Influence of Light on the Hematology, Lymphoid Organs and Production of the Broilers

Effect of light stress at various time intervals on broiler chicks was studied during JanuaryFebruary, 2010 by rearing a total of 400, one-day-old Hubbard X Hubbard experimental chicks at Department of Microbiology, University of Veterinary and Animal sciences, Lahore, Pakistan. It was observed that light stressed birds had showed non-significant (P>0.05) difference on blood cells population except lymphocytes percentage was found higher in groups D (61.4+1.16) than group C. The effect on lymphoid organs studied and the mean thymus weight (gm) of chicks in group B (1.90+0.53) was adversely effected as the chicks in this group had significantly (P<0.05) lower mean thymus weight than groups D (4.64+0.74) and E (4.34+0.25) indicating that increase in the period of off-light in chicks adversely effected the mean thymus weight and chicks reared on 24hr light had higher mean thymus weight. The bursa mean weight (gm) of group B (0.43+0.05) was significantly (P<0.05) lower as compared to group D (1.59+0.17). The spleen mean weight (gm) of group D (1.88+0.15) was significantly (P<0.05) higher than group B (1.18+0.08). The FCR values were significantly (P<0.05) different among groups in 6 week and there was non-significant (P>0.05) difference among groups with treatment of Vitamin C, Vitamin E and glucose.