Veterinary Therapeutics最新文献

Potassium bromide, phenobarbital, or a combination of both is commonly used in the treatment of canine epilepsy. Several cases of clinical pancreatitis have been reported in dogs after treatment with potassium bromide, but the risk of elevated serum canine pancreatic lipase immunoreactivity concentrations in dogs treated with potassium bromide and/or phenobarbital has not previously been evaluated in a large group of dogs. This study suggests an increased risk for elevated serum canine pancreatic lipase immunoreactivity concentrations and possibly pancreatitis in dogs treated with potassium bromide or phenobarbital alone or in combination.

Veterinarians in Ontario and Quebec, Canada, typically prescribe monthly heartworm prophylactic and anthelmintic medications for use during the warm months of the year. In many patients, the use of dewormers is discontinued during the winter because of the perception that intestinal parasite infections and shedding of nematode eggs are unlikely when the weather is cold and the ground is frozen or covered with snow. This study examined fecal samples obtained from 96 shelter dogs and cats during the winter in Ontario and Quebec. Intestinal parasites were identified in 34% of submitted samples. These findings support the recommendation that veterinarians should advise pet owners to continue administration of broad-spectrum parasiticides to companion animals during the winter months.

Several veterinarians and dairy producers elect to vaccinate dairy herds with killed combination products in the fall or spring. Postvaccinal milk drop has been reported following the use of some killed vaccines, making it important to identify vaccines that can cause milk drop and evaluate the magnitude of postvaccinal milk drop. This study compared the pre- and postvaccinal milk production levels of dairy cows vaccinated with two commercial vaccines or injected with a saline placebo. Dairy cows receiving vaccine C (Cattlemaster Gold FP5; Pfizer Animal Health, Montreal, Canada) experienced a statistically significant difference in mean postvaccinal milk drop (-1.83 kg/cow/day) compared with cows receiving vaccine T (Triangle 4+Type 2 BVD, Wyeth Animal Health, Guelph, Ontario, Canada; -0.63 kg/cow/day) or saline (-0.02 kg/cow/day).

Three groups (n=9 or 10) of 12-week-old canine parvovirus type 2 (CPV-2) antibody-negative puppies were vaccinated: one group with a product containing modified-live CPV-2b (Galaxy DA2PPv; Schering-Plough Animal Health), one group with a product containing modified-live CPV-2 (Continuum DAP, Intervet), and one group (controls) with sterile saline. All puppies receiving CPV-2 and CPV-2b vaccines developed antibody as determined by the hemagglutination inhibition assay. All groups of puppies were challenged with a combination of virulent CPV-2b and CPV-2c 5 weeks after vaccination. All puppies in the CPV-2 and CPV-2b vaccinated groups were protected from disease, whereas all control group puppies developed disease and 50% died or were euthanized. This study demonstrated that the CPV-2 and CPV-2b vaccine components of the Continuum DAP and Galaxy DA2PPv products, respectively, provided protection against the CPV-2b virus and also provided complete protection against the new CPV-2c variant.

Four active ingredients--imidacloprid selamectin, fipronil-(S)-methoprene, and metaflumizone--were tested to assess the speed of flea kill against existing flea infestations and subsequent reinfestations. Thirty flea-infested cats were allocated to four treatment groups and one untreated control group. Flea counts were performed 6, 18, and 48 hours after treatment (day 0) and 2, 4, and 24 hours after weekly flea reinfestations. Cats were also reinfested with fleas after the 6- and 18-hour counts on day 0 and after the 2- and 4-hour counts on subsequent count days. Imidacloprid provided significantly greater flea kill at diverse time points. At the 24-hour counts, all compounds showed expected and similar high efficacies. On study day 34, imidacloprid showed the highest efficacy at 24 hours after reinfestation, with 90.8% flea reduction compared with 55.7% to 67.4% in the other treatment groups. A single topical application of imidacloprid provided a high efficacy in the early elimination of adult fleas, limiting the risk of pathogen transmission and flea allergy dermatitis.

The purpose of this study was to evaluate the relative efficacy and cost-effectiveness of feeding melengestrol acetate (MGA) to feedlot heifer calves in western Canada. Heifers fed MGA had significantly (P less than .05) improved average daily gain, feed conversion, and carcass quality grade and lower rates of initial undifferentiated fever treatment and bovine respiratory disease mortality. However, heifers fed MGA had less desirable (P less than .05) carcass yield grade. There was a net economic advantage of Can $11.31/animal in favor of heifers fed MGA. Based on these results, it is efficacious and cost-effective to feed MGA to heifer calves raised in standard large-pen commercial feedlots in western Canada.

This study was designed to compare morbidity and mortality due to bovine respiratory disease (BRD) in 1,400 ranch-fresh, northern US calves that received either no metaphylaxis (MTX) (Group 1), MTX prompted by pen morbidity (Group 2), MTX prompted by a decline in feed intake (Group 3), or on-arrival MTX (Group 4). Ceftiofur crystalline free acid (6.6 mg/kg) was the MTX antimicrobial used. Decreased feed intake did not meet the study threshold, so Groups 1 and 3 were combined into a single control group. The percentage of calves not treated for BRD was 14% to 15% higher in Groups 4 and 2 (72.7% and 73.4%, respectively) compared with the controls (58.2%; P ≤ .02). Mortality was numerically higher in Group 2 (3.4%) compared with Groups 4 and 1 (0.9% and 1.6%, respectively). There were no differences in average daily gain or feed consumption. In northern, ranch-fresh calves, MTX as a health management practice reduces the incidence of BRD and has better utility when performed on arrival versus relying on morbidity as a signal for antimicrobial administration.

The event that 8 of 12 pups born to a Lyme borreliosis-positive dam tested positive on a commonly used in-hospital Lyme borreliosis test kit at 1 week of age prompted breeder concern about the possibility and implications of transplacental Lyme borreliosis infection. Almost 2 weeks after the initial serologic test results were obtained, blood was collected from the puppies for comprehensive testing. Assessment of the findings indicate the possibility that passive transfer of maternally derived antibody to the in vivo expressed C6 peptide of Borrelia burgdorferi can temporarily render pups serologically positive for antibodies on the in-hospital C6 Lyme borreliosis antibody test kit when the test is run on very young animals.

The purpose of this study was to compare the efficacy and cost-effectiveness of florfenicol versus tulathromycin for initial treatment of undifferentiated fever in fall-placed steer calves that received metaphylactic tilmicosin on arrival at the feedlot. No significant differences (P > .10) were observed in undifferentiated fever relapses or the crude case fatality rate. Calves treated with florfenicol had a lower case fatality rate (P = .04) for bovine respiratory disease and Histophilus disease than did calves treated with tulathromycin. The net economic advantage of florfenicol over tulathromycin (Can$17.70/treated animal) was based on differences in costs for the trial drug and calf replacement owing to bovine respiratory disease and Histophilus disease case fatality.

Three studies evaluating various aspects of the performance of pyriprole against the cat flea, Ctenocephalides felis, on dogs demonstrated that 12.5% pyriprole applied as a spot-on provides rapid, long-lasting efficacy against adult cat fleas, even under severe flea challenge. Speed of kill data indicate treatment with this product can interrupt an already established adult flea infestation, whereas monthly treatment can prevent reinfestation. Pyriprole disrupts the flea life cycle by killing adult fleas before they lay eggs for at least 30 days after treatment. The residual effect of pyriprole on debris from treated dogs (dander, hair, scales, and flea feces) resulted in a decreased ability of cat flea larvae to complete development to the adult stage for 2 weeks after application. Based on the results of these studies, 12.5% pyriprole represents a valuable new tool in the control of the cat flea, C. felis, on dogs.