The effect of single or combined dietary supplementation of prebiotics, organic acid and probiotics on performance and slaughter characteristics of broilers

A study was conducted to investigate the effect of dietary supplementation of an organic acid, a probiotic or a prebiotic alone or the prebiotic combined with the organic acid or the probiotic on the performance and slaughter characteristics of broiler chickens fed a maize-soya based diet. The six dietary treatments were: a basal diet (negative control) and diets containing 0.5 g mannan oligosaccharide/kg (prebiotic), or 1.0 g formic acid/kg (organic acid), or a probiotic at 0.5 g/kg, or 0.5 g prebiotic/kg + 1.0 g organic acid/kg, or 0.5 g prebiotic/kg + 0.5 g probiotic/kg feed. Each treatment consisted of eight pens with 50 birds per pen (25 male + 25 female). All dietary supplements, alone and in combination improved live weight significantly at both 21 and 42 days of age compared with the control. However, combinations of the prebiotic with either the organic acid or the probiotic had no additive benefit at 21 and 42 days of age in comparison with the prebiotic alone. The feed intake of the birds was significantly increased with prebiotic supplementation at day 21, but not at day 42. Organic acid significantly improved feed conversion ratio at day 21. The combination of prebiotic and probiotic significantly improved the feed conversion ratio at both 21 and 42 days in comparison with the control. At days 21 and 42 bird mortality was significantly higher in the treatments containing organic acid and organic acid with the prebiotic. In the female birds no slaughter traits were affected by dietary treatments. However, liver weight as a percentage of live weight in the male birds was significantly lowered with prebiotic and probiotic supplementation. Prebiotic supplementation with organic acid resulted in a significantly lower weight of the small intestines compared with the control. In general, the different feed additive regimens that include the prebiotic, probiotic, organic acid, prebiotic with organic acid and prebiotic with probiotic improved the growth rate of the birds significantly compared to the control treatment. The significant improvement in feed conversion ratio when the prebiotic and probiotic were supplemented together suggests a synergism between them

Effect of dietary mannan oligosaccharide with or without oregano essential oil and hop extract supplementation on the performance and slaughter characteristics of male broilers

The effects of some alternative feed additives for antibiotic growth promoters on performance and some slaughter characteristics were examined in broilers fed wheat-soya based basal starter and finisher diets. A total of 2160 one-day-old male broiler chicks were randomly allocated to six groups with six replicate pens per treatment. The treatments were the basal diet (Control), and the basal diet supplemented with an antibiotic growth promoter (AGP); a prebiotic, mannan oligosaccharide (Bio-Mos, MOS); an essential oil of oregano (Herb-Mos Oregano, HMO); a plant extract of hop (Herb-Mos Hops, HMH) or a mixture of Herb-Mos Oregano and Herb-Mos Hops (HMOH). There were significant effects of dietary treatments on body weight and feed conversion ratio in the 0 - 21 d period, and on body weight and feed consumption in the 0 - 42 d period. The addition of all experimental additives to the diet resulted in significantly higher body weights as compared to the control treatment at both 21 and 42 days of age. Feed intakes were significantly different between the treatments at 0 - 21 d and 22 - 42 d periods, but not during the 0 - 42 d period. However, during the 0 - 21 d period the broiler chickens that received diets supplemented with AGP, MOS, HMO, HMH and HMOH had significantly better feed conversion ratios than the control group, but this pattern was not sustained during the finisher period (22 - 42 d). Mortality rate, hot carcass yield and relative weights of the small intestines, pancreas, abdominal fat and bursa of fabricius were not affected by experimental treatments. The HMH supplementation increased relative liver weight. These results showed that AGP, MOS and herbal feed additive (HMO, HMH, HMOH) supplementation to a diet provided significant advantages on broiler growth performance through a 42-d growth period. However, the combined supplementation of HMO and HMH did not exert either synergistic or additive benefits on the live performance of the broilers. These results also proved that MOS, HMO, HMH and HMOH improved broiler live performance as well as an AGP in both the starter and through the grower period. Furthermore, outstanding advantages were evidenced for the HMH treatment in particular. Therefore, the MOS, HMO, HMH and HMOH performance enhancer feed additives of natural origin may be considered as potential substitutes for AGP in broiler diets

Performance and egg quality of aged laying hens fed diets supplemented with meat and bone meal or oyster shell meal

Meat and bone meal (MBM) and oyster shell meal (OSM) were supplemented to a basal diet (LMS), either alone or in combination, in order to assess the dietary influences of those complementary Ca sources on performance and egg quality of laying hens. Four hundred and thirty-two Brown-Nick hens, at the beginning of their second production period, were divided into four treatment groups with six replicates each. The final body weight of OSM-fed hens was highest, whereas others did not differ significantly. Hens receiving OSM produced more eggs and egg mass along with considerably greater feed intake than those on all the other treatments. Egg weight was not affected by the treatments except for the lower egg weight of the MBM+OSM treatment. Hens fed a diet supplemented with MBM laid at a rate of 1.14%, 3.66% points lower than those on the control and OSM treatments, respectively. Feed efficiency was not influenced by origin of calcium source. Egg shape index and eggshell weight did not differ among treatments. Eggshell thickness and eggshell breaking strength were higher in hens fed with MBM as compared to control and OSM fed birds. Similar to the tendency in shell quality, MBM inclusion in the diet tended to enhance albumen height and Haugh unit. Dietary treatment with OSM resulted in the highest serum Ca and P concentrations. These results indicate that partially replacing limestone with OSM in the laying hen diet provided significant improvements in egg production performance, whereas most of the egg quality traits were enhanced bydietary supplementation with MBM at 4%.Keywords: Animal by-product, egg shell traits, performance, serum mineral concentratio

Effects of rearing systems on performance, egg characteristics and immune response in two layer hen genotype.

White (Lohmann LSL) and Brown (ATAK-S) laying hens, were reared under organic and conventional cage rearing systems, and the effects of the rearing system on performance parameters, egg production, egg characteristics, and immune response were investigated. For this purpose, a total of 832 laying hens of two commercial hybrids, i.e., 416 white (Lohmann LSL) and 416 Brown (ATAK-S) layers, were used. The experiment lasted between 23 and 70 wk of age. In this study, the white layers yielded more eggs as compared to the brown layers in both organic and conventional production systems. Egg weight exhibited a similar pattern to that of laying performance. However, the total hen-housed egg number for the white birds in the organic system was fewer than that of white birds in the conventional cage facility; conversely, a contradictory tendency was observed for the brown birds. Livability of the white layers in the organic system was remarkably lower (14%) than that of the brown line, whereas the white line survived better (3.42%) than their brown counterparts in conventional cages. The feed conversion ratio of the white hens was markedly inferior in the organic system as compared to that of the white hens in the conventional system, whereas relatively lower deterioration was reported in brown layers when reared in an organic system. The organic production system increased egg albumen height and the Haugh unit in eggs of the brown layers. The yolk color score of organic eggs was lower than that of conventional eggs for both brown and white hens. The egg yolk ratio of eggs from white layers was found to be higher in organic eggs as compared to those obtained in the conventional system. All organic eggs had heavier shells than those produced in the conventional system. Eggs from brown layers had more protein content than eggs from white layers. Neither housing systems nor genotype influenced egg yolk cholesterol concentration. When compared to conventional eggs, n-3 fatty acid content was lower in organic eggs, and the n-6:n-3 ratio was higher in organic eggs. In conclusion, two hen genotypes showed different responses in terms of performance and egg quality to two different rearing systems. A commercial white strain produced more eggs with higher egg quality as compared to a native brown strain. The brown strain was found to have adapted well to organic production conditions when survival and total egg number was taken into consideration