Antibiotic Growth Promoters In Broiler Diets Research Articles

Effect of coated sodium butyrate in diet on performance, gut microbiota, ileal digestibility, serum nutrient fractions, immune responses and bone mineral variables in broiler chicken fed antibiotic-free diet

Content Antibiotic growth promoters (AGP) are not recommended in broiler diets due to the possible threat of microbial resistance and residues in meat. Aim Two experiments were conducted to study the possibility of utilising coated sodium butyrate (CSB) as an alternative to AGP (500 g/t) in broiler (1–42 days) chicken diet. Method In Experiment 1, a positive control (PC with AGP), a negative control (NC, without AGP) and CSB diet (150 g/t), and in Experiment 2, four diets, i.e. PC, NC, and CSB at two concentrations (75 and 150 g/t) were prepared. Each diet was offered ad libitum to 10 floor pens (25 broilers) with built up litter as bedding material. Key results Bodyweight gain (BWG) and feed intake (FI) were not affected, while feed efficiency (FE) at both Day 21 and Day 42 reduced in broilers fed the NC compared with those in the AGP-fed group (Experiment 1). Inclusion of CSB (150 g/t) improved the FE similar to the AGP group. In Experiment 2, BWG and FI were not affected, while FE improved in CSB groups compared with the AGP or NC. The colony count of E. coli and C. perfringes increased in the NC group compared with the AGP group and the count in CSB groups was similar to that in the AGP group. The ileal digestibility of nitrogen (CSB150 g) and energy (CSB75 and CSB150 g) and tibia variables (total ash and breaking strength) reduced in the NC group compared with the AGP groups and supplementation of CSB improved all these parameters similar to the AGP group. Conclusions On the basis of the data, it is concluded that CSB (75 or 150 g/t) can be used as an alternative to the AGP (bacitracin methylene disalysilate) in broiler chicken diet. The improvement in broiler performance with CSB in diet could be attributed to the increased ileal digestibility of nitrogen and energy, bone mineralisation and reduction in pathogenic bacterial count (E. coli and C. perfringes) in the gut. Implications Use of AGP in broiler diets can be avoided with inclusion of coated butyric acid, without affecting the broiler performance.

Detrimental Effect of Tannin on Growth Performance, Visceras Weight and Blood Biochemistry in Broiler Chickens Reared Under Tropical Area.

Restriction of antibiotic growth promoters (AGP) in Indonesia reduces broiler production due to bacterial diseases. Some poultry farmers have attempted to replace AGP with phytogenic compounds, such as tannin as an in-feed additive. Therefore, this study was carried out to investigate the effects of tannin administration on the productionperformance, viscera weight, and lipoprotein levels of tropically-raised broiler chickens. Cobb Strain broiler chicks aged one day were used in an experiment with a completely random design, three treatments, and four replicate pens, each containing nine birds. Three dietary treatments were assigned to the birds: basal diet (negative control), basal diet+0.03% Zn Bacitracyn (positive control), and basal diet+0.05% tannin for the starter phase of 1-21 days and the grower phase of 22-42 days, respectively. Tannin supplementation significantly increased the feed conversion ratio in all phases relative to the control group. Tannin supplementation in the diet significantly reduced daily feed intake during the grower phase, final body weight, carcass weight, intestine weight, liver weight, and total visceral weight, compared to the control group. Tannin had lower levels of aspartate aminotransferase but higher levels of low-density lipoprotein and alanine aminotransferase. Tannin addition in broiler diets might not improve growth performance and health. Therefore, it is not suggested as a substitute for AGPs in broiler diets.

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.