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Abstract

Objective—To identify race-start characteristics associated with catastrophic musculoskeletal (MS) injury in Thoroughbred racehorses at 2 racetracks in Florida during 1995 through 1998.

Design—Matched case-control study.

Animals—97 Thoroughbreds (case horses) that incurred a catastrophic MS injury during racing and 388 Thoroughbreds (control horses) randomly selected from noninjured participants and matched on the basis of racetrack and year.

Procedure—Incidence of MS injury was calculated for all race meets at 2 racetracks in Florida from 1995 through 1998. Race-start characteristics were compared among case and control horses, using conditional logistic regression.

Results—Overall incidence of MS injury was 1.2/1,000 race starts (97/79,416 starts). Incidence of injury was significantly higher for turf races (2.3/1,000 starts) than for dirt races (0.9/1,000 starts). Sex, number of days since last race, and racing surface were associated with risk of injury; geldings, ≥ 33 days since the last race, and turf racing surface were associated with a higher risk of injury.

Conclusions and Clinical Relevance—Incidence of injury among Thoroughbreds in Florida was associated with sex, number of days since last race, and racing surface. Days since last race may have been an indicator of previous health and lameness problems. Racing surface may have been a risk factor for MS injury because turf races tended to be more competitive than dirt races. Horses running in turf races were more likely to participate in races with a large field, handicap races, long races, and races with high purses. (J Am Vet Med Assoc 2001;218:83–86)

Full access
in Journal of the American Veterinary Medical Association

Objective

To assess the effect of oral administration of CaCl2 gel on blood mineral concentrations, parturient disorders, reproductive performance, and milk production of dairy cows with retained fetal membranes (RFM).

Design

Randomized field trial.

Animals

20 cows that calved normally and were not treated with CaCl2 gel (group 1), 20 cows with RFM that were treated with CaCl2 gel (group 2), and 20 cows with RFM that were not treated with CaCl2 gel (group 3).

Procedure

Group-2 cows were treated orally with CaCl2 gel (54 g of calcium) 24 and 48 hours after parturition.

Results

Administration of CaCl2 gel 24 and 48 hours after parturition did not have a significant effect on serum normalized calcium, total calcium, magnesium, or phosphorus concentrations or on incidence of metritis or left displacement of the abomasum, days to first insemination, pregnancy status after first insemination, or milk production.

Conclusions and Clinical Relevance

Administration of CaCl2 gel 24 and 48 hours after parturition did not have significant effect on blood mineral concentrations, parturient disorders, reproductive performance, and milk production in dairy cows with RFM. (J Am Vet Med Assoc 1999;215:72-76)

Free access
in Journal of the American Veterinary Medical Association

Objective

To compare efficacy of topical treatment with oxytetracycline solution or 1 of 4 nonantibiotic solutions among dairy cows with papillomatous digital dermatitis (PDD).

Design

Randomized field trial.

Animals

66 cows in a single herd.

Procedure

Cows were randomly assigned to be treated with oxytetracycline solution; a commercial formulation of soluble copper, peroxide compound, and a cationic agent; 5% copper sulfate solution; acidified ionized copper solution; hydrogen peroxide-peroxyacetic acid solution; or tap water. Cows were examined 14 and 30 days after initial treatment. During each examination, pain and lesion scores were recorded.

Results

On the basis of pain and lesion scores, oxytetracycline and the commercial formulation appeared equally effective for treatment of PDD and significantly more effective than 5% copper sulfate solution, acidified ionized copper solution, hydrogen peroxide-peroxyacetic acid solution, and tap water. Proportions of cows with signs of pain or visible lesions after treatment were significantly lower for cows treated with oxytetracycline or the commercial formulation than for cows in the other groups.

Clinical Implications

Oxytetracycline and a commercial formulation of soluble copper, peroxide compound, and a cationic agent appeared to be effective for treatment of PDD in dairy cows. (J Am Vet Med Assoc 1999;214:688–690)

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To compare 3 types of noxious stimuli applied to various anatomic areas of anesthetized dogs and rabbits for determination of the minimum alveolar concentration (MAC).

Animals—10 dogs and 10 rabbits.

Procedure—Dogs were anesthetized with isoflurane and halothane in a randomized order. Rabbits were anesthetized with isoflurane. The MAC was determined by skin incision on the lateral aspect of the chest; clamping of the tail, paw of the forelimb, and paw of the hind limb; and application of electrical current to the oral mucosa (dogs only), forelimb, and hind limb. The MAC was the end-tidal concentration midway between the value permitting and preventing purposeful movement in response to noxious stimuli.

Results—In dogs, mean ± SEM MAC for isoflurane was 1.27 ± 0.05% for clamping stimuli, 1.36 ± 0.04% for oral electrical stimulation, 1.35 ± 0.04% for electrical stimulation to the limbs, and 1.01 ± 0.07% for surgical incision. The MAC for halothane was 0.97 ± 0.03% for tail clamping, 0.96 ± 0.03% for clamping of the limbs, 1.04 ± 0.03% for electrical stimulation, and 0.75 ± 0.06% for surgical incision. In rabbits, MAC for isoflurane was 2.08 ± 0.02% for clamping stimuli, 2.04 ± 0.02% for electrical stimulation, and 0.90 ± 0.02% for surgical incision. The MAC for surgical incision was significantly lower than values for the other methods in both species.

Conclusions and Clinical Relevance—Use of electrical current and clamping techniques resulted in similar MAC values. Surgical incision underestimated MAC values in dogs and rabbits. (Am J Vet Res 2003;64:957–962)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To assess awareness, perceived relevance, and acceptance of surveillance and infection control practices at a large animal referral hospital among referring veterinarians and clients who sent horses to the facility for veterinary care.

Design—Survey.

Sample—57 referring veterinarians and 594 clients.

Procedures—A 15-question survey targeting Salmonella enterica as an important pathogen of interest in horses was sent to clients who sent ≥ 1 horse to the University of Florida Large Animal Hospital for veterinary care during July 1, 2007, through July 1, 2011, and to veterinarians who had referred horses to the same hospital prior to July 1, 2011. Responses were summarized with descriptive statistics. The χ2 test and the Wilcoxon rank sum test were used to examine associations among variables of interest.

Results—Survey response rates were low (57/467 [12%] for veterinarians and 594/3,095 [19%] for clients). Significantly more (35/56 [63%]) veterinarians than clients (227/585 [39%]) were aware that the hospital operates a surveillance and infection control program. Most veterinarians (56/57 [98%]) and clients (554/574 [97%]) indicated that sampling and testing of horses to detect Salmonella shedding in feces at admission and during hospitalization was justified. In addition, on a scale of 1 (not important) to 10 (very important), veterinarians and clients indicated it was very important (median score, 10 [interquartile range, 8 to 10] for both groups) that a referral hospital operates a surveillance and infection control program.

Conclusions and Clinical Relevance—Survey results indicated that awareness of hospital surveillance and infection control practices was higher among veterinarians than clients, and these practices were considered relevant and well-accepted among participant veterinarians and clients.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To estimate prevalence of and identify factors associated with anhidrosis in horses in Florida.

Design—Cross-sectional study and case-control study.

Animals—4,620 horses on 500 farms.

Procedures—A questionnaire was structured and mailed to farm owners or managers to obtain information related to diagnosis of anhidrosis in horses and exposure factors associated with this condition. The frequency of investigated farm- and animal-level factors was compared between farms and horses affected and not affected with anhidrosis, respectively.

Results—The prevalence of anhidrosis was 11% at the farm level and 2% at the animal level. The odds of anhidrosis were 2.13 and 4.40 times as high in farms located in central and southern Florida, respectively, compared with odds for farms in northern Florida. The odds of anhidrosis were 5.26 and 15.40 times as high in show and riding instruction operations, respectively, compared with odds for ranch operations. At the animal level, breed (Thoroughbreds and warmblood horses), foaling place (western or midwestern region of the United States), and family history of anhidrosis were significantly associated with anhidrosis.

Conclusions and Clinical Relevance—This study provides new information on the prevalence of and factors for anhidrosis in horses in Florida. Horses with a family history of anhidrosis should be examined by a veterinarian for diagnosis of this condition before they are exposed to exercise in a hot and humid climate.

Full access
in Journal of the American Veterinary Medical Association

Objective

To implement a disease monitoring system in federal, municipal, and private abattoirs in Baja California, Mexico and to estimate annual prevalence of tuberculosis (TB) in beef and dairy cattle slaughtered and inspected in 1995 and 1996.

Design

Epidemiologic survey.

Animals

About 200,000 cattle (95% beef, 5% dairy).

Procedures

Lymph node and tissue specimens with lesions suggestive of TB were fixed in neutral-buffered 10% formalin and embedded in paraffin. Sections were stained with H&E and Ziehl-Neelsen and examined for typical tuberculous lesions and acid-fast bacilli. Annual prevalence and 95% confidence intervals were estimated.

Results

Prevalence of TB in all slaughtered cattle was 0.12 and 0.46% in 1995 and 1996, respectively (beef cattle, 0.02 and 0.05%, respectively; dairy cattle, 2.0 and 8.3%, respectively). Tuberculosis cases/1,000 slaughtered cattle were linearly associated with monthly volumes of tissue submissions.

Clinical Implications

It is critical to quantify the monitoring activity at abattoirs to better estimate the prevalence of TB in slaughtered cattle. Annual prevalence of TB was significantly greater in dairy cattle than in beef cattle. Veterinarians and cattle producers in this region are encouraged to develop and work on herd plans aimed at controlling and eradicating TB. (J Am Vet Med Assoc 1997;211:709–711)

Free access
in Journal of the American Veterinary Medical Association

Summary

An elisa was compared with the plaque-reduction serum neutralization (prsn) test, for detection of vesicular stomatitis virus (vsv) antibodies in cattle in a vesicular stomatitis enzootic region of Mexico. A total of 325 bovine serum samples were screened for vsv antibodies. The prsn test was performed, using Vero cells. The elisa contained gradient-purified vsv Indiana (Lab strain) and vsv New Jersey (Hazelhurst) as the antigens. Regression analysis and weighted kappa statistic were used to estimate measures of agreement between the 2 assays for detection of vsv antibodies. The elisa method proved useful for sero-diagnosis of vesicular stomatitis The elisa and prsn test results were highly correlated for detection of vsv antibodies.

Free access
in American Journal of Veterinary Research

Abstract

OBJECTIVE To compare pursestring, Witzel (seromuscular inversion), and seromuscular incision jejunostomy tube placement techniques in vitro.

SAMPLE Jejunal specimens from 10 dogs.

PROCEDURES Jejunal segments (50 cm) were harvested immediately prior to euthanasia from 10 mixed-breed dogs Specimens were harvested with the orad and aborad ends clamped and stored in saline (0.9% NaCl) solution–soaked towels during instrumentation. Three jejunostomy tubes were placed via 3 techniques (pursestring, Witzel, and seromuscular incision), and 2 double lumen central venous catheters were placed at each intestinal end for luminal filling and leak testing. Intestinal luminal area was measured ultrasonographically with specimens suspended in a warm undyed saline solution bath with the intestinal lumen filled with dyed saline solution (intraluminal pressure, 6 mm Hg). Leak testing was performed by means of infusion of dyed saline solution (4 mL/min) until each jejunostomy site failed. Intestinal luminal area and leakage pressure were compared between the 3 tube placement techniques.

RESULTS The Witzel and seromuscular incision techniques decreased the intestinal luminal area measured at the tube insertion site, albeit nonsignificantly. For the seromuscular incision technique, a significant decrease in intestinal luminal area at the intraluminal site of measurement was found. For 2/30 specimens (1/10 pursestring and 1/10 seromuscular incision), failure occurred at pressures within the range of previously reported peak peristaltic pressure for dogs. Failure occurred at supraphysiologic peristaltic pressures for the remaining 28 specimens, including all 10 specimens for the Witzel technique.

CONCLUSIONS AND CLINICAL RELEVANCE In this in vitro study, all specimens for the Witzel technique withstood physiologic peristaltic pressures during leak testing. Both tunneling techniques (Witzel and seromuscular incision) created a decrease in intestinal luminal area. Further investigation, including in vivo testing, is indicated to evaluate the clinical relevance of these findings.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To estimate the seroprevalence of antibodies against H3N8 canine influenza virus (CIV) in a population of US dogs with influenza-like illness (ILI) and to identify factors associated with seropositivity.

Design—Cross-sectional study.

Animals—1,268 pet and shelter dogs with ILI in 42 states.

Procedures—Serum samples collected from dogs from 2005 through June 2009 were tested for H3N8 CIV antibodies with a hemagglutination inhibition assay. Intrinsic factors (age, breed, and sex), extrinsic factors (dogs housed in a shelter facility, boarding kennel, or other setting), and geographic region (southwest, west, Midwest, southeast, and northeast) were compared between seropositive and seronegative dogs to identify variables associated with seropositivity.

Results—Most (750/1,268 [59%]) dogs in the study were from Colorado, Florida, or New York. The overall seroprevalence of antibodies against H3N8 CIV was 49% (618/1,268 dogs; 95% confidence interval, 46% to 51%). The annual prevalence of H3N8 CIV seropositivity increased from 2005 (44%) to 2006 (53%) and 2007 (62%), then decreased in 2008 (38%) and 2009 (15%). The likelihood of H3N8 CIV seropositivity was associated with geographic region (southeast during 2005, west and northeast during 2006 and 2007, and northeast during 2008) and exposure setting (dogs housed in a shelter facility or boarding kennel during 2005 and 2006).

Conclusions and Clinical Relevance—Results of this study suggested there is a need for continued surveillance for H3N8 CIV infection in dogs in the United States and that personnel in communal dog-housing facilities should formulate, implement, and evaluate biosecurity protocols to reduce the risk of CIV transmission among dogs.

Full access
in Journal of the American Veterinary Medical Association