This study was carried out on 16 adult castrated male Baladi goats with age ranged from 1-1.5 years old and weight range of 19±0.82 kg to investigate the biological role of copper deficiency on the modification of immune status and induction of DNA damage. They were randomized into two groups. The first group (six goats) were apparently healthy and kept as control group, whereas the second group (ten goats) were subjected to experimental induction of secondary copper deficiency by dietary addition of Molybdenum ( MO; 10- 40 mg/kg DM) and Sulphur (S; 1.5-3 g / Kg dry matter) daily for 24 weeks. Blood samples were collected without anti-coagulant every six weeks for determination of serum copper and ceruloplasmin activity. Heparinized blood samples were used for assessment of immune status, DNA damage and erythrocyte superoxide dismutase (SOD) activit. Results showed significant decrease (P<0.05) in serum copper, ceruloplasmin and erythrocyte SOD activity starting from 6 weeks to 24 weeks after addition of Mo and S. Goats with experimentally-induced copper deficiency have low serum neutralization antibody index (0.5±0.1) against inactivated rift valley fever vaccine which did not reach the protective antibody level (1.7) compared to that of the apparently healthy control group (1.81 ±0.05) which exceeded the protective value. Lymphocyte blastogenesis response of copper deficient goats was decreased although non significantly in comparison with the apparently healthy control group. The results also showed that copper deficiency caused marked increase in the % of DNA fragmentation of blood cells in goats with experimentally-induced copper deficiency compared to the apparently healthy control group. Goats with experimentally-induced copper deficiency have DNA fragmentation as detected by gel electrophoresis and the DNA ladder represented a series of fragments that is multiples of 180–200 bp. Our findings suggest a significant role of copper deficiency in modulation of immune status and induction of DNA damage and cell apoptosis in goats. Hence, copper level should be strictly considered during formulation of rations in farm animal production practice.
KEY WORDS: Ceruloplasmin, DNA damage, hypocuperosis, Goats, Immunity - lymphocyte blastogenesis, molybdenum, sulpher, superoxide dismutase.