Prevention of parasitic gastroenteritis and parasitic bronchitis in first and second season grazing cattle
Hollanders, W.; Berghen, P.; Dorny, P.; Hilderson, H.; Vercruysse, J.; Ryan, W.G.
Veterinary Record 130(16): 355-356
1992
ISSN/ISBN: 0042-4900 PMID: 1534429 Document Number: 397111
Thirty parasite-naive Holstein-cross heifers aged 7 to 12 months were allocated into 3 groups and were treated with either an oxfendazole pulse release bolus (Repidose) administered orally at turnout or ivermectin (Ivomec) injected s.c. at 200 micro g/kg at 3, 8 and 13 weeks after turnout or untreated (control group) except for therapeutic treatments as required. They were turned out in May of the first year onto 3 adjacent plots of permanent pasture, housed from October to May and turned out in May of the second year as a single group. Larvae of Dictyocaulus viviparus were not detected on the pasture or in faecal samples from any of the groups in the first season and there was no evidence of lungworm infection. There were no signs of parasitic gastroenteritis in the treated groups in the first season but 2 severe outbreaks affected the control groups and resulted in a mean loss of 50 kg bodyweight in these animals at housing compared to the treated group. No signs of parasitic gastroenteritis were seen in any of the cattle during the second grazing season but severe parasitic bronchitis affected all the cattle in July; cattle were treated first with levamisole (L-Ripercol pour-on)and after a relapse 18 days later with ivermectin. Mean bodyweight gains fell in all the groups. It is concluded that early season anthelmintic prophylaxis prevented the long term impact of gastrointestinal parasitism in first season calves; in the second season further anthelmintic prophylaxis or vaccination may be needed to minimize the risk of parasitic bronchitis.