tailieunhanh - Báo cáo sinh học: "Effects of divergent selection for leg weakness on muscle and bone characteristics in Duroc swine*

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: Effects of divergent selection for leg weakness on muscle and bone characteristics in Duroc swine* | 363 Genet Sei Evol 1992 24 363-374 Elsevier INRA Original article Effects of divergent selection for leg weakness on muscle and bone characteristics in Duroc swine DD Draper1 MF Rothschild2 LL Christian2 1 Department of Veterinary Anatomy Iowa state University Ames 50011 I A 2 Department of Animal Science Iowa state University Ames IA 50011 USA Received 9 January 1992 accepted 4 May 1992 Summary - The dimensions and weights of front leg muscles tendons and bones were determined in 44 gilts that were offspring of three Duroc lines from a five-generation divergent-selection experiment on leg weakness. Lines were low control and high with the low line having the greatest leg weakness and the high-line having the least leg weakness. At a slaughter weight of approximately 118 kg the right front leg was removed from the carcasses of 14 low- 16 control- and 14 high-line gilts. Each intrinsic muscle was dissected from origin to insertion removed from the leg and measured for total length and weight. The skeleton of the front leg was disarticulated so that each bone was freed and thoroughly cleaned of muscle remnants and connective tissue. The shoulder and elbow joints were scored for the presence of osteochondral lesions. Each bone was weighed and various dimensional traits were measured. The model used to analyze the data included the effects of line sire within line and weight as a covariate. The biceps brachii muscle weight and length were significantly greater in low-line pigs than in control- or high-line pigs p . Collectively the forearm extensor weights were significantly greater in low-line pigs than in control- or high-line pigs P . The humeral and metacarpal bones were shorter in high-line pigs than in control- or low-line pigs P . The head of the humerus was wider and the angle of the head of the humerus was greater in high-line pigs than in control- or low-line pigs P . Divergent selection for differing degrees of leg soundness in Duroc .