Effect Of Complete Diet Pellets With Different Combinations On Fattening

Sixty crossbred lambs of Dorset Down( ) X Tibetan sheep( )(thirty intact male lambs and thirty wether lambs) were divided into five groups. Each group was fed with one diet. Groups 1 to 4 were designed as three factors of 2 X 2 X 2 factorial designing .Group 5 was fed with N-HMM-Ca instead of the same ratio of cottonseed cake based on group 1 to find the effect of N-H1ThI-Ca?nutrition on lambs. The results indicated : (1) All the tested groups performanced well in production. Daily weight gain were 0.238, 0.256, 0.266, 0.245, 0.247kg1d in order of group, close or exceede to the recommended value of NRC(O.2SOkgId). (2)Effects of A factor .. B factor and their cross effects on the intake, daily weight gain and feed conversion of lambs had no significant difference(P>O.05). (3) Factor A factor B and their cross effects had no significant influence (P>0.05) on the metabolic rate of energy or nitrogen retention of lambs. (4) A factor and B factor had no significant effect (P>0.05) on the pH value of rumen liquid in most sampling times. One hour after lambs intake, the pH of rumen liquid showed weak acid, 5 hours latter it was weak alkaline, all this indicated the fiture of diets in which concentrate was dominant position and the reasonable of feeding principle every four hours. (5) Factor A and factor B had significant effect (P<0.05) on NH3-N concentration of rumen liquid in certain sampling times. Contrast with peak results of NH3-N concentration after 1-?.5 hours from some experiments, this experiment showed: the NH3-N concentration of each group descended 1 hour latter of intake , the N113-N concentration came back to the level before intake 8 hours latter. (6) Between four diets there were no significant difference (P>0.05) to the performance of slaughter, but A2(sugarseet pulp) factor had better effect to lamb carcass than A1(wheat) factor. (7) The intake , daily gain and feed conversion of intact lambs is very significant higher (P<0.01) than wether lambs, but the metabolic rate of energy and nitrogen retention between them had not significant difference (P>0.05), this result indicated that maybe the intake was the main reason of the intact lambs daily gain higher than wether lambs. (8) The production performance and the metabolic rate of energy and nitrogen retention between group 1 and 5 had no significant difference(P>0.05), but the ability of fat deposition of group 5 was the higher than group 1.