Application Of B-Mode Ultrasound Diagnostic Technology In Reproduction Of Female Donkey

With the development of scaled donkey industry in China,the reproductive techniques of large-scale donkey farms are facing some new challenges.Compared to the traditional rectal palpation method,the use of ultrasonographic examination can identify estrus and predict ovulation more accurately,can make early pregnancy diagnosis earlier and more accurate.There is few report of systematic research for diagnosing female donkey reproductive diseases by ultrasound technique.The purpose of this study is by use ultrasonographic techniques to establish a B-mode ultrasound imagination and to obtain some valuable reference data,to explore the application of ultrasound diagnostic technology of estrus detection,ovulation prediction,early pregnancy diagnosis and reproductive disease diagnosis in female donkey,so that ultrasound diagnostic technology may be more widely used in donkey reproductive management.Healthy China Dezhou female donkeys were selected in breeding season,follicle development statuses were detected by use transrectal ultrasonography.It has showed that the growth rate of the dominant follicles was 3.45±0.88mm/d from 5d to Id prior to ovulation,the follicle diameter was 37.3±4.1mm around 1 day prior to ovulation.At about 24h before ovulation the shape of preovulatory follicles were changed from circular to oval;several hours prior to ovulation,the follicular walls were thickened and the follicular edges of were changed irregular,the follicle shape was changed to pear-shaped(or teardrop-shaped),and the stigma moved to the ovulation fossa;The ovulation interval of the female donkey during the breeding season was 23.05± 2.57 days;the foal-heats of the postpartum female donkeys were occurred between 5 and 13 days in general,and there were no obvious estrous signs in some postpartum female donkey.The first postpartum ovulations were 5.0%in donkeys of 9?10 days after foaling,11?15d accounts for 78.13%,16?17d accounts for 13.75%,and 18?19d accounts for 3.12%.After breeding the female donkey were ultrasonographic examined for early pregnancy diagnosis by the postovulatory 15?18days,it was showed that the growth rate of embryo vesicles were about 3.1±0.7mm/d in diameter.The earliest time to find embryo vesicle was d11 postovulation,the conceptus lost its circular shape at d19,about d23 the embryo proper can be seen,fetal heartbeat can be detected at about d25,and the amnion can be seen at d29.There was no significant difference of pregnancy rate between the inseminations of uterine horn and uterine body.The pregnancy rate of foal heat breeding donkey is higher than that of previous nonpregnant donkey.In this study,some ovarian diseases were diagnosed by evaluation the size,structure and echo intensity of ovaries and follicles.Ultrasound was used for diagnosis of mucometra,pyometra and endometritis.Researches show that:1.Ultrasound examination can be used for estrus detection and follicle development more accurately,especially for ovulation prediction.2.Application of ultrasound examination can detect embryo vesicle earlier,and can evaluate embryo and fetal development more accurately.3.By use of ultrasound examination,the diagnosis of ovarian and uterine diseases become more easy and more intuitive.