Clinical and haematological study on water buffaloes (Bubalus bubalis) and crossbred cattle naturally infected with Theileria annulata in Sharkia province, Egypt.

This study was conducted to investigate the clinical and haematological findings in water buffaloes and crossbred cattle naturally infected with Theileria annulata with special reference to the clinical picture of tropical theileriosis in Egyptian buffaloes. A total 50 field cases of buffaloes and cattle was clinically and laboratory investigated from March to June 2008. Forty-four buffaloes and cattle out of 50 were naturally infected with T. annulata and showed typical signs of infection. Six animals showed no clinical signs and were free from external, internal, and blood parasites. The clinical findings of examined cattle and buffaloes showed typical signs of tropical theileriosis: fever, enlargement of the superficial lymph nodes, severe lacrimation, bilateral conjunctivitis, photophobia, and corneal opacity. It was clear that the severity of clinical signs in infected buffaloes was more prominent than in infected cattle with persistence of some lesions after recovery as corneal opacity and pulmonary lesions. Haematological analysis revealed a significant decrease in RBCS count, PCV%, haemoglobin amount, and WBCs in the infected animals when compared to the control group. It was concluded from our study that T. annulata infection is associated with impairment and alteration of blood parameters in both cattle and water buffaloes. Theileriosis in water buffaloes might cause irreversible ocular changes that could lead to complete blindness. Data obtained in this study might be the basis for subsequent studies under natural and experimental field conditions.