Weaning-associated feed deprivation stress causes microbiota disruptions in a novel mucin-containing in vitro model of the piglet colon (MPigut-IVM)

Background Risk factors for the etiology of post-weaning diarrhea, a major problem in swine industry associated with enormous economic losses, remain to be fully elucidated. In concordance with the ethical concerns raised by animal experiments, we developed a new in vitro model of the weaning piglet colon (MPigut-IVM) including a mucin bead compartment to reproduce the mucus surface from the gut to which gut microbes can adhere. Results Our results indicated that the MPigut-IVM is able to establish a representative piglet archaeal and bacterial colon microbiota in terms of taxonomic composition and function. The MPigut-IVM was consequently used to investigate the potential effects of feed deprivation, a common consequence of weaning in piglets, on the microbiota. The lack of nutrients in the MPigut-IVM led to an increased abundance of Prevotellaceae and Escherichia-Shigella and a decrease in Bacteroidiaceae and confirms previous in vivo findings. On top of a strong increase in redox potential, the feed deprivation stress induced modifications of microbial metabolite production such as a decrease in acetate and an increase in proportional valerate, isovalerate and isobutyrate production. Conclusions The MPigut-IVM is able to simulate luminal and mucosal piglet microbiota and represent an innovative tool for comparative studies to investigate the impact of weaning stressors on piglet microbiota. Besides, weaning-associated feed deprivation in piglets provokes disruptions of MPigut-IVM microbiota composition and functionality and could be implicated in the onset of post-weaning dysbiosis in piglets.

Effect of Partial Feed Deprivation on Serum Liver Enzymes’ Activities and Hepatic Histoarchitecture in Clarias gariepinus (African Catfish)

The aim of this study was to evaluate serum liver enzymes’ activities and hepatic histoarchitecture in partially feed-deprived Clarias gariepinus (African Catfish). A total of forty-eight (48) active, live and apparently normal catfish randomly placed into two groups were used for this study. Fish in control group (labeled B) were fed with 4% of their body weight twice daily while fish in the feed-deprived group (labeled A) were fed with 25% of that quantity fed to the control group. Blood and liver samples were obtained at intervals of 7 days for 28 days for alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP), and for histopathology respectively. Results revealed significantly higher (P < 0.05) values for ALT, AST and ALP in the feed-deprived group (A) compared to the control group (B). On histopathology, liver sections of feed-deprived fish showed lipid vacuolation and this became accentuated over the period and most prominent on day 28. The study has demonstrated that starvation in catfish produced liver damage reflected by increase in serum activities of these liver enzymes.

Systems-wide effects of short-term feed deprivation in obese mice

While prolonged fasting induces significant metabolic changes in humans and mice, less is known about systems-wide metabolic changes in response to short-term feed deprivation, which is used in experimental animal studies prior to metabolic challenge tests. We here performed a systems biology-based investigation of connections between gut bacterial composition and function, inflammatory and metabolic parameters in the intestine, liver, visceral adipose tissue, blood and urine in high-fat fed, obese mice that were feed deprived up to 12 h. The systems-wide analysis revealed that feed deprivation linked to enhanced intestinal butyric acid production and expression of the gene encoding the pro-thermogenic uncoupling protein UCP1 in visceral adipose tissue of obese mice. Ucp1 expression was also positively associated with Il33 expression in ileum, colon and adipose tissue as well as with the abundance of colonic Porphyromonadaceae, the latter also correlating to cecal butyric acid levels. Collectively, the data highlighted presence of a multi-tiered system of inter-tissue communication involving intestinal, immune and metabolic functions which is affected by feed deprivation in obese mice, thus pointing to careful use of short-feed deprivation in metabolic studies using obese mice.

Response of domestic chickens to fasting and non-fast moulting programmes in a humid tropical environment

The study evaluates the effect of fasting and non-fasting (Zn supplementation) moulting methods on performance of indigenous (IC) and Shaver brown (SB) hens in the hot humid tropical environment of Nsukka, Southeastern Nigeria. One hundred and twenty indigenous and Shaver brown hens (60/genotype) aged between 75 and 80 weeks were shared into three groups (20/group), T : hens fed layers diet at 125 g/bird/day (control group), T : hens fed 1 2layers mash supplemented with 20,000ppm Zn as ZnO at 125 g/bird/day for 14 days, and T : 3 hens subjected to feed deprivation (FD) for 14 days. Water was given ad libitum to all birds. Data analyzed were pre-moult and moulting body weight, hen day egg production (HDEP), and egg weight. Moulting method significantly (p<0.05) affected body weight in SB but not in indigenous hens; hen day egg production and day to stoppage of egg production in bothgenotypes with FD resulting in greater loss in body weight and an early cessation of egg production compared to zinc supplementation. Shaver Brown hens subjected to ZnO and FD lost 15.6 and 26.7 % of their initial body weight, respectively while IC lost 16.2 and 32.6 %, respectively. Hen day egg production was 0.00 ± 0.00 % in the last week of moulting in SB and IC moulted by FD but 8.32 ± 6.47 % for SB and 10.71 ± 3.25 % for IC moulted by ZnO. Egg production stopped on day 10 (D10) and 6 in SB hens submitted to ZnO and FD, respectively and on D13 and 5, respectively for the IC. In conclusion, zinc supplementation at 20,000ppm in the diet of laying chickens as moulting agent is a milder but equally effective moulting method as fasting and is recommended for intensive commercial and rural indigenous poultry production.

Systems-wide Effects of Short-term Feed Deprivation in Obese Mice

While prolonged fasting induces significant metabolic changes in humans and mice, less is known about systems-wide metabolic changes in response to short-term feed deprivation, which is used in experimental animal studies prior to metabolic challenge tests, and hence, information on the effects of varying length of feed deprivation is warranted. We here performed a systems biology-based investigation of connections between gut bacterial composition and function, inflammatory and metabolic parameters in the intestine, liver, visceral adipose tissue, blood and urine in obese mice that were feed deprived for varying durations up to 12 hours. The systems-wide analysis revealed that increased duration of feed deprivation linked to enhanced intestinal butyric acid production and expression of the gene encoding the pro-thermogenic uncoupling protein UCP1 in visceral adipose tissue of obese mice. Ucp1 expression was also positively associated with Il33 expression in ileum, colon and adipose tissue as well as with the abundance of colonic Porphyromonadaceae, the latter also correlating to cecal butyric acid levels. Collectively, the data highlighted presence of a three-tiered system of inter-tissue communication involving intestinal, immune and metabolic functions which is affected by the duration of feed deprivation in obese mice, thus pointing to careful use of short-feed deprivation in metabolic studies using mice.