Kamimura S, Nishiyama N, Ookutsu S, Goto K, Hamana K
Department of Theriogenology Kagoshima University, Kagoshima, Japan.
Theriogenology. 1997 Jun;47(8):1563-9. doi: 10.1016/s0093-691x(97)00161-1.
Fetal sex can be determined by the polymerase chain reaction (PCR) using cells from fetal fluid collected by transvaginal ultrasound-guided amniocentesis. A total of 35 aspirates from 30 cows, 15 Holsteins and 15 Japanese Blacks at 59 to 250 d of pregnancy were used. Five cows were aspirated twice at a 10-d interval. A 5.0 MHz convex array transducer connected to a scanner was inserted into the vagina under caudal epidural anesthesia. The transducer was equipped with a 65-cm long, 21-g needle within the probe carrier. A bovine male-specific primer and a bovine gender-neutral primer were used. Fetal fluid was obtained from all except 2 cows in early pregnancy. Five animals aborted within 1 wk following aspiration. A total of 33 samples, 29 of amniotic fluid and 4 of allantoic fluid, was subjected to PCR analysis. Fetal gender was verified in 31 33 samples (18 females and 13 males). Gender was also determined by gross examination of external genitalia of offspring after calving or abortion. Fetal gender was correctly identified by PCR analysis of aspirated fetal fluid in 16 16 females and in 13 15 males. Transvaginal ultrasound-guided amniocentesis followed by PCR analysis of aspirated cell DNA can be used accurately to determine fetal sex in cows at 70 to 100 d of gestation. The procedure requires considerable skill and is not without some risk to fetal viability.
可通过聚合酶链反应（PCR），利用经阴道超声引导羊膜穿刺术收集的羊水细胞来确定胎儿性别。本研究共使用了30头奶牛（15头荷斯坦奶牛和15头日本黑牛）在妊娠59至250天期间采集的35份羊水样本。5头奶牛每隔10天进行了两次样本采集。在尾椎硬膜外麻醉下，将连接扫描仪的5.0 MHz凸阵探头经阴道插入。探头内装有一根65厘米长、21G的穿刺针。使用了牛特异性雄性引物和牛性别中性引物。除2头妊娠早期奶牛外，其他奶牛均采集到了羊水样本。5头动物在采样后1周内流产。共33份样本（29份羊水样本和4份尿囊液样本）进行了PCR分析。33份样本中有31份（18头雌性和13头雄性）确定了胎儿性别。在犊牛出生或流产后，还通过肉眼检查后代的外生殖器来确定性别。通过对采集的羊水进行PCR分析，16头雌性和13头雄性中的15头胎儿性别得到了正确鉴定。经阴道超声引导羊膜穿刺术，随后对采集细胞的DNA进行PCR分析，可准确确定妊娠70至100天奶牛的胎儿性别。该操作需要相当高的技术，且对胎儿的生存能力存在一定风险。
