Effects of lysozyme supplementation on performance, nutrient digestibility, intestinal microbiota, and blood profiles of weanling pigs challenged with Escherichia coli
Abstract
This study aimed to evaluate the efficacy of LYS (lysozyme) on growth performance, nutrient digestibility, excreta microflora population, and blood profiles of weanling pigs under Escherichia coli (E. coli) challenge. A total of 30 piglets weaned at 25 days, 7.46 kg body weight, were assigned to three dietary treatments, composed of five replications, two piglets per replication, for 7 days. The dietary treatment groups were negative control (NC; without antibiotics and LYS), positive control [PC; NC + antibiotic 55 mg/kg (CTC-Aureomix)], LYS (NC + 0.1% LYS). All piglets were challenged orally with 6 ml suspension, containing E. coli K88 (2 × 109 cfu/ml). Dietary supplementation with LYS and PC resulted in no significant differences in average daily gain and gain to feed efficiency. Weanling pigs fed with E. coli challenge with LYS and PC treatments had significantly enhanced nutrient retentions of dry matter and energy (p < 0.05); however, there was a tendency to increase nitrogen digestibility. Furthermore, significant effects on excreta, ileal, and cecal of the fecal microbial population as decreased E. coli (p < 0.05) counts with dietary inclusion of LYS and antibiotic, without effects on lactobacillus counts. A significant effect was observed on a white blood cells, epinephrine and cortisol concentrations were reduced in piglets fed diets containing E. coli challenge with LSY and antibiotic supplementation comparison with the NC group. Therefore, the present data indicate that LYS in diet could ameliorate the experimental stress response induced by E. coil in piglets by decreasing intestinal E. coli, white blood cells and stress hormones and improving nutrient digestibility.