Prevalence of gastrointestinal nematodes and Fasciola hepatica in sheep in the northwest of Spain: relation to climatic conditions and/or man-made environmental modifications

Particle and Fibre Toxicology

Francisco A Rojo-Vázquez²  Luciano Castañón-Ordóñez²  Camino González-Lanza¹  Nélida Fernández-Pato²  Ma del Rosario Famularo²  Coral Cordero-Pérez²  Jose Manuel Martínez-Pérez²  David Robles-Pérez²  María Martínez-Valladares¹ 

[1]Instituto de Ganadería de Montana, CSIC-ULE, Finca de Marzanas, 24346, Grulleros León, Spain

[2]Faculty of Veterinary Medicine, University of León, Campus de Vegazana, 24071 León, Spain

关键词: Climatic conditions;    Prevalence;    Sheep;    Fasciola hepatica;    Gastrointestinal nematodes;   

Others  :  824405
DOI  :  10.1186/1756-3305-6-282

 received in 2013-03-16, accepted in 2013-09-12,  发布年份 2013

【 摘 要 】

Background

In the present study we studied and updated the prevalence of the infections caused by gastrointestinal nematodes (GIN) and Fasciola hepatica in grazing sheep in the northwest (NW) of Spain for the last six years (2006–2011), and its relationship with the current climatic conditions.

Methods

We analyzed faecal samples from 110 flocks located in four different provinces of the Autonomous Community of Castilla y León: 76.4% of them were situated in León, 12.7% in Zamora, 9.1% in Palencia and 1.8% in Valladolid.

Results

The prevalence of GIN was 100% and the mean of eggs per gram (epg) in faeces was 237.2 (± 375.9) per flock. Regarding climatic conditions, we found a direct relationship between the GIN infection level and the maximum humidity (p<0.05) but inverse with the degree of solar radiation (p<0.05). The prevalence of fasciolosis was 59.3%, with a mean epg of 17.5 (± 33.9) per flock; these values were correlated with the minimum humidity and precipitations (p<0.05). Comparing our results in León with previous studies during the early 1990s, the mean epg of GIN was increased slightly (134.3 epg); regarding fasciolosis, the prevalence rose significantly, from 26.7% to 60.5%. Since the 1990s we observed that the maximum temperature is nowadays 0.45°C higher (17.0°C) and the minimum 0.5°C lower (5.2°C); the rainfall values were very similar in both decades but at the present time the humidity is higher (75.9%).

Conclusions

We found that the prevalence of GIN and F. hepatica infections was directly influenced by the humidity and also by precipitations in the case of F. hepatica. Comparing the current prevalence with studies carried out in the same area for the early 1990s, we observed that nowadays the mean epg of GIN is higher with a possible cause being the differences in climatic conditions depending on the sampling year. Regarding F. hepatica infection, its prevalence rose significantly probably favoured by an increase in irrigated areas in the area of study.

【 授权许可】

   
2013 Martínez-Valladares et al.; licensee BioMed Central Ltd.

【 图 表 】

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