Effects of dietary fiber supplementation in gestation diets on sow performance, physiology and milk composition for successive three parities

The experiment was conducted to evaluate the effects of dietary fiber supplementation in gestation diets on sow performance, physiology and milk composition for three successive parities. Thirty gilts were assigned randomly to two groups, and fed a basal diet [CON group; 1.10 % soluble fiber (SF), 9.14 % insoluble fiber (ISF)] or a basal diet supplemented with 22.60 g/kg inulin and 181.60 g/kg cellulose [high-fiber (HF) group] during gestation period. The gestation diets provided to sows for three successive cycles averaged 2.28 kg/d from 1 to 112 d for the CON group; and corresponding values for the HF group were 2.75 kg. During lactation and empty, all sows were fed ad libitum a standard lactation diet. Sow body weight (BW) and backfat thickness, litter size and weight, parturition progress, placental weight and lactation feed intake were recorded. In parity 3, plasma samples were collected at gestation day 110 and parturition, and colostrum and milk samples were manually collected on lactation d 0 and 14, respectively. Results showed that averaged over three reproductive cycles, sows fed the HF diet farrowed more piglets born alive (P = 0.049) and litter weight (total born, P = 0.001; born alive, P = 0.001), increased placental weight (P < 0.001), lactation feed intake (P = 0.042), and average weaned pig BW (P = 0.014), and shortened parturition progress (P < 0.05); tended to have higher average pig BW total born (P = 0.092). Reproductive cycle had significant effects (P < 0.05) on sow BW, duration of parturition, placental weight, lactation feed intake, litter size and weight, and average pig BW. An interaction between fiber treatment and reproductive cycle was detected for placental weight. Sows fed the HF diet in parities 2 and 3 had greater placental weight than the other sows (P = 0.007). In addition, sows fed the HF diet had lower (P < 0.05) preprandial low-density lipoprotein and endotoxin concentrations, and greater (P < 0.05) plasma estrogen and lutropin concentrations on d 110 of gestation; had higher plasma oxytocin (P < 0.05) and epinephrine (P < 0.10) levels at farrowing compared with sows fed the CON diet. Colostrum and milk compositions were not influenced by the treatment. Above all, when the daily intake of the basal gestation diet was equalized for both treatments, dietary fiber supplementation to the gestation diet with an equal ISF/SF ratio over three reproductive cycles improved sow and litter performance.