UTTAR PRADESH JOURNAL OF ZOOLOGY

Background: Dietary histidine supplementation has gained attention in poultry nutrition due to its role in enhancing growth performance, antioxidant activity and muscle dipeptide synthesis in broiler chickens. However, the increasing use of plant-based feed ingredients with lower histidine content may limit optimal growth and meat quality, necessitating evaluation of histidine-enriched diets in modern broiler production systems.

Aims: To evaluate the effect of histidine supplementation on growth metrics, nutrient utilization and carcass characteristics of broiler chickens

Study Design: A completely randomized design with four dietary treatments basal diet (control, T1), basal diet supplemented with histidine at levels of 0.05% (T2) , 0.10% (T3) and 0.20% (T4) in feed.

Place and Duration of Study: The study was conducted on the Livestock Farm Complex unit of the College of Veterinary Science and Animal Husbandry, Acharya Narendra Deva University of Agriculture & Technology, Kumarganj, Ayodhya (U.P.), India, for a period of 35 days.

Methodology: Two-hundred-day-old commercial broiler chicks were randomly divided into four groups with five replicates of 10 birds each. The birds were assigned to four dietary treatments: basal diet (control) and basal diet supplemented with 0.05%, 0.10% and 0.20% histidine. Standard feeding and management practices were followed. Growth performance parameters including body weight, feed intake, feed conversion ratio, energy efficiency ratio, protein efficiency ratio, performance index and European broiler index were estimated. A metabolism trial was conducted during the last week of the study to assess the nutrient utilization in birds. At the end of the experiment, one bird from each replicate (5 birds/treatment) was randomly selected and slaughtered for carcass trait studies. Data were analyzed using one-way ANOVA.

Results: Histidine supplementation significantly influenced growth performance of birds. Birds fed 0.10% histidine showed the highest final body weight (1773.60 g), improved feed conversion ratio and superior performance indices compared to control and other groups (P < 0.05). Feed intake was significantly reduced in the higher-histidine-supplemented groups. Nutrient digestibility did not differ significantly among treatments, although numerically higher values were observed in the 0.10% histidine supplemented group. Carcass traits indicated improved breast and back yield in histidine-supplemented birds, while no adverse effects were observed on major organ weights.

Conclusion: Supplementation of histidine at the level of 0.01 % in the diet of broiler chickens improved growth performance and feed efficiency without negatively affecting nutrient utilization or carcass characteristics. Therefore, moderate histidine inclusion can be considered an effective nutritional strategy for enhancing broiler productivity and meat quality.