Nematodiriosis and spring teladorsagiosis in lambs
Sargison, N.D.; Mitchell, G.B.B.; Jackson, F.; Gilleard, J.S.
Veterinary Record 152(25): 788
2003
ISSN/ISBN: 0042-4900 PMID: 12846297 Document Number: 566654
The following article reports on outbreaks of nematodirosis occurring at the end of May in 7- to 10-week-old low ground lambs in the southeast of Scotland. Diagnoses were supported by mean faecal Nematodirus battus egg counts ranging between 500-1500 epg and the identification of large numbers of adult and larval helminths within the small intestine. In many of the nematodirosis outbreaks investigated on the same year, mean faecal trichostrongylid egg counts of 500-1400 epg and large numbers of abomasal Teladorsagia circumcincta helminths were also identified. Teladorsagiosis in 8- to 10-week-old lambs was associated with the overwinter survival of large numbers of third stage T. circumcincta larvae on pasture. The simultaneous occurrence of nematodirosis and spring teladorsagiosis give cause for concern. The high faecal trichostrongylid egg counts of many lambs during May suggest that pastures will remain heavily contaminated for the remainder of the grazing season. Traditional suppressive methods of helminth control may, thus, prove ineffective, and alternative strategies such as the use of safe grazing or of persistent anthelmintics should be considered.