Productivity of Timahdite and D'man x Timahdite ewes lambing in the autumn, spring and summer in Morocco

The reproductive performance of 1117 Timahdite and D'man x Timahdite ( D x T) ewes lambing in the autumn, spring and summer, and weights and survival to 90 days of their 968 lambs were evaluated. All ewes were exposed to Meat Lacaune rams. The lambing rate of Timahdite ewes was 42% lower than that of D x T ewes. The litter size at birth and at 90 days of D x T ewes was 0.23 and 0.19 lamb, respectively greater than those of Timahdite ewes. D x T crossbred ewes weaned 4.1 kg weight more than Timahdite ewes. The lambing rate, litter size at 90 days and litter weight at birth and at 90 days of summer- lambing ewes were 43%, 0.39 lamb, 0.23 kg and 17.7 kg, respectively lower than those of autumn-lambing ewes. They were also 25%, 0.49 lamb, 1.3 kg and 14.6 kg, respectively lower than those of spring- lambing ewes. The dam's genetic group had significant effects on lamb birth weight, but not on weight at 30 days and 90 days and survival. Spring- born lambs had the highest birth weight and survival, and autumn- born lambs had the highest weight at 30 days and 90 days. It was concluded that D x T crossbred ewes had better productivity than Timahdite ewes at any lambing season. Furthermore, flocks that rely on pasture for their nutrition should avoid summer lambing, which results in low ewe and lamb performance.