Authors : A. Mohamed , S. Khaldi , B. Rekik and G. Khaldi
Abstract: Seventy five Sicilo-Sarde dairy ewes were divided into 3 equally sized groups homogeneous for litter size, 18 and 7 ewes with single and twin lambs, respectively. A weaning mode was applied for each group: lambs weaned at 45 days of age (GI), lambs gradually weaned between 45 and 90 days of age and fully separated from ewes at 90 days of age (GII) and lambs weaned at 90 days of age (GIII). During the suckling period, milk production was estimated by the hormonal method (5 IU of oxytocin). During the milking period, normal and residual milk were determined by hand milking followed by the injection of 2.5 IU of oxytocin. Milk production during the suckling period was not affected by litter size (p>0.05). It was estimated at 64.6, 81.1 and 109.2 kg for ewes with single lambs 59.7, 77.2 and 111.9 kg for ewes with twins in GI, GII and GIII, respectively. Compared to the 90 day weaning, early and progressive weaning have resulted in higher commercialised milk yield from both single (65.7 and 72.6 kg vs. 46.6 kg) and twin (75.2 and 67.6 kg vs. 48.6 kg) suckling ewes. The effect of litter size on collected milk was important (p<0.05) only in the case of early weaning. The weaning mode of lambs had also affected (p<0.01) the residual milk which was 24.5, 28.5 and 18.2 kg for GI, GII and GIII, respectively. This residual quantity of milk depended (p<0.05) on the number of suckled lambs during only the first 6 milking weeks. Milk production of Sicilo-Sarde ewes may be improved by applying early or progressive weaning regimes.
A. Mohamed , S. Khaldi , B. Rekik and G. Khaldi , 2008. Normal and Residual Milk Yields in Sicilo-Sarde Ewes: Effects of Litter Size and the Weaning Age of Lambs. Research Journal of Animal Sciences, 2: 144-148.