Document Type : Research Paper
Authors
1 Department of Animal Science, Faculty of Agriculture, Urmia University, Urmia, Iran
2 Master's Student of Poultry Nutrition, Department of Animal Science, Urmia University, Urmia, Iran.
3 Department of Chemistry, Faculty of Chemistry, Urmia University, Urmia
Abstract
The present experiment was conducted with the aim of investigating the effect of different levels of thyme powder on performance, egg quality traits and internal quality of eggs at different storage temperatures in old laying hens. For this purpose, 144 laying hens (Hy-line-W36) with similar body weight at the age of 65 weeks were used in a completely randomized design with 3 treatments, 6 replications and 8 birds per replication. The experimental treatments included 1- control treatment (diet based on soy-corn meal without thyme powder), 2- treatment containing 0.25% thyme powder and 3) treatment containing 0.5% thyme powder. At the end of the experimental period (8th week of the experiment), 6 eggs were selected from each replicate and kept at temperatures of 4 and 25 degrees Celsius for 30 days to determine the internal quality. The results showed that laying hens fed with diets containing 0.25 and 0.5% thyme powder had more egg weight than the control group (P<0.05). Egg mass and feed conversion ratio in the 0.5% thyme powder treatment were significantly higher and lower than the control treatment respectively (P<0.05). At a temperature of 25°C, the use of 0.5% thyme powder increased the yolk height and egg yolk index compared to the 0% group (P<0.05). In general, it is recommended to add 0.25 and 0.5% of thyme plant powder to the diet of old laying hens due to the improvement of egg weight, feed conversion ratio, internal quality of eggs and maintaining the quality of eggs during storage.
Keywords
Main Subjects
)