Some yield characteristics of ivesi, ost-friz x ivesi (F1) crossbreed lambs

84 7. SUMMARY This study was undertaken to investigate the growth, survival ability, fattening, carcass characteristics and body size of the Ivesi, Ost-Friz x Ivesi (Fi) crosssbred lambs. The data were obtained from 23 Ivesi, 23 Ost-Friz x Ivesi (Fi) crossbred lambs in suckling period, and also from 7 Ivesi, 9 Ost-Friz x Ivesi (Fi) crossbred ram lamb in fattening period in this study. The data regarding carcass characteristics were obtained from 7 Ivesi, 6 Ost -Friz x Ivesi (Fi) crossbred ram lambs. The effects of genotype, sex, type of parturition and mother age on the weight of the lambs at parturition and the day 15, 30, 45, 60, 75, 90 and 105 were analysed by the Least Squares Method, and test was utilised to compare the body size between the groups. The average birth wieght was 4.15 and 4.65 kg, the weaning weight (105th day of age) 15.39 and 18.31 kg, the daily live weight gain from birth to the weaning was 105.86 and 128.43 g and the survival ability at weaning was 82.61% and 86.96% in the Ivesi and Ost - Friz x Ivesi (Fi) crossbred lambs, respectively. The lambs were chosen at the weight of 20 kg and fattened until they reached 45 kg. During this period, daily live weight gain was 225.22 and 222.68 g in the Ivesi and Ost-Friz x Ivesi (Fi) crossbred lambs, respectively. At the same period, consumption of concentrated fed and alfalfa hay for 1 kg body weight gain was 5.98 and 3.73; 5.15 and 3.33 kg, respectively. All lambs were slaughtered at the weight of 45 kg, and the characteristics of the carcass were examined. Cold carcass weight (21.80 and 20.93), carcass dressing percentage (48.31% and 44.79), percentage tail fat (11.60% and 1.72%), percentage loin (31.04% and 30.79%), body length at one year of age (63.40 and 73.90 cm), thorax (chest) depth (98.20 and 104.20 cm), rump region (60.10 and 66.50 cm), eye muscle (ELD) area (19.08 and 16.08 cm2) and backfat thickness (19.08 and 16.08 cm2, P<0.001) were recorded in the Ivesi and Ost-Friz x Ivesi (Fi) crossbred lambs, respectively.