PSI-6 The Influence of a Single Administration of Prostaglandin on Estrus Synchronization in Range Sheep Production

Abstract Administration of a single injection prostaglandin after ram introduction has previously been reported as an effective method to synchronize estrus in ewes housed dry lot setting. The objective this study was investigate the effectiveness administered at beginning breeding season introduction, on synchronization range ewes. Western Whiteface cross ewes, which thirty-six were ½ blood South African Meat Merino (SAMM) and seventeen ¼ SAMM (total n=53) assigned one two treatments: control (CON; n=26) or (PG; n=27). Ewes utilized complete randomized block design stratified by percentage, body condition score (BCS) age. PG treatment 3 mL IM (Lutalyse, Zoetis Animal Health) approximately 60 h rams introduced with Rams (n=4) applied marking paint placed (d 0: December 21) remained for duration 56 d natural service. observed twice daily 0730 1700 0-10 16-21 season, experienced evaluator. At lambing, birth weight, sex, type recorded. MIXED GLIMMIX procedures SAS used analyze response, bred first 5 days lambing date, number lambs born, lamb weight. percentage included independent variable but found be nonsignificant removed from statistical model. proportion during not different among treatments (P ≥ 0.60). There no difference between CON date 0.82). = Treatment did influence 0.25). born per ewe tended influenced < 0.08), tending have more than Lamb weights 0.50). In conclusion, administration exposure expression, however, tend lambs.