Epidemiology of ovine helminthiasis in Haryana, India.

Tracer lambs were used to study the pasture contamination with infective stages of helminth parasites during one annual cycle in a subtropical climate. Post-mortem worm counts indicated that low infections with Haemonchus contortus occurred throughout the year except in June. However, twenty five or more H. contortus per lamb were recorded in January, April, May and August. Trichostrongylus colubriformis infection was detected throughout the year and 150 or more worms per lamb were recorded during January to May and in August. Anoplocephalids were recorded from the lambs throughout the year but had no seasonal pattern. Low infections with Oesophagostomum columbianum and Trichuris ovis were observed. The faecal egg counts from the permanent flock with whom the tracer lambs were grazed revealed heavy to mild worm burdens throughout the year. Coproculture indicated that H. contortus predominated from the second fortnight of May to December except in the second fortnight of July. Infection with T. colubriformis was more severe from January to the first fortnight of May and in the second fortnight of July. Negligible infections with O. columbianum, Bunostomum trigonocephalum, Gaigeria pachyscelis and Dictyocaulus filaria were also observed. Biohythergraphs prepared for H. contortus and T. colubriformis showed differences between observed and expected results. It is suggested that for realistic biohythergraphs related parameters in addition to rainfall and temperature should also be considered.

Incidence of sarcoptic mange in buffaloes in India.

The incidence of sarcoptic mange in buffaloes with respect to age, sex, relative humidity and temperature was studied at veterinary clinics and breeding farms in Hisar, India. The disease is more common in animals below the age of one year (19.57%) and decreases with the advancement of age i.e. 3.4% at one to five years and 5.3% in the over five years group. Sex has no bearing on the incidence of the disease. Since female buffalo calves get more attention at the hands of small farmers they are presented more frequently at the veterinary clinics. Fluctuations in environmental temperature affect the incidence of the disease. However, relative humidity showed no correlation. Seasonal incidence at the organised farms was erratic due to the ad hoc treatment to control mange. There is an indication that the winter season is most conducive for the spread of the disease (51.0%), followed by post-monsoon (41.3%), summer (23.1%) and rainy season (11.1%).

Evidence of cell mediated immune response in infection with Eimeria bareillyi in buffaloes.

Delayed dermal hypersensitivity and leucocyte migrations were measured in buffalo calves experimentally inoculated with Eimeria bareillyi. Dermal hypersensitivity, characterized by increased thickness and local inflammation, was observed in calves inoculated intradermally with E. bareillyi antigen on Days 21 and 28 after infection. The highest inhibition of leucocyte migration was observed in infected buffalo calves on Days 21 and 28 post-infection.

Chemotherapeutic efficacy of sulphadimidine, amprolium, halofuginone and chloroquine phosphate in experimental Eimeria bareillyi coccidiosis of buffaloes.

Sulphadimidine, amprolium, halofuginone and chloroquine phosphate were administered to buffalo calves 10 days after experimental infection with Eimeria bareillyi. Animals given sulphadimidine or amprolium remained clinically normal and shed only a few oocysts in their faeces. Halofuginone was found partially effective and chloroquine phosphate completely ineffective in preventing faecal oocyst discharge and intestinal lesions. Sulphadimidine and amprolium treated calves gained weight, but chloroquine treated calves suffered progressive weight loss similar to that of infected untreated controls. No significant alterations of haematological values were observed either in the treated calves or in the untreated controls.