Ultrasonography was perfomed in 88 ewes from Núcleo de Pesquisas Zootécnicas Sudoeste - Instituto de Zootecnia, São Paulo state, from march to may , 2001. Animals were examined from 19º to 33º days of pregnancy by transrectal ultrasonography in alternate days examinations, and by pregnancy detector for small ruminants (DPPR-80Ò) from 25º to 45º day. Positive diagnostic by transretal ultrasonography was obtained after yolk sac visualization. The embryo heartbeat was observed after 25 day of pregnancy. The positive diagnostic was obtained by pregnancy detector when embrionic heart was 160 to 200 beats/minute. Births confirmed the examinations. Three abortions ocurred during the experiment and these females were excluded from the group. From 85 ewes examined, 64 lambed. The transrectal ultrasonography accuracy in 19º day of pregnancy was 35,29%, with higher rate (82,53%) in 31º day. The doppler accuracy in 25º day was 24,71% and 34,12.00% in 45º day. Embryo heartbeat was detected by transrectal ultrasonography after 21 days of pregnancy and the first placentoms were observed after 25 days of pregnancy. In conclusion, transrectal ultrasonography was better than doppler in early pregnancy diagnosis in sheep.
Ultrasound; Diagnosis; Ewes; Pregnancy
