Veterinary Therapeutics最新文献

The efficacy of top-dress antiinflammatory drugs ultimately depends on a patient's willingness to consume treated feed. The current study compares the palatability of two phenylbutazone top-dress formulations (Equipalazone Powder, Dechra Pharmaceuticals, and Pro-Dynam, VetXX, Ltd.) and a suxibuzone top-dress formulation (Danilon Equidos, Janssen Animal Health). Results of a three-period, crossover study on 18 healthy horses showed that Pro-Dynam was significantly less palatable, with significantly less consumption of treated feed compared with either Equipalazone Powder or Danilon Equidos. There was no statistically significant difference in terms of consumption of treated feed and palatability scores between Equipalazone Powder and Danilon Equidos.

Larger livestock units, a decline in the farm labor force, animal welfare concerns, and a trend toward more selective use of drugs have increased the focus on animal handling, time management, convenience, and compliance in administering veterinary therapeutics. This study was undertaken to quantify and compare the time needed to treat commercial beef cattle with three fluke and worm combination products with different administration profiles. Young beef cattle (n = 270) weighing approximately 400 kg were allocated to batches of five, which were randomly assigned to receive ivermectin + clorsulon injection, ivermectin + closantel injection, or levamisole + triclabendazole oral drench. The mean time needed to administer ivermectin + clorsulon (single injection) to five cattle was 31 seconds, which was significantly less than the 100 seconds needed for ivermectin + closantel (two injections) and the 126 seconds needed for levamisole + triclabendazole (P < .001). Such quantitative data can allow for better planning and selection of parasiticide treatment approaches at the farm level.

The purpose of this study was to compare the relative cost-effectiveness of florfenicol with that of tulathromycin for treatment of undifferentiated fever (UF) in feedlot calves at ultra-high risk of developing UF that receive metaphylactic tulathromycin on arrival at the feedlot. Calves that received therapeutic florfenicol had lower overall mortality (P=.045) and bovine respiratory disease mortality (P=.050) compared with calves that received therapeutic tulathromycin, but no significant differences were detected in feedlot performance, carcass characteristics, or other animal health variables. There was a net advantage of Can$41.19/treated animal in the florfenicol group versus the tulathromycin group. This study demonstrates that it is more cost-effective to use florfenicol than tulathromycin for the initial treatment of UF in feedlot calves at ultra-high risk of developing UF that receive on-arrival metaphylactic tulathromycin.

The safety of using otic formulations is often of concern for practitioners and pet owners alike, with "safe" in this context meaning no adrenocortical suppression. This study evaluated the effect of four glucocorticoid-containing otic formulations on plasma cortisol concentrations, measured by corticotropin stimulation testing (plasma cortisol concentrations before and after corticotropin injection), in dogs presented with otitis externa. Dexamethasone tended to have larger adrenocortical suppression compared with the other three formulations (betamethasone, triamcinolone, and mometasone), but the difference was not statistically significant. The largest difference among the four drugs was observed between dexamethasone and betamethasone (P=.09).

The purpose of this study was to compare the efficacy and cost-effectiveness of tilmicosin (MIC) versus tulathromycin (DRAX) as a metaphylactic antimicrobial in feedlot calves at moderate risk for bovine respiratory disease (BRD). Calves that received DRAX had significantly (P < or = .05) lower initial BRD treatment rates compared with calves that received MIC. However, there were no significant differences in the BRD relapse rate, railer rate, total mortality rate, BRD mortality rate, average daily gain, and dry matter conversion between the two groups. The economic advantage of the MIC group was Can$8.29/animal. Based on these results, while DRAX was more efficacious in reducing initial treatments for BRD in feedlot calves at moderate risk for disease, MIC was more cost-effective. The lower initial BRD treatment costs in the DRAX group did not offset the higher metaphylactic cost of DRAX.

The purpose of this study was to determine the activities of two antibacterial agents used in the treatment of bovine respiratory infections-tulathromycin, a macrolide, and ceftiofur, a third-generation cephalosporin-alone, in combination with each other, and in combination with each of seven additional antibiotics (tilmicosin, florfenicol, enrofloxacin, danofloxacin, ampicillin, tetracycline, and penicillin G) against bovine Pasteurella multocida (n = 60) and Mannheimia haemolytica (n = 10) isolates for determination of synergy, antagonism, or indifference. Of 458 organism-drug combinations, 160 combinations of tulathromycin and 209 combinations of ceftiofur with eight antimicrobial drugs were indifferent. One combination was antagonistic (ceftiofur + florfenicol against one isolate of P. multocida). Time-kill studies showed loss of cidality for ceftiofur when combined with florfenicol at 1x the minimal inhibitory concentration. Overall, the in vitro data demonstrated that tulathromycin and ceftiofur, in combination with each other or seven other antimicrobial agents, primarily produce an indifferent response with no occurrences of synergism and rare occurrences of antagonism.

This study evaluated overall efficacy, percentage of dogs free of live ticks, retention of ticks, and efficacy against retained ticks of fipronil (9.8% w/w) + (S)-methoprene (8.8% w/w) and imidacloprid (8.8% w/w) + permethrin (44% w/w) spot-on topical solutions against Dermacentor variabilis-infested dogs. Tick control was significantly greater (P < .05) on dogs treated with fipronil + (S)-methoprene than on control dogs for the entire 30-day study period. Conversely, the combination product of imidacloprid + permethrin demonstrated activity significantly (P < .05) different from that seen on control dogs only up to day 23. Significantly (P < .05) more dogs treated with fipronil + (S)-methoprene were free of live ticks compared with controls on days 3, 9, and 16. There was never a significant difference (P > .05) between control and imidacloprid + permethrin-treated dogs in numbers of dogs free of live ticks. After the initial 10-minute tick exposure, lower numbers of ticks were retained on the imidacloprid + permethrin-treated dogs than on the fipronil + (S)-methoprene-treated dogs. However, when evaluating the effectiveness of the acaricides on "retained ticks," it appears that while some of the ticks were rapidly knocked down on the imidacloprid + permethrin-treated dogs, efficacy against ticks still retained at 10 minutes was never greater than 50%.

Preliminary studies showed spinosad to be rapidly effective and safe in controlling fleas on dogs. To validate these studies, a clinical trial was undertaken using 470 flea-infested client-owned dogs allocated to receive three monthly treatments with either beef-flavored chewable spinosad tablets (30-60 mg/kg) or selamectin applied according to label instructions. Flea counts 15 days after enrollment were reduced by 98.6% and 90.9% for spinosad- and selamectin-treated dogs, respectively; at 90 days, flea count reductions were 99.9% and 98.9%, respectively. Compared with baseline, all flea reductions were significant (P < .001) for both products and spinosad was significantly (P ≤ .0172) more effective than selamectin at each postenrollment flea count.

Pancreatitis is recognized as an important and common problem in dogs, but diagnosis can be challenging. Recently, new assays for the measurement of trypsin-a1-proteinase inhibitor complexes and canine pancreatic lipase immunoreactivity (cPLI and Spec cPL) have been developed and analytically validated. This is the first report of a direct comparison of the sensitivity of these and other more traditional serum markers for the diagnosis of canine pancreatitis in a subset of dogs with this disease (i.e., dogs with both macroscopic and microscopic changes characteristic of pancreatitis). Serum cPLI and Spec cPL concentrations showed the highest sensitivity for the diagnosis of pancreatitis in this group of patients. Further studies will be required to compare the specificity of these serum markers and thus determine their overall clinical utility.

Enterotoxigenic Escherichia coli is one of the primary etiologic agents for diarrhea in neonatal calves. Immunization of dams can provide passive protection in neonatal calves; antibodies transferred through colostrum block colonization of bacteria, thereby preventing disease. In this study, healthy pregnant heifers were vaccinated at approximately 3 months of gestation with either a polyvalent oil-adjuvanted vaccine containing inactivated coronavirus, rotavirus, E. coli K99 subunit antigen, and Clostridium perfringens b and e toxoid or normal saline as a placebo. Calves were allowed to nurse immediately after birth, were orally challenged with virulent heterologous enterotoxigenic E. coli at 1 day of age, and were observed for clinical signs of scours for 10 days. Signs of severe scours were noted in 75% of control calves and 28.6% of vaccinates, and the severity of scours was significantly higher (P = .0382) in the control group. The mortality rate was significantly higher (P = .0007) in the control group (80%) than in the vaccinate group (14%). These findings indicate that the vaccination of pregnant heifers at as early as 3 months of gestation (6 months before calving) provides passive protection in neonatal calves against colibacillosis.