SHORT SYNCHRONIZATION PROTOCOL: LAMBING RATE AFTER AI IN SARDA EWES Falchi L.1, Meloni G.2, Mara L.1, Gallus M.1, Dattena M.1 1AGRIS-Sardegna (DIRPA), 07040, Olmedo, Italy, 2Dipartimento di Medicina Veterinaria, Università degli studi di Sassari, Italy INTRODUCTION Nowadays, the only protocol used for oestrus synchronization used in AI campaigns in Sarda ewes is the conventional one of 14 days. Shortening the time of exposure to progesterone might have beneficial effects on the management of an AI program and on animal welfare, reducing the incidence of vaginal infections. The aim of the study was to test the efficiency of a 7 day protocol of synchronization on lambing rates in Sarda ewes during the breeding season. 180 Sarda ewes n=90 “CONVENTIONAL PROTOCOL” “SHORT PROTOCOL” 14 days of intravaginal sponges of Medroxyprogesterone acetate (60mg) + PMSG (400IU) at sponge removal Cloprostenol (125μg) 7 days of intravaginal sponges of AI at 55 hours after sponge removal (400x106spz/straw) Pregnancy rates (42 days after AI) Lambing rates (145±5 days after AI) MATERIALS AND METHODS RESULTS There was no difference in pregnancy rates between the conventional 14 days synchronization protocol and the short 7 days one (45.5% vs 43.3%; P>0.05) Data were confirmed at 145±5 days (see graph below) Shortening the time of exposure to progestagen providing luteolysis at the moment of sponge insertion does not affect pregnancy rates in ewes during the breeding season and could be effectively used as a valid alternative in AI programs. Moreover this protocol might reduce the incidence of vaginitis overcoming the concerns about animal welfare. TAKE HOME MESSAGE