Biochemical studies on the impact of external and blood parasites on milk production and it`s components in dairy cattle.

External and internal parasites are the major cause of many problems in dairy cattle. This study estimated the association of external parasites infestation and blood parasites infection with milk production and it`s components. Identification and prevalence of ticks, Babesia and Theileria species were carried out on 300 local moderate lactating Friesian cattle .The effect on chemical components of milk and other milk parameters including amount and immune suppression were studied. 75% of dairy cattle were infested with ticks while 9% were infected with Babesia spp. and 10% were infected with Theileria spp . , levels of both calcium and zinc in serum of dairy cattle infested with ticks , infected with Babesia spp. and infected with Theileria spp. were markedly decreased (9.3±0.5, 8.7±0.6 & 9.2±0.7 mg/dl ) respectively for calcium and (0.37±0.001, 0.23±0.001 &0.31±.001 µg/dl ) respectively for zinc . Ig E levels were increased in dairy cattle infested with ticks (1.7±0.03 µ/ml), infected with Babesia spp. (1.1±0.02 µ/ml) and infected with Theileria spp. (1.2±0.02 µ/ml) than clinically healthy ones (0.95±0.02 µ/ml). Significantly decreased Calcium levels in milk of dairy cattle infested with ticks , infected with Babesia spp. and infected with Theileria spp. (144.5±13.8, 129±12.3 & 132±11.4mg/dl) respectively than that of clinically healthy ones (159.4±12.7mg/dl). Also zinc levels in milk recorded decreasing values in dairy cattle infested with Ticks, infected with Babesia spp. and infected with Theileria spp . (8.5±0.07, 6.9±0.8 & 7.2±0.6 µ mol/dl) respectively than that of clinically healthy ones(12.7±0.09 µ mol/dl).