Tropicultura (Jan 2006)
Stability Analyse for Yield and Yield Components of Selected Peanut Breeding Lines (Arachis hypogaea L.) in the North Province of Cameroon
Abstract
In order to determine if an adequate nutrition would allow the Sardi ewe lambs to mate during their first year of age, 32 ewe lambs (5-6 months of age) were divided into two groups of low (L) or high (H) nutrition plane. Each group received, in addition to a basal diet, 200 and 500 g head-1.day-1 respectively. Ewe lambs growth, onset of reproductive activity and postpuberty reproductive performances were recorded. During the trial, the H group showed a greater growth rate compared to the L group (74 vs 44 g per day). The H group attained normal cyclic ovarian activity earlier than the L group (322 vs 335 days) and a greater live weight (40 kg vs 35 kg). Furthermore, expression of first oestrus showed up 25 days sooner with ewe lambs 4 kg heavier in the H group as compared to the L group. While no ewe lambs in the L group lambed, following mating, 56% (9 out of 16) of the H group gave birth to a lamb at an average ranging from 16 to 17 months. The trial demonstrated that full reproductive activity attainment in Sardi ewe lambs is variable when considering both ovarian cycles initiation and oestrus expression. An adequate nutrition plane allows an earlier puberty and particularly enhances the fecundity at this time.
