Effect Of Undernutrition And Compensation On The Internal Environment And Bacterial Diversity Of Rumen In Lambs

This study investigated the effect of undernutrition (0～60d) and compensation(60～150d) on the internal environment and bacteria of rumen in lambs. Eighty lambs, with average body weight (14.72±1.10) kg, were divided into control group (CG), protein restricted group (PR), energy restricted group (ER) and Both protein and energy restricted group (BR). Dietary nutrition level were (ME10.88MJ/kg,CP15%),(ME10.88MJ/kg, CP10%),(ME9.41MJ/kg, CP15%) and (ME8.62MJ/kg,CP5.7%), during undernutrition period for CG, PR, ER and BR, respectively. However, in nutritional compensation phase all groups were offered the same levels diet (ME9.75MJ/kg, CP12%). The experimental results were showed as follow:(1) At the end of nutrition restriction and the nutrition compensation period, there were not significant changes in pH value NH3-N, BCP, VFA between the energy restricted group and control group; during nutrition restriction, the NH3-N of protein restricted group was significantly lower than that of CG (P<0.05) and acetic acid, propionic acid and total VFA significantly higher than those of CG(P<0.05), but they were lower than those of CG(P<0.05) at the end of the nutrition compensation stage. At the end of nutrition restriction, BCP of Both protein and energy restricted group were significantly lower than that of CG(P<0.05). The NH3-N, acetic acid, propionic acid and total VFA of Both protein and energy restricted group were significantly higher those that of CG (P<0.05). However, all of them were significantly lower than those of CG(P <0.05) at the end of the nutrition compensation period.(2) At the end of nutrition restriction period, a-amylase of Both protein and energy restricted group was significantly lower than that of CG(P<0.05), but cellulose activity was significantly higher than that of CG(P<0.05); at the end of the nutrition compensation stage, a-amylase and neutral protease of both protein and energy restricted group were significantly higher than that of CG(P<0.05) but cellulose activity was significantly lower than that of CG(P<0.05).(3) At the end of nutrition restriction stage, the sample similarity of the same group was greater than80%, the profiles of CG and ER are gathered for a bunch, the similarity was more than70%. At the same time, PR and BR are gathered for a bunch; at the end of Compensation stage, different groups cluster had across each other, the similarity of all groups increased to64%. (4) Under this daily ration restricted, protein restricted group and both protein and energy restricted group had significant effect on the internal environment and bacteria of rumen in lambs.