Abstract:
This study was aimed at assessing the extent to which probiotics are used in the poultry feed industry in Kenya and their efficacies in broiler diets. In experiment 1, two surveys involving
100 Agro Vets and 36 Poultry farmers were carried out. 16 products were being sold as probiotics in Agro Vets in Kiambu County. The actual trade names of the probiotics are coded as Products 1 to 16 (see Appendix 3). It was found that 74.4% of the farmers used probiotics. The most commonly used by farmers were Products 1, 2, 4 and 7 at 23.1 %, 12.8 % 20.5 % and 15.4
% respectively. In the second experiment, 307, day-old broiler chicks were randomly assigned to
5 dietary treatments and fed for 42 days broken into two phases (starter phase, 0-21 days: finisher phase 22-42 days). These diets were; Diet 1 (Control with no probiotic), Diet 2 (with Product 1), Diet 3 (with Product 4), Diet 4 (with Product 7) and Diet 5 (with Product 2). During the finisher phase, the 5 diets were identified as diets 6-10 where the only differences were the levels of CP being 21.9% and 19.8% for starter and finisher diets respectively. The data were analyzed using GLM procedures of SAS version 9.00. The LSD method at a level of (P<0.05) was used to separate means. The results showed that probiotics had no effect (P>0.05) on daily gain, feed intake and feed efficiency during both the starter and finisher phases except that Product 2 depressed growth. In this experiment, blood samples were collected to measure the effects of probiotics on antibody response to Infectious Bursal Disease virus and the results showed no significant effect (P=0.6868) associated with probiotics. Additionally, the antibiotic properties of the probiotics were tested using the disk diffusion test by measuring the inhibitory effects on Escherichia coli, Staphylococcus aureus, Bacillus cereus and Candida albicans bacterial cultures. Two of the probiotics (Products 4 and 7) showed inhibitory effects on the cultures indicating that they either produced antibiotic compounds or that antibiotics had been added to these products. It is concluded that probiotics are used in Kenya although their inclusion in this experiment had no effect to performance and immune responses. However, two of the probiotics tested had antibiotic properties and research should be carried out to establish the origin of the antibiotic properties. Furthermore, more in depth studies should be undertaken to not only establish the micro-organisms in the probiotics and their effects on immune response while examining the mucosal, cellular and humoral immunities under stressful conditions.
