The Effects Of Dietery Fiber Levels On Reproductive Performance Of Sows During Pregnancy

The present study was conducted to investigate the effects of three dietary fiber levels in the gestation diet on the reproductive performance, plasma metabolic hormone and piglets organ development of sows during their first two parities. Three hundred ninty-nine cross-bred (LandracexYorkshine) gilts, with similar age and body condition, were randomly allocated to three diets including 10.8%NDF (Low fiber group,LF; n=132), 15.8%NDF (Medium fiber group,MF; n=132),20.8%NDF (High fiber group,HF; n=135) during 0-90 days of gestation. Sows during last pregnancy(from d 91 to farrowing) and lactation period(from farrowing to d 24 of lactation) were fed the same diets across groups respectively. During the experiment period, all sows obtained the same nutrients intake daily except the fiber by adjusting feed intake among three groups. Blood samples were collected on 13 d,54 d,85 d and 109 d in parity 1 and on 25 d,54 d,85 d in parity 2 for measuring Estradiol and Leptin concentration. In parity 2,15 newborn piglets from farrowing sows in each group were killed before suckling colostrum for organ index calculation (liver,heart,kidney,stomach,intestine and lung). The results indicated that:1,The effect of dietary fiber levels on reproductive performance of primiparous sows was distinct. The No.of total born piglets were increased significantly by 0.74 (P<0.05) and 1.05 (P<0.01) respectively in low-fiber group than medium-fiber group and high-fiber group; The No.of born alive pigltes were also increased significantly by 1.01 in low-fiber group than high-fiber group(P<0.01); The weight of piglets born alive were decreased significantly by 0.05 kg in low-fiber group than medium-fiber group(P<0.05), but the piglets wt. on lactation 22 d and litter wt. on lactation 22 d were increased significantly by 0.36 kg (P<0.05) and 3.31 kg(P<0.05) respectively in low-fiber group than high-fiber group; The backfat thickness after farowing 20 d were decreased significantly in low-fiber group than high-fiber group; No effects of dietary fiber levels on feed intake in lactation, WEI, days of pregnancy, duration of farrowing and born litter wt. were observed(P>0.05).2,The effect of dietary fiber levels on reproductive performance of sows on parity-2 was distinct. The No.of total born piglets were increased significantly by 0.91(P<0.05) and 1.03 (P<0.05) respectively in medium-fiber group than low-fiber group and high-fiber group; The No.of born alive pigltes were also increased significantly by 0.92(P<0.05) and 0.95 (P<0.01) respectively in medium-fiber group than low-fiber group and high-fiber group; The piglets wt. at birth were increased significantly by 1.86 kg (P<0.01) in medium-fiber group than low-fiber group; There were no differences on the born piglets weight, litter weight at lactation 22 d, piglets weight at lactation 22 d (P>0.05); No effects of dietary fiber levels on feed intake in lactation, WEI, days of pregnancy were observed(P>0.05).3,The plasma Estradiol and Leptin concentration of gestation sows were affected by different fiber levels.The level of Estradiol were decreased significantly in high-fiber group than low-fiber group on pregnancy 13 d of parity-1(P<0.05); The level of Estradiol were decreased significantly in high-fiber group and medium-fiber group than low-fiber group on pregnancy 25 d of parity-2(P<0.05); The level of Estradiol were decreased significantly in high-fiber group than low-fiber group on pregnancy 54 d of parity-2(P<0.05); The level of Estradiol were decreased significantly in high-fiber group than medium-fiber group on pregnancy 85 d of parity-2(P<0.05).The level of Leptin were decreased significantly in high-fiber group than low-fiber group on pregnancy 25 d of parity-2(P<0.05); The level of Leptin were decreased significantly in low-fiber group than high-fiber group on pregnancy 54 d of parity-2(P<0.05).4,The viscera indexes in newborn piglets of parity-2 sows were affected by different fiber levels. Liver indexes were higher significantly in high-fiber group than medium-fiber group(P<0.01) and low-fiber group(P<0.05); Heart indexes were higher significantly in high-fiber group than low-fiber group (P<0.05); Kidney indexes were higher significantly in high-fiber group than medium-fiber group(P<0.05) and low-fiber group(P<0.05).The conclusion: 1,The reproductive performance of sows during their first two parities were affected significantly by dietary fiber levels. Daily intake of 222 g NDF is favor to reproductive performance on primiparous sows, daily intake of 365 g NDF is more suitable for parity-2 sows to play the best reproductive performance.2,With the increase of dietary fiber levels, plasma Estradiol concentration will be reduced.3,Increasing fiber levels in sow gestation diet was favor to increading liver index,heart index and kidney index of piglets.