Litter size and piglet traits of gilts with different prolactin receptor genotypes
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- 作者：van Rens ; Birgitte T.T.M. ; van der Lende ; Tette
- 关键词：Pigs ; Prolactin receptor gene ; Litter size ; Teat number ; Puberty ; Placenta
- 刊名：Theriogenology
- 出版年：2002
- 出版时间：January 15, 2002
- 年：2002
- 卷：57
- 期：2
- 页码：883-893
- 全文大小：110 K
文摘
Seventy-seven Large White×Meishan F2 crossbred gilts with prolactin receptor (PRLR) genotype AA (n=26), AB (n=36) and BB (n=15) were compared for teat number (FTm), age at first estrus, gestation length (GL), litter size, and litter means of functional teat number (FTp), birthweight (BW), and pre-weaning growth rate (GR). Own placental information was available for 88 % of 620 live-born piglets (62 gilts), since placentae were labeled during farrowing. The effect of PRLR genotype of the mother on average placenta weight (PLW) and placenta efficiency (EFF=BW/PLW), was therefore, also analyzed. PRLR genotype significantly (P<0.05) affected age at first estrus and, as a result (since the gilts were inseminated at a fixed estrus number), age and bodyweight at insemination. Furthermore, PRLR genotype affected total number of piglets born (TNB, P=0.056) and number of piglets born alive (NBA, P=0.072), but it did not affect (P>0.3) GL, BW or GR, neither before nor after correction for litter size. BB gilts were significantly younger at first estrus and younger and lighter at insemination than AA gilts (P<0.05). AA gilts had larger TNB (P=0.047) and tended to have a larger NBA (P=0.062) than BB gilts. TNB was 11.4±0.7, 10.8±0.6, and 8.8±0.9; NBA was 11.1±0.6, 10.5±0.6, and 8.7±0.9; BW was 1309±40, 1277±34, and 1290±53g; and GL was 113.6±0.3, 113.8±0.3, and 113.5±0.4 days for AA, AB and BB gilts, respectively. The effects on litter size and age at first estrus are independent effects. PRLR affected PLW (P=0.050) and EFF (P=0.066), resulting in a difference between AA and BB gilts. PLW was 160±9, 181±7 and 196±11g and EFF was 7.6±0.2, 7.3±0.2 and 6.7±0.3 for AA (n=19), AB (n=29) and BB (n=14) gilts, respectively. After correction for TNB, the differences disappeared. Functional teat number of the AA, AB and BB gilts was 15.35±0.22, 15.53±0.18, and 15.60±0.29, respectively, and was not affected by PRLR genotype (P=0.7). Functional teat number of piglets from AA, AB and BB mothers was 14.20±0.10, 14.37±0.08, and 14.63±0.13, respectively. Piglets from BB mothers had on average larger numbers of functional teats compared to piglets from AA mothers (P=0.028). In conclusion, PRLR gene is a major gene or marker for age at first estrus, litter size, and litter average of number of functional teats in the Large White×Meishan F2 crossbred gilts studied. The favorable allele for litter size (A allele) is the unfavorable allele for age at first estrus and for litter mean of functional teat number.