Dietary supplementation with 0.8% L-Arginine between days 0 and 25 of gestation reduces litter size in gilt
X Li, FW Bazer, GA Johnson, RC Burghardt, DW Erikson, JW Frank, TE Spencer, I Shinzato, and G Wu, 2010. Journal of Nutrition, 140: 1111–1116.
09-Aug-2010 (15 years 9 months 29 days ago)The present study was conducted to test the hypothesis that dietary supplementation with L-arginine during the first 25 d of pregnancy would ameliorate embryonic loss in pigs. The results obtained results indicated that supplementation with 0.8% L-arginine between d 0 and 25 of gestation reduced the number of corpora lutea (CL), concentrations of progesterone in maternal blood and the conceptus, as well as litter size. These unexpected findings are novel and important, because they question the long-standing view that augmenting total daily feed intake of gilts (e.g. from 2 to 4 kg/d and, therefore, doubling arginine intake) reduces embryonic/fetal survival due to increased intake of dietary energy.
In this study, it was determined the effects of L-arginine supplementation during early pregnancy on embryonic/fetal survival and growth in gilts. Gilts were housed individually in pens and fed twice daily 1 kg of a corn- and soybean meal-based diet supplemented with 0.0, 0.4, or 0.8% L-arginine (wt:wt) between d 0 and 25 of gestation (10 gilts/treatment). The diets were made isonitrogenous by addition of appropriate amounts of L-alanine. At d 25 of gestation, gilts were fed L-alanine or L-arginine and hysterectomized 30 min later to obtain uteri and conceptuses (embryos and associated fetal membranes and fluids). Dietary supplementation with 0.4 or 0.8% L-arginine enhanced (P<0.05) its concentrations in maternal plasma (64 and 98%, respectively) as well as the vascularity of chorionic and allantoic membranes, compared with the control group. Reproductive performance [numbers of corpora lutea (CL) and fetuses, placental and fetal weights, and embryonic mortality] did not differ between the 0.4% Arg and control groups. However, supplementation with 0.8% L-arginine decreased (P<0.05) uterine weight (-20%), total number of fetuses (-24%), CL number (-17%), total fetal weight (-34%), total volume of allantoic and amniotic fluids (-34 to 42%), concentrations of progesterone in maternal plasma (-33%), as well as total amounts of progesterone (-35%), estrone (-40%), and estrone sulfate (-37%) in allantoic fluid, compared with the control group.
These results indicate that dietary supplementation with 0.8% L-arginine between d 0 and 25 of gestation, while increasing placental vascularity, adversely affects the reproductive performance of gilts.
In this study, it was determined the effects of L-arginine supplementation during early pregnancy on embryonic/fetal survival and growth in gilts. Gilts were housed individually in pens and fed twice daily 1 kg of a corn- and soybean meal-based diet supplemented with 0.0, 0.4, or 0.8% L-arginine (wt:wt) between d 0 and 25 of gestation (10 gilts/treatment). The diets were made isonitrogenous by addition of appropriate amounts of L-alanine. At d 25 of gestation, gilts were fed L-alanine or L-arginine and hysterectomized 30 min later to obtain uteri and conceptuses (embryos and associated fetal membranes and fluids). Dietary supplementation with 0.4 or 0.8% L-arginine enhanced (P<0.05) its concentrations in maternal plasma (64 and 98%, respectively) as well as the vascularity of chorionic and allantoic membranes, compared with the control group. Reproductive performance [numbers of corpora lutea (CL) and fetuses, placental and fetal weights, and embryonic mortality] did not differ between the 0.4% Arg and control groups. However, supplementation with 0.8% L-arginine decreased (P<0.05) uterine weight (-20%), total number of fetuses (-24%), CL number (-17%), total fetal weight (-34%), total volume of allantoic and amniotic fluids (-34 to 42%), concentrations of progesterone in maternal plasma (-33%), as well as total amounts of progesterone (-35%), estrone (-40%), and estrone sulfate (-37%) in allantoic fluid, compared with the control group.
These results indicate that dietary supplementation with 0.8% L-arginine between d 0 and 25 of gestation, while increasing placental vascularity, adversely affects the reproductive performance of gilts.