In vitro evaluation of the effects of Yucca schidigera and inulin on the fermentation potential of the faecal microbiota of dogs fed diets with low or high protein concentrations

Acinetobacter in fresh faecal samples is related to sperm motility: A case report in Piétrain boars housed on different deep-litter bedding materials

The swine gastrointestinal tract contains a great variety of microbes, forming a complex and dynamic ecosystem. Various internal and external factors (e.g. age, breed and diet) may influence its composition. This study aimed to investigate the gut microbial diversity of German Piétrain boars housed on different deep-litter bedding materials (regional wood shavings, linen, hemp, spelt husks, and wood shavings) via 16S-rDNA sequencing. Additionally, short-chain fatty acids were analysed using gas chromatography. Fresh faecal samples (n = 80) from 40 Piétrain boars were collected twice during the trial. Although it can be assumed that boars ingest bedding orally, no differences in the microbiome composition could be found. The main phyla were Firmicutes and Bacteroides. Acinetobacter was identified as a biomarker for sperm quality differences (total sperm motility) in breeding boars.

Canine Mucosal Artificial Colon: development of a new colonic in vitro model adapted to dog sizes

Differences in dog breed sizes are an important determinant of variations in digestive physiology, mainly related to the large intestine. In vitro gut models are increasingly used as alternatives to animal experiments for technical, cost, societal, and regulatory reasons. Up to now, only one in vitro model of the canine colon incorporates the dynamics of different canine gut regions, yet no adaptations exist to reproduce size-related digestive parameters. To address this limitation, we developed a new model of the canine colon, the CANIne Mucosal ARtificial COLon (CANIM-ARCOL), simulating main physiochemical (pH, transit time, anaerobiosis), nutritional (ileal effluent composition), and microbial (lumen and mucus-associated microbiota) parameters of this ecosystem and adapted to three dog sizes (i.e., small under 10 kg, medium 10-30 kg, and large over 30 kg). To validate the new model regarding microbiota composition and activities, in vitro fermentations were performed in bioreactors inoculated with stools from 13 dogs (4 small, 5 medium, and 4 large). After a stabilization period, microbiota profiles clearly clustered depending on dog size. Bacteroidota and Firmicutes abundances were positively correlated with dog size both in vitro and in vivo, while opposite trends were observed for Actinobacteria and Proteobacteria. As observed in vivo, microbial activity also increased with dog size in vitro, as evidenced from gas production, short-chain fatty acids, ammonia, and bile acid dehydroxylation. In line with the 3R regulation, CANIM-ARCOL could be a relevant platform to assess bilateral interactions between food and pharma compounds and gut microbiota, capturing inter-individual or breed variabilities. KEY POINTS: • CANIM-ARCOL integrates main canine physicochemical and microbial colonic parameters • Gut microbiota associated to different dog sizes is accurately maintained in vitro • The model can help to move toward personalized approach considering dog body weight.

Comparison of the Effects of Yucca saponin, Yucca schidigera, and Quillaja saponaria on Growth Performance, Immunity, Antioxidant Capability, and Intestinal Flora in Broilers

The purpose of this study is to investigate the effects of Yucca saponin (YSa), Yucca schidigera (YS), and Quillaja Saponaria (QS) on growth performance, nitrogen metabolism, immune ability, antioxidant capability, and intestinal flora of yellow-feather broilers. This study randomly divided a total of 480 1-day yellow-feather broilers into 4 treatment groups. Factors in the 4 groups included CON group (basic diet), YSa group (basic diet mixed with 500 mg/kg YSa), YS group (basic diet mixed with 500 mg/kg YS), and QS group (basic diet mixed with 500 mg/kg QS). Throughout the 56-day study period, YSa, YS, and QS groups had higher average daily gain in broilers than the CON group (p < 0.01). The YS group had a lower feed gain ratio (F: G) in broilers than the CON group (p < 0.05). YSa, YS, and QS showed increased serum immunoglobin A (IgA), immunoglobin Y (IgY), immunoglobin M (IgM), and total antioxidant capacity (T-AOC) levels; enhanced acetic acid, butyric acid, and valeric acid levels of cecal content; and reduced contents of ammonia nitrogen, urea nitrogen, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and malondialdehyde (MDA) in serum in broilers (p < 0.05). The relative abundance of Lachnoclostridium in the QS group was decreased compared with that in the CON group (p < 0.05). Higher IgA and IgY sera contents were observed in the YS group compared to the YSa and QS groups (p < 0.05). In contrast with the QS group, the serum IL-6 concentration of the YS group was reduced (p < 0.05). In conclusion, YSa, YS, and QS promoted growth performance, nitrogen metabolism, immunity, antioxidant capability, and intestinal flora in broilers. Through the comparison of YSa, YS, and QS, it was found that YS is more suitable as a feed additive to ameliorate the healthy growth of broilers.

In vitro digestion and microbial fermentation of dried food residues, a potential “new” component for pet food, and different non-digestible carbohydrate sources

Food residues are often fed to dogs in private households and might also be a potential “new” ingredient for pet food in the future. As food residues might contain not only digestible, but also fermentable substrates, an effect on the intestinal microbiota can be assumed. In the present study, two batches of dried food residues (DFR) collected from hotels in Crete were microbially fermented in an in vitro batch culture system with canine fecal inoculum: non-sterile DFR including meat (DFRm), sterile DFR including meat (DFRms) and sterile DFR without meat (DFRwms). Different non-digestible carbohydrate sources (beet pulp, wheat bran, inulin, carrot pomace, brewer´s spent grains, cellulose and lignocellulose) were included for comparison. Inulin, cellulose and lignocellulose were only used as raw materials, while the other test substrates were incubated as raw and enzymatically pre-digested substrates. After incubation for 24 hours, the raw food residues markedly increased the concentrations of bacterial metabolites in the fermenters, although smaller effects were observed for the DFRwms. When the enzymatically pre-digested food residues were incubated, the effects were more pronounced for the DFRms and DFRwms. In general, when compared with the other test substrates, the food residues were microbially fermented to a comparable or partly higher extent. Interestingly, high n-butyrate concentrations were measured in the inocula, both after incubation of the raw and pre-digested food residues. In conclusion, the food residues contained enzymatically digestible and microbially fermentable substrates. If considered as a potential future ingredient for pet food, a standardization of the collection and processing of food residues might be necessary in order to reduce compositional variability and varying effects on the intestinal microbiota.

Yucca schidigera extract decreases nitrogen emission via improving nutrient utilisation and gut barrier function in weaned piglets

Yucca schidigera extract (YE) can decrease ammonia concentration in livestock housing, which could be associated with the inhibition of urease. The aim of this study was to investigate the other possible reasons of dietary YE supplementation reducing nitrogen emission in weaned piglets. A total of 14 crossbred weaned barrows were allotted into two groups fed the diets supplementing 0 and 120 mg/kg YE for 14 days. The YE administration decreased F/G ratio and hindgut NH₃ -N production in weaned piglets (p < 0.05). Dietary YE supplementation decreased serum urea nitrogen levels, and increased nutrient digestibility, which could be related to the improvement of morphology, digestive and absorptive enzyme activities, and nutrient transporter mRNA expression in jejunal mucosa of weaned piglets (p < 0.05). The mRNA expression of tight junction proteins, mucins and apoptosis-related genes was also improved by YE treatment in jejunal mucosa of weaned piglets (p < 0.05). In addition, dietary YE supplementation regulated the microbiota structure and volatile fatty acid content in distal intestine of weaned piglets (p < 0.05). These results suggest that YE administration can decrease hindgut NH₃ -N production in weaned piglets, which is associated with the increased nutrient utilization and gut-barrier function.