Persistent efficacy and production benefits following use of extended-release injectable eprinomectin in grazing beef cattle under field conditions
| Autor: | Bert E. Stromberg, Bruce N. Kunkle, S. Yoon, E. G. Johnson, Larry L. Smith, T. A. Yazwinski, J.C. Williams, L.G. Cramer |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
Male
Veterinary medicine Efficacy Nematodes Cattle Diseases Biology Beef cattle Weight Gain Injections Feces Random Allocation Acceptability Animal science Grazing medicine Extended-release injection Animals Trichostrongylus Anthelmintic Nematode Infections Parasite Egg Count Productivity Eprinomectin Oesophagostomum Ivermectin General Veterinary Antinematodal Agents General Medicine biology.organism_classification veterinary(all) Bunostomum Cattle Female Parasitology medicine.symptom Lungworm Weight gain medicine.drug |
| Zdroj: | Veterinary Parasitology. 192:332-337 |
| ISSN: | 0304-4017 |
| DOI: | 10.1016/j.vetpar.2012.11.039 |
| Popis: | Seven studies were conducted in commercial grazing operations to confirm anthelmintic efficacy, assess acceptability, and measure the productivity response of cattle to treatment with eprinomectin in an extended-release injectable formulation (ERI) when exposed to nematode infected pastures for 120 days. The studies were conducted under one protocol in the USA in seven locations (Arkansas, Idaho, Louisiana, Minnesota, Missouri, Oregon, and Wisconsin). Each study had 67–68 naturally infected animals for a total of 475 (226 female, 249 male castrate) Angus or beef-cross cattle. The animals weighed 133–335kg prior to treatment and were approximately 3–12 months of age. The studies were conducted under a randomized block design based on pre-treatment body weights to sequentially form 17 replicates of four animals each within sex in each study. Animals within a replicate were randomly assigned to treatments, one to Eprinomectin ERI vehicle (control) and three to Eprinomectin ERI (5%, w/v eprinomectin). Treatments were administered at 1mL/50kg body weight once subcutaneously anterior to the shoulder. All animals in each study grazed one pasture throughout the observation period of 120 days. Cattle were weighed and fecal samples collected pre-treatment and on 28, 56, 84, and 120 days after treatment for fecal egg and lungworm larval counts. Positive fecal samples generally were cultured en masse to determine the nematode genera attributable to the gastrointestinal helminth infection. Bunostomum, Cooperia, Haemonchus, Nematodirus, Oesophagostomum, Ostertagia, and Trichostrongylus, when present, were referred to as strongylids. At all post-treatment sampling intervals, Eprinomectin ERI-treated cattle had significantly (P |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect