Hunter M G, Faillace L S, Picton H M
Department of Physiology and Environmental Science, Faculty of Agricultural and Food Sciences, University of Nottingham, Leicestershire, UK.
Reprod Fertil Dev. 1994;6(6):783-9. doi: 10.1071/rd9940783.
Six Meishan and five Large White hybrid gilts were naturally mated to boars of the same breed during their tenth or third oestrous cycle respectively. Maternal serum progesterone and total oestrone were monitored throughout the pregnancy period. On Day 30 of gestation, all gilts were slaughtered and ovulation rate, embryonic survival, conceptus development and intrauterine steroidogenesis were evaluated. The results of the study confirm previous reports that Meishan pigs have a higher number of live conceptuses (P < 0.03), a higher rate of embryonic survival (92.1% v. 78.6% for Large White hybrids) and a higher ovulation rate (P < 0.02) than Large White hybrid gilts. Embryos from Large White hybrid gilts were heavier (P < 0.001) than Meishan embryos and placental lengths (P < 0.001) and weights (P < 0.001) were greater. The volume of allantoic fluid per conceptus was greater (P < 0.03) in Large White hybrid gilts. The oestradiol concentration in the allantoic fluid was greater in Large White hybrid gilts (P < 0.002), but the progesterone concentration in allantoic fluid did not differ (P > 0.15) between the breeds. More oestradiol was synthesized in vitro on a wet weight basis from placental tissue in Large White hybrid gilts than in Meishan gilts (P < 0.001); however, a positive linear relationship existed in both breeds between oestradiol synthesis and placental length (P < 0.005). Progesterone concentrations in maternal serum tended to be higher overall (P < 0.1) in Meishan gilts than in Large White hybrid gilts throughout the 30-day period of study and were significantly higher (P < 0.02) from Day 13 to Day 30.(ABSTRACT TRUNCATED AT 250 WORDS)
分别在梅山母猪的第10个发情周期和大白杂交母猪的第3个发情周期，将6头梅山母猪和5头大白杂交母猪与同一品种的公猪自然交配。在整个妊娠期监测母血清孕酮和总雌酮水平。在妊娠第30天，屠宰所有母猪，评估排卵率、胚胎存活率、孕体发育和子宫内类固醇生成。研究结果证实了先前的报道，即梅山猪比大白杂交母猪有更多的存活孕体（P<0.03）、更高的胚胎存活率（大白杂交猪为78.6%，梅山猪为92.1%）和更高的排卵率（P<0.02）。大白杂交母猪的胚胎比梅山猪的胚胎重（P<0.001），胎盘长度（P<0.001）和重量（P<0.001）更大。大白杂交母猪每个孕体的尿囊液体积更大（P<0.03）。大白杂交母猪尿囊液中的雌二醇浓度更高（P<0.002），但不同品种间尿囊液中的孕酮浓度无差异（P>0.15）。以湿重计，大白杂交母猪胎盘组织体外合成的雌二醇比梅山母猪多（P<0.001）；然而，两个品种中雌二醇合成与胎盘长度之间均存在正线性关系（P<0.005）。在整个30天的研究期内，梅山母猪母血清中的孕酮浓度总体上倾向于高于大白杂交母猪（P<0.1），并且在第13天至第30天显著更高（P<0.02）。（摘要截短于250字）
