FEED ADDITIVE VINIVET OF APICULTURAL PRODUCTS AS AN ALTERNATIVE FOR ANTIBIOTIC GROWTH PROMOTERS IN BROILER CHICK DIETS - BACTERICIDAL AND BIOSTIMULATING EFFECT
Preservation of national gene pool requires the maintenance of quality standards of life including healthy nutrition. In this relation there is a particular public concern about the use of antibiotic growth promoters (AGPs) as an essential part of intensive technologies of animal production, the remnant of the past when it was a commonplace. WHO reported the constant growth of microbial resistance partly due to the transfer of AGPs into animal food products; it could enhance the distribution of bacteria resistant to antibacterial drugs and drug-resistant diseases hazardous for human race. The distribution of these infections among animals (especially breeding flocks) is also hazardous. This hazard is probably underestimated as a result of the lack of knowledge on composition and possible changes in animal and human microbiome including microorganisms undetectable by classic microbiological methods but forming the basis of the microbiota. Another underestimated possibility is the transfer of beneficial biologically active substances to human via animal food products when undesirable ingredients of animal feeds are simply substituted by harmless and biologically active ones, while more costly approaches to production of functional animal foodstuffs are widely discussed. Problem solving must be rapid, economically and biologically effective and safest for human, animals, and environment. In our trials conducted on 3 groups of Cobb-500 broiler chicks (from 1 to 35 days of age) the possibility of substitution of feed additive Vinivet for AGPs in diets for broiler chicks was studied. This additive based on apicultural products, i.e. bee-bread (ambrosia) and slumgum, was produced by no-waste technology (JSC Rusoborotexport, Kazan, Russia) preserving biologically active compounds from these products. It was found that inclusion of Vinivet into broiler diets (5000 ppm) improved live bodyweight in group 3 compared to control group 1 (no Vinivet) by 0.61 and 0.86 % at 28 and 35 days of age, respectively; feed conversion rate (FCR) in group 3 was better by 3.15 % compared to control. AGP Stafac 110 (Phibro Animal Health Corp., USA) fed to group 2 (180 ppm) was found to improve growth rate of broilers compared to groups 1 and 3. Live bodyweight in group 2 was higher than in control at 6, 14, 21, 28 and 35 days of age by 2.63; 1.99; 3.22; 0.51 and 2.04 %, respectively, while FCR in group 2 was better by 3.53 %. The analysis of intestinal microbiota with the use of T-RFLP (Terminal Restriction Fragment Length Polymorphism) method showed substantial decline in pathogenic and opportunistic populations in broilers of Vinivet-fed group 3. The counts of Staphylococcaceae, Fusobacterium spp., Pertococcaceae and Pasteurellaceae were significantly lower compared to control (by 0.91; 0.79; 1.85 and 3.37 %, respectively) while total count of cellulolytic bacteria was higher by 7.94 %. Histological study of liver and intestine showed structural changes in small intestine of Vinivet-fed broilers improving its absorbing ability, barrier and motor functions. The height of intestinal villi in group 3 was significantly higher compared to control, density and depth of crypts were higher as well as the total absorbing surface area. To the contrary, in Stafac-fed group 2 the decrease in thickness of mucosa of intestinal wall was found which could mean the decrease in intestinal functionality. The activation of trophic processes in liver was also found in Vinivet-fed broilers. The histological analysis of liver showed the absence of hepatotoxic effect of Vinivet for broilers. The results of our trial proved Vinivet to be a promising and safe feed additive for poultry.