| 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 duri ... | 1988 | 3354055 |