Control of spp. infection by sheep flock owners in Northern Ireland.

Background: To address a lack of information on the control of ovine helminth parasites in Northern Ireland (NI), a number of research projects have been undertaken, dealing with gastrointestinal nematodes, tapeworms and liver fluke. This investigation concerns and concentrates on three aspects of disease: farm management strategies for its control, derived from the results of a Questionnaire; the efficacy of treatment used by farmers, as determined by a coprological survey; and the hatching requirements of eggs, that is, whether prolonged chilling is a pre-requisite for hatching.

Results: A Questionnaire was sent to 252 sheep farmers in NI in March 2012 (covering the years 2009-2012) and replies were received from 228 farmers.

Fasciola hepatica: time-dependent disruption of spermatogenesis following in vivo treatment with triclabendazole.

Sheep infected with the Cullompton isolate of Fasciola hepatica were treated with triclabendazole at a concentration of 10 mg/kg at 12 weeks post-infection. Adult flukes were recovered from the liver and, where present, from the gall bladder at 48, 72 and 96 h post-treatment (pt). Gross changes to the spermatogenic cells of the testis were examined by histology and ultrastructural alterations were visualised via transmission electron microscopy.

Fasciola hepatica: disruption of spermatogenesis by the fasciolicide compound alpha.

Sheep infected with the triclabendazole-susceptible Cullompton isolate of Fasciola hepatica were dosed with 15 mg/kg of compound alpha at 12 weeks post-infection. Adult flukes were recovered from the bile ducts at 24, 48, and 72 h post-treatment (p.t.