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Performance and rumen development of artificially reared calves to dietary butyrate supplementation
Recently, there has been increased interest in the potential of certain diet derived chemicals to enhance immune response, gastrointestinal health and growth potential of young livestock. Of those evaluated thus far, the short chain fatty acid butyrate has shown significant potential as an anti-pathogenic immune stimulant. The aim of this study was to determine the effect of sodium butyrate supplementation on calf performance, intestinal development and volatile fatty acids profiles in pre-weaned calves. Forty-four Holstein Fresian male calves with a mean age of 13 ± 5 days were divided into two equal groups and fed milk replacer supplemented with 4g of coated sodium butyrate (SB)/day or with no coated sodium butyrate (CON). Calves were allocated to a standard 56 day calf rearing requiem- Milk offered at 6 litre per day (125g/litre) for 10-49days and weaning over 7 days (49-56 days) by gradual reducing the allowance. Concentrate and water was offered to calves on an ad libitum basis thoughout the trial period. Milk replacer and concentrate intake was recorded daily using a computerised calf rearing system (Forster Technik, Germany). Bodyweight was measured weekly. Respiration rate, rectal temperature and faecal scores were recorded daily. At weaning (day 56) eight animals from each treatment (SB vs CON) were euthanized. Rumen digesta and tissue was harvested for volatile fatty acid (VFAs) and rumen development analysis. Calves supplemented with SB tended (P=0.08) to have higher pre-weaning growth rates compared to CON (0.69 versus 0.59 kg/day). At weaning SB calves (80.2 kg) were 3.2 kg heavier than the CON group (76.9 kg), with bodyweight difference detected from day 42 to weaning. Bodyweight differences between treatments were not evident prior to this (P>0.10). Total DMI was not different between dietary treatments, but pre-weaning SB supplementation tended (P=0.08) to improve feed conversion rate of the calves. There were no significant differences on rectal temperature, respiration rate and faecal score between the treatments. Rumen papillae length, width and perimeter were not affected by SB supplementation of milk replacer. Similarly, rumen concentrations of total VFAs were not altered by dietary treatments. In conclusion, the supplementation of milk replacer with coated sodium butyrate could improve pre-weaning performance of dairy calves.
Keywords: Butyrate, Dairy Calf, Rumen Development