The effect of a subclinical infestation of Nematodirus spp. upon the liveweight gain of lambs

Abstract

Extract

An acute disease condition in lambs associated with heavy Neinatodirus, burdens first attracted attention when outbreaks reached serious proportions in Britain in 1951. The disease was described by Kingsbury (1953) who reported the results of investigations into outbreaks in Berwickshire, Northumberland, and adjoining areas. Sincethat time, other reports from the British Isles (Stamp et al., 1955; Thomas and Stevens, 1956; Baxter, 1957a, 1957b, 1958; Spedding etal, 1958; Black el al., 1958; Gibson, 1958, 1959a, 1959b) have added further information on the pattern of field outbreaks and clinical aspects of the disease. To date, the work on Neinatodirus infestation has been mainly concerned with the acute disease condition, epizootiology and life cycle studies, with little attention being given to the possible effects of subclinical infestations with this parasite.