Search Results

Abstract

Objective—To evaluate fecal concentrations of selected genera of colonic bacteria in healthy dogs, and to investigate effects of dietary fructooligosaccharides (FOS) on those bacterial populations.

Animals—6 healthy adult Beagles.

Procedure—Dogs were randomly assigned to 2 groups of 3 and fed an unsupplemented diet for 370 days. After 88 days, fecal samples were collected. Another fecal sample was collected from each dog 282 days later. Group A then received a diet supplemented with FOS, and group B continued to receive the unsupplemented diet. Twenty-eight to 29 days later, fecal samples were collected. Diets were switched between groups, and fecal samples were collected 31 and 87 days later. Concentrations of Bifidobacterium spp, Lactobacillus spp, Clostridium spp, Bacteroides spp, and Escherichia coli in freshly collected feces were determined. Effects of diet and time on bacterial concentrations were compared between groups.

Results—Bifidobacterium spp and Lactobacillus spp were inconsistently isolated from feces of dogs fed either diet. Sequence of diet significantly affected number of Bacteroides spp subsequently isolated from feces, but diet had no effect on numbers of Clostridium spp or E coli.

Conclusions and Clinical Relevance—Some genera of bacteria (eg, Bifidobacterium) believed to be common components of colonic microflora may be only sporadically isolated from feces of healthy dogs. This deviation from expected fecal flora may have implications for the effectiveness of supplementing diets with prebiotics. (Am J Vet Res 2000;61: 820–825)

Abstract

Objective—To ascertain the frequency of ultrasonographic identification of liver at sites recommended for blind percutaneous liver biopsy in middle-aged horses and to determine whether the liver is obscured by other organs or too thin for safe sample collection at recommended locations.

Design—Prospective case series.

Animals—36 healthy middle-aged (between 6 and 18 years old) Quarter Horses or Quarter Horse crosses.

Procedures—Blood samples were collected from each horse and submitted for evaluation of liver function. Horses with any indication of liver dysfunction on serum biochemical analysis were excluded. The region just below a line drawn between the dorsal aspect of the tuber coxae and the point of the elbow joint in the right 11th, 12th, 13th, and 14th intercostal spaces (ICSs) was imaged by ultrasonography for the presence of liver. In each ICS, liver thickness and whether there was partial obstruction in viewing the liver caused by other abdominal or thoracic organs were recorded.

Results—39% (14/36) of horses had liver imaged on ultrasonographic examination in all of the 11th to 14th ICSs. None of the 36 horses had liver of adequate thickness (ie, liver thickness ≥ 3.5 cm) for biopsy in all of the imaged ICSs. For 22 horses in which the liver was not visible on ultrasonographic examination of an ICS, lung was imaged instead in 12 (55%) horses, intestine in 8 (36%), and both intestine and lung in 2 (9%).

Conclusions and Clinical Relevance—On the basis of the results of this study, the practice of blind percutaneous liver biopsy in horses is not recommended because of the risk of serious complications.

Abstract

Objective—To determine the effect of azithromycin chemoprophylaxis on the cumulative incidence of pneumonia caused by Rhodococcus equi, age at onset of pneumonia, and minimum inhibitory concentration (MIC) of azithromycin for R equi isolates cultured from fecal and clinical samples.

Design—Controlled, randomized clinical trial.

Animals—338 foals born and raised at 10 equine breeding farms; each farm had a history of endemic R equi infections.

Procedures—Group 1 foals were control foals, and group 2 foals were treated with azithromycin (10 mg/kg [4.5 mg/lb], PO, q 48 h) during the first 2 weeks after birth. Foals were monitored for development of pneumonia attributable to R equi infection and for adverse effects of azithromycin. Isolates of R equi were tested for susceptibility to azithromycin.

Results—The proportion of R equi–affected foals was significantly higher for control foals (20.8%) than for azithromycin-treated foals (5.3%). Adverse effects of azithromycin treatment were not detected, and there were no significant differences between groups for the MICs of azithromycin for R equi isolates cultured from fecal or clinical samples.

Conclusions and Clinical Relevance—Azithromycin chemoprophylaxis effectively reduced the cumulative incidence of pneumonia attributable to R equi among foals at breeding farms with endemic R equi infections. There was no evidence of resistance to azithromycin. Nonetheless, caution must be used because it is possible that resistance could develop with widespread use of azithromycin as a preventative treatment. Further investigation is needed before azithromycin chemoprophylaxis can be recommended for control of R equi infections.

Abstract

Objective—To determine sex, breed, and age distributions in a population of horses with cervical vertebral compressive myelopathy (CVCM), compared with contemporaneous control horses.

Design—Retrospective case-control study.

Animals—811 horses with CVCM and 805 control horses.

Procedures—The Veterinary Medical Database was searched to identify horses with CVCM and contemporaneous control horses registered between July 1974 and August 2007. Admission date, admitting institution, sex, breed, age at the time of registration in the database, weight, and discharge status (alive, died, or euthanized) were recorded for each case and control horse.

Results—On the basis of results of multivariable logistic regression analysis, geldings and sexually intact males had a significantly higher likelihood of having CVCM than females (odds ratio [OR], 2.0 [95% confidence interval, 1.5 to 2.6]; and OR, 2.4 [95% confidence interval, 1.8 to 3.2], respectively). Thoroughbreds, Tennessee Walking Horses, and Warm-bloods were overrepresented in the CVCM group, compared with Quarter Horses. Horses that ranged from < 6 months to < 7 years of age had significantly higher odds of having CVCM, compared with horses ≥ 10 years of age.

Conclusions and Clinical Relevance—Sex, breed, and age predilections were detected in horses with CVCM. Improved understanding of these factors will aid clinical recognition of the disease in groups that may have a high prevalence of CVCM or were previously not recognized to be commonly affected. The results may also stimulate future investigations to further delineate etiopathogenesis, such as breed-related genetic causality.

Abstract

Objective—To describe frequency, types, and clinical outcomes of extrapulmonary disorders (EPDs) in foals in which Rhodococcus equi infection was diagnosed, and to identify factors determined at the time of admission that differentiated foals that developed EPDs from foals with R equi infection identified only in the lungs.

Design—Retrospective case series.

Animals—150 foals aged 3 weeks to 6 months with a diagnosis of R equi infection.

Procedures—Medical records were reviewed for information on date of admission, signalment, history, clinical signs, diagnostic testing, treatment, duration of hospitalization, invoice, and outcome. For each EPD identified, further information was collected on the identification, location, treatment, and outcome of the lesion.

Results—Of 150 foals with R equi infections, 111 (74%) had at least 1 of 39 EPDs. Survival was significantly higher among foals without EPDs (32/39 [82%]) than among foals with EPDs (48/111 [43%]), but many EPDs were only recognized after death. Risk factors significantly associated with EPDs included referral status, duration of clinical signs prior to admission, leukocytosis, and neutrophilia. Foals with EPDs also had a higher heart rate and BUN concentration than foals without.

Conclusions and Clinical Relevance—Practitioners should recognize that extrapulmonary manifestations of R equi occur with high prevalence affecting diverse organ systems, that multiple systems are generally affected when EPDs occur, and that suspicion of R equi infection should prompt evaluation and monitoring of extrapulmonary sites. Improved recognition of the presence of these disorders will help practitioners to better advise their clients in the treatment and outcome of foals with R equi infections.

Abstract

Objective—To determine whether foal management practices, environmental management, and preventative health practices are risk factors for development of Rhodococcus equi pneumonia in foals.

Design—Prospective matched case-control study.

Animals—2,764 foals on 64 equine breeding farms with 9,991 horses.

Procedure—During 1997, participating veterinarians completed paired data collection forms for comparison; 1 for an affected farm (containing ≥ 1 foal with pneumonia caused by R equi)and 1 for a control farm. Information collected pertained to stabling facilities, environmental management, foal husbandry, and preventative equine health practices.

Results—Matched farm data compared by use of conditional logistic regression indicated that personnel on affected farms were more likely to attend foal births, test foals for adequacy of passive immunity, administer plasma or other treatments to foals to supplement serum immunoglobulin concentrations, administer hyperimmune plasma prophylactically to foals, vaccinate mares and foals against Streptococcus equi infection, and use multiple anthelmintics in deworming programs. Affected farms were also more likely to have foals that developed other respiratory tract disorders and were approximately 4 times as likely to have dirt floors in stalls used for housing foals as were control farms.

Conclusions and Clinical Relevance—Rhodococcus equi pneumonia does not appear to be associated with poor farm management or a lack of attention to preventative health practices. Housing foals in stalls with dirt floors may increase the risk for development of R equi pneumonia. (J Am Vet Med Assoc 2003; 222:476–485)

Abstract

Objective—To identify risk factors for enterolithiasis in horses.

Design—Matched case-control study.

Animals—26 horses with enteroliths, 104 horses with other causes of colic that underwent surgery (52 horses, surgical control group) or were treated medically (52 horses, nonsurgical control group).

Procedure—Medical records were reviewed for horses with enteroliths and control horses. Information collected included signalment, anamnesis, and findings on physical examination and clinicopathologic testing at admission. Horses with enteroliths and control horses were compared by means of conditional logistic regression to identify factors associated with enterolithiasis.

Results—Horses that were fed alfalfa hay, spent ≤ 50% of time outdoors, or were Arabian or miniature breeds had an increased risk of developing enteroliths. Horses with enteroliths were more likely to have been hyperbilirubinemic and to have had clinical signs > 12 hours prior to admission.

Conclusions and Clinical Relevance—Breed and diet appear to influence the risk of enterolithiasis; other management factors also may influence development of enteroliths. Duration of clinical signs may be longer and signs may be less severe among horses with enteroliths, compared with horses with other causes of colic. (J Am Vet Med Assoc 2000;216:1787–1794)

Abstract

Objective—To identify farm characteristics as risk factors for the development of Rhodococcus equi pneumonia in foals.

Design—Prospective matched case-control study.

Animals—2,764 foals on 64 equine breeding farms with 9,991 horses.

Procedure—During 1997, participating veterinarians completed paired data collection forms, 1 for a farm with ≥ 1 foal with R equi pneumonia and 1 for an unaffected control farm. Matched data were compared by use of conditional logistic regression analysis.

Results—Farm characteristics found in bivariate analyses to be associated with increased risk for pneumonia caused by R equi in foals included > 200 farm acres, ≥ 60 acres used in the husbandry of horses, > 160 horses, ≥ 10 mares housed permanently on the farm (resident mares), > 17 foals, > 0.25 foals/acre, and the presence of transient mares (mares brought temporarily to the farm for breeding or foaling) and their foals. Affected farms were significantly more likely to be > 200 acres in size and have ≥ 10 resident dam-foal pairs, whereas control farms were significantly more likely to have ≥ 75% of their dam-foal pairs housed permanently on the farm.

Conclusions and Clinical Relevance—Breeding farms with large acreage, a large number of mares and foals, high foal density, and a population of transient mares and foals are at high risk for foals developing pneumonia caused by R equi. (J Am Vet Med Assoc 2003;222:467–475)

Abstract

Objective—To assess signalment, history, results of clinical and laboratory testing, and outcome for beef cattle with a left displaced abomasum (LDA), right displaced abomasum (RDA), or abomasal volvulus (AV).

Design—Retrospective study.

Animals—19 beef cattle with an AV, LDA, or RDA.

Procedure—Signalment; history; results of physical examination, diagnostic testing, and surgical exploration; and condition of the animal at discharge were obtained from medical records.

Results—Fourteen cattle had an AV, 4 had an RDA, and 1 had an LDA. Duration of clinical signs ranged from 1 to 21 days. Eighteen cattle had an AV or RDA; 7 were Brahmans, 12 were males, and median age was 10 months. Abdominal distention was observed in 11 cattle, heart rate of ≥ 100 beats/minute was detected in 14, and the abomasum was palpable per rectum in all cattle in which per rectal examination was performed. Leukocytosis, neutrophilia, hyperglycemia, azotemia, hypochloremia, and hypokalemia were common laboratory findings. At surgery, 3 cattle with an AV or RDA had a ruptured abomasum. Of the remaining 15 cattle, 12 survived.

Conclusions—Clinical course in beef cattle with an AV or RDA was more protracted than that typically associated with these conditions in dairy cattle, but survival rate in beef cattle that did not have rupture of the abomasum was sim ilar to that of dairy cattle.

Clinical Relevance—Abomasal displacement should be considered for beef cattle with abdominal distention. Prognostic indicators recommended for use in dairy cattle may not be useful for beef cattle. (J Am Vet Med Assoc 2000;216:730–733)

Abstract

Objective—To determine concentrations of 2 acute-phase proteins (serum amyloid A [SAA] and lipopolysaccharide-binding protein [LBP]) in serum samples obtained from horses with colic and identify relationships among these acute-phase proteins and clinical data.

Animals—765 horses with naturally developing gastrointestinal tract diseases characterized by colic (ie, clinical signs indicative of abdominal pain) and 79 healthy control horses; all horses were examined at 2 university teaching hospitals.

Procedure—Serum concentrations of SAA and LBP were determined by immunoturbidometric and dotblot assays, respectively.

Results—SAA and LBP concentrations were determined for 718 and 765 horses with colic, respectively. Concentrations of SAA were significantly higher in nonsurvivors than in survivors, and horses with enteritis or colitis and conditions characterized by chronic inflammation (eg, abdominal abscesses, peritonitis, or rectal tears) had SAA concentrations significantly greater than those for horses with other conditions. Serum concentrations of LBP did not correlate with outcome, disease process, or portion of the gastrointestinal tract affected.

Conclusions and Clinical Relevance—Circulating concentrations of SAA were significantly higher at admission in horses with colic attributable to conditions having a primary inflammatory cause (eg, enteritis, colitis, peritonitis, or abdominal abscesses) and were higher in horses that failed to survive the episode of colic, compared with concentrations in horses that survived. Serum concentrations of LBP did not correlate with survival. Analysis of these findings suggests that evaluation of SAA concentrations may be of use in identifying horses with colic attributable to diseases that have inflammation as a primary component of pathogenesis. (Am J Vet Res 2005;66:1509–1516)