Effects of cashew nut testa levels as an alternative to wheat bran in gestating sow diets

Objective This study was conducted to evaluate the effects of dietary cashew nut testa (CNT) as an alternative feed ingredient to wheat bran on reproductive performance, litter performance, milk composition, and blood profiles of gestating sows. Methods Forth multiparous sows (Yorkshire×Landrace) were fed experimental diets starting at 35 days of pregnancy and an initial average body weight (BW) of 211.53±8.86 kg. Each sow was assigned to a treatment based on BW, backfat thickness (BF) and parity with 10 sows per treatment. Treatments were as follows: i) corn-soybean meal based diet with 6% of wheat bran (C0); ii) basal diet with 2% of CNT and 4% of wheat bran (C2); iii) basal diet with 4% of CNT and 2% of wheat bran (C4); and iv) basal diet with 6% of CNT (C6). Results There were no statistically significant differences in BW and BF of gestating sows throughout the experimental period. However, changes in BF (p = 0.09) and the daily feed intake of sows (p = 0.09) tended to linearly increase during the lactation period. The weaning to estrus interval (WEI) showed a quadratic response to CNT treatment (p = 0.02), and the C2 diet showed the shortest WEI. Litter birth weight (p = 0.04) and piglet birth weight (p = 0.06) were linearly decreased with increase in CNT. Furthermore, there had no significant differences in piglet weight and litter weight in 21 day. Insulin concentration at day 70 of gestation was linearly reduced with increasing CNT level in diets (p = 0.03). Conclusion When 6% CNT replaced wheat bran in gestating sow diets, there were no negative effects on sow performance, but litter birth weight and piglet birth weight were decreased when CNT level increased in gestating sow diets.