摘要
Background: Two studies were conducted to evaluate the effects of dietary natural betaine on sow reproductive performance during summer(Exp. 1) and non-summer months(Exp. 2). Treatments were designed as a 2 × 2 factorial arrangement with factors including dietary betaine(0 or 0.2%) and period of supplementation(lactation or post-weaning until 35 days post-insemination). In Exp. 1, 322 and 327 sows and in Exp. 2, 300 and 327 sows representing young(parity 1 and 2) and mature(parity 3 to 6) sows, respectively, were used.Results: In Exp. 1, supplementation of betaine during lactation increased sow body weight losses(-11.95 vs.-14.63 kg;P = 0.024), reduced feed intake(4.12 vs. 4.28 kg/d;P = 0.052), and tended to reduce percentage of no-value pigs(P = 0.071). Betaine fed post-weaning reduced weaning-to-estrus interval(5.75 vs. 6.68 days;P = 0.054) and farrowing rate(86.74% vs. 91.36%;P = 0.060), regardless of parity group. Post-hoc analysis with sows clustered into 3 parity groups(1, 2 and 3, and 4+) indicated that betaine fed in lactation to parity 4+ sows(P = 0.026) and betaine fed post-weaning to parity 1 sows increased the number of pigs born in the subsequent cycle(P ≤ 0.05). In Exp. 2, betaine fed during lactation tended to reduce the weaning-to-estrus interval(6.64 vs. 7.50 days;P = 0.077) and farrowing rate(88.23% vs.83.54%;P = 0.089), regardless of parity group. Feeding betaine post-weaning reduced number of pigs born(13.00 vs.13.64;P = 0.04) and pigs born alive(12.30 vs. 12.82;P = 0.075), regardless of parity group.Conclusions: Using 0.2% betaine during the non-summer months did not benefit sow performance. During the summer, betaine supplementation in lactation increased subsequent litter size in parity 4+ sows. Betaine fed during the post-weaning period reduced the wean-to-estrus interval and farrowing rate, increased total number of pigs born for parity 1 sows and reduced total number of pigs born to parity 4+ sows. Further research is needed to determine if the detrimental effects on feed intake and farrowing rate may be correlated and depend on dietary betaine level.
基金
National Pork Board (Des Moines, IA
NPB Project#13–052)。