Abstract
The feeding trial was conducted for 4 weeks on 48 Lohmann Brown layers (55 weeks) in order to evaluate the effect of a natural oil blend (OB) on intestinal microflora population. The trial was conducted in experimental halls with controlled microclimate (average temperature/total period 22.41±0.98°C; humidity 66.35±5.68%; ventilation/chick 0.50±0.24%; CO2 level 686.39±104.38 ppm) and 16h/day light regimen. The layers assigned to 2 groups (24 hens/group, 4 hens/cage) received a conventional diet with the same basal formulation (16.80% crude protein; 2760 kcal metabolizable energy). The new formulations diet for the experimental (OB) group differed from the conventional diet C, by replacing the vegetal oil with a OB (0.50%). The compose of the OB was 20% buckthorn oil, 20% sesame oil, 20% rosehip oil, 20% grape oil and 20% walnut oil. At the end of the trial, 6 layers/group were slaughtered and samples of caecal and intestinal contents were collected for bacteriological examination. The colony forming units (CFU) of Escherichia Coli and Staphylococcus spp. in the caecum content in OB group was significantly (P≤0.05) decreased (10.02 and 8.33 CFU) compared with C group (10.09 and 9.12 CFU). Same trend was observed in the intestinal content, Escherichia Coli and Staphylococcus spp. decreased significantly (P≤0.05) in OB group (5.39 CFU Escherichia Coli and 5.24 CFU Staphylococcus spp.) compared with C group (5.41 and 5.25CFU). Lactobacillus spp. the favourable bacteria in the caecum and intestine content, was increased significantly (P≤0.05) in OB group (10.96 and 6.17 CFU) compared with that in C group (10.53 and 6.09 CFU). Salmonella was absent in all cases.