+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Comparative efficacy of ivermectin pour-on, albendazole, oxfendazole and fenbendazole against Ostertagia ostertagi inhibited larvae, other gastrointestinal nematodes and lungworm of cattle



Comparative efficacy of ivermectin pour-on, albendazole, oxfendazole and fenbendazole against Ostertagia ostertagi inhibited larvae, other gastrointestinal nematodes and lungworm of cattle



Veterinary Parasitology 73(1-2): 73-82



An experiment was conducted to evaluate the current efficacy of albendazole (ABZ), oxfendazole (OXF) and fenbendazole (FBZ) compared with ivermectin pour-on (IVM-PO) against inhibited early fourth-stage larvae (IEL4) of Ostertagia ostertagi, other gastrointestinal nematodes and lungworm of cattle during spring in Louisiana. Twenty-five crossbred beef heifer calves of 235 kg average weight and 10-12 months of age were acquired in late winter and grazed for 9 weeks on pasture contaminated with O. ostertagi and other nematodes until May 15. The cattle were weighed and randomly allotted into 5 groups of 5 calves on May 16 (day 0) and treatments were as follows: group 1, nontreated controls (CONT); group 2, IVM-PO on mid-backline at 500 micrograms/kg; group 3, ABZ suspension (oral) at 10 mg/kg; group 4, OXF suspension (oral) at 4.5 mg/kg; group 5, FBZ suspension (oral) at 5 mg/kg. After treatment and confinement in separate pens for each group, approximately equal numbers of cattle from each group were necropsied daily between days 29-31. Mean numbers of O. ostertagi developmental stages present in CONT were: adult, 5234; developing (DL4), 3130; IEL4, 44,077. The mean percentage of IEL4 was 84.1. Cooperia spp. were the second most prevalent in CONT (20,307) and smaller numbers of abomasal and intestinal species and Dictyocaulus viviparus were present in nearly all CONT. Percent reductions for the four compounds against O. ostertagi adult, DL4 and IEL4, respectively, were IVM-PO: 99.7, 98.3, 98.1; ABZ: 74.1, 76.5, 75.3; OXF: 78.5, 42.1, 32.0; FBZ: 63.6, 17.7, 39.7. Efficacy of IVM-PO was greater (P < 0.05) against all O. ostertagi stages than the benzimidazole (BZ) drugs, except for ABZ (DL4). There were no significant differences in group means (except for C. punctata adult males, P < 0.05 lower for IVM-PO) or wide variation in reduction percentages for other abomasal and intestinal species and D. viviparus between IVM-PO and BZ drugs. The low efficacy of all three BZ drugs for O. ostertagi, but especially for OXF and FBZ, under conditions of this experiment, were suggestive of drug tolerance to dosages employed or resistance. However, problems of drug availability/concentration in the abomasum, and the factor of IEL4 and DL4 replacing adult worms after treatment cannot be excluded. Efficacy of the BZ drugs against all other species were essentially similar to that of IVM-PO.

Please choose payment method:






(PDF emailed within 1 workday: $29.90)

Accession: 045583145

Download citation: RISBibTeXText

PMID: 9477494


Related references

Efficacy of albendazole, levamisole and fenbendazole against gastrointestinal nematodes of cattle, with emphasis on inhibited early fourth stage Ostertagia ostertagi larvae. Veterinary Parasitology 40(1-2): 59-71, 1991

Efficacy of abamectin against natural infections of gastrointestinal nematodes and lungworm of cattle with special emphasis on inhibited, early fourth stage larvae of Ostertagia ostertagi. Veterinary Parasitology 41(1-2): 77-84, 1992

The efficacy of thiophanate against gastrointestinal nematodes of cattle including inhibited larvae of Ostertagia ostertagi. Veterinary Record 105(19): 444-445, 1979

Efficacy of fenbendazole against inhibited larvae of Ostertagia ostertagi in yearling cattle. American Journal of Veterinary Research 45(10): 1989-1993, 1984

Efficacy of an albendazole feed formulation against bovine gastrointestinal nematodes including arrested larvae of Ostertagia ostertagi. American Journal of Veterinary Research 47(1): 119-122, 1986

Efficacy of a spring strategic fenbendazole treatment program to reduce numbers of Ostertagia ostertagi inhibited larvae in beef stocker cattle. Veterinary Parasitology 59(2): 127-137, 1995

The efficacy of injectable 10% albendazole in cattle naturally infected with various species of intestinal nematodes and L4 larvae of Ostertagia ostertagi. Revista de Medicina Veterinaria Buenos Aires 77(3): 216-219, 1996

Effects of oxfendazole, levamisole, and ivermectin treatment on removal of inhibited Ostertagia ostertagi larvae and production parameters in feedlot steers. Agri Practice 12(5): 14-15, 17-20, 1991

Efficacy of fenbendazole against inhibited larvae of Ostertagia ostertagi. Livestock producers' day report Louisiana Agricultural Experiment Station Animal Science Department4(24): 4-12, 1983

Efficacy of fenbendazole against inhibited larvae of ostertagia ostertagi. Veterinary Record 108(11): 228-230, 1981

Efficacy of oxfendazole against inhibited larvae of Ostertagia ostertagi acquired by calves in the spring. American Journal of Veterinary Research 49(7): 1007-1009, 1988

Efficacy of ivermectin delivered from a sustained-release bolus against inhibited early fourth-stage larvae of Ostertagia ostertagi and other namatodes in cattle. American journal of veterinary research 53(5): 793-795, 1992

Efficacy of oxfendazole against inhibited Ostertagia ostertagi in naturally infected cattle. Australian Veterinary Journal 55(5): 232-235, 1979

Efficacy of oxfendazole against inhibited larvae of Ostertagia ostertagi in naturally infected calves in the southern USA. Veterinary Record 124(17): 462-464, 1989

Anthelmintic efficacy of albendazole against inhibited larvae of Ostertagia ostertagi. American Journal of Veterinary Research 42(2): 318-321, 1981