colon, mucus helps prevent pathogen invasion, while immune cells beneath the epithelium help maintain microbial homeostasis.<\/p>\n\n\n\n<p>Rather than claiming \u201cthis ingredient strengthens the barrier,\u201d a more fundamental strategy is to <strong>avoid conditions that damage the barrier<\/strong> (over-fermentation, putrefaction, irritants).<\/p>\n\n\n\n<p>For example, butyrate supports epithelial energy needs and contributes to tight-junction maintenance. Beneficial microbial metabolites such as acetate and butyrate have been reported to support epithelial barrier integrity. Conversely, excessive translocation of endotoxins (e.g., LPS) may contribute to systemic inflammation, making barrier impairment something to avoid.<\/p>\n\n\n\n<p>From a development perspective: prevent excessive fermentation\/putrefaction that irritates the mucosa, while using controlled fermentable substrates or postbiotic approaches that can \u201cnourish\u201d the epithelium gently.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">4) Gut immunity<\/h3>\n\n\n\n<p>The gut contains extensive GALT (gut-associated lymphoid tissue), one of the body\u2019s largest immune systems. Healthy function requires balance between <strong>immune tolerance<\/strong> (not overreacting) and <strong>appropriate defense<\/strong>.<\/p>\n\n\n\n<p>A commonly measured marker is <strong>IgA<\/strong>, a secretory antibody that blocks pathogen binding at mucosal surfaces and is often used as a marker of mucosal immune status.<\/p>\n\n\n\n<p>Some studies report changes in immune markers with probiotics. For example, Benyacoub et al. (2003) reported that supplementation with <em>Enterococcus faecium<\/em> SF68 increased fecal and serum IgA in puppies. The same study also reported enhanced vaccine antibody responses (IgG\/IgA) and increased B-cell proportions\u2014an example of probiotic-mediated immune modulation.<br>\u3000<\/p>\n\n\n\n<div class=\"epb-box epb-has-box-margin-item is-style-epb-border-headline\" style=\"--epb-box-padding-top:16px;--epb-box-padding-right:16px;--epb-box-padding-bottom:16px;--epb-box-padding-left:16px;--epb-box-margin-item:8px;--epb-box-padding-background-color:#ffffff;--epb-box-border-style:solid;--epb-box-border-color:#cf2e2e;--epb-box-border-width-top:2px;--epb-box-border-width-bottom:2px;--epb-box-border-width-left:2px;--epb-box-border-width-right:2px;--epb-box-radius:3px\"><div class=\"epb-box__headline icon-lightbulb \" data-fontweight=\"normal\" style=\"text-align:left;--epb-box-headline-background-color:#cf2e2e;--epb-font-sp:14px;--epb-font-tablet:14px;--epb-font-pc:16px;line-height:1;letter-spacing:0.05em;color:#ffffff\">Key point<\/div><div class=\"epb-box__body\">\n<p><br>Be cautious with the phrase \u201cboost immunity.\u201d Immunity is not \u201cthe higher the better,\u201d and excessive inflammation can be harmful. Practically, product messaging should focus on supporting <strong>immune balance<\/strong> and barrier function (e.g., \u201csupports a healthy immune balance and intestinal barrier maintenance\u201d).<\/p>\n<\/div><\/div>\n\n\n\n<h2 class=\"wp-block-heading\">Why gut health can influence the whole body<\/h2>\n\n\n\n<p>The gut is a hub that interacts with multiple organs and functions. As a result, improving gut environment may influence skin, brain, kidneys, and more\u2014often discussed as \u201cX\u2013gut axes.\u201d Below is an overview of four major axes, with mechanisms and evidence concepts.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Gut\u2013immune axis<\/h3>\n\n\n\n<p>Microbial metabolites (SCFAs, etc.) and barrier status can affect local immunity and systemic inflammatory signaling. Butyrate supports epithelial health and may contribute to controlled immune responses. Acetate and butyrate can inhibit pathogen growth via pH reduction and are suggested to influence immune regulation (e.g., regulatory T-cell induction, anti-inflammatory signaling).<\/p>\n\n\n\n<p>There are also veterinary reviews summarizing probiotic applications and evidence across use cases, including diarrhea management, allergy support, and stress modulation.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Gut\u2013skin axis<\/h3>\n\n\n\n<p>In canine atopic dermatitis (cAD), links to the gut microbiome have been discussed. Some trials report improved clinical scores and microbiome changes after probiotic supplementation.<\/p>\n\n\n\n<p>A Korean study (2025) reported that in 23 atopic dogs receiving probiotics for 16 weeks, symptom scores (CADESI-4 and pruritus index) improved significantly and microbial diversity increased. Dogs with greater diversity improvement also tended to have better skin outcomes.<\/p>\n\n\n\n<p>Earlier single-strain studies (e.g., <em>Lactobacillus rhamnosus<\/em> GG; Marsella et al., 2012) reported limited effects, but multi-strain probiotics and synbiotics have shown more promising results in later work.<br>\u3000<\/p>\n\n\n\n<div class=\"epb-box epb-has-box-margin-item is-style-epb-border-headline\" style=\"--epb-box-padding-top:16px;--epb-box-padding-right:16px;--epb-box-padding-bottom:16px;--epb-box-padding-left:16px;--epb-box-margin-item:8px;--epb-box-padding-background-color:#ffffff;--epb-box-border-style:solid;--epb-box-border-color:#cf2e2e;--epb-box-border-width-top:2px;--epb-box-border-width-bottom:2px;--epb-box-border-width-left:2px;--epb-box-border-width-right:2px;--epb-box-radius:3px\"><div class=\"epb-box__headline icon-lightbulb \" data-fontweight=\"normal\" style=\"text-align:left;--epb-box-headline-background-color:#cf2e2e;--epb-font-sp:14px;--epb-font-tablet:14px;--epb-font-pc:16px;line-height:1;letter-spacing:0.05em;color:#ffffff\">Key point<\/div><div class=\"epb-box__body\">\n<p>Skin outcomes are \u201cvisible value\u201d for consumers, so the story \u201cgut mechanism \u2192 skin outcome\u201d can strengthen product appeal. However, avoid treatment claims; use \u201csupports healthy skin,\u201d \u201chelps maintain skin condition,\u201d etc.<\/p>\n<\/div><\/div>\n\n\n\n<h3 class=\"wp-block-heading\">Gut\u2013brain axis<\/h3>\n\n\n\n<p>In dogs, some research suggests probiotics may influence behavior. One example is <em>Bifidobacterium longum<\/em> BL999 (a specific strain used by Nestl\u00e9 Purina), reported to improve anxiety-related behaviors. Purina markets this concept as the supplement \u201cCalming Care.\u201d<\/p>\n\n\n\n<p>Proposed mechanisms include microbe-derived neuroactive compounds (e.g., GABA), tryptophan-related metabolites (serotonin pathways), vagus nerve signaling, and modulation of stress responses such as cortisol. Inflammation and increased intestinal permeability may also affect brain function, as suggested in human\/animal models.<\/p>\n\n\n\n<p>However, behavioral outcomes are harder to measure and more variable. From a product perspective, it\u2019s often safer to frame benefits as \u201cdigestive stability supports comfortable daily life,\u201d rather than making strong \u201ccalming\u201d claims.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Gut\u2013kidney\/urinary axis<\/h3>\n\n\n\n<p>Interest is growing in the relationship between chronic kidney disease (CKD) and gut dysbiosis in dogs and cats (the \u201cgut\u2013kidney axis\u201d). Reviews suggest that dysbiosis may worsen kidney disease via microbe-derived uremic toxins and systemic inflammation, and that interventions targeting gut metabolism may help support CKD management.<\/p>\n\n\n\n<p>Microbial uremic toxins (e.g., indoxyl sulfate, p-cresol sulfate) have been reported to increase in CKD and may correlate with disease progression. There is also discussion of oxalate metabolism: in dogs, the presence of <em>Oxalobacter formigenes<\/em> (an oxalate-degrading gut bacterium) has been associated with reduced calcium oxalate stone risk in some studies.<br>\u3000<\/p>\n\n\n\n<div class=\"epb-box epb-has-box-margin-item is-style-epb-border-headline\" style=\"--epb-box-padding-top:16px;--epb-box-padding-right:16px;--epb-box-padding-bottom:16px;--epb-box-padding-left:16px;--epb-box-margin-item:8px;--epb-box-padding-background-color:#ffffff;--epb-box-border-style:solid;--epb-box-border-color:#cf2e2e;--epb-box-border-width-top:2px;--epb-box-border-width-bottom:2px;--epb-box-border-width-left:2px;--epb-box-border-width-right:2px;--epb-box-radius:3px\"><div class=\"epb-box__headline icon-lightbulb \" data-fontweight=\"normal\" style=\"text-align:left;--epb-box-headline-background-color:#cf2e2e;--epb-font-sp:14px;--epb-font-tablet:14px;--epb-font-pc:16px;line-height:1;letter-spacing:0.05em;color:#ffffff\">Key point<\/div><div class=\"epb-box__body\">\n<p><br>This is still an emerging area. In product design and messaging, urinary\/kidney care should primarily rely on established nutritional strategies (mineral balance, urine pH control, hydration). Gut-health elements should be positioned as supportive context\u2014\u201cas part of overall wellness,\u201d not as a primary therapeutic claim.<\/p>\n<\/div><\/div>\n\n\n\n<h2 class=\"wp-block-heading\">Effects that gut-health approaches may support<\/h2>\n\n\n\n<p>Gut involvement is plausible across many conditions, but disease causes are multifactorial. Here we separate what research suggests from what is realistically targetable in product development and safe communication.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Whole-body health: immune balance, inflammation, allergy<\/h3>\n\n\n\n<p><strong>Dogs:<\/strong> Some probiotic studies show changes in IgA, vaccine antibody responses, and inflammatory markers.<\/p>\n\n\n\n<p><strong>Cats:<\/strong> While fewer studies exist, some work suggests probiotics may help maintain microbial stability under stressors (e.g., antibiotics). A study (Torres-Henderson et al., 2017) reported that SF68 helped reduce microbiome disruption and also suggested fewer chronic feline herpesvirus symptoms over time.<\/p>\n\n\n\n<p>For development and communication, safer language is \u201csupports intestinal barrier function and a healthy immune balance,\u201d rather than \u201cboosts immunity.\u201d<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">GI signs: diarrhea, constipation, gas, stool quality<\/h3>\n\n\n\n<p>The most direct and consumer-visible outcome is <strong>stool quality<\/strong>. Many digestive-support products focus on this.<\/p>\n\n\n\n<p>Evidence examples include synbiotic\/probiotic use in chronic diarrhea management and antibiotic-associated diarrhea, with improvements in stool scoring and owner-reported outcomes in some studies.<\/p>\n\n\n\n<p>From a development standpoint, stool is also easy to quantify via standardized scoring systems (e.g., Purina 7-point fecal score; normal often around 2\u20133).<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Behavior\/mental state: stress, anxiety, sleep<\/h3>\n\n\n\n<p>This is a growing research area, but measurement and reproducibility are challenging. From a product standpoint, it\u2019s generally safer to keep messaging modest and indirect.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Skin\/coat: dermatitis, coat gloss, barrier maintenance<\/h3>\n\n\n\n<p>Evidence is accumulating in dogs, especially for atopic dermatitis and probiotic interventions, though results vary by strain and study design. In cats, evidence is thinner; practical entry points often focus on stool comfort and hairball-related issues, with skin\/coat positioned as a secondary benefit.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Kidney\/urinary: potential supportive benefits<\/h3>\n\n\n\n<p>Some early studies suggest gut-targeted interventions may affect uremic markers, but the field is still developing. Messaging should remain conservative and supportive.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">From concept to product: practical formulation and process considerations<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Digestibility-first design<\/h3>\n\n\n\n<p>A common failure mode is: \u201cWe added gut-health ingredients (fiber\/probiotics), but stools got softer.\u201d In many cases, the root cause is increased undigested flow into the colon\u2014triggering fermentation\/putrefaction instability.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">Recommended order of operations<\/h4>\n\n\n\n<ol class=\"wp-block-list is-style-item__num--border\">\n<li><strong>Improve raw-material digestibility:<\/strong><br>Choose high-quality protein sources; avoid over-reliance on high-ash meals. Consider hydrolysis or enzyme processing when appropriate. In cats (high-protein requirement), protein digestibility strongly drives stool quality.<\/li>\n\n\n\n<li><strong>Optimize processing conditions:<\/strong><br>In extrusion, adjust temperature\/shear\/moisture to achieve appropriate starch gelatinization and controlled protein denaturation. Excessive heat is not automatically better; over-denaturation can reduce enzymatic digestibility. Manage drying to avoid scorching, and balance post-extrusion fat coating for palatability\/energy without triggering fat-related loose stool.<\/li>\n\n\n\n<li><strong>Starch gelatinization and particle size:<\/strong><br>Raw starch is less digestible and can behave like resistant starch, increasing colonic fermentation. Aim for adequate gelatinization (often cited as ideally high, e.g., &gt;90%), while tuning grind size for enzymatic accessibility. Avoid excessive micronization if blood-glucose response is a concern.<\/li>\n\n\n\n<li><strong>Cat-specific caution:<\/strong><br>Cats have limited hindgut fermentation capacity; design should assume \u201cfinish digestion in the small intestine.\u201d Excessive fiber strategies that may work in dogs can more easily cause soft stool in cats.<\/li>\n<\/ol>\n\n\n\n<p>First, ensure \u201cwhat should be digested\/absorbed in the small intestine is completed there.\u201d Then intentionally deliver targeted substrates (fiber\/oligosaccharides) to tune colonic fermentation.<\/p>\n\n\n\n<div class=\"epb-linkcard is-style-epb-radius__0 is-style-epb-hover__floating wp-block-emanon-premium-blocks-linkcard epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" style=\"--epb-linkcard-arrow-size:16px\"><div class=\"epb-linkcard_label icon-edit\" data-fontweight=\"normal\" style=\"font-size:12px;letter-spacing:0.15em\">Related article<\/div><a class=\"epb-linkcard_link\" href=\"https:\/\/first-reach.org\/en\/contents\/cat-food-recipes-for-adult-cats\/\" target=\"_blank\" rel=\"noopener noreferrer\"><div class=\"epb-linkcard_inner epb-arrow-effect-right is-style-epb-arrow__01\" style=\"padding-top:16px;padding-bottom:16px;padding-left:24px;border-style:solid;border-top-width:0;border-bottom-width:2px;border-left-width:0;border-right-width:0;border-color:#e5e7e8\"><div class=\"epb-linkcard_heading\"><div class=\"epb-linkcard_title\" data-fontweight=\"normal\" style=\"--epb-title-font-sp:16px;--epb-title-font-tablet:16px;--epb-title-font-pc:16px;letter-spacing:0.04em;color:#333333\">Design Guidelines for Dry Cat Food for Adult Cats<\/div><\/div><\/div><\/a><\/div>\n\n\n\n<h3 class=\"wp-block-heading\">Fiber is not \u201cadd or don\u2019t add\u201d\u2014it must be designed<\/h3>\n\n\n\n<p>Fiber includes insoluble and soluble types, and fermentation speed (fast vs slow) is also critical.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">Insoluble-leaning fibers:<\/h4>\n\n\n\n<p>Support stool formation and bulking; can help firm loose stool. Overuse may increase stool volume without providing fermentation benefits.<\/p>\n\n\n\n<p>Examples: cellulose, peanut hulls, some resistant dextrins (varies by type).<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">Soluble\/fermentable fibers:<\/h4>\n\n\n\n<p>Support SCFA production and can help with stool odor reduction (e.g., via pH reduction and ammonia capture mechanisms). Overuse can cause gas and soft stool.<\/p>\n\n\n\n<p>Examples: inulin, FOS, pectin fractions in beet pulp.<\/p>\n\n\n\n<div class=\"epb-linkcard is-style-epb-radius__0 is-style-epb-hover__floating wp-block-emanon-premium-blocks-linkcard epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" style=\"--epb-linkcard-arrow-size:16px\"><div class=\"epb-linkcard_label icon-edit\" data-fontweight=\"normal\" style=\"font-size:12px;letter-spacing:0.15em\">Related article<\/div><a class=\"epb-linkcard_link\" href=\"https:\/\/first-reach.org\/en\/contents\/inulin-prebiotics-petfood-dog-cat\/\" target=\"_blank\" rel=\"noopener noreferrer\"><div class=\"epb-linkcard_inner epb-arrow-effect-right is-style-epb-arrow__01\" style=\"padding-top:16px;padding-bottom:16px;padding-left:24px;border-style:solid;border-top-width:0;border-bottom-width:2px;border-left-width:0;border-right-width:0;border-color:#e5e7e8\"><div class=\"epb-linkcard_heading\"><div class=\"epb-linkcard_title\" data-fontweight=\"normal\" style=\"--epb-title-font-sp:16px;--epb-title-font-tablet:16px;--epb-title-font-pc:16px;letter-spacing:0.04em;color:#333333\">Practical Considerations for Using Inulin in Dog and Cat Pet Food Development<\/div><\/div><\/div><\/a><\/div>\n\n\n\n<h4 class=\"wp-block-heading\">Blending strategy:<\/h4>\n\n\n\n<p>Use blends to create a \u201cfermentation gradient\u201d: fast (e.g., FOS) + medium (e.g., beet pulp) + slow (e.g., cellulose). This approach often stabilizes stool by avoiding fermentation spikes while supporting SCFA production.<\/p>\n\n\n\n<p>Define the purpose clearly (firm stool, promote fermentation, weight management, etc.) and manage trade-offs (digestibility, palatability, energy density).<\/p>\n\n\n\n<div class=\"epb-linkcard is-style-epb-radius__0 is-style-epb-hover__floating wp-block-emanon-premium-blocks-linkcard epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" style=\"--epb-linkcard-arrow-size:16px\"><div class=\"epb-linkcard_label icon-edit\" data-fontweight=\"normal\" style=\"font-size:12px;letter-spacing:0.15em\">Related article<\/div><a class=\"epb-linkcard_link\" href=\"https:\/\/first-reach.org\/en\/contents\/fiber-in-dog-foods\/\" target=\"_blank\" rel=\"noopener noreferrer\"><div class=\"epb-linkcard_inner epb-arrow-effect-right is-style-epb-arrow__01\" style=\"padding-top:16px;padding-bottom:16px;padding-left:24px;border-style:solid;border-top-width:0;border-bottom-width:2px;border-left-width:0;border-right-width:0;border-color:#e5e7e8\"><div class=\"epb-linkcard_heading\"><div class=\"epb-linkcard_title\" data-fontweight=\"normal\" style=\"--epb-title-font-sp:16px;--epb-title-font-tablet:16px;--epb-title-font-pc:16px;letter-spacing:0.04em;color:#333333\">The Role and Benefits of Dietary Fiber in Dog Food<\/div><\/div><\/div><\/a><\/div>\n\n\n\n<h3 class=\"wp-block-heading\">Choosing between \u201cbiotics\u201d: how to use them in pet food<\/h3>\n\n\n\n<h4 class=\"wp-block-heading\">Prebiotics (substrates for microbes):<\/h4>\n\n\n\n<p>Oligosaccharides and fibers that feed beneficial microbes. Generally stable and easy to use in dry foods. Some can work at low inclusion levels.<\/p>\n\n\n\n<div class=\"epb-linkcard is-style-epb-radius__0 is-style-epb-hover__floating wp-block-emanon-premium-blocks-linkcard epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" style=\"--epb-linkcard-arrow-size:16px\"><div class=\"epb-linkcard_label icon-edit\" data-fontweight=\"normal\" style=\"font-size:12px;letter-spacing:0.15em\">Related article<\/div><a class=\"epb-linkcard_link\" href=\"https:\/\/first-reach.org\/en\/contents\/about-prebiotics\/\" target=\"_blank\" rel=\"noopener noreferrer\"><div class=\"epb-linkcard_inner epb-arrow-effect-right is-style-epb-arrow__01\" style=\"padding-top:16px;padding-bottom:16px;padding-left:24px;border-style:solid;border-top-width:0;border-bottom-width:2px;border-left-width:0;border-right-width:0;border-color:#e5e7e8\"><div class=\"epb-linkcard_heading\"><div class=\"epb-linkcard_title\" data-fontweight=\"normal\" style=\"--epb-title-font-sp:16px;--epb-title-font-tablet:16px;--epb-title-font-pc:16px;letter-spacing:0.04em;color:#333333\">7 Prebiotic-Rich Ingredients to Use in Dog and Cat Food Development<\/div><\/div><\/div><\/a><\/div>\n\n\n\n<h4 class=\"wp-block-heading\">Probiotics (live microbes):<\/h4>\n\n\n\n<p>Strain-specific and potentially strong, but stability is challenging in extrusion and during shelf life. Special technologies (e.g., post-process coating) may be required. Spore-formers (e.g., <em>Bacillus<\/em>) are more heat-resistant, but evidence can be thinner than for some lactic acid bacteria.<\/p>\n\n\n\n<div class=\"epb-linkcard is-style-epb-radius__0 is-style-epb-hover__floating wp-block-emanon-premium-blocks-linkcard epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" style=\"--epb-linkcard-arrow-size:16px\"><div class=\"epb-linkcard_label icon-edit\" data-fontweight=\"normal\" style=\"font-size:12px;letter-spacing:0.15em\">Related article<\/div><a class=\"epb-linkcard_link\" href=\"https:\/\/first-reach.org\/en\/contents\/about-probiotics\/\" target=\"_blank\" rel=\"noopener noreferrer\"><div class=\"epb-linkcard_inner epb-arrow-effect-right is-style-epb-arrow__01\" style=\"padding-top:16px;padding-bottom:16px;padding-left:24px;border-style:solid;border-top-width:0;border-bottom-width:2px;border-left-width:0;border-right-width:0;border-color:#e5e7e8\"><div class=\"epb-linkcard_heading\"><div class=\"epb-linkcard_title\" data-fontweight=\"normal\" style=\"--epb-title-font-sp:16px;--epb-title-font-tablet:16px;--epb-title-font-pc:16px;letter-spacing:0.04em;color:#333333\">Probiotics for Supporting Gut Health in Dogs and Cats: Benefits and Side Effects<\/div><\/div><\/div><\/a><\/div>\n\n\n\n<h4 class=\"wp-block-heading\">Synbiotics (probiotic + prebiotic):<\/h4>\n\n\n\n<p>Combining live microbes with substrates to support them. Offers good product-design flexibility and can align with clinical \u201cwhen GI is unstable\u201d messaging.<\/p>\n\n\n\n<div class=\"epb-linkcard is-style-epb-radius__0 is-style-epb-hover__floating wp-block-emanon-premium-blocks-linkcard epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" style=\"--epb-linkcard-arrow-size:16px\"><div class=\"epb-linkcard_label icon-edit\" data-fontweight=\"normal\" style=\"font-size:12px;letter-spacing:0.15em\">Related article<\/div><a class=\"epb-linkcard_link\" href=\"https:\/\/first-reach.org\/en\/contents\/synbiotics-for-pets\/\" target=\"_blank\" rel=\"noopener noreferrer\"><div class=\"epb-linkcard_inner epb-arrow-effect-right is-style-epb-arrow__01\" style=\"padding-top:16px;padding-bottom:16px;padding-left:24px;border-style:solid;border-top-width:0;border-bottom-width:2px;border-left-width:0;border-right-width:0;border-color:#e5e7e8\"><div class=\"epb-linkcard_heading\"><div class=\"epb-linkcard_title\" data-fontweight=\"normal\" style=\"--epb-title-font-sp:16px;--epb-title-font-tablet:16px;--epb-title-font-pc:16px;letter-spacing:0.04em;color:#333333\">Effects and Practical Applications of Synbiotics in Dogs and Cats<\/div><\/div><\/div><\/a><\/div>\n\n\n\n<h4 class=\"wp-block-heading\">Postbiotics (inactivated microbes and\/or microbial metabolites):<\/h4>\n\n\n\n<p>Growing interest due to processing and storage stability; easier to incorporate into dry foods. In pet food, postbiotic-focused papers and IP analyses are increasing, and some studies suggest benefits related to barrier and immune balance. This category is becoming more prominent partly because \u201clive probiotics\u201d are hard to guarantee through manufacturing and distribution.<\/p>\n\n\n\n<div class=\"epb-linkcard is-style-epb-radius__0 is-style-epb-hover__floating wp-block-emanon-premium-blocks-linkcard epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" style=\"--epb-linkcard-arrow-size:16px\"><div class=\"epb-linkcard_label icon-edit\" data-fontweight=\"normal\" style=\"font-size:12px;letter-spacing:0.15em\">Related article<\/div><a class=\"epb-linkcard_link\" href=\"https:\/\/first-reach.org\/en\/contents\/about-postbiotics\/\" target=\"_blank\" rel=\"noopener noreferrer\"><div class=\"epb-linkcard_inner epb-arrow-effect-right is-style-epb-arrow__01\" style=\"padding-top:16px;padding-bottom:16px;padding-left:24px;border-style:solid;border-top-width:0;border-bottom-width:2px;border-left-width:0;border-right-width:0;border-color:#e5e7e8\"><div class=\"epb-linkcard_heading\"><div class=\"epb-linkcard_title\" data-fontweight=\"normal\" style=\"--epb-title-font-sp:16px;--epb-title-font-tablet:16px;--epb-title-font-pc:16px;letter-spacing:0.04em;color:#333333\">An Alternative to Probiotics? The Benefits of Postbiotics in Pet Food Development<\/div><\/div><\/div><\/a><\/div>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p>What matters is not \u201cwhich one,\u201d but \u201chow it is used\u201d given your product form (dry, wet, freeze-dried), process constraints, and the claim level you want to support.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Barrier\/immune-support ingredients: use with careful positioning<\/h3>\n\n\n\n<p>Barrier\/immune messaging is higher-risk if overstated. The practical approach is:<\/p>\n\n\n\n<ul class=\"wp-block-list is-style-list__border-bottom is-style-item__arrow has-dark-white-background-color has-background\">\n<li>First, design a gut environment that is hard to irritate (avoid over-fermentation\/putrefaction; reduce undigested flow).<\/li>\n\n\n\n<li>Then add supportive ingredients for mucosal immune maintenance as \u201creinforcement,\u201d not the main story.<\/li>\n<\/ul>\n\n\n\n<p>Examples include yeast beta-glucans, nucleotides, fermented extracts, and functional peptides. Some canine studies suggest immune-marker changes and vaccine response effects, but mechanisms are not always simple or consistent. For product communication, conservative phrasing such as \u201csupports barrier function and healthy immune balance\u201d is typically safer than strong claims.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Avoid the \u201ceverything plus the kitchen sink\u201d problem<\/h3>\n\n\n\n<p>Gut-health formulas always involve trade-offs:<\/p>\n\n\n\n<ul class=\"wp-block-list is-style-list__border-bottom is-style-item__arrow has-dark-white-background-color has-background\">\n<li>Higher fermentable substrate \u2192 potentially more SCFAs <strong>but<\/strong> higher gas\/soft stool risk<\/li>\n\n\n\n<li>Higher total fiber \u2192 easier stool formation\/weight management <strong>but<\/strong> lower palatability and energy density<\/li>\n\n\n\n<li>Higher protein \u2192 supports feline needs and lean mass <strong>but<\/strong> increases putrefaction risk if digestibility cannot keep up<\/li>\n<\/ul>\n\n\n\n<p>The development team should be able to explain <em>how the formulation resolves these trade-offs<\/em>, supported by rationale and data.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">How to validate gut-health effects: what to measure<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Priority KPIs: stool score, frequency, gas, odor<\/h3>\n\n\n\n<p>The strongest\u2014and most practical\u2014KPI for gut-health products is <strong>stool<\/strong>.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">Implementation examples<\/h4>\n\n\n\n<ul class=\"wp-block-list is-style-item__checkmark--square has-dark-white-background-color has-background\">\n<li><strong>Fecal score:<\/strong> Use a standardized scale such as Purina\u2019s 7-point system; ideal often around 2\u20133. Record daily and compare averages.<\/li>\n\n\n\n<li><strong>Defecation frequency:<\/strong> Track per day; too high suggests intolerance or excessive fiber; too low suggests constipation risk.<\/li>\n\n\n\n<li><strong>Gas:<\/strong> Use pre-defined qualitative categories (high\/normal\/low) scored by caretakers or veterinarians.<\/li>\n\n\n\n<li><strong>Odor:<\/strong> Sensory evaluation or owner questionnaires under standardized conditions.<\/li>\n<\/ul>\n\n\n\n<p>If you can show \u201cstool moved into the ideal range within 2 weeks,\u201d that is both scientifically manageable and highly persuasive in the market.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">SCFAs, pH, and putrefactive metabolites<\/h3>\n\n\n\n<p>Chemical markers in feces or intestinal contents can strengthen mechanistic credibility.<\/p>\n\n\n\n<ul class=\"wp-block-list is-style-item__checkmark--square has-dark-white-background-color has-background\">\n<li><strong>SCFAs (acetate\/propionate\/butyrate):<\/strong> Often measured by GC-MS; interpret using balance and context, not \u201chigher is always better.\u201d<\/li>\n\n\n\n<li><strong>Branched-chain fatty acids (BCFAs):<\/strong> Often reflect protein fermentation; increases can indicate excess undigested protein reaching the colon.<\/li>\n\n\n\n<li><strong>pH:<\/strong> Lower pH can indicate fermentation; extremes can indicate risk (very low may align with diarrhea risk; very high can suggest putrefactive dominance).<\/li>\n\n\n\n<li><strong>Ammonia, indoles, phenols:<\/strong> Putrefactive markers; reductions support a \u201cless putrefactive\u201d shift.<\/li>\n<\/ul>\n\n\n\n<div class=\"epb-box epb-has-box-margin-item is-style-epb-border-headline\" style=\"--epb-box-padding-top:16px;--epb-box-padding-right:16px;--epb-box-padding-bottom:16px;--epb-box-padding-left:16px;--epb-box-margin-item:8px;--epb-box-padding-background-color:#ffffff;--epb-box-border-style:solid;--epb-box-border-color:#cf2e2e;--epb-box-border-width-top:2px;--epb-box-border-width-bottom:2px;--epb-box-border-width-left:2px;--epb-box-border-width-right:2px;--epb-box-radius:3px\"><div class=\"epb-box__headline icon-lightbulb \" data-fontweight=\"normal\" style=\"text-align:left;--epb-box-headline-background-color:#cf2e2e;--epb-font-sp:14px;--epb-font-tablet:14px;--epb-font-pc:16px;line-height:1;letter-spacing:0.05em;color:#ffffff\">Key point<\/div><div class=\"epb-box__body\">\n<p>Do not judge a single metric in isolation. Look for combined patterns: e.g., SCFAs appropriately supported, pH stabilized, and putrefactive markers reduced.<\/p>\n<\/div><\/div>\n\n\n\n<h3 class=\"wp-block-heading\">Barrier, immunity (IgA), and inflammation<\/h3>\n\n\n\n<p>These add credibility but are more research-intensive.<\/p>\n\n\n\n<ul class=\"wp-block-list is-style-item__checkmark--square has-dark-white-background-color has-background\">\n<li><strong>IgA:<\/strong> Serum or fecal IgA via ELISA (interpret carefully; context matters)<\/li>\n\n\n\n<li><strong>Inflammation markers:<\/strong> Fecal calprotectin, serum CRP, cytokines (IL-6, TNF-\u03b1, etc.)<\/li>\n\n\n\n<li><strong>Intestinal permeability:<\/strong> Marker tests (e.g., lactulose\/mannitol ratio), typically more advanced<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Microbiome analysis: important caveats<\/h3>\n\n\n\n<ul class=\"wp-block-list is-style-item__checkmark--square has-dark-white-background-color has-background\">\n<li>16S profiling shows composition but not direct function; metagenomics is richer but costly.<\/li>\n\n\n\n<li>Feces reflects luminal microbiota, not mucosa-adherent communities.<\/li>\n\n\n\n<li>The field is shifting from \u201cwhich bacteria\u201d to \u201cwhat functions\/metabolites.\u201d Pair microbiome data with SCFAs and metabolite data to build a stronger story.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">Western market trends and what\u2019s next (research \u00d7 market)<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Why demand is growing<\/h3>\n\n\n\n<p>In the US and Europe, \u201cdigestion,\u201d \u201cgut,\u201d and \u201cmicrobiome\u201d have become established value themes within broader premiumization and wellness trends. Preventive mindsets are also spreading: maintaining daily digestive comfort through food is increasingly valued.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">What sells well: typical successful positioning<\/h3>\n\n\n\n<p>Gut health is often strongest when connected to broader needs:<\/p>\n\n\n\n<ul class=\"wp-block-list is-style-item__arrow has-dark-white-background-color has-background\">\n<li><strong>Digestive comfort:<\/strong> stool quality, gas, and odor<\/li>\n\n\n\n<li><strong>Skin\/coat:<\/strong> \u201cgut\u2013skin\u201d narrative for sensitive-skin products<\/li>\n\n\n\n<li><strong>Mental\/behavioral support:<\/strong> cautiously positioned, often indirectly<\/li>\n\n\n\n<li><strong>Senior health:<\/strong> gut as part of multi-support concepts (immune, muscle, kidney)<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Likely research trends<\/h3>\n\n\n\n<ul class=\"wp-block-list is-style-item__checkmark--square has-dark-white-background-color has-background\">\n<li>Expansion of gut\u2013brain studies (stress, anxiety, cognition)<\/li>\n\n\n\n<li>Growth in gut\u2013kidney research (uremic toxins, inflammation, metabolism)<\/li>\n\n\n\n<li>Continued shift from \u201cbacteria names\u201d to \u201cmetabolites\/functions\u201d<\/li>\n\n\n\n<li>Exploration of next-generation probiotics (with safety and manufacturing hurdles\u2014postbiotics may expand first)<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Likely market trends<\/h3>\n\n\n\n<ul class=\"wp-block-list is-style-item__checkmark--square has-dark-white-background-color has-background\">\n<li><strong>Personalization:<\/strong> microbiome tests linked to custom diets\/subscriptions<\/li>\n\n\n\n<li><strong>Clean label:<\/strong> preference for familiar ingredient names (pumpkin, sweet potato) over complex additive terminology<\/li>\n\n\n\n<li><strong>Less \u201clive probiotic\u201d emphasis:<\/strong> more postbiotic or fermented-ingredient positioning due to stability\/expectation gaps<\/li>\n\n\n\n<li><strong>Sustainability synergy:<\/strong> many prebiotic fibers are plant-derived and can align with eco-focused messaging<\/li>\n<\/ul>\n\n\n\n<p>Overall, gut-health is moving from \u201ca fad\u201d to a long-term category, supported by expanding science and increasing consumer literacy. For R&amp;D leaders, the advantage comes from translating up-to-date research into coherent, manufacturable product designs with measurable outcomes.<\/p>\n\n\n\n<div class=\"epb-linkcard is-style-epb-radius__0 is-style-epb-hover__floating wp-block-emanon-premium-blocks-linkcard epb-margin-top__default epb-margin-top__default-sp epb-margin-top__default-tablet\" style=\"--epb-linkcard-arrow-size:16px\"><div class=\"epb-linkcard_label icon-edit\" data-fontweight=\"normal\" style=\"font-size:12px;letter-spacing:0.15em\">Related article<\/div><a class=\"epb-linkcard_link\" href=\"https:\/\/first-reach.org\/en\/contents\/about-postbiotics\/\" target=\"_blank\" rel=\"noopener noreferrer\"><div class=\"epb-linkcard_inner epb-arrow-effect-right is-style-epb-arrow__01\" style=\"padding-top:16px;padding-bottom:16px;padding-left:24px;border-style:solid;border-top-width:0;border-bottom-width:2px;border-left-width:0;border-right-width:0;border-color:#e5e7e8\"><div class=\"epb-linkcard_heading\"><div class=\"epb-linkcard_title\" data-fontweight=\"normal\" style=\"--epb-title-font-sp:16px;--epb-title-font-tablet:16px;--epb-title-font-pc:16px;letter-spacing:0.04em;color:#333333\">An Alternative to Probiotics? The Benefits of Postbiotics in Pet Food Development<\/div><\/div><\/div><\/a><\/div>\n\n\n\n<h4 class=\"wp-block-heading\">\u53c2\u8003\u6587\u732e<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>He, X. et al. <em>Characteristics of the Digestive Tract of Dogs and Cats<\/em>. Advances in Experimental Medicine and Biology, 2024, pp. 15\u201338.<\/li>\n\n\n\n<li>Mondo, E. et al. <em>Role of gut microbiota in dog and cat\u2019s health and diseases<\/em>. Veterinary World, 2019.<\/li>\n\n\n\n<li>Xu, J. et al. <em>High protein diet and canine gut microbiota<\/em>. BMC Veterinary Research, 2017.<\/li>\n\n\n\n<li>Isaiah, A. et al. <em>Fecal short-chain fatty acids and dysbiosis in dogs with chronic enteropathy<\/em>. Journal of Veterinary Internal Medicine, 2019.<\/li>\n\n\n\n<li>Benyacoub, J. et al. <em>Supplementation of Enterococcus faecium (SF68) stimulates immune functions in young dogs<\/em>. The Journal of Nutrition, 2003.<\/li>\n\n\n\n<li>Song, X. et al. <em>Probiotics ameliorate atopic dermatitis by modulating gut microbiota in dogs<\/em>. BMC Veterinary Research, 2025.<\/li>\n\n\n\n<li>Purina Institute. <em>Stress-Related Behavioral Disorders in Pets<\/em>. 2021.<\/li>\n\n\n\n<li>Mondo, E. et al. <em>Gut-Brain Axis Impact on Canine Anxiety Disorders<\/em>. Animals, 2023.<\/li>\n\n\n\n<li>Klinmalai, P. et al. <em>Probiotics in Pet Food: A Decade of Research, Patents, and Market Trends<\/em>. Foods, 2025.<\/li>\n\n\n\n<li>Kenny, J. et al. <em>Presence of Oxalobacter formigenes in dogs and calcium oxalate urolithiasis<\/em>. Urological Research, 2012.<\/li>\n\n\n\n<li>Royal Canin. <em>The Feline Gut-Kidney Axis: food for thought<\/em>. 2023.<\/li>\n\n\n\n<li>Torres-Henderson, C. et al. <em>Effect of Enterococcus faecium SF68 on gastrointestinal signs and the microbiome in antibiotic-treated cats<\/em>. Topics in Companion Animal Medicine, 2017.<\/li>\n\n\n\n<li>Hart, M. L. et al. <em>Open-label trial of a multi-strain synbiotic in cats with chronic diarrhea<\/em>. Journal of Feline Medicine and Surgery, 2012.<\/li>\n\n\n\n<li>Apper, E. <em>Integrating postbiotics in pet food and the brain\u2013gut connection<\/em>. AgroFOOD Industry Hi Tech, 2024.<\/li>\n\n\n\n<li>Pumpkin Care. <em>Ultimate Guide to Dog Poop Health<\/em>. 2025.<\/li>\n\n\n\n<li>Laboklin. <em>Faecal Biomarkers in Feline and Canine Chronic Enteropathies<\/em>. 2023.<\/li>\n\n\n\n<li>Phillips-Donaldson, D. <em>Pet probiotics rising, driven by health focus<\/em>. PetfoodIndustry.com, 2024.<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>In pet food development, \u201cgut health\u201d is no longer a simple matter of \u201cadding oligosaccharides or lactic acid bacteria.\u201d The gut is not only the site of nutrient digestion and absorption\u2014it is increasingly viewed as a functional organ that can influence the whole body through fermentation (microbial metabolism), the mucosal barrier, and gut-associated immunity, potentially [&hellip;]<\/p>\n","protected":false},"author":5,"featured_media":45753,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[12],"tags":[],"class_list":["post-45749","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-ingredients-formulation"],"_links":{"self":[{"href":"https:\/\/first-reach.org\/en\/wp-json\/wp\/v2\/posts\/45749","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/first-reach.org\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/first-reach.org\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/first-reach.org\/en\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/first-reach.org\/en\/wp-json\/wp\/v2\/comments?post=45749"}],"version-history":[{"count":49,"href":"https:\/\/first-reach.org\/en\/wp-json\/wp\/v2\/posts\/45749\/revisions"}],"predecessor-version":[{"id":48076,"href":"https:\/\/first-reach.org\/en\/wp-json\/wp\/v2\/posts\/45749\/revisions\/48076"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/first-reach.org\/en\/wp-json\/wp\/v2\/media\/45753"}],"wp:attachment":[{"href":"https:\/\/first-reach.org\/en\/wp-json\/wp\/v2\/media?parent=45749"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/first-reach.org\/en\/wp-json\/wp\/v2\/categories?post=45749"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/first-reach.org\/en\/wp-json\/wp\/v2\/tags?post=45749"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}