Supplementation on summer veld for the finishing of old ewes.
Six groups of old Dohne merino-type ewes in poor condition were used in a trial at the ARI, Potchefstroom and were allotted to one of the following treatments: (i) Slaughtered at commencement of the trial; (ii) Fed ad lib. in kraal with a pelleted diet consisting of 60% lucerne hay and 40% yellow maize meal; (iii) Veld grazing + whole yellow maize with the aim of achieving the same growth rate as that of Group 2; (iv) Veld grazing + 454 g whole maize/sheep/day; (v) Veld grazing + 227 g whole maize/sheep/day; (vi) Control, veld grazing alone. The trial was repeated for three years and commenced each year with the first mass gains during early summer. Trial animals, except for Group 1, were fed until 30% mass gain had been achieved and were then slaughtered. Depending on the state of the veld, the quantity of maize supplemented and the feeding period of Group 3 differed considerably between years. Average daily gains (ADG) of Group 2 (211,0 g/sheep/day) were highly significantly (P ≤0,01) higher while those of Group 6 (72,6 g) were highly significantly (P ≤0,01) lower than those of other treatments (134,7 g; 132,0 g and 111,0 g for Groups 3, 4 and 5, respectively). Average daily gains of Groups 3 and 4 were also significantly (P ≤0,05) higher than those of Group 5. Groups with the highest growth rates also had the highest dressing percentages. This investigation showed that energy supplementation of summer veld for the finishing of old ewes had a definite advantage when compared with a system of immediate marketing or when no supplementation was given.