Effects of supplementation of the stabilized rumen extract to Tuj lambs diets on fattening performance, rumen fermentations and diet digestibility.

摘要

This study was carried out to determine the effects of addition of the stabilized rumen extract (SRE) to early weaned lamb diets on fattening performance, rumen fermentations and diet digestibility. As model, two months old male tuj lambs (n=18) were divided into three groups, each containing 6 animals. The study was conducted for 56 days, followed by an adaptation period of 10 days. The groups were fed a basal diet consisting of 20% hay and 80% concentrate, ad libitum. Diets of the experimental groups were supplemented with 0 (control group), 1 (group 1), and 2 (group 2) g of SRE/day/lamb. Body weights of the control group, group 1, and group 2 were 13.90, 13.85, 13.80 kg (P=0.999), respectively, at the beginning of the study, and were 23.07, 25.47 and 25.48 kg (P=0.567) at the end of the study. The average daily body weight gains of the groups were 163.93, 207.40, and 208.63 g/d (P<0.05). Hence, the average total feed consumptions were 895.29, 1168.39 and 1069.35 g, and the feed conversion ratios were 5.42, 5.72 and 5.16 (P=0.717) for the control group, group 1 and group 2, respectively. Levels of the dry matter (DM), organic matter (OM) and crude protein (CP) digestibility were not different statistically among the groups. No significant difference was detected also among the groups in terms of the rumen pH and NH₃-N scores. Although acetic acid, propionic acid and butyric acid scores were not statistically different among the groups, those of the total volatile fatty acid, valeric acid and isovaleric acid were significantly lower in the treatment groups.