Effects of Dietary Multi-Carbohydrase and Phytase Complex Supplementation on Nutrient Digestibility, Bone Mineralization and Puberty Onset in Gilts

The study was conducted to determine the effects of multi-carbohydrase and phytase complex (MCPC) supplementation in standard and commercial diets on growth performance, nutrient digestibility, bone mineralization, blood biochemical parameters and puberty onset in gilts. A total of 144 healthy gilts (Duroc × (Landrace × York)) were assigned randomly to four treatments (<i>n</i> = 36), with 10 replicate pens (6 pens, each containing 4 gilts, and 4 pens, each containing 3 gilts). The trial consisted of two phases (phase 1: 70-100 kg; phase 2: 100-140 kg). The commercial diet (COM) had 33% higher calcium (Ca) and phosphorus (P) levels than the standard diet (CON) across all phases. The four treatment diets were as follows: CON (phase 1: 0.56 g/kg Ca and 0.49 g/kg P; phase 2: 0.49 g/kg Ca and 0.45 g/kg P), COM (phase 1: 0.75 g/kg Ca and 0.65 g/kg P; phase 2: 0.65 g/kg Ca and 0.60 g/kg P), CON + MCPC and COM + MCPC, where both the CON and COM diets were supplemented with 100 mg/kg of MCPC, respectively. The commercial diet significantly (<i>p</i> < 0.05) increased the total number of follicles and the number of follicles < 4 mm and tended to reduce (<i>p</i> = 0.07) the age at puberty compared to the standard diet. Besides, MCPC supplementation improved the apparent total-tract digestibility (ATTD) of Ca (<i>p</i> < 0.05), P (<i>p</i> < 0.05) and Ash (<i>p</i> = 0.07) in gilts during phase 1, compared to the basal diets without MCPC supplementation. Additionally, MCPC supplementation significantly elevated serum creatinine (CREA, <i>p</i> < 0.05) concentrations and had a tendency to increase serum Ca (<i>p</i> = 0.07) concentrations in gilts. Specifically, COM + MCPC supplementation significantly increased the osteocalcin (OCN) concentration compared with the COM treatment. Moreover, dietary MCPC supplementation significantly improved the bone strength (<i>p</i> < 0.05) compared to the basal diets without MCPC supplementation. In conclusion, dietary MCPC supplementation increased the ATTD of Ca and P in gilts, while also improving bone strength. This improvement not only extends the reproductive lifespan of sows, but it also allows for reduced supplementation levels of Ca and P in the dietary formula.