Vitalität und Parasitenbefall von Schafen in ganzjähriger Freiland­ haltung Summary

Title of the paper: Vigour and endoparasite incidence of outdoor sheep The aim of the present study was, to examine the influence of the husbandry system on parasite incidence of ewes and lambs, the relationship between parasite incidence and blood parameters and the association between parasite incidence and behaviour of sheep. A total of 73 ewes from 4 genetic groups (Rhonsheep, German Blackface and reciprocal crosses of the two breeds) as well as 32 female lambs from 3 genetic groups [Rhonsheep, CharmoisexGerman Blackface, Charmoisex(RhonsheepxGerman Blackface)] were included in the analysis. From April to December, the sheep of the reference group grazed on a paddock managed as rotational grazing and during winter time they were kept in a bam. The sheep of the outdoor group were kept without a barn on a paddock. In January and February, ewes of both groups lambed. During the whole trial period, no anthelmintic treatment was carried out. From June to November 2000, blood and faeces samples were taken and sheep were weighed monthly. In October 2000, behaviour of ewes and lambs was observed in an arena. The incidence of nematodes was lower in ewes with a faecal egg count (FEC) of 217 compared to their lambs which showed a FEC of 1.912. It was concluded that ewes had a higher parasite resistance. The outdoor lambs showed a significantiy higher FEC of 2.523 than the lambs of the reference group with a FEC of 1.131. The reason might be the permanent grazing of the outdoor sheep on the paddock with a cumulative parasite infection. A negative correlation of -0.21 between FEC and the eosinophile leucocyte level means that the blood parameter was an indicator of parasite incidence. There was no relationship between parasite incidence and behaviour of sheep in the arena. In future, breed differences and the association between parasite incidence and mothering ability will be