M.R. Reddy

Effect of supplementary choline on the performance of broiler breeders fed on different energy sources.

Abstract 1. Laying performance, egg quality, fertility and hatchability, and fat deposition in liver and abdomen were recorded in broiler breeders (29 to 48 weeks of age) fed on diets containing perarl millet ( Pennisetum typhoides ) (PM), broken rice (BR) or yellow maize (YM) (600 g/kg diet). Constant ratios of metabolisable energy (ME) to other nutrients were maintained in all the diets. Food grade choline chloride (50%) was added to the diets at 3 concentrations (0, 760 and 1520 mg/kg). Each diet was offered to 3 replicate groups of 15 birds (12 hens and 3 cockerels), maintained in deep litter pens, to provide 1.46 MJ ME/bird/d. 2. Neither the source of energy nor dietary choline content had any influence on hen-d egg production, fertility or hatchability. Food efficiency and egg weight were significantly reduced in BR-fed groups compared to those fed on the other energy sources. 3. The efficiency of energy and protein utilisation increased and liver fat content was decreased significantly by dietary choline supplementation. 4. Haugh unit score, egg shell weight, liver weight and intestinal weight were not influenced by either supplementary choline or the source of energy. However, the yolk colour index was significantly reduced in PM- or BRfed groups compared to those fed on the maize-based diet. 5. Deposition of abdominal fat was significantly greater in BR-fed birds compared to those fed on the YM-based diet, while liver fat content was significantly greater in the birds fed on the PM-or BR-based diets than those based on YM. Although supplementation of the diet with choline had no influence on abdominal fat deposition, liver fat content was significantly reduced in birds given diet containing 760 mg supplemental choline/kg diet. 6. The present study indicates that PM or BR can be used as principal energy sources in place of YM in broiler breeder diets without affecting egg production, fertility or hatchability. Liver fat content can be reduced by adding choline at 760 mg/kg to diets based on different energy sources.

Laying performance of broiler breeder chickens fed various millets or broken rice as a source of energy at a constant nutrient intake.

Laying performance, egg quality and carcase traits were recorded in broiler breeders (29–48 weeks of age) fed diets in which pearl millet (Pennisetum typhoides), finger millet (Eleusine coracana), foxtail millet (Setaria italica) or broken rice fully replaced yellow maize (50% of the diet) from the reference diet. Constant ratios of metabolizable energy to other nutrients were maintained in all the diets. Each diet provided 1.38 MJ metabolizable energy (ME)/bird per day to 8 replicate groups of 10 layers each, maintained in deep litter pens.The hen-day egg production and the ME required to produce 12 eggs in birds fed pearl millet or broken rice were similar (p>0.05) to those fed on the maize diet, while birds fed foxtail millet or finger millet required more energy to produce the same number of eggs. The egg production and the efficiency of energy utilization were significantly (p<0.05) reduced in the birds fed these two cereals. Egg quality was not affected by replacing maize with the different cereals. However, the yolk colour index was significantly (p<0.05) reduced in the cereal-fed groups in comparison to the maize-fed birds. The gizzard and giblet weights were heavier (p<0.05) in the birds fed foxtail millet or finger millet than in those fed broken rice. Deposition of abdominal fat and the liver fat content were significantly (p<0.05) higher in the birds fed pearl millet than in the other groups. Depending on the local prices, the cost of feeding may be reduced considerably by using any of the cereals tested as the principal energy source in place of maize in broiler breeder diets.

Differential expression of Toll-like receptor mRNA in White Leghorn and indigenous chicken of India

In the present experiment, the expression profile of Toll-like receptor mRNA in indigenous and pure line chickens was studied. The expression of TLR3, TLR4, TLR5 and TLR7 were quantified in heterophils of Aseel, Kadaknath, Naked neck, Dwarf and White Leghorn lines by Quantitative Real-time PCR. White Leghorns expressed significantly (P < 0.01) higher levels of TLR3 mRNA compared to other lines. TLR4 and TLR5 mRNA were significantly highly expressed in Kadaknath line. Among the TLRs investigated TLR5 was more expressed in all lines studied. TLR7 was highly expressed in indigenous chicken Aseel and Kadaknath than other lines. Dwarf chicken expressed significantly (P < 0.01) lower levels of all TLRs investigated. On the basis of the present study we conclude that the differential expression of TLR mRNA in the heterophils of indigenous and other chicken breeds might contribute to their variable disease resistance/susceptibility.

Toll-like receptor mRNA expression, iNOS gene polymorphism and serum nitric oxide levels in indigenous chickens

Toll-like receptor (TLR) family is one of the important members of innate immune system that recognizes conserved microbial patterns and induces innate immune response. They also act as a link to adaptive immune response. Nitric oxide (NO) is a multi-functional mediator with diverse physiological and immunological roles. In the present study TLR mRNA expression in heterophils, serum nitric oxide level and iNOS (inducible Nitric Oxide Synthase) gene polymorphism were investigated in cockerels of two Indian native chicken breeds, Aseel and Kadaknath. TLR (4 and 5) mRNA expression as quantified by real time RT-PCR revealed Kadaknath males expressed significantly (P < 0.01) higher TLR4 mRNA than Aseel males. iNOS gene polymorphism analyzed by PCR-RFLP method revealed difference in allele frequency. Kadaknath males had higher allele B frequency (0.81) than Aseel males (0.56). However, there were no genotype and breed effect on serum nitric oxide level. Based on the present study we conclude that Kadaknath has comparatively higher innate immunity levels than Aseel, however further investigations are needed.