ANUALPEC () ‘Anuário da Pecuária Brasileira.’ 1st edn. (Instituto FNP and Agra Pesquisas Ltda: São Paulo, Brazil). ANUALPEC () ‘Anuário da. million animals were finished in feedlots (BEEFPOINT, ), which represented .. the past two decades (ANUALPEC, ). Concomitantly with the greater. accounting for about % of the national herd (ANUALPEC. ), this region shows the highest growth rate in the coun- try. Crossbreeding is.
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This study aimed to evaluate the resistance status of gastrointestinal nematodes from naturally infected beef cattle to several commercially available anthelmintics, as well as to test the efficacy of combinations of anthelmintics against multi-resistant gastrointestinal nematodes. Persistent efficacy of 3. In general, the same genera identified as resistant to single drugs were found to be resistant to two-drug combinations.
Despite anialpec presence of resistant populations of Cooperia spp.
The number of animals in each experimental group ranged from 7 to 10 depending on the available calves at each farm. Many of the tested combinations were not effective, probably because of the presence of genotypes of gastrointestinal nematodes resistant to both drugs used in the combinations.
Fenbendazole was the most effective compound in the studied herds, followed by levamisole, disophenol, and moxidectin. After incubation, larvae were recovered by baermanization, after which third-stage larvae in each culture were identified by genera following the criteria described by Van Abualpec and Mayhew Each of the ten groups was randomly treated with a single drug in the first part of this study.
The results of this study showed the presence of gastrointestinal nematodes resistant to the main commercially available anthelmintic drugs on cattle farms evaluated in the state of Analpec Grande do Sul, Brazil. As an exception, ivermectin is well recognized and the most widely used anthelmintic, followed by other avermectins, benzimidazoles, levamisole, and cydectin.
Commercial availability, endectocide action, and price are generally considered most important criteria influencing the choice of drugs by farmers. Anthelmintic resistance to ivermectin and moxidectin in gastrointestinal nematodes of cattle in Europe. Closantel was effective against Haemonchus spp. First, all calves available at each farm were included in the study; however, animals with fewer than EPG before treatment were excluded prior to the formation of the experimental groups.
Therefore, previous knowledge regarding parasite resistance was used as a tool to inform the choice of potentially efficacious combinations of anuxlpec. Calves were weaned approximately six months after birth and kept in the same grazing area before and during the study on each farm.
Resistance of Cooperia spp. Ten farms located in Rio Grande do Sul state were selected by: However, in the present study, with the exception of Oesophagostomum spp. Treatment naualpec the animals with avermectin compounds did not result in satisfactory EPG reduction in any herd. Drug resistance in human helminths: The low efficacy anualoec each single drug and the presence of multi-drug resistant gastrointestinal nematodes infecting cattle are major problems that prevent adequate anthelmintic control at the farms evaluated in this study.
The resistance of Cooperia spp. In Brazil, anthelmintics are generally used at farmers’ discretion, with no restrictions to access to commercially available drugs and without any assistance from veterinarians. In critical situations of parasite resistance, in which no options of effective drugs are commercially available, combinations of two anthelmintic compounds with different mechanisms of action and unsatisfying efficacy as single drugs can xnualpec control multi-drug-resistant gastrointestinal nematodes.
Frequent use of BZs at the studied farms may have resulted in the establishment of benzimidazole-resistant parasite populations.
The use of combinations of two anthelmintic compounds with good efficacy as single drugs could be an effective means of delaying the development of drug resistance in parasites.
However, such combinations should be evaluated under the particular conditions unique to each farm. These anualpeec were distributed into 10 groups of 7—10 animals per farm and treated with ivermectin, doramectin, eprinomectin, fenbendazole, closantel, nitroxynil, disophenol, levamisole, albendazole, or moxidectin. Phenolic-substituted compounds disophenol and nitroxynil showed differing efficacy.