Effect of dietary restriction and subsequent re-alimentation on the transcriptional profile of bovine ruminal epithelium

peer-reviewedCompensatory growth (CG) is utilised worldwide in beef production systems as a management approach to reduce feed costs. However the underlying biology regulating the expression of CG remains to be fully elucidated. The objective of this study was to examine the effect of dietary restriction and subsequent re-alimentation induced CG on the global gene expression profile of ruminal epithelial papillae. Holstein Friesian bulls (n = 60) were assigned to one of two groups: restricted feed allowance (RES; n = 30) for 125 days (Period 1) followed by ad libitum access to feed for 55 days (Period 2) or (ii) ad libitum access to feed throughout (ADLIB; n = 30). At the end of each period, 15 animals from each treatment were slaughtered and rumen papillae harvested. mRNA was isolated from all papillae samples collected. cDNA libraries were then prepared and sequenced. Resultant reads were subsequently analysed bioinformatically and differentially expressed genes (DEGs) are defined as having a Benjamini-Hochberg P value of <0.05. During re-alimentation in Period 2, RES animals displayed CG, growing at 1.8 times the rate of their ADLIB contemporary animals in Period 2 (P < 0.001). At the end of Period 1, 64 DEGs were identified between RES and ADLIB, with only one DEG identified at the end of Period 2. When analysed within RES treatment (RES, Period 2 v Period 1), 411 DEGs were evident. Genes identified as differentially expressed in response to both dietary restriction and subsequent CG included those involved in processes such as cellular interactions and transport, protein folding and gene expression, as well as immune response. This study provides an insight into the molecular mechanisms underlying the expression of CG in rumen papillae of cattle; however the results suggest that the role of the ruminal epithelium in supporting overall animal CG may have declined by day 55 of re-alimentation.SMW received financial assistance from Science Foundation Ireland (SFI) contract no 09/ RFP/GEN2447

Influence of sugar beet pulp on feeding behavior, growth performance, carcass quality and gut health of fattening pigs

Description of the subject. Dietary fiber is largely used in pig production but some contradictions appear in the literature regarding the effects on performance and health. Objectives. This paper aims to contribute to the clarification of the effects of a diet rich in sugar beet pulp on animal behavior, growth performance, carcass quality and gut health of fattening pigs. Method. Two successive batches of 24 fattening pigs were each divided into two groups fed ad libitum either a standard diet based on cereals (STD, 19% NSP [non-starch-polysaccharides]) or a fibrous diet based on 23% sugar beet pulp (HFD, 31% NSP). Results. Pigs activity rate and feeder occupancy duration were increased by 57% and 165% for group fed HFD, respectively (P < 0.05). The fecal bacteria counts showed increases with HFD for Lactobacillus (10.21 vs 9.84 log10 of cfu·g-1 of feces dry matter, P < 0.05) and Bifidobacterium (9.49 vs 8.88, P < 0.01) but decreases for Enterobacteriaceae (4.85 vs 5.97, P < 0.001). Reductions of the average daily gain (788 vs 876 g per day, P < 0.001) and the dressing percentage (75.7 vs 78.9%, P < 0.001) were observed with HFD. Gastric lesion score was decreased with HFD (0.82 vs 1.55, P < 0.05). For pigs fed HFD, the proportion of surface area occupied by goblet cells was increased in the jejunum (10.06 vs 7.99%, P < 0.01) and the number of CD3 lymphocytes was increased in the colon (1.24 vs 0.90·mm-², P < 0.05). Conclusions. HFD contributes to strengthen the gut health of fattening pigs, but it impairs growth performance and carcass traits