By: Kamlesh Kumar Dhawal
Veterinary Officer, Department of Animal Husbandry, Bikaner (Rajasthan), India
Introduction:
Theileriosis is one of the major constraint to the dairy industry and causes devastating losses to the livestock worldwide. Theileriosis is caused by T. annulata and is transmitted through Ixodid tick. It has been considered as the most important blood protozoan parasite in the most of the region of India. Though all breeds of cattle are equally susceptible to theileriosis, the purebred, exotic, their cross breeds as well as the young indigenous calves are highly susceptible to this disease. To become infected by Theileria, a cow must be bitten by a tick carrying the disease. It is not spread by direct animal to animal contact.
Clinical sign of theileriosis:
1. High rise of temperature
2. Enlargement of superficial lymph node especially of neck region
3. Pale or yellow whites of eyes (a sign of jaundice)
4. Lethargy – exercise intolerance, calves lagging on the walk to the shed
5. Dullness, anorexia, salivation, lacrimation and discharge from nostrils.
6. Respiratory distress, petechial on conjunctiva, unilateral and bilateral
exophthalmia.
Diagnosis of theileriosis:
1.Access clinical sign: High raised temperature with superficial lymph node swelling.
2.External examination of animal: Ticks infestation with above mentioned signs.
2.Laboratory examination of blood: The cases were suspected for haemoprotozoan diseases and the blood samples were collected with EDTA from the calves. The blood smears were stained with Giemsa’s and examined for the presence of haemoprotozoan parasites.
Treatment of theileriosis:
The affected animals are treated with Buparvaquone (Butalex at the dose rate of dose 2.5 mg/kg body weight) intramuscularly and to repeat after seven days.
In addition, meloxicam (Melonex at dose rate of dose 0.5 mg/kg body weight) intramuscularly for three days. The calves are recovered and attains normalcy after one week of treatment.
Prevention and control of theileriosis:
Cattle are at risk of infection when moved to areas where infected ticks are present. Infected animals can also spread the infection to ticks when transported to new areas. In turn, this can spread the disease to uninfected animals.
Tick control is important during the risk period. This is commonly mid-August to mid-March, but as long as the mean air temperature is above 7˚C ticks will be active to some degree. Tick control is also important during periods of stress.
• New arrivals and returning stock should ideally be quarantined for at least 7 days to check and treat ticks.
• Ensure all stock being transported to new areas are healthy and free from ticks.
• Apply tick control products during the risk period. Like Flumethrin and Python for cows.
• Treat other animals (hosts) on the farm for ticks.
