A trial was conducted to determine the carry-over effect of supplementation in a previous year on the production of South African Mutton Merino ewes in the following year while grazing cereal stubble. Three hundred and sixteen ewes were divided into four flocks, of which two grazed oat stubble, and two grazed wheat stubble. Each of these four flocks was again subdivided into four groups, of which two subdivisions received supplementation and two received none. Four subdivisions received 200 g/d from the 6 March 1998 until the 28 May 1998, while the other four subdivisions received 200 g/d from the 5 March 1999 until the 18 April 1999. This was increased to 300 g/d from 19 April 1999 until the 25 May 1999. The ewes were weighed on a monthly basis. Due to supplementation in 1998, birth status (lambs born per ewes mated) showed a tendency to increase in 1999, while weaning status (lambs weaned per ewes mated) was not significantly affected by supplementation in the previous year. Both birth weight and weaning weight of lambs were negatively affected by supplementation in the previous year, possibly due to the tendency for the higher birth rate achieved. The initial live weight of the ewes as well as kilogram weaned lamb/ewe was unaffected by supplementary feeding in the previous year.
The carry-over effect of supplementation in the previous year on the production of South African Mutton Merino ewes
Author: L. Brundyn, T.S. Brand, A.V. Ferreira, B.B. Aucamp and A. Durand
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