Ecology of gastropod and bighorn sheep hosts of lungworm on isolated, semiarid mountain ranges in Utah, USA.
J Wildl Dis
; 44(1): 28-44, 2008 Jan.
Article
em En
| MEDLINE
| ID: mdl-18263819
ABSTRACT
Isolated, nonmigratory populations of bighorn sheep (Ovis canadensis) may experience high exposure to lungworms (Protostrongylus spp.) through a build-up of fecal material. However, semiarid climates may hinder lungworm transmission by limiting terrestrial gastropods, the intermediate hosts. We assessed potential for lungworm transmission, documented occurrence of transmission, and identified habitat types where transmission was likely to occur on ranges of two recently introduced populations of bighorn sheep in northern Utah. Gastropods were collected weekly on Antelope Island and the Newfoundland Mountains, May-August 2001-02, from each of the four major habitat types (riparian, rock, desert shrub, and grass). Distribution of 113 bighorn sheep groups was observed, and 421 fecal pellet groups were collected to estimate lungworm levels. A total of 1,595 gastropods representing five genera were collected from both ranges. Vallonia made up 85% of all gastropods collected. Of 980 gastropods collected on Antelope Island in 2002, only Vallonia were found infected with protostrongylid-type larvae (10 of 980=1%). Lungworm prevalence in bighorn fecal samples was 97% on Antelope Island and 90% on the Newfoundland Mountains. Lungworm prevalence in lambs indicated lungworm transmission was occurring on Antelope Island. Lungworm transmission was likely occurring in riparian habitat due to abundant gastropods, presence of infected gastropods, and reliance by bighorn sheep on few water sources. Differences in spatial distribution between ram and nursery groups may partly explain higher fecal larvae counts in nursery than in ram groups. We suggest lungworm levels in bighorn sheep on semiarid ranges may increase in dry years as bighorn sheep concentrate use on fewer perennial water sources.
Buscar no Google
Base de dados:
MEDLINE
Assunto principal:
Doenças dos Ovinos
/
Caramujos
/
Infecções por Strongylida
/
Carneiro da Montanha
/
Metastrongyloidea
Tipo de estudo:
Prevalence_studies
/
Risk_factors_studies
Limite:
Animals
País como assunto:
America do norte
Idioma:
En
Ano de publicação:
2008
Tipo de documento:
Article