Department of Pathology, College of Veterinary Sciences, U.P. Pt. Deen Dayal Veterinary University and Go-Anusandhan, Kenra, Mathura - 281 001, India.
Immunonopathologicai studies were carried out in a group of sheep fed 1% aqueous solution of copper sulphate @ 40mg/kg b.wt. for 42 days. Humoral Immune response was studied by injecting E. coli 026 bacterin on 10th day and subsequent challenging dose on 20 day of experimentation. Serum agglutination titre were 1:20, 1:20, 1:20 and 1:40 in sheep of toxicity group as compared to 1:80, 1:80, 1:160 and 1:320 in control group of animal on 30th day. CMI response was evaluated by cutaneous application of DNCB (dinitrochlorobenzene) on day 10 and challenging dose on day 25 of experiment. The skin thickness observedon 25th day were 2.300+0.270, 2.625+0.170, 3.550+0.330, 3.300+0.370 and 2.630+0.240 mm in toxicity group and 2.050+0.130, 3.350+0.170, 5.800+0.330, 5.450+0.350 and 4.580+:0.420 mm in control group at intervals of 0, 12, 24, 48 and 72 hrs. of post challenge, respectively. The results have clearly indicated moderate to marked' suppressicn of humoral as well as cell mediated immune response due to chronic copper toxicity in sheep. The mechanism of immunosuppression has been discussed in detail.
Copper toxicity, immunosuppression, sheep
