Genetic statistical analysis of field data on fattening and carcass composition traits in meat sheep breeds from Schleswig-Holstein
Küçük Resim Yok
Tarih
2001
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Eugen Ulmer Gmbh Co
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
The production of lamb meat is of highest economic value in sheep production. For efficient production of slaughter lambs, the main breeding goals are high reproduction of ewes and high improvement of fattening and carcass composition performances. Objectives of this study were the development of a genetic statistical model for estimation of breeding values for fattening and carcass traits recorded on field-tested meat sheep from Schleswig-Holstein and the estimation of the genetic parameters of these traits. Data on meat sheep breeds of German white-headed meat sheep (GWHS), German black-headed meat sheep (GBHS), German Texel (GTS) and Suffolk were available. Traits analysed were live weight gain (LWG), body composition score (BC) and general type (GT) as well as ultrasonic measurements such as muscle depth (MD) and fat depth (FD). For all breeds an average LWG of 362 g/day was calculated and live weight gain of each breed was 371, 316, 354 and 364 g/day for GWHS, GBHS, GTS and Suffolk. respectively. Heritabilities of LWG for different breeds ranged between h(2) = 0.26 and 0.60. Body composition score showed heritabilities of moderate magnitude (h(2) = 0.23 to 0.39). Genetic correlations between BC and LWG ranged between r(g) = -0.08 and 0.57. Even lower heritabilities were obtained for general type (h(2) = 0.09 to 0.33). Genetic correlations of GT and LWG were of moderate magnitude with r(g) = 0.33 to 0.59. except of Suffolk. High genetic correlations were estimated between GT and BC (r(g) = 0.61 to 0.93). For GTS, heritabilities of muscle depth and fat depth were h(2) = 0.15 and 0.14, respectively. Corresponding estimates for Suffolk were h(2) = 0.20 and 0.21. respectively Genetic correlations between measured MD and visually scored BC were r(g) = 0.43 and 0.64 for GTS and Suffolk, respectively. Based on the results, it was concluded that lower variation of age at end of test would result in more reliable breeding values for fattening, exterior and carcass composition traits. Visually scored body composition should further be used as indirect trait for carcass composition in the genetic evaluation Ultrasonic measurements gave mon information about carcass composition relative to body composition score and should be included in the genetic evaluation, although their heritabilities were low. Therefore, improvement of the accuracy of ultrasonic measurements is necessary to obtain more informative traits for carcass composition of live animals.
Açıklama
Anahtar Kelimeler
Phenotypic Parameters, Lambs, Growth, Weight, Gain
Kaynak
Zuchtungskunde
WoS Q Değeri
Q4
Scopus Q Değeri
Cilt
73
Sayı
1
