The effect of feeding of crushed thyme (Thymus valgaris L) on growth, blood constituents, gastrointestinal tract and carcass characteristics of broiler chickens

Abstract

The effect of feeding of different levels of thyme (Thymus valgaris L) on performance, blood constituents, gastrointestinal tract and carcass characteristics was studied in broiler chickens. An experiment of five dietary treatment groups with different levels of thyme was conducted in broiler chickens from 1 to 42 days of age. Dietary thyme significantly increased body weight and body weight gain, and improved feed conversion ratio. The serum levels of glucose, total protein, and globulin were significantly increased by the addition of thyme. The serum levels of triglyceride and cholesterol were significantly decreased. The lengths of gastrointestinal tract segments were decreased by feeding 1.0%, 1.5% and 2.0% thyme. The same levels of thyme improved dressing and breast percentage of female broilers, and 1.5% and 2.0% thyme feedings improved significantly the leg and wing percentage. Same trends were observed in male broilers. These findings suggest that thyme can be used as a natural growth promoter in broiler rations particularly at 1.5% and 2.0% level. © 2009, Japan Poultry Science Association.