| One hundred and twenty Lamb after same method fattening were used in this study and deviled into 12 groups according to the crossbreeding times and the age group, (F1, F2, F3 and age 6, 8and 10 age In month) were measured traits of body. Four of each group was selected to measure some items as follows slaughter and carcass traits, physical and chemical traits of muscle and histological properties muscle fiber. The disparity in each trait was studied using variance analysis some detail analyses were made for the relations of each trait, Got 11 traits about the Lamb through cluster analysis. Evaluation about the comprehensive traits of the Lamb used principal component analysis and Predicted models to Lamb yield were established by regression analysis. Which could provide same reference for multi-objective selection of the traits of carcass and meat quality in Boer Goat crossbreeding GuanZhong Goat. The results were follows: 1.Traits of carcass and meat quality at the various groups had significant differences (p<0.05 P<0.01) in hybridization and Guanzhong Goat. there are many difference in traits of carcass:①Withers height, body length, chest girth, the depth of chest and paunch had significant differences (p<0.05 P<0.01) in hybridization and Guanzhong Goat. ②Significant differences in weight were including the average live weight, carcass weight, meat weight and Average Daily Gaining. The hybridization superior to AuanZhong Goats, F1 at 6 month Average Daily Gaining 216g/d; The dressing percentage, net percentages of carcass, the meat percentage of carcass were significant differences between the hybridization and AuanZhong Goats. The differences of the meat-bone ratio of the bisket and rib, the breech and hindquarter were very significant. The hybridization have good carcass for lamb. The dressing percentage F2 at 8 month 44.54%. 2. The meat quality in hybridization and Guanzhong Goat had significant differences:①the chemical analysis of muscles shown that the content of crude protein, crude fat, special (amino acid)were significant difference to control groups. Especially, the IMF various and content about the fatty acid. Short chain fatty acids and satiric (18.0) was lower. Lanoline acid (18.2) and Oleic acid were higher than control groups. The contents about cholesterol in mussel were lower in hybridization than AuanZhong Goats, and were significant differences (p<0.05); ②Eating quality was significant differences between the hybridization and Guanzhong Goat. Hybridization of meat color, tenderness, undesirable flavor are superior to control groups, and was significant differences (P<0.05). 3.Traits of carcass and meat quality at the various age of hybridization was significant differences:①The dressing percentage of GuanZhong goat and hybridization lamb became higher with growth of age. There was significant differences between 8 month and 10 month (P<0.05), In addition, there were not significant differences at 3 age groups (P>0.05) in dressing percentage, net meat percentage and meat-bone ratio, and the F2 at 10 month was the best of the groups (40.54%, 79.8%and 4.84). It was good time to slaughter at 10 month depended on the effective economical, the live weight, carcass weight, net meat weight, born weight, chest girth, GR value, ribeye area increased significantly with age (p<0.05);②meat color was not difference at various age (P>0.05), fat deposition appeared after 8 month age became higher with growth of age, flavor and undesirable flavor are significant differences than before. Tenderness at 6 ages in month was the best of the groups;③The chemical analysis of muscles shown that the content of crude protein, crud fat, oleic acid and unsaturated fatty acid Increased significantly with age(p<0.05),but the content of water and crude ash in muscle was not significant differences at 3 age groups(p>0.05).In addition the diameter of muscle fiber increased significantly with age (P<0.05). 4. Phenotype correlation analysis shown, that the traits of carcass and meat quality had very close relationship. ①There were close relationship in differences hybridization about the traits of carcass and meat quality. There were significant relationship between live weight and other traits, Including chest girth, age, carcass, length of body, lag girth, rib eye area and GR value meat weight, carcass length,born meat ratio, marbling crude fat,the content of crude protein and special amino acid and histological traits of muscle fiber (p<0.05,P<0.01),which suggested that live weight has influence on the Properties of carcass and meat quality. ②The significant relationship between shear force and diameter of muscle fiber shown that the more small diameter of muscle fiber were, the more tender meat were and the density of muscle fiber & the mount of muscle fiber Indicated that the meat became older with decrease of them. Furthermore, IMF and GR value had significantly relationship (r = 0.76629,P<0.01). 5. The traits of carcass and meat quality were classified respectively into eleven major characteristic groups which could reflect rather comprehensively the Properties of carcass and meat quality on the lever of threshold T=0.58 and T=4.78 by using cluster analysis. The typical traits were selected to make Principal component analysis from major characteristic groups obtained by cluster and about 88.27% total variance information was synthesized through the former 4 Principal component which could Provide same reference for multi-objective selection of the traits of carcass and meat quality In Lamb. 6. It was important that carcass were cut into different Portion of meat whose percentage were used to evaluate Lamb Performance in the product of high quality lamb. The studies shown that Lamb Performance can be reflected by the retail cuts Percentage Which had significant relationship with carcass weight, meat weight, dressing Percentage net meat Percentage (P<0.05 or P<0.01) seven Items, live weight, age, carcass, length of body, chest girth, lag girth, rib eye area and GR value were selected to predict the Percentage of different retail cuts weight to carcass weight. On the basis of this study, three equations were obtained as follows: the dressing Percentage of lamb=3.9288+1.7175×age +0.26820×chest girth +0.856708×lag girth,the meat Percentage of lamb=8.45201+0.29320×length of body+5.94820×GR value,the Percentage of superior quality lamb= 29.2066+0.66783×lag girth+0.43808×rib eye area, at the same time to be the reference for establish stander of Lamb.
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