Authors : R.W. Godfrey , A.J. Weis and R.E. Dodson
Abstract: St. Croix White hair sheep ewes were used to evaluate the effect of supplemental nutrition prior to breeding during the dry and wet seasons on St. Croix. Beginning 21 d prior to breeding ewes were fed supplement in addition to grazing guineagrass pasture (FEED). Other ewes in the flock grazed pasture only (CONTROL). This study was conducted during the dry (June and July) and wet seasons (October and November). Data were analyzed by SAS using treatment and season as main effects. Days to estrus was greater (P < 0.01) in the dry than in the wet season (11.2 " 1.3 vs 6.5 " 1.3 d, respectively) but there was no difference (P > 0.10) in days to conception (11.6 " 1.4 vs 9.2 " 1.4 d, respectively). There was no effect (P > 0.10) of treatment or season on ovulation rate. Progesterone after estrus was higher (P < 0.0001) during the wet than the dry season (14.3 " 0.4 vs 11.1 " 0.4 ng/mL, respectively). The FEED ewes in the wet season gave birth to more lambs (P < 0.03) than FEED ewes in the dry season (2.2 " 0.2 vs 1.6 " 0.2 lambs, respectively) but there was no effect of season on the CONTROL ewes. Flushing of hair sheep ewes under tropical conditions does not appear to enhance ovulation rate during either the dry or wet seasons. The increase in the number of lambs born to ewes flushed during the wet season may be due to the natural occurrence of higher ovulations rates in ewes at that time of the year on St. Croix.
R.W. Godfrey , A.J. Weis and R.E. Dodson , 2003. Effect of Flushing Hair Sheep Ewes During the Dry and Wet Seasons in the U.S. Virgin Islands. Journal of Animal and Veterinary Advances, 2: 184-190.