EFFECT OF ULTRAVIOLET EXPOSURE ON PRODUCTIVE, REPRODUCTIVE, PHYSIOLOGICAL PERFORMANCE AND IMMUNE RESPONSE OF LAYING HENS

Abstract

The current study was carried out in Inshas Poultry Breeding Station belonging to Animal Production Research Institute, Agriculture Research Center, Ministry of Agriculture, Giza, Egypt, during the period from July to the end of November 2015. One hundred and sixty five chickens from each developed local Strains (Silver Montazah and Matrouh) (150 females and 15 males), 20 weeks old were used in this experiment up to 40 weeks of age. They were housed under open system during the whole experiment period. All bids were weighed and randomly distributed into five treatments with three replicates per treatment (10 females and 1 male / replicate). Feed and fresh water were provided ad libitum during the experimental period. The first group (control group) was exposed to the natural day light, while the second, third, fourth and fifth groups were exposed to the same lighting system but with supplemental 1, 2, 3 and 4 hours respectively exposure to ultraviolet type A irradiation (UVA) with wavelength up to (368 nm) from UV lamps after sunset, by using controlled timer. All hens were housed under similar managerial and sanitary conditions. The following measurements were taken: - Productive performance including live body weight, feed consumption, feed conversion ratio, egg number, egg weight, egg mass, egg production number, external and internal egg quality traits. Physiological parameters including some blood constituents (i.e. total protein, albumin, Globulin, uric acid, Creatine, Calcium, phosphorus, some blood enzymes (ALT, AST) as liver function indicators. Thyroid hormone (T3) level and Follicle Stimulating Hormone (FSH) were also measured. Some hematological parameters like Hemoglobin, Red and White blood cells, packed cell volume (PCV). Immune response against Sheep red blood cells (first and second