Andres C J, Green M L, Clapper J A, Cline T R, Diekman M A
Purdue University, West Lafayette, IN 47907.
J Anim Sci. 1991 Sep;69(9):3754-61. doi: 10.2527/1991.6993754x.
To determine whether recombinant porcine somatotropin (rpST) alters reproduction, 40 crossbred gilts weighing 59.1 +/- .5 kg at 125 +/- 1 d of age were assigned randomly to an experiment arranged as a 2 x 2 factorial. Eight gilts were given daily injections of diluent until they reached 104 kg BW (DW), and eight received diluent injections until puberty (DP). Twelve gilts were given rpST (4 mg/d) until 104 kg BW (PW) and 12 were given rpST injections until puberty (PP). All gilts were individually fed on an ad libitum basis an 18% CP corn-soybean meal diet (1.2% lysine and 3.1 Mcal/kg of ME). Beginning at 5 mo of age, gilts were exposed 20 min daily to mature boars. Serum concentrations of progesterone were measured weekly from 5 to 8 mo of age to verify age of puberty. Gilts observed in pubertal estrus were mated to two different boars 10 h apart. At 47 +/- 1 d of gestation, gilts were slaughtered to assess fetal development. After 60 d of treatment, serum LH and FSH profiles were determined in blood samples drawn at 20-min intervals for 4 h from eight diluent- and eight rpST-treated gilts fitted with indwelling jugular catheters. By 28 d, feed intake, feed/gain, and blood urea nitrogen were decreased (P less than .005) by rpST. Treatments did not affect (P greater than .05) the proportion of gilts attaining first ovulation (DW = 6/6; DP = 10/10; PW = 7/9; PP = 14/14) or conception rate (DW = 5/6; DP = 7/10; PW = 4/6; PP = 11/12).(ABSTRACT TRUNCATED AT 250 WORDS)
为了确定重组猪生长激素（rpST）是否会影响繁殖性能，将40头125±1日龄、体重59.1±0.5千克的杂交后备母猪随机分配到一个按2×2析因设计的试验中。8头后备母猪每日注射稀释剂直至体重达到104千克（DW组），8头则注射稀释剂直至发情（DP组）。12头后备母猪每日注射rpST（4毫克/天）直至体重达到104千克（PW组），12头则注射rpST直至发情（PP组）。所有后备母猪均自由采食含18%粗蛋白的玉米-豆粕型日粮（赖氨酸含量1.2%，代谢能3.1兆卡/千克）。从5月龄开始，后备母猪每天与成年公猪接触20分钟。从5至8月龄每周测定血清孕酮浓度以确定发情年龄。观察到处于发情期的后备母猪与两头不同的公猪间隔10小时交配。在妊娠47±1天时，屠宰后备母猪以评估胎儿发育情况。处理60天后，从8头安装了颈静脉留置导管、分别接受稀释剂和rpST处理的后备母猪采集血样，每隔20分钟采集一次，共采集4小时，以测定血清促黄体生成素（LH）和促卵泡生成素（FSH）水平。到28天时，rpST使采食量、料重比和血尿素氮降低（P＜0.005）。各处理对后备母猪首次排卵比例（DW组6/6；DP组10/10；PW组7/9；PP组14/14）或受孕率（DW组5/6；DP组7/10；PW组4/6；PP组11/12）无显著影响（P＞0.05）。（摘要截短于250词）
