Serovar-specific prevalence and risk factors for leptospirosis among dogs: 90 cases (1997-2002)

OBJECTIVE: To estimate serovar-specific prevalence of leptospirosis by use of veterinary teaching hospital and laboratory submission data; describe annual and seasonal patterns of leptospirosis; and identify risk factors for age, sex, and breed. DESIGN: Retrospective study. ANIMALS: 90 dogs with leptospirosis. PROCEDURES: Hospital records of dogs examined at Purdue University Veterinary Teaching Hospital with a diagnosis of leptospirosis and laboratory records of dogs from which sera were tested for antibodies against Leptospira spp at Purdue University Animal Disease Diagnostic Laboratory from 1997 through 2002 were reviewed. The likely infecting Leptospira serovar was identified. Seasonal and annual prevalences were calculated by use of hospital population at risk (hospital cases) or serologic testing submissions (diagnostic laboratory cases). Age-, sex-, and breed-specific risk factors for hospital cases were estimated by odds ratios. RESULTS: Of the 39 hospitalized dogs identified, 34 had been serologically tested, and 22 of those were infected with Leptospira kirschneri serovar grippotyphosa. Of the 51 diagnostic laboratory cases, 59% had a reciprocal titer > or = 800 against serovar grippotyphosa. Diagnostic laboratory cases were more common in summer, whereas hospital cases of leptospirosis were more common in fall. Male dogs were at significantly greater risk of leptospirosis than female dogs; and dogs 4 to 6.9 years old were at significantly greater risk than dogs < 1 year old. CONCLUSIONS AND CLINICAL RELEVANCE: L kirschneri serovar grippotyphosa infection was associated with most cases of leptospirosis in dogs. Use of an effective vaccine that includes this serovar is advisable for dogs at risk of leptospirosis.     

Transposition of the biceps tendon to reduce lateral scapulohumeral luxation in three species of nondomestic ruminant.

Open reduction of lateral luxation of the scapulohumeral joint was performed in a Mhorr gazelle (Gazella dama mhorr), a southern pudu (Pudu puda), and an Alpine ibex (Capra ibex ibex) by transposition of the biceps brachii tendon lateral to the greater tubercle of the humerus. The ibex had a very large greater tubercle that required a second osteotomy to allow successful lateral transfer of the tendon. Although all three animals were non-weight bearing in the first 2-3 wk after surgery, ambulation improved at 3 wk and was almost normal by 6 wk after surgery. Postoperative follow-up of 8 yr, 7 mo, and 3 mo in the gazelle, pudu, and ibex, respectively, revealed normal ambulation with no gait deficits. The gazelle was euthanized 8 yr after surgery for unrelated disease and necropsy demonstrated mild to moderate degenerative joint disease. Similar lateral shoulder luxations in comparably sized, nondomestic ruminants, without concurrent fractures or significant joint abnormality, have a good prognosis for return to function after surgical reduction using a biceps tendon transposition.     

The effects of phytochemical pesticides on the growth of cultured invertebrate and vertebrate cells

A range of cultured cells of invertebrate and vertebrate origin was grown in the presence of a number of phytochemical pesticides to test the effect of the latter on cell proliferation. The main observation was that azadirachtin was a potent inhibitor of insect cell replication, with an EC50 of 1.5 x 10(10) M against Spodoptera cells and of 6.3 x 10(9) M against Aedes albopictus cells, whilst affecting mammalian cells only at high concentrations (> 10(-4) M). As expected, the other phytochemical pesticides, except for rotenone, had little effect on the growth of the cultured cells. Rotenone was highly effective in inhibiting the growth of insect cells (EC50:10(-8) M) but slightly less toxic towards mammalian cells (EC50:2 x 10(-7) M). Neem terpenoids other than azadirachtin and those very similar in structure significantly inhibited growth of the cell cultures, but to a lesser degree. The major neem seed terpenoids, nimbin and salannin, for example, inhibited insect cell growth by 23% and 15%, respectively.     

BILATERAL PERINEPHRIC PSEUDOCYSTS AND POLYCYSTIC KIDNEYS IN A FERRET

A 3-year-old castrated male domestic ferret was evaluated for abdominal distention. Survey lateral and dorsoventral abdominal radiographs were made. There were two soft tissue radiopacities consistent with grossly enlarged kidneys displacing small bowel and colon cranially, ventrally and caudally. Abdominal ultrasound was performed and revealed bilateral perinephric pseudocysts and polycystic kidneys. The perinephric pseudocysts were found to be dilated renal capsules on exploratory surgery and were drained. On follow up examinations, the pseudocysts were drained by ultrasound-guided paracentesis. The perinephric cyst fluid was distinguished from urine by measuring creatinine concentration and plans were made to resect the renal capsules due to rapid re-accumulation of pseudocyst fluid. The ferret's condition deteriorated and euthanasia was performed. Post-mortem examination was declined by the owner. Perinephric pseudocysts are rare and this is the first published report in a ferret. Ultrasound examination is the most rapid, accurate and non-invasive method for diagnosis of perinephric pseudocysts.     

Feline Lymphoma (145 Cases): Proliferation Indices, Cluster of Differentiation 3 Immunoreactivity, and Their Association with Prognosis in 90 Cats

Paraffin-embedded, formalin-fixed tissue samples from 145 cats with lymphoma were analyzed for cluster of differentiation 3 (CD3, a surface antigen) immunoreactivity, argyrophilic nucleolar organizer region (AgNOR) frequency, and proliferating cell nuclear antigen labeling index (PCNA-LI). This information along with signalment, anatomic site, and feline leukemia virus (FeLV) antigen status was used to determine the potential of these indicators to predict response to therapy, remission, and survival times, and to characterize cats with lymphoma in the era of general availability of FeLV testing and vaccination. Alimentary lymphoma, primarily occurring in older, FeLV-negative cats, was the most common site of involvement. Although the majority of tumors from FeLV-positive cats were CD3-immunoreactive, only one half of CD3-immunoreactive tumors occurred in FeLV-positive cats. Median remission duration and survival times were 126 days and 143 days, respectively, for all cats. Measures of tumor cell proliferation (AgNOR frequency and PCNA-LI) and CD3-immunoreactivity were not predictive of outcome. When all prognostic factors were accounted for by multivariate analysis, response to therapy, FeLV status, and clinical substage were predictive of outcome. FeLV-negative cats that achieved a complete response following induction therapy were likely to have durable (ie, > 6-month) responses, particularly when doxorubicin was included in the chemotherapy protocol. However, FeLV-positive cats had significantly shorter remission and survival times with available chemotherapeutic protocols.     

Streptococcus ictaluri arthritis, osteolysis, myositis, and spinal meningitis in channel catfish broodstock

This report details findings of an investigation into complaints by commercial fingerling producers of low-grade mortalities, poor reproductive success, emaciation, skin lesions, and severely arched backs among broodstock of channel catfish Ictalurus punctatus. Gross lesions involved the jaw, fin bases, and vertebral column. Jaw and fin lesions consisted of small hemorrhagic ulcers and exudate-filled tracts that communicated with underlying joints and destroyed their articular surfaces. Spinal changes, recognized grossly by severe arching of the proximal vertebral column, resulted from the collapse and displacement of vertebral bodies, causing compression of the spinal cord. Affected vertebrae were lysed by pyogranulomatous inflammation that infiltrated into adjacent muscle and the spinal canal. A Streptococcus-like organism was visualized in exudate and isolated repeatedly from lesions, but only once from the kidney of a single fish. Preliminary analysis of a 16S ribosomal DNA sequence showed a close relationship to S. iniae, S. parauberis, and S. canis. Koch's postulates were fulfilled after challenge with and reisolation of the agent from identical lesions that appeared at fin bases at 2 weeks postinjection. Historical evidence and gross and microscopic findings imply the presence of a pathogen of low virulence that is capable of producing severe localized infections after a brief period of septicemia. The disease presents as a chronic debilitating syndrome that is sufficient to inhibit mobility, feeding, and reproductive activity in affected fish. Complete biochemical and molecular characterization of the bacterium (published elsewhere) has established the agent as a novel species, S. ictaluri.