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The objective of these studies was to evaluate the seasonal maintenance of body weight (BW) and condition, signs of fescue toxicosis, and reproductive performance of straightbred and cross-bred hair sheep grazing tall fescue or bermudagrass forage. Breeds examined were St. Croix (SC), Romanov (ROM) and cross-bred ewes. BW was measured in the summer (1998–2000) and the fall (1999) on ewes grazing bermudagrass overseeded with ryegrass (BER) or tall fescue (FES) forage. Body condition score (BCS) and serum prolactin concentrations were determined in the summer (1999, 2000) and fall (1999). Pregnancy and lambing rates of a summer and fall (1999) breeding season and pregnancy rates of the spring (2000) breeding season were recorded. BW and BCS reflected seasonal differences related to the forage availability of BER and FES, seasonal variations in toxins of FES forage and breed differences. At all times, serum prolactin concentrations were reduced in ewes grazing FES pastures (P |
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