| Popis: |
Reproductive inefficiency is one of the most important and cost limiting factor to profitable small ruminant production in the tropics. The aim of this study was to evaluate the influence of breed on oestrus response, reproductive and oestradiol 17 β profiles in Red Sokoto (RS), Sahelian (SH) and West African Dwarf (WAD) goats following synchronisation with prostaglandin F2α (PGF2α). Thirty (N = 30) apparently healthy; RS (n = 10), SH (n = 10) and WAD (n=10) goats, aged between 1.5 – 2.0 years, and body condition score of 3.0 – 4.0 were used for the study. Each doe was synchronised with 1 mL (0.26 mg) cloprostenol sodium (Synchromate®) given as a single intra-muscular injection on Day 0. Prior to synchronisation, a 5mL blood sample was collected from each doe on Day 0, (pre- synchronisation sample) and subsequently on Day 1, Day 2 and Day 3 post-synchronisation for determination of serum reproductive and oestradiol17β profiles. The findings of the study were as follows: Oestrus response rates (%): RS; 100.0; SH; 100.0; WAD; 0.0; pregnancy rate (%): RS; 70.0; SH; 20.0; WAD; 0.0. The Sahelians that kidded (SHK) had significantly higher (P < 0.05) serum progesterone concentration than Sahelian that did not kid (SHN); Red Sokoto goats that kidded (RSK) had significantly higher (P< 0.05) serum concentrations of oestradiol-17β than Red Sokoto that did not kid (RSN); oestradiol-17β was higher in RSK than SHN (P < 0.05). It is, therefore, concluded that: Red Sokoto goats responded better to PGF2α-based oestrus synchronisation than Sahelian and WAD. Oestradiol-17β activity was comparatively higher in RS than in SH and WAD between Day 1 and Day 3 post-synchronisation with PGF2α. WAD goats were completely non-responsive to oestrus synchronisation with PGF2α. It is therefore recommended that WAD goat will require more time (approximately 6 months) to adapt to the Northern Guinea Zone for their hypothalamo-pituitary- Ovarian axis to be activated sufficiently to cycle, ovulate and develop functional corpus luteum that will respond to PGF2α. |
