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61.
Comparative efficacy of tulathromycin, tilmicosin, and florfenicol in the treatment of bovine respiratory disease in stocker cattle 总被引:3,自引:0,他引:3
Nutsch RG Skogerboe TL Rooney KA Weigel DJ Gajewski K Lechtenberg KF 《Veterinary therapeutics : research in applied veterinary medicine》2005,6(2):167-179
The therapeutic efficacy and field safety of tulathromycin were evaluated in stocker calves with undifferentiated bovine respiratory disease (BRD) in three field studies conducted over two consecutive grazing seasons in Nebraska. Eight hundred calves exhibiting clinical signs of BRD and with rectal temperatures of 104 degrees F or higher were treated with tulathromycin (n = 340), florfenicol (n = 240), or tilmicosin (n = 220) and evaluated for approximately 60 days. Florfenicol and tilmicosin were administered as single SC injections according to labeled dosage. Tulathromycin was administered as a single SC injection of 2.5 mg/kg. In all three studies, the cure rate of calves 60 days after treatment with tulathromycin was significantly higher (P < or = .05) than that of calves treated with florfenicol or tilmicosin. Suspected adverse reactions were not reported for any of the study drugs. Tulathromycin proved to be significantly more effective than either florfenicol or tilmicosin in the treatment of BRD in stocker calves. 相似文献
62.
Whiting TL Salmon RH Wruck GC 《The Canadian veterinary journal. La revue veterinaire canadienne》2005,46(4):320-324
Nine of 45 horses subjected to prolonged malnutrition died subsequent to being placed with a responsible caregiver and being provided an appropriate diet. Initial extreme poor body condition score tended to be associated with death, although individual response to refeeding varied. The financial costs of stabilizing the group of horses significantly exceeded their free market price. Responsible management of chronically starved commercial animals should include options for immediate euthanasia. 相似文献
63.
Whiting TL 《The Canadian veterinary journal. La revue veterinaire canadienne》2005,46(11):1042-1046
"Brand" means a permanent identification mark of which the letters, numbers and figures used are each three (3) inches or more in length or diameter and are humanely burned into the hide of a live animal with a hot iron or tattoo or caustic chemical substance and is to be considered in relation to its location on the animal and the term relates to both the mark and location. 相似文献
64.
TerHune TN Skogerboe TL Shostrom VK Weigel DJ 《American journal of veterinary research》2005,66(2):342-349
OBJECTIVE: To compare concentrations of danofloxacin, enrofloxacin, and ciprofloxacin in plasma and respiratory tissues of calves treated after challenge with Mannheimia haemolytica. ANIMALS: 75 calves. PROCEDURE: 24 hours after challenge with M. haemolytica, 72 calves with clinical signs of respiratory tract disease were randomly assigned to 1 of 12 equal treatment groups.Three nonchallenged, nontreated calves formed a control group. Challenged calves were treated with danofloxacin (6 and 8 mg/kg, SC) and enrofloxacin (8 mg/kg, SC) once. At 1, 2, 6, and 12 hours after treatment, 6 calves from each treatment group were euthanatized. Antimicrobial drug concentrations were assayed in various specimens. Peak plasma concentration (Cmax)-to-minimum inhibitory concentration (MIC; Cmax-to-MIC) ratios and the area under the concentration versus time curve over a 12-hour period-to-MIC ratios (AUC(12h)-to-MIC) were calculat-ed. RESULTS: Danofloxacin and enrofloxacin had MICs of 0.03 microg/mL for the M. haemolytica challenge isolate. Danofloxacin administered at doses of 6 and 8 mg/kg resulted in numerically higher geometric mean concentrations of danofloxacin in plasma and all respiratory tissues than geometric mean concentrations of enrofloxacin after treatment with enrofloxacin. Geometric mean concentrations of enrofloxacin were numerically higher than geometric mean concentrations of ciprofloxacin metabolite in plasma and almost all respiratory tissues. Danofloxacin and enrofloxacin achieved Cmax-to-MIC ratios >10 and AUC(12h)-to-MIC ratios >125 hours. CONCLUSIONS AND CLINICAL RELEVANCE: When used to treat pneumonic pasteurellosis in calves, danofloxacin and enrofloxacin can be expected to deliver concentration-dependent bactericidal activity against M. haemolytica, the bacteria most commonly associated with bovine respiratory tract disease. 相似文献
65.
The metabolism of the insecticide SD 8280 [2-chloro-1-(2,4-dichlorophenyl)vinyl dimethyl phosphate] in rice plants has been examined. When rice seedlings were treated with [14C]-SD 8280 the major metabolite was 1-(2,4-dichlorophenyl)ethanol which was present mainly conjugated with plant carbohydrates. This compound was also the major metabolite present in grain and straw from rice treated with [14C]-SD 8280 and grown to maturity under paddy conditions both in the glasshouse and in an outdoor enclosure. Other metabolites detected in the mature plants included 2-chloro-1-(2,4-dichlorophenyl)vinyl methyl hydrogen phosphate and 2,4-dichloro-benzoic acid, both of which occurred in free and conjugated forms. Paddy water was sampled at intervals after the application of [14C]-SD 8280 and the total residue in the water fell from initial levels of 0.28–1.1 μg/ml (expressed as SD 8280 equivalent) immediately after treatment to <0.01 μg/ml after 2–3 weeks. The total residues in the soil from these experiments were low and did not exceed 0.20 mg/kg (SD 8280 equivalents) through the 0–15 cm profile. 相似文献
66.
Tavornpanich S Gardner IA Anderson RJ Shin S Whitlock RH Fyock T Adaska JM Walker RL Hietala SK 《American journal of veterinary research》2004,65(8):1061-1070
OBJECTIVE: To evaluate sensitivity of microbial culture of pooled fecal samples for detection of Mycobacterium avium subsp paratuberculosis (MAP) in large dairy herds and assess the use of the method for estimation of MAP prevalence. ANIMALS: 1,740 lactating cows from 29 dairy herds in California. PROCEDURE: Serum from each cow was tested by use of a commercial ELISA kit. Individual fecal samples were cultured and used to create pooled fecal samples (10 randomly selected fecal samples/pool; 6 pooled samples/herd). Sensitivity of MAP detection was compared between Herrold's egg yolk (HEY) agar and a new liquid culture method. Bayesian methods were used to estimate true prevalence of MAP-infected cows and herd sensitivity. RESULTS: Estimated sensitivity for pooled fecal samples among all herds was 0.69 (25 culture-positive pools/36 pools that were MAP positive). Sensitivity increased as the number of culture-positive samples in a pool increased. The HEY agar method detected more infected cows than the liquid culture method but had lower sensitivity for pooled fecal samples. Prevalence of MAP-infected cows was estimated to be 4% (95% probability interval, 2% to 6%) on the basis of culture of pooled fecal samples. Herd-level sensitivity estimate ranged from 90% to 100% and was dependent on prevalence in the population and the sensitivity for culture of pooled fecal samples. CONCLUSIONS AND CLINICAL RELEVANCE: Use of pooled fecal samples from 10 cows was a cost-effective tool for herd screening and may provide a good estimate of the percentage of MAP-infected cows in dairy herds with a low prevalence of MAP. 相似文献
67.
68.
Suter SE Gouthro TA McSweeney PA Nash RA Haskins ME Felsburg PJ Henthorn PS 《Veterinary immunology and immunopathology》2004,101(1-2):31-47
Historically, the dog has been a valuable model for bone marrow transplantation studies, with many of the advances achieved in the dog being directly transferable to human clinical bone marrow transplantation protocols. In addition, dogs are also a source of many well-characterized homologues of human genetic diseases, making them an ideal large animal model in which to evaluate gene therapy protocols. It is generally accepted that progenitor cells for many human hematopoietic cell lineages reside in the CD34+ fraction of cells from bone marrow, cord blood, or peripheral blood. In addition, CD34+ cells are the current targets for human gene therapy of diseases involving the hematopoietic system. In this study, we have isolated and characterized highly enriched populations of canine CD34+ cells isolated from dogs 1 week to 3 months of age. Bone marrow isolated from 2- to 3-week-old dogs contained up to 18% CD34+ cells and this high percentage dropped sharply with age. In in vitro 6-day liquid suspension cultures, CD34+ cells harvested from 3-week-old dogs expanded almost two times more than those from 3-month-old dogs and the cells from younger dogs were also more responsive to human Flt-3 ligand (Flt3L). In culture, the percent and number of CD34+ cells from both ages of dogs dropped sharply between 2 and 4 days, although the number of CD34+ cells at day 6 of culture was higher for cells harvested from the younger dogs. CD34+ cells harvested from both ages of dogs had similar enrichment and depletion values in CFU-GM methylcellulose assays. Canine CD34+/Rho123lo cells expressed c-kit mRNA while the CD34+/Rhohi cells did not. When transplanted to a sub-lethally irradiated recipient, CD34+ cells from 1- to 3-week-old dogs gave rise to both myeloid and lymphoid lineages in the periphery. This study demonstrates that canine CD34+ bone marrow cells have similar in vitro and in vivo characteristics as human CD34+ cells. In addition, ontogeny-related functional differences reported for human CD34+ cells appear to exist in the dog as well, suggesting pediatric CD34+ cells may be better targets for gene transfer than adult bone marrow. The demonstration of similarities between canine and human CD34+ cells enhances the dog as a large, preclinical model to evaluate strategies for improving bone marrow transplantation protocols, for gene therapy protocols that target CD34+ cells, and to study the engraftment potential of various cell populations that may contain hematopoietic progenitor cell activity. 相似文献
69.
Thompson LA Grieshaber TL Glickman L Glickman N 《Veterinary therapeutics : research in applied veterinary medicine》2004,5(1):75-81
The oral use of human recombinant interferonalpha-2b at 1,000 IU/ml/day appeared to provide only a transient benefit as compared with placebo for management of idiopathic recurrent superficial pyoderma in dogs. Further investigation using a larger population of dogs is needed to determine whether interferon is effective for long-term treatment of this condition. 相似文献
70.