Comparison between the effects of two multi-strain probiotics and antibiotic on growth performance, carcass characteristics, gastrointestinal microbial population and serum biochemical values of broiler chickens

This experiment was conducted to evaluate the effect of two types of probiotic and antibiotic virginiamycin on performance, carcass characteristics, gastrointestinal microbial population and Serum biochemical values of broiler chickens. Based on a completely randomized design, three hundred day old Ross 308 broilers were allotted into 4 treatments with 5 replicate pens per treatment and 15 broilers in each pen for 42 days. Dietary treatments were (1) an antibiotic-free corn-soybean meal mash basal diet (control), (2) control + 200 g/ton of virginiamycin, (3) control + 1500 g/ton of fermented probiotic produced and isolated from fermented poultry slaughterhouse wast, and (4) control + 1000 g/ton of commercial probiotic (BioPlus-2B®). The results indicated that the use of antibiotic improved body weight gain (BWG) (7.2 and 8.6 % respectively) and feed conversion ratio (FCR) (3.24 %) as compared to control and commercial probiotic treatments (P<0.05). Also, the birds under virginiamycin treatment had higher feed intake (FI) than those treated with commercial probiotic. The use of fermented probiotic relatively improved BWG (3.28 %) and FCR (1.0 %) as compared tocontrol. Efficiency of dressed carcase, breast, thigh and internalorgans including liver, heart, bursa of fabricius and spleen were notaffected by these experimental treatments (P?0.05). Addingcommercial probiotic to the basal diet increased the relative weightof gizzard than fermented probiotic and reduced the relative weightof abdominal fat pad than virginiamycin treatment (P<0.05). Both ofthese probiotics increased total bacterial population in crop whencompared with virginiamycin (P<0.05). The use of fermentedprobiotic significantly increased the lactic acid bacteria population incrop than antibiotic treatment. Fermented probioticsupplementation significantly lowered the pH of ileum than thosecontrol and antibiotic treatments. Antibiotic virginiamycin andfermented probiotic were effective to reduce ileum coliformspopulation when compared to control and commercial probiotictreatments (P<0.05). The use of commercial probiotic reduced theblood concentration of cholesterol when compared to control birds(P<0.05). The serum concentration of triglyceride and very lowdensity lipoprotein (VLDL) in birds under fermented probioticsignificantly was lower compared to antibiotic treatment. None ofthese fed additives had significant effect on other Serum biochemicalparameters including glucose, high density lipoprotein (HDL), lowdensity lipoprotein (LDL), total protein, albumin and globulin.According to the present study, fermented probiotic has been foundto have a positive effect especially on body weight of broilers. Theuse of fermented probiotic is therefore recommended to effectivelyreplace conventional antibiotics.

Keywords:

Probiotic , Antibiotic , Fermentation , Broiler chicken , Performance