Prevalence of Ehrlichia canis infection in thrombocytopenic dogs from Rio de Janeiro, Brazil

BACKGROUND: Infection with Ehrlichia canis causes a highly variable, multisystemic disease in dogs. Nevertheless, many clinicians in Rio de Janeiro, Brazil, use the presence of only thrombocytopenia to make a presumptive diagnosis of E canis infection. OBJECTIVE: The objective of this study was to determine the prevalence of E canis in thrombocytopenic dogs from Rio de Janeiro, Brazil, using polymerase chain reaction (PCR). METHODS: Following DNA extraction of whole blood samples from 226 dogs, PCR assays were done using primers for rickettsial DNA (including Ehrlichia spp, Anaplasma platys and A phagocytophilum) and using E canis-specific primers (16S rRNA gene). Dogs were grouped as thrombocytopenic and nonthrombocytopenic based on platelet counts. The null hypothesis that there was no difference in the prevalence of E canis in these groups was rejected at P<.05. RESULTS: Thirty-six (32.1%) of the thrombocytopenic dogs and 4 (3.5%) of the nonthrombocytopenic dogs were positive for rickettsial gene sequences (P<.0001). Further, 30 (26.8%) of thrombocytopenic dogs and 4 (3.5%) nonthrombocytopenic dogs were positive for E canis-specific gene sequences (P<.0001). CONCLUSIONS: Although the prevalence of E canis infection was higher in thrombocytopenic dogs, less than one third of these dogs had demonstrable E canis infection. Thus, thrombocytopenia is not specific for the detection of E canis infection and should not be used solely to establish a diagnosis of canine ehrlichiosis, even in a geographic area with relatively high disease prevalence.     

Comparison of prices paid for feeder calves sold at conventional auctions versus special auctions of vaccinated or conditioned calves in Ontario

OBJECTIVE: To determine whether vaccinated or conditioned feeder calves sold through special auctions in Ontario commanded a premium, compared with feeder calves sold at conventional auctions, and whether various physical characteristics of the calves were associated with the sale price. DESIGN: Cross-sectional study. ANIMALS: 14,037 calves sold through conventional and special auctions at the Keady Livestock Market during the fall of 1999 and 2000. PROCEDURE: Calves were observed as they were sold by lot in the auction ring. Lot characteristics and the price received for each lot were recorded. Multivariate analysis was used to estimate the effect of lot characteristics and sale type on price. RESULTS: Information was recorded for 2,601 calf lots. Multivariate analysis indicated that various lot characteristics were associated with sale price, with 68% of the variation explained by the model. Overall, lots sold at special auctions received a premium of 0.06 dollars/lb (Canadian dollars), compared with lots sold at conventional auctions. However, the premium varied with mean body weight of the lot and year. In addition, frame size, breed, body condition score, uniformity of the lot, weaning status, mean body weight, lot size, sex, year, and sale type were significantly related to sale price. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that producers selling calves at special auctions at this market received a premium, compared with producers selling calves at conventional auctions.     

Design and organization of an equine intensive care unit.

Careful planning and design of a new ICU are warranted to maximize use of the facility, minimize the risk of hospital-acquired infection, and improve overall patient outcome. In addition, personnel satisfaction improves with an improved work environment. A functional equine ICU is also tailored to the geographic area, local needs of the practice, and anticipated investment.     

Nd:YAG laser-assisted modified Forssell's procedure for treatment of cribbing (crib-biting) in horses

OBJECTIVE: To report an neodymium:yttrium-aluminum garnet (Nd:YAG) laser-assisted modified Forssell's surgical technique and outcome for treatment of cribbing (crib-biting) in horses. STUDY DESIGN: Retrospective clinical study. ANIMALS: Ten adult horses with stereotypic cribbing behavior. METHODS: Data were obtained from medical records and telephone conversations with owners, trainers, and veterinarians. Surgical technique involved an approximately 34-cm ventral median skin incision starting rostral to the larynx and extending caudally. A 10-cm section of the ventral branch of the spinal accessory nerve was removed, using an Nd:YAG laser at 25 W and continuous pulse with a contact, sculpted-fiber tip. After neurectomy, approximately 34-cm sections of the paired omohyoideus and sternothyrohyoideus muscles were removed starting 2 cm rostral to the ventral aspect of the larynx, at the basihyoid bone, using the Nd:YAG laser. RESULTS: Median horse age was 7 years (range, 1 to 11 years). Median surgical time was 90 minutes (range, 75 to 130 minutes). Long-term outcome (range, 7 to 72 months) was available for all horses. None of the horses had cribbing behavior after surgery, and all returned to their previous use. Four horses had complications (two of which were unrelated to the surgical site), but all recovered fully. CONCLUSION: The successful outcome we obtained is better than reported previously using a modified Forssell's technique. CLINICAL RELEVANCE: Surgical treatment for cribbing by Nd: YAG laser-assisted myectomy and neurectomy resulted in an excellent prognosis for resolution of the stereotypical behavior with minimal complications.     

Fecal polymerase chain reaction with 16S ribosomal RNA primers can detect the presence of gastrointestinal Helicobacter in dogs

Questions about pathogenesis and therapy for Helicobacter infections in dogs could be answered with a simple, noninvasive, sensitive, and specific diagnostic test. We hypothesized that a fecal polymerase chain reaction (PCR) assay would detect Helicobacter and could be useful for assessing therapeutic responses. Paired gastric biopsies and fecal samples were obtained from 39 random source dogs (group 1). Gastric biopsies from each of these dogs had histologic evidence of gastric spiral bacteria, and paired gastric tissue and fecal samples produced a 375-base pair (bp) product when amplified by PCR with Helicobacter-specific primers. Specificity of the PCR product was confirmed by detection of expected 60-, 119-, and 196-bp products following Hinfl digestion. Direct sequencing of amplicons from paired PCR products from gastric biopsy and fecal samples from 8 group I dogs showed that gastric products had the highest homologies with known gastric Helicobacter species, whereas fecal products had the highest homologies with intestinal species. Healthy mixed-breed dogs (group II; n = 8) with histologically confirmed spiral bacteria infection were treated with a 21-day course of metronidazole, amoxicillin, and famotidine. Fecal samples were collected from group II dogs twice before and within 3 days of completion of treatment. The PCR results correctly identified 15/16 pretreatment samples as positive: 1 pretreatment sample was negative. PCR results identified 8/8 posttreatment samples as Helicobacter negative. Fecal PCR is a useful test for detecting Helicobacter infection in dogs. This assay may be useful as a screening test for infection and could be used to address questions relevant to pathogenesis and therapy.     

Training veterinary personnel for effective identification and diagnosis of exotic animal diseases

The requirements for exotic animal disease (EAD) training were considered at a workshop organized for those with responsibilities for EAD response management in the different states of Australia, with the objective of identifying the optimum strategy for training veterinarians to identify and act upon EADs. It was concluded that there should be specialized within-country training in EAD recognition for an elite group of diagnostic veterinarians who are required to recognize the major exotic diseases of animals, instigate the correct procedures to confirm the diagnosis of the disease, and undertake appropriate measures for effective initial management of the disease. The use of live, deliberately infected animals for demonstration purposes is not currently supported by any research indicating an improved learning outcome compared with that from alternatives, such as videos, necropsy specimens, and dedicated computer-aided learning packages. Therefore, ethical requirements to minimize the use of animals in teaching and research may prevent live-animal use. It is concluded that training should take place within each country via a course of instruction that includes an initial intensive course followed by continued professional development, with examination of knowledge at the end of each.