Point prevalence of bovine fascioliasis and the influence of chemotherapy on the milk yield in a lactating bovine population from the district of Toba Tek Singh, Pakistan

This paper provides an estimation of the point prevalence of fascioliasis and its economic impact in terms of increased milk yield after chemotherapy of a bovine population from the district of Toba Tek Singh, Punjab, Pakistan. A total of 2400 cattle and buffaloes were examined quantitatively using the McMaster egg-counting technique. Infected cattle and buffaloes (50 of each) were randomly selected and each divided into two groups of 25 animals. Groups A (buffaloes) and C (cattle) were treated with oxyclozanide (orally, 16.6 mg kg(-1) body weight). Groups B and D served as negative controls for buffaloes and cattle, respectively. Pre- and post-treatment milk yield was recorded to determine if there were any changes in milk yield after treatment. Of 2400 faecal samples analysed, 654 (27.25%) were positive for Fasciola spp. with a mean number of eggs per gram (EPG) of 503.2. The point prevalence and worm burden of fascioliasis was significantly higher (OR = 2.13; P < 0.05) in buffaloes (34.58%; 415/1200; mean EPG maximum likelihood = 521.4) as compared to that of cattle (19.92%; 239/1200; mean EPG maximum likelihood = 415.8). Among the parasite species, F. gigantica (19.88%; 477/2400) was predominant (OR = 3.12; P < 0.05) as compared to F. hepatica (7.38%; 177/2400). An average daily increase of 0.67 and 0.87 litres of milk, with 0.41% and 0.37% more fat per animal, was observed in oxyclozanide-treated buffaloes and cattle, respectively. The economic value of reduced production of infected animals was estimated as US$0.33 and 0.32 per animal per day for cattle and buffaloes, respectively.