Effects of Birth Type, Genotype and Nutritional Management on Growth Performance of Female Lambs
Keywords:
crossbred, feeding strategies, single, Tsigai, twin.Abstract
The present study evaluated the growth dynamics of female lambs of the Tsigai breed (rusty variety) and triracial crossbreds (50% Suffolk × 37.5% German Blackface × 12.5% Tsigai) from birth to 8.5 months under controlled management conditions. A total of 124 female lambs were allocated into four groups according to breed and birth type: twin Tsigai (L1, n = 18), single Tsigai (L2, n = 62), twin crossbred (L3, n = 11), and single crossbred (L4, n = 33). Body weights were recorded at birth, at weaning, at 7 months, and at 8.5 months, and both total weight gain and average daily gain (ADG) were calculated.
During the first two periods (pre-weaning and post-weaning up to 7 months), all lambs were fed identical rations. In the final period (7–8.5 months), the twin Tsigai females received a modified concentrate diet containing yeast. Twin Tsigai females exhibited the lowest ADG during both the pre-weaning (187.51 g/day) and post-weaning periods (92.97 g/day), but the highest ADG in the final period (153.44 g/day).
These findings highlight the importance of implementing targeted nutritional strategies for lambs with lower initial growth potential, particularly in order to improve performance during later developmental stages.
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