From Chihuahua to Saint-Bernard: how did digestion and microbiota evolve with dog sizes

Health and well-being of dogs are of paramount importance to their owners. Digestion plays a key role in dog health, involving physicochemical, mechanical and microbial actors. However, decades of breeding selection led to various dog sizes associated with different digestive physiology and disease sensitivity. Developing new products requires the consideration of all the multi-faceted aspects of canine digestion, the evaluation of food digestibility, drug release and absorption in the gut. This review paper provides an exhaustive literature survey on canine digestive physiology, focusing on size effect on anatomy and digestive parameters, with graphical representation of data classified as “small”, “medium” and “large” dogs. Despite the huge variability between protocols and animals, interesting size effects on gastrointestinal physiology were highlighted, mainly related to the colonic compartment. Colonic measurements, transit time permeability, fibre degradation, faecal short-chain fatty acid concentration and faecal water content increase while faecal bile acid concentration decreases with body size. A negative correlation between body weight and Proteobacteria relative abundance was observed suggesting an effect of dog body size on faecal microbiota. This paper gathers helpful in vivo data for academics and industrials and supports the development of new food and pharma products to move towards canine personalized nutrition and health

Short-chain fructo-oligosaccharides supplementation to suckling piglets : assessment of pre- and post-weaning performance and gut health

Farmers face difficulties in redeeming their investment in larger litter sizes since this comes with larger litter heterogenicity, lower litter resilience and risk of higher mortality. Dietary oligosaccharides, given to the sow, proved beneficial for the offspring's performance. However, giving oligosaccharides to the suckling piglet is poorly explored. Therefore, this field trial studied the effect of dietary short-chain fructo-oligosaccharides (scFOS; 1g/day; drenched) supplementation to low (LBW, lower quartile), normal (NBW, two intermediate quartiles) and high (HBW, upper quartile) birth weight piglets from birth until 7 or 21 days of age. Performance parameters, gut microbiome and short-chain fatty acids profile of feces and digesta were assessed at birth (d 0), d 7, weaning (d 21.5) and 2 weeks post-weaning (d 36.5). Additional parameters reflecting gut health (intestinal integrity and morphology, mucosal immune system) were analysed at d 36.5. Most parameters changed with age or differed with the piglet's birth weight. Drenching with scFOS increased body weight by 1 kg in NBW suckling piglets and reduced the post-weaning mortality rate by a 100%. No clear difference in the IgG level, the microbiota composition and fermentative activity between the treatment groups was observed. Additionnally, intestinal integrity, determined by measuring intestinal permeability and regenerative capacity, was similar between the treatment groups. Also, intestinal architecture (villus lenght, crypt depth) was not affected by scFOS supplementation. The density of intra-epithelial lymphocytes and the expression profiles (real-time qPCR) for immune system-related genes (IL-10, IL-1ss, IL-6, TNF alpha and IFN gamma) were used to assess mucosal immunity. Only IFN gamma expression, was upregulated in piglets that received scFOS for 7 days. The improved body weight and the reduced post-weaning mortality seen in piglets supplemented with scFOS support the view that scFOS positively impact piglet's health and resilience. However, the modes of action for these effects are not yet fully elucidated and its potential to improve other performance parameters needs further investigation

Equilibre de la ration et homéostasie acido-basique chez la vache laitière forte productrice (rôle de la balance alimentaire en cations et en anions, de la teneur en protéines et en énergie rapidement dégradable de la ration)

En élevage bovin laitier, les pratiques actuelles conduisent souvent à l'appartion d'états de sub-acidose responsables de pertes économiques. L'utilisation de la balance alimentaire en Cations et en Anions (BACA) représente une pistse intéressante pour limiter les risques, puisque l'absorption des catins se fait contre des protons à l'inverse de celle des anions qui se fait contre HCO3-. Les objectifs ont été de 1) définir les recommandations en faisant l'hypothèse que les réponses pouvaient être modulées selon la teneur en énergie rapidement dégradable (risque d'acidose ruminale) et en PDIE des ratios, les protéines pouvant avoir un rôle tampon et 2) décrire les mécanismes de régulation sous jacents. Quatre essais ont été conduits dans lesquels des BACA de 0 à 300 mEq/kg MS ont été croisées avec deux teneurs en protéines (90 g à 115 g PDIE/UFL) (essai 3). Les BACA ont été modulées par apport de NaCO3- de NH4Cl et de Na2PO4. L'accroissement de la BACA a accru les quantités ingérées et la production de lait 4 %. Ces effets se mettent en place dès la première semaine des traitements et sont pérennes (au moins jusqu'à 12 semaines). Les mécanismes impliqués restent encore à préciser mais les résultats semblent s'expliquer en partie par un effet de régulation de l'homéostasie acido-basique du sang sans que l'on puisse exclure un effet direct dans le rumen. Les flux d'ions forts sont essentiellement régulés par l'excrétion rénale et le pH de l'urine semble être un bon indicateur de la BACA. Ces résultats montrent que l'accroissement de la BACA permet de lever un frein à l'ingestion et de sécuriser les rations riches en énergie rapidement dégradable surtout lorsque l'apport en protéines est maintenu au plus juste.High producing dairy cows are commonly fed with highly digestible diets containing a high proportion of rapidly degradable starch. Obvious drawbacks to this strategy are the apparition of sub-acute rumen acidosis which lead to economic loses. The dietary cation-anion difference (DCAD) should aid in preventing acidosis since cations are absorbed in exchange of protons, whereas anions are absorbed in exchange of NaCO3-. The aim of this thesis was to 1) define DCAD recommendations and 2) describe the mechanisms implied. We made the hypothesis that responses were modulated by the proportion of rapidly degradable energy (4 or 22 % DM) (experiments 1, 2, 4). In experiment 3, DCAD were crossed with two proportions of proteins (90 and 115 PDIE/UFL). The DCAD were more important when diets provided high proportion of rapidly degradable energy and poor proportion of proteins, in agreement with our hypothesis. Effects appeared during the first week of the experiment and lasted during 12 weeks. Mechanisms implied may be précised. Nevertheless, the regulation of the acid-base stutus could partly explained the improvementof performance although a rumen effect could not be excluded. Renal excretion was the main way to excrete ions and urine PH seemed to be a good predictor of DCAD. Our results showed that increase DCAD could prevent the decrease in intake with diets rich in rapidly degradable energy and limiter in proteins.RENNES-Agrocampus-CRD (352382323) / SudocSudocFranceF

Microbiota succession during aerobic stability of maize silage inoculated with Lentilactobacillus buchneri NCIMB 40788 and Lentilactobacillus hilgardii CNCM‐I‐4785

Abstract Aerobic deterioration of silage following feeding out is responsible for the deterioration of its quality. Inoculation of silage with lactic acid bacteria is one strategy to limit these effects. A trial was performed using whole‐plant corn ensiled in bag silo, and forage was inoculated with Lentilactobacillus buchneri NCIMB 40788 (Lactobacillus buchneri) and Lentilactobacillus hilgardii CNCM‐I‐4785 (Lactobacillus hilgardii) or not (Control silage). After 159 days of fermentation, the silos were opened and the silage was sampled at 24‐h intervals during a 10‐day aerobic stability assay to measure pH, the fermentation profile, mycotoxins, and microbial and fungal populations. In inoculated silage, lactic acid concentrations and pH remained stable during the aerobic phase and higher microorganism alpha‐diversity was observed. Treated silage was characterized by a high abundance of Saccharomycetes and maintenance of Lactobacillus throughout the aerobic stability assay. The high aerobic stability of the inoculated silage contrasted with the decrease in lactic acid contents and the increase in pH observed in the Control silage, concomitantly with an increase in lactate‐assimilating yeast (Pichia and Issatchenkia), and in Acetobacter and Paenibacillus OTUs. Remarkably, Penicillium and roquefortine C were detected in this silage by day 8 following exposure to air. Our study highlighted the fact that the use of L. buchneri with L. hilgardii modified the consequences of exposure to air by maintaining higher microbial diversity, avoiding the dominance of a few bacteria, and preventing fungi from having a detrimental effect on silage quality

Fructo-oligosaccharides and glucose homeostasis: a systematic review and meta-analysis in animal models

Abstract The aim of this systematic review was to assess the effect of fructo-oligosaccharide supplementation on glucose homeostasis. The search process was based on the selection of publications listed in the Pubmed-Medline database until April 2016 to identify studies evaluating the impact of short-chain fructo-oligosaccharides or oligofructose on glucose homeostasis. Twenty-nine trials were included in the systematic review and the meta-analysis was performed on twelve of these papers according to the inclusion criteria. Fasting blood concentrations of glucose and insulin were selected as pertinent criteria of glucose homeostasis for the meta-analysis. The consumption of fructo-oligosaccharides decreased fasting blood glycaemia levels, whatever the metabolic status (healthy, obese or diabetic) and diet (low-fat or high-fat) throughout the experiment. This reduction was linear with prebiotic dose (from 0 to 13% of the feed). Fasting insulinaemia also decreased linearly with fructo-oligosaccharide supplementation but the reduction was only significant in rodents fed a low-fat diet. Potential underlying mechanisms include gut bacterial fermentation of fructo-oligosaccharides to short-chain fatty acids (SCFA) and bacterial modulation of bile acids, both interacting with host metabolism. This systemic review, followed by the meta-analysis, provides evidence that fructo-oligosaccharide supplementation has a significant effect on glucose homeostasis whatever the health status and diet consumed by animals

Gastro-Intestinal Microbiota in Equines and Its Role in Health and Disease: The Black Box Opens

International audienceHorses are large non-ruminant herbivores and rely on microbial fermentation for energy, with more than half of their maintenance energy requirement coming from microbial fermentation occurring in their enlarged caecum and colon. To achieve that, the gastro-intestinal tract (GIT) of horses harbors a broad range of various microorganisms, differing in each GIT segment, which are essential for efficient utilization of feed, especially to use nutrients that are not or little degraded by endogenous enzymes. In addition, like in other animal species, the GIT microbiota is in permanent interplay with the host's cells and is involved in a lot of functions among which inflammation, immune homeostasis, and energy metabolism. As for other animals and humans, the horse gut microbiome is sensitive to diet, especially consumption of starch, fiber, and fat. Age, breeds, stress during competitions, transportation, and exercise may also impact the microbiome. Because of its size and its complexity, the equine GIT microbiota is prone to perturbations caused by external or internal stressors that may result in digestive diseases like gastric ulcer, diarrhea, colic, or colitis, and that are thought to be linked with systemic diseases like laminitis, equine metabolic syndrome or obesity. Thus, in this review we aim at understanding the common core microbiome-in terms of structure and function-in each segment of the GIT, as well as identifying potential microbial biomarkers of health or disease which are crucial to anticipate putative perturbations, optimize global practices and develop adapted nutritional strategies and personalized nutrition

In vitro models of the canine digestive tract as an alternative to in vivo assays: Advances and current challenges

Dogs occupy a full place in the family, and their well-being is of paramount importance to their owners. Digestion, a complex process involving physicochemical, mechanical, and microbial parameters, plays a central role in maintaining canine health. As in vivo studies in dogs are increasingly restricted by ethical, regulatory, societal, and cost pressures, an alternative option is the use of in vitro models simulating the different compartments of the canine gastrointestinal tract. This review introduces digestion and gut microbiota as key factors in dog nutrition and health under both healthy and diseased conditions (obesity and inflammatory bowel disease) and highlights similarities and differences between the human and canine digestive tract and processes. We provide the first in-depth description of currently available models of the canine digestive tract, discuss technical and scientific challenges that need to be addressed, and introduce potential applications of in vitro gut models in the food and veterinary fields. Even if the development of some in vitro models is still limited by a lack of in vivo data in dogs that is necessary for relevant configuration and validation, translation of long-term expertise on human in vitro gut models to dogs opens avenues for model optimization and adaptation to specific canine digestive conditions associated with various dog ages, sizes, breeds and/or diets, in both physiological and diseased states

Composition and evolution of the gut microbiota of growing puppies is impacted by their birth weight

Abstract Low birth weight puppies present an increased risk of neonatal mortality, morbidity, and some long-term health issues. Yet it has not been investigated if those alterations could be linked to the gut microbiota composition and evolution. 57 puppies were weighed at birth and rectal swabs were performed at 5 time points from birth to 28 days of age. Puppies were grouped into three groups based on their birth weight: low birth weight (LBW), normal birth weight (NBW) and high birth weight (HBW). 16S rRNA gene sequencing was used to highlight differences in the fecal microbiota. During the first three weeks, the relative abundance of facultative anaerobic bacteria such as E. coli, C. perfringens and Tyzzerella was higher in LBW feces, but they catch back with the other groups afterwards. HBW puppies showed higher abundances of Faecalibacterium and Bacteroides during the neonatal period, suggesting an earlier maturation of their microbiota. The results of this study suggest that birth weight impact the initial establishment of the gut microbiota in puppies. Innovative strategies would be desired to deal with altered gut microbiota in low birth weight puppies aiming to improve their survival and long term health