Variations annuelles du comportement d'oestrus, du taux et des possibilités d'ovulations chez la brebis Peulh du Niger

Abstract

Summary. Annual

Seasonal variation in ovarian and oestrous activity of tropical Menz sheep as affected by plane of nutrition

“…However, although ewes in this study cycled yearround in accord with previous reports (Mittal and Ghosh, 1980) (Yenikoye, 1984) but this is the first time they have been associated with seasonality. The observation that ewes failing to cycle every month were as heavy as those that cycled, was interpreted as an indication that the nutrition and liveweight of the ewes as they approach the wet season and throughout this period, are not major potentiating factors for the depressed sexual behaviour observed.…”

“…Forty-eight pluriparous ewes of the Menz breed (Galal, 1983) were used, aged 3 to 5 yr, liveweight mean 22.9 ± 4.5 kg and condition score of 2.5 ± 0.6 (0 = emaciated and 5 = obese; Hossamo et al, 1986 (Yenikoye, 1984). Samples were taken every Friday by jugular venipuncture (10 ml) between 10.00 and 11.30 am.…”

Population de follicules ovariens chez la brebis Peul

“…Le troisième groupe (diamètre équivalent compris entre 0,45 mm et 5,8 mm) est surtout réduit par I'atrésie (taux d'atrésie = 40 p. lOO), mais aussi par le nombre de follicules quittant cette classe par ovulation, en moyenne tous les 17 jours chez la brebis Peul (11).…”