Effect of Energy Levels and Sources on Physiological Responses and Reproductive Performance in Sows

Abstract

Experiment 1. Effect of Dietary Energy Levels on Physiological Parameters and Reproductive Performance in Gestating Gilts The experiment was to investigate the effects of dietary energy levels on the physiological parameters and reproductive performance of gestating first parity sows. A total of 52 F1 gilts (Yorkshire×Landrace) were allocated to 4 dietary treatments using a completely randomized design (CRD). Each treatment contained diets with 3,100, 3,200, 3,300 or 3,400 kcal of ME/kg. Subsequently, the daily energy intake of gestating gilts in each treatment were 6,200, 6,400, 6,600 or 6,800 kcal of ME/kg, respectively. During gestation, the body weight (p=0.04) and weight gain (p=0.01) of gilts increased linearly with increasing dietary energy levels. Backfat thickness at d 110 of gestation was not affected by dietary treatments. There were no significant differences in litter size or litter birth weight. During lactation, the voluntary feed intake of sows tended (p=0.08) to decrease when the dietary energy levels were high during gestation. No difference was observed in the backfat thicknees of sows within treatments but higher energy treatment resulted in decreasing body weight of sows at d 21 of lactation (p<0.05) and body weight gain during lactation (p<0.01). The 3,400 kcal of ME/kg treatment showed the highest number of weaning piglets among treatments (p<0.05). The culling rate was higher in 3,100 (38%) and 3,400 (15%) kcal of ME/kg treatments. No significant differences were observed in the chemical compositions of colostrum and milk. Consequently, the adequate energy intake for gestating gilts should be 6,400 or 6,600 kcal of ME/d.

Experiment 2. Effect of Dietary Energy Levels on Physiological Parameters and Reproductive Performance in Gestating Sows over Three Consecutive Parities This experiment was to evaluate the effects of the dietary energy levels on the physiological parameters and reproductive performance during gestation over three parities in sows. A total of 52 F1 gilts (Yorkshire×Landrace) were allotted to one of four dietary treatments using a CRD. The treatments contained 3,100, 3,200, 3,300 or 3,400 kcal of ME/kg diet but feed was provided at 2.0, 2.2 and 2.4kg/day in the first, second and third parity, respectively. Experimental diets and treatment of sows were not changed during the whole experiment period. The body weight and body weight gain during gestation increased as the dietary energy level increased (p<0.05, and p<0.01) in the first parity. In the second parity, the body weight of sows was the lowest (p<0.05) when 3,100 kcal of ME/kg treatment diet was provided. The body weight was higher as the dietary energy level increased (p<0.05) during the gestation period in the third parity. During lactation, the voluntary feed intake of lactating sows tended to decrease when gilts were fed higher energy treatment diet (p=0.08) and the body weight, body weight gain were increased by dietary energy level during gestation (p<0.05). Backfat thickness was not affected by dietary treatment during the gestation period in over three parity, interestingly backfat change from breeding to d 110 of gestation was higher as the dietary energy level increased at the first parity (p<0.05). When gilts were fed 3,400 kcal of ME/kg treatment diet, higher number of weaning piglet was observed in the first parity (p<0.05). The highest culling rate (69%) was seen when gestating sows were fed 3,100 kcal/kg ME treatment diet during three parities. No significant differences were observed in the chemical compositions of colostrum and milk. In conclusion, the adequate energy intake of gestating sows should be 6,400 or 6,600 kcal of ME/d, 7,040 or 7,260 kcal of ME/d, and 7,680 or 7,920 kcal of ME/d for parity 1, 2 and 3, respectively.

Experiment 3. Effect of Tenebrio molitor Larva as an Energy Source on Reproductivity of Sows and Growth of their Progeny This experiment was conducted to evaluate the effect of Tenebrio molitor larva as a dietary energy source on reproductivity and growth performance of their progeny in lactating sows. A total of 25 F1 sows (Yorkshire×Landrace) were allotted to one of five dietary treatments using a CRD. Various levels of Tenebrio molitor larva were supplemented and treatments were 1) CON (tallow 2%), 2) F1 (tallow 3%), 3) F2 (tallow 4%), 4) L1 (tallow 2% + Tenebrio molitor larva 1%) and 5) L2 (tallow 2% + Tenebrio molitor larva 2%). The body weight, backfat thickness and weaning to estrus interval were not affected by dietary treatments. There were no differences in litter weight and litter weight gain in lactation period among dietary treatments. Lower blood urine nitrogen concentrations were observed in L2 treatment in sows (p<0.01). In nursing pigs, higher triglyceride (p<0.01) and very low density protein (p<0.01) were observed in L1 treatment. In alanine aminotransferase concentration, L1 treatment showed higher concentration than other treatments (p<0.05). Consequently, Tenebrio molitor larva is available energy source instead of tallow in lactating diet and addition of Tenebrio molitor larva as an energy source up to 2% in lactating sow diet did not show detrimental influences on sows performance and growth performance of their progeny.