Influence of Dietary Levels of Milk By-products in Weaning Diet on Growth Performance, Blood Profiles, Intestinal Morphology and Muscle fiber in Weaning pigs and Economic Analysis

Abstract

his experiment was conducted to evaluate various levels of milk by-products in weaning pig diet on growth performance, blood profiles, intestinal morphology, muscle fiber diameter and diarrhea incidence on weaning pigs. A total of 160 weaning pigs ([Yorkshire × Landrace] × Duroc), average 5.97 ± 1.53 kg body weight (BW), were allotted to one of four treatments in 5 replications with 8 pigs per pen by BW and sex in a randomized complete block (RCB) design. Pigs were fed each treatment diet with various levels of milk by-product (phase 1: 5, 10, 20 or 30%

phase 2: 0, 5, 10 or 15%) for 5 weeks (phase 1: 0-2 week, phase 2: 3-5 week). Growth performance was decreased linearly as milk by-product level decreased during phase 2 and whole experimental period (linear response, P<0.05). However, pigs fed milk by-product 10%-5% diet had similar growth performance rather than pigs fed milk by-product 30%-15%. In blood profiles, there was no significant difference in BUN, IGF-1, IgA and IgG among treatments. The villus height and crypt depth of small intestine (proximal, mid and distal small intestine) had no significant difference among dietary treatments. Also muscle fiber diameter was not affected by milk by-product levels. The incidence of diarrhea had no significant difference by dietary treatments. Consequently, inclusion of milk by-product 10%-5% had no negative influence on growth performance and other measurements compared with inclusion of milk by-product 30%-15%.