Íslenskar landbúnaðarrannsóknir - 01.09.1974, Page 17

SHEEP PARASITES IN ICELAND 15
Fig. 13. Effect of thiabendazole on the number of eggs of „other strongyles" in faeces of sheep
-(Group VII, VIII and IX). All sheep had been treated with thiabendazole in December the year
before.
lambs anthelmintica early in the summer,
just before the sheep are driven to the moun-
tain pastures or late in the summer when the
lambs return to the farms, about 2—3 weeks
before the slaughter in order to increase the
carcass weight of the lambs.
The lambs intended for breeding (about
15% of the stock) are selected before slaugh-
tering time (mid-September). These lambs
should perhaps be treated with anthelmintica
at that time in order to rid them of the
worm burden they already have acquired.
This could also diminish contamination of
the pastures near the farm with Nematodirus
eggs since these lambs are mainly responsible
for this contamination (Fig. 6 and 7).