Genetic and phenotypic parameters of ultrasonic and needle soft tissue depth measurement in live lamb and their correlation with carcass fat in Lori-Bakhtiari lambs

In this study in order to estimate the phenotypic and genetic parameters of the ultrasonic and needle measurement of soft tissue depth in live lambs and their relationship with carcass fat five years data of Lori-Bakhtiari lambs were used. Soft tissue depth over the 12th rib at 12cm from the dorsal midline (GR) in 1482 Lori-Bakhtiari lambs at the age of six months using an animal model of scanner device 480، also with needle No. 22 in the desired area was determined. Of these about 247 lambs were slaughtered at the age of six months. The means for ultrasonic and needle soft tissue depth measured in live lambs (UGR and NGR) with soft tissue depth in carcass (CGR) were 8. 44، 7. 69 and 8. 62، respectively. The estimates of heritability and standard error for UGR، CGR، subcutaneous fat and total carcass fat traits were 0. 23 ± 0. 05، 0. 29 ± 0. 14، 0. 28 ± 0. 011 and 0. 30 ± 0. 10، respectively. Due to the high phenotypic correlation between the UGR and NGR with CGR and subcutaneous fat (0. 64، 0. 68 and 0. 65، 0. 73، respectively) also the moderate to high genetic correlations between them of these (0. 55، 0. 94 and 0. 77، 0. 92، respectively) techniques can be used for selection programs. It is possible to replace the needle soft tissue depth measureing instad of ultrasound soft tissue depth due to phenotypic and genetic correlations with CGR and carcass traits.