A Study on effectiveness of a cocktail of protected feed additives in growing pigs

Abstract

The objective of the study was to determine the effects of mixer of protected feed additives (MFA) on growth performance, blood metabolites, fecal microflora counts, and immune responses in growing pigs. A total of 150 pigs [(Landrace×Yorkshire)×Duroc] with an initial body weight (BW) of 25.61 ± 0.01 kg were used in a 4-week feeding trial. Pigs were allotted to one of five diet groups (basal diet supplemented with 0%, 0.35%, 0.75%, 1.50%, or 3.0% of MFA with 6 replicates per group and 5 pigs/replicate). Inclusion of MFA tended (P=0.085) to results in a linear increase in BW at week 4 and overall average daily gain (ADG, P=0.064). However, MFA inclusion had no effect on average daily feed intake or gain:feed ratio during the entire experiment period. When 3% MFA was added to the diet, reduction was observed for cortisol level (P=0.032) and low-density lipoprotein cholesterol (P=0.008) at 4 weeks after dietary treatments. The inclusion of MFA had positive effects on fecal score at week 3 and 4 (P=0.068, 0.023, respectively) and the count of Lactobacillus was increased at the end of week 1 and 4 (P=0.099, 0.014, respectively), whereas for E. coli decreased at the end of week 1 and 4 (P=0.043, 0.067, respectively). Type O antibody titres against foot-and-mouth disease virus (FMDV) in growing pigs fed diet supplemented with MFA (1.5%) was significantly (P=0.008) higher than other dietary treatment groups. In conclusion, inclusion of MFA in growing pigs diet may improve ADG, beneficial fecal microflora counts and FMDV type O antibody titre after vaccination and reduced cortisol level, LDL/C and incidences of diarrhoea.