No abstract

The objective of the present study was to determine the dynamics of infestation of cattle and pasture by gastrointestinal nematodes in a mild humid environment in northwestern Spain. For this, infestation of pasture by free-living stages (L3), dynamics of faecal egg output, blood pepsinogen levels and worm burden in slaughtered animals were quantified. The results showed a high degree of annual variability, which was dependent on weather conditions. The seasons were clearly defined in the study area, with mild humid winters and relatively dry summers registered throughout the years of the study. Infestation of pasture by larvae varied from year to year, peaking during August in the first year, between August and December in the second year, and during October in the third year. The annual variation was mainly due to weather conditions, particularly the amount of rain in summer. The patterns of faecal egg output were similar in the first and third grazing seasons, with maximum levels observed in May/June; however, in the second year, the peak was reached in October. Blood pepsinogen levels increased from pasture turnout (March/April) until the end of the grazing season (November/December), reaching maximum values from August/September onwards. The nematode parasite species identified at necropsy were Ostertagia osteragi, O. lyrata, Cooperia oncophora, C. macmasteri, C. punctata and Trichuris ovis, with O. ostertagi and C. oncophora predominating. In faecal cultures, the following genera were also identified: Haemonchus, Trichostrongylus, Nematodirus, Bunostomum, Oesophagostomum and Strongyloides. There was a significant correlation (r=0.97, P<0.01) between worm burden (Ostertagia spp.) and pasture infestation (Ostertagia L3) 3 weeks prior to slaughter of the calves, and also between blood pepsinogen levels and pasture infestation by Ostertagia L3 (r=0.33, P<0.02). Correlations between worm burden and faecal egg output and between blood pepsinogen level and faecal egg output were not significant. The results obtained in the present study confirm that there is annual variability in the time-course of nematodosis in cattle, and demonstrate the importance of weather, particularly summer rainfall, in an Atlantic temperate environment.

The bronchopulmonary helminths of 66 chamois (49 males and 17 females), captured in various parts of the Cantabrian moun tain range (N. W. Spain) in the autumn of 1983, and in the summer and the autumn of 1984, were studied. The animals were adult and aged between 2 and 16 years.The lungs, trachea and faeces from the last section of the intes tine were taken from each animal individually. The trachea and pulmonary larval nodules were dissected. First stage larvae (L-I) were obtained from finely cut up pulmonary tissue and from faeces by migration.The number of larvae I per gram varied between 0.08 and 2,662 (x = 151.5 ± 59.5 s. e.) in the faecal samples, and between 0.03 and 1,733 (x = 65.2 ± 32.4 s. e.) in the pulmonary ones. There was a low correlation between the two sets of data.When taking into account age and sex, no statistically signifi cant differences were observed in relation to the number of larvae/gram found either in faeces or in pulmonary tissue, while there were statistically significant differences when considering the periods of sampling and reserve of origin, in relation to the larvae found in faeces and lungs, respectively.Infections by three nematodes (Neostrongylus, Muellerius and Protostrongylus) were more common than those produced by two or one, in the lungs as well as in the faeces. The most common genus was Neostrongylus, followed by Muellerius, and no Cystocaulus or Dictyocaulus larvae were found. R ésumé : Les helminthes bronchopulmonaires des chamois (Rupicapra rupicapra parva) abattus au nord-ouest de l'Espagne : estimations selon les numérations des larves du premier stade dans les fèces et les poumons.

No abstract

No abstract