Study Of Lean-Percentage Prediction On Pig Carcasses And The Establishing Of Carcass Grading System In China

In order to establish one or several models on prediction lean-percentage as soon as possible on the slaughtering line, finally the price policy that much content lean with a little fat carcass will be pay much money and little content lean with much fat will be pay a little money is coming true. Lean-percentage prediction on pig carcasses and the establishing of carcass grading system in China were studied in this paper. This paper was made up of three parts. Firstly, compared of the effect of different animal types on the prediction equations for pig carcass classification. Then, the data obtained from carcass experiments of measurement and cutting was analyzed by SAS8.2 and SPSS11.0. Three equations on prediction lean-percentage for pig carcass off skin and several indexes for carcass classification were chosen. Based on the three models the author assumed three modes about pig carcass grading standard, trying to complement the blank of China.The first part: 389 pigs (92 local breeds, 111 local crossbreed, 114 ab extra crossbreed and 72 leanest-bred) were studied to predict carcass lean-percentage, compare the correlation coefficients among characteristics and the effect of different animal types on prediction equations of lean-percentage. The results showed: 1) The lean meat content of local-breed pigs, local-crossbreed pigs, ab-extra-crossbreed pigs and leanest-bred pigs was gradually improved. While the backfat thickness of carcasses was gradually reduced. There was a intensity negative (P<0.0001) between the lean meat content and backfat thickness. 2) There existed diversities of the prediction equations on lean-percentage among different animal types. Pig breeds or crossbreed types affected the prediction equation on carcass lean-percentage of swine.In order to estimate the carcass classification of hogs on the slaughtering line regardless of judging the animal types of swine. The second part: 325 hog carcasses were random chosen on slaughtering line. The indexes of lean meat content, hot carcass weight and backfat thickness et al were measured, and the lean meat content as y others indexes as...