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Abstract : |
The present study was conducted to determine eye muscle (m. longissimus lumborum) properties of Kivircik lambs at weaning. The depth, width and area of eye muscle and the thickness of fat covering this muscle at the cross sectional area between the 12 and 13th ribs was determined using ultrasonic measurements from 90 lambs taken from three different flocks. At this time, the weaning weights of lambs was also recorded. The overall mean weaning weight of lambs was 26.8 kg at 125 days. Weaning weight was found to be significantly affected by flock, sex and birth type of lambs except dam age. Lamb age as a covariate on weaning weight was not a significant effect. Least-squares means for ultrasonic measurement of depth, width and area of eye muscle and backfat thickness were 19.67أƒâ€ڑأ‚آ±0.35 mm, 48.1أƒâ€ڑأ‚آ±0.61 mm, 6.91أƒâ€ڑأ‚آ±0.157 cm2 and 1.2أƒâ€ڑأ‚آ±0.08 mm, respectively. The variation observed between flocks means were higly significant for eye muscle width and area, significant for backfat thickness, but not significant for muscle depth. The lamb sex was found only to be a significant variable for muscle depth. Age of dam and the birth type of lamb were not significant sources of variation for the ultrasonic measurements. All phenotypic correlations within ultrasonic criteria and weaning weights of lambs, were significant and correlation coefficients ranged between 0.36 and 0.85. Lambs are marketed at weaning or a short time thereafter by the majority of breeders in Western Anatolia, such as breeders in Aydin province. It is extremely difficult to take measurements on carcasses in these regions as lambs are mainly marketed or slaughtered as small groups or individually and abattoirs do not record any measurements on carcasses characteristics. In this situation, information on body composition of lambs can be obtained practically by ultrasonic measurements on live animals. When combined in a breeding program with lamb weaning or market weights, these measurements will provide a way to increase both meat yield and the quality of Kivircik lambs., |
