Comparative effects of replacing soybean meal in feeds with processed soybean meal on intestinal health and growth of nursery pigs when fed pharmacological level of zinc.

OBJECTIVE

The objective was to evaluate the effects of partially replacing soybean meal (SBM) in nursery pig diets with enzyme-treated soybean meal (ESBM), fermented soybean meal (FSBM), or fermented soybean meal containing probiotic microorganism (PFSBM) on jejunal mucosa-associated microbiota, immune responses, intestinal morphology, and growth performance of nursery pigs.

METHODS

Forty-eight weaned pigs (initial body weight = 7.8 ± 0.7 kg) were randomly allocated to four dietary treatments in a randomized complete block design and fed for 25 d in three phases (5, 10, and 12 d, respectively). Dietary treatments were corn-SBM-based diet (SBM diet) and the SBM diet in which 70 g/kg of SBM was replaced with ESBM (ESBM diet), FSBM (FSBM diet), or PFSBM (PFSBM diet). Zinc oxide was supplemented at 2.5 g/kg (2,000 mg/kg of zinc) in the experimental diets for phases 1 and 2. Pigs were housed individually in pens (1.50 m×0.74 m) equipped with a feeder and a nipple drinker. Serum was collected on d 24 and pigs were euthanized on d 27 to collect tissues and mucosa in the jejunum.

RESULTS

The PFSBM diet increased (p<0.05) the relative abundance of Lactobacillus, whereas it tended to decrease (p = 0.072) the abundance of Pseudomonas compared with the SBM diet. The ESBM diet increased (p<0.05) gain to feed ratio from d 5 to 15 compared with the SBM diet. However, partially replacing SBM at 70 g/kg with ESBM, FSBM, or PFSBM did not affect immune responses in serum and jejunal mucosa, intestinal morphology in the jejunum, and overall growth performance of nursery pigs.

CONCLUSION

Partially replacing SBM with various processed SBM did not affect immune responses, intestinal morphology, and overall growth performance when diets were supplemented with zinc at pharmacological level in early phases.