ABSTRACT In the present study, we investigated the effects of acidified dried whey and acidified yeast product and their combination on broiler growth characteristics, intestinal microflora and gut morphology. Seven hundred and fifty day-old Ross 308 male broilers were fed one of 10 dietary treatments with 5 replicates in a randomized design. A corn-soybean meal based diet (control group) was supplemented with 3 levels (0.15, 0.30 and 0.45%) of acidified whey powder (AW), acidified yeast product (AY), and acidified whey powder and yeast product (AWY). Acidified yeast product improved ADG and FCR at d 42, but the effects of additives on productive performance were not significant across the entire rearing period. The highest level of AY increased the population of Lactobacillus spp., decreased that of E. coli and did not affect the bacterial total count at d 42. Birds fed 0.45% AY showed higher villus height and better gut morphology compared to control birds. In conclusion, acidified yeast product increased the population of Lactobacillus, inhibited the growth of E. coli and improved gut morphology and structure, but did not affect growth performance and relative organ weight.

Abstract An experiment was conducted to investigate the effects of hydroalcoholic extract of Withania coagulans (WC) fruit and 1.25-dihydroxycholecalciferol (1.25-(OH)2 D3) on bone mineralization, mechanical and histological properties of male broiler chickens at 21 and 42 d of age. A total of six hundred male day-old Ross 308 broiler chickens were randomly distributed according to a completely randomized experimental design in a 2×3×2 factorial arrangement with 12 treatments of five replicates of 10 birds each. Treatments consisted of two basal diets (positive control with adequate Ca level and negative control with 30% less Ca), three levels of WC (0, 100, or 200 mg/kg diet), and two levels of 1.25-(OH)2 D3 (0 or 0.5 µg/kg diet). Birds were housed in floor pens. The diets were fed ad libitum from one to 42 days of age. On day 21 and 42, one bird per replicate was sacrificed and its tibiae were removed. Both Ca and P retention increased when dietary Ca level was reduced (p<0.001). The addition of 200 mg WC/kg to positive control diet increased Ca retention (p<0.01). Except for tibia diameter, no significant main effects of experimental treatments were observed on tibia physical characteristics or on bone mineralization. The diet with 30% Ca reduction decreased tibia diameter at 42 days of age (p<0.05). The dietary addition of 1.25-(OH)2 D3 increased tibia fracture energy, width of tibia mineralized zone, and serum Ca at 42 days of age (p<0.05). At 21 days of age, supplementation of 100 mg WC/kg increased cortical thickness (p<0.05). At 42 days of age, supplementation of 100 mg WC/kg increased tibia shear force (p<0.05) and fracture energy (p<0.01). The results of this experiment showed that supplementation of 100 mg/kg hydroalcoholic extract of WC fruit increased tibia cortical thickness, shear force, and fracture energy.

Six hundred Ross 308 male broiler chickens were used to study the effect of licorice extract and the prebiotic, fermacto, on performance, blood metabolites and gastro-intestinal transit time (GTT) of feed in the birds. The birds were fed according to a three phase feeding programme on a starter, grower and finisher diet during the ages of 1 - 14 day, 15 - 35 days and 35 - 49 days of age, respectively. The basic diets during each phase contained either 100 or 95% of recommended digestible amino acid (RDAA) concentrations. The two basic starter diets were divided into five treatment diets: No supplement (control); and supplemented with 2.0 g fermacto/kg; and 2.0 (high); 1.0 (medium) and 0.5 (low) g licorice extract/kg diet. In the grower diets half the levels of these supplements were included, while the two finisher diets were fed without containing any of the experimental supplements. There was not a significant difference in body weight, feed intake and feed conversion ratio between the birds fed the control and the diets supplemented with the prebiotic or the different levels of licorice. However, birds receiving diets containing licorice extract had lighter abdominal fat pads compared to those fed the prebiotic or control diets. Blood cholesterol concentrations decreased significantly in birds receiving the high level of licorice in their starter and grower diets as compared to the control. The GTT of feed in the birds fed diets containing the prebiotic or licorice extract did not differ from that of the birds in the control. A 5% reduction in dietary RDAA concentration caused an increase in feed conversion ratio of chickens on the starter and grower diets and for the total duration of the experiment.