Publications

nematodirus infection in lambs on an alternate grazing system of husbandry.	the epidemiology of nematodirus battus infection under a husbandry system based on an annual alternation of sheep and cattle was studied from 1983 to 1985. pasture larval levels and sheep and cattle worm egg outputs were monitored from april to september each year. the level of n battus contamination on the sheep pasture and the number of clinically affected lambs increased over the three years despite grazing with cattle in the intervening year. examination of cattle faeces demonstrated that si ...	1988	3222554
epidemiology of nematodirus battus infection in eastern scotland.	a field investigation was carried out from 1981 to 1983 on the prevalence of nematodirus battus under different systems of lowland sheep management. pasture larval counts, ewe and lamb worm egg counts, and tracer lamb worm counts were carried out. as expected, contamination was generally greater on permanent pasture than on new leys as measured by pasture larval counts and lamb worm egg counts. however significant contamination was also recorded on young grass fields for which alternate grazing ...	1985	4001558
the distribution of the pathogenic nematode nematodirus battus in lambs is zero-inflated.	understanding the frequency distribution of parasites and parasite stages among hosts is essential for efficient experimental design and statistical analysis, and is also required for the development of sustainable methods of controlling infection. nematodirus battus is one of the most important organisms that infect sheep but the distribution of parasites among hosts is unknown. an initial analysis indicated a high frequency of animals without n. battus and with zero egg counts, suggesting the ...	2008	18620622
sheep helminth parasitic disease in south eastern scotland arising as a possible consequence of climate change.	the climate in the uk is changing, with a trend towards increased rainfall in the autumn and winter and warmer average temperatures throughout the year. there has also been a 4-week extension of the herbage growing season over the past 40 years. these changes may have implications for the epidemiology of sheep helminth parasites. here, we describe production-limiting disease outbreaks caused by haemonchus contortus, nematodirus battus, teladorsagia circumcincta and fasciola hepatica in sheep flo ...	2009	19556065
variation in the hatching behaviour of nematodirus battus: polymorphic bet hedging?	previous work on the transmission dynamics of nematodirus battus, an important nematode parasite of farmed ruminants in temperate regions, suggests that it operates a bet-hedging strategy. hatching of cold-sensitised eggs is concentrated in spring, while alternative hatching of non-cold-sensitised eggs in autumn mitigates the risk of poor conditions for hatching in spring or host absence during peak larval availability. isolates from scotland showed much less propensity to hatch without chilling ...	2010	19944106
observations on the epidemiology of autumn nematodirosis in weaned lambs in a scottish sheep flock.	nematodirosis was diagnosed in the south-east of scotland during two consecutive autumns in lambs which were grazed on the same field. the problem was unpredicted based on the knowledge of the pasture and animal management, and rudimentary understanding of the behaviour of free-living stages of nematodirus battus in the region. unlike the epidemiology that has been described in the south of england, whereby autumn infection of lambs is believed to arise from autumn hatching of eggs shed during t ...	2012	22266686