The frequent detection of a treponeme in bovine digital dermatitis by immunocytochemistry and polymerase chain reaction

A study was carried out to determine whether spirochaetes are frequently associated with digital dermatitis in United Kingdom (UK) dairy cattle. Histopathological examination of lesions using a silver stain showed a large number of unidentified spirochaete-like organisms present in digital dermatitis hoof skin tissue in all examined biopsies. Immunocytochemical staining demonstrated that spirochaetes in skin lesions were identified by polyclonal antisera to Borrelia burgdorferi, Treponema denticola and Treponema vincentii (again all biopsies were positively stained), whereas monoclonal antibodies to B. burgdorferi and any Treponema pallidum did not stain any organisms in all biopsies. A PCR of 16S rRNA, previously shown to be specific for a new treponeme, was employed and produced positive results from 82.4% of digital dermatitis tissues. It is concluded that this spirochaete (or related spirochaetes), which is similar to human oral treponemes, is frequently associated with, and may be responsible for, pathological changes in digital dermatitis.     

A Combination Chemotherapy Protocol (VELCAP-L) for Dogs with Lymphoma

Ninety-eight dogs with lymphoma treated with a 5-drug combination chemotherapy regimen (vincristine, L-asparaginase. cyclophosphamide, doxorubicin, prednisone [VELCAP-L]) were evaluated for pretreatment characteristics predictive for response and remission duration. The complete remission rate was 69%, with a median remission duration of 55 weeks. Dogs with advanced stage of disease, constitutional signs, dogs that were older, and dogs that were dyspneic were less likely to achieve remission. Once in remission, small dogs and dogs without pretreatment thrombocytopenia were likely to have longer remission duration. Toxicoses were frequent, but rarely fatal, and no predictitive factors were found for a dog developing toxicoses. VELCAP-L is an effective treatment for dogs in stage I-III lymphoma, particularly in young, small animals.     

Tonometry in three herbivorous wildlife species

Tonometry was performed to estimate intraocular pressure (IOP) in 12 Nubian ibexes ( Capra ibex nubiana ), 10 Grant zebras ( Equus burchelli  ) and five Arabian oryxes ( Oryx leucoryx ), using both applanation (Tono-Pen) and/or indentation (Schiotz) tonometers. Animals were anesthetized with a mixture of etorphine hydrochloride and acepromazine maleate. Mean (± SD) IOP in the ibex was 17.95 ± 4.78 mmHg (24 eyes, indentation tonometry). In the zebra, indentation tonometry (20 eyes) yielded a mean IOP of 25.30 ± 3.06 mmHg, and applanation tonometry (six eyes) yielded a mean IOP of 29.47 ± 3.43 mmHg. In the oryx, indentation tonometry (five eyes) yielded a mean IOP of 22.68 ± 8.15 mmHg, and applanation tonometry (10 eyes) yielded a mean IOP of 11.76 ± 3.43 mmHg. There were no significant effects of gender, age, weight, side or reading number on the IOP measured in any of the three species. No significant differences were found between the IOP of the three species, nor between the readings of the two instruments, although some of the P -values were close to the significance level.     

Immune responses to Mycoplasma bovis vaccination and experimental infection in the bovine mammary gland.

This study characterized the immune responses in four vaccinated and four control cows in response to vaccination and experimental intramammary inoculation with Mycoplasma bovis. Specific antibody responses occurred in serum and milk in response to vaccination and experimental infection. Lymphocytes from peripheral blood, but not from the mammary gland of vaccinated cows had increased responsiveness to mitogens. No lymphocytes tested were responsive to M. bovis antigen. Both vaccination and experimental infection resulted in skin test reactivity. These results imply that vaccination results in immune responses which may alter the course of experimental M. bovis mastitis, but may contribute to cellular inflammation.     

Tryptamine alkaloid toxicosis in feedlot sheep

Tryptamine alkaloid toxicosis (Phalaris staggers) was diagnosed in feedlot sheep. Clinical signs of toxicosis, which were exacerbated by excitement, included gait abnormalities, muscular tremors, nystagmus, and convulsions. An estimated 8% of the most severely affected lambs had clinical signs of toxicosis. Gross lesions detected in the brain of affected lambs consisted of focal gray-green discoloration in the brain stem and thalamus; these areas had microscopic evidence of intraneuronal pigment accumulation. Brain specimens obtained at slaughter indicated that 60% of the lambs had lesions consistent with tryptamine alkaloid toxicosis. Tryptamine alkaloids were found in low concentrations in the feed. Lambs exposed to these feeds had higher death losses than those that were not exposed to the feeds. Cobalt concentration in the feed was higher than that previously reported to be associated with Phalaris staggers.     

Pandemic (H1N1) 2009 influenza A virus infection associated with respiratory signs in sloth bears (Melursus ursinus)

In 2009, a pandemic influenza A virus (pH1N1) spread globally in humans and infected a broad range of captive animals with close human contact. In February 2014, a pH1N1 virus was isolated from a sloth bear with respiratory signs at a US zoo, demonstrating that recurring epidemics present an ongoing threat to animals, including threatened species. This is the first report of pH1N1 infection in sloth bears. To understand the sloth bear virus within the global context of pH1N1, phylogenetic trees were inferred including full‐length sequences from available non‐human, non‐swine hosts, representing four families in the order Carnivora and one order of birds. A combination of phylogenetic and epidemiological evidence strongly suggests the sloth bear was infected with a human‐origin pH1N1 virus, supporting the implementation of biosecurity measures to protect human and animal health.     

Phenotyping Castanea hybrids for Phytophthora cinnamomi resistance

Castanea sativa is susceptible to Phytophthora spp., a serious root pathogen causing ink disease, while C. crenata and C. mollissima show resistance to infection. Interspecific controlled crosses were established for introgression of resistance genes from the resistant species into the susceptible C. sativa, and two mapping populations were created. Phytophthora cinnamomi resistance of each progeny was evaluated by root and excised shoot inoculation tests. The number of days of survival after root inoculation was the best discriminator of resistance to P. cinnamomi while the percentage of shoots with internal lesions was the symptom most associated with survival. The lesion progression rate in the excised shoot inoculation test was strongly and negatively correlated with survival in the root inoculation test. The excised shoot inoculation test appears to be a reliable approach for screening the resistance of chestnut genotypes to P. cinnamomi. Strong genetic correlations were obtained between survival and ink disease symptoms and among symptoms, indicating that common or linked genes might influence resistance to P. cinnamomi. The most resistant genotypes selected from this study will be tested for other commercial variables, such as ease of vegetative propagation and stock–scion compatibility.     

Propylthiouracil-associated hemolytic anemia, thrombocytopenia, and antinuclear antibodies in cats with hyperthyroidism

Nine of 105 cats with hyperthyroidism treated with propylthiouracil developed a serious immune-mediated drug reaction during treatment. Adverse clinical signs, which developed after 19 to 37 days (mean, 24.8 days) of propylthiouracil administration, included lethargy, weakness, anorexia, and bleeding diathesis. Physical examination revealed pale mucous membranes, and petechial hemorrhages of the skin and oral cavity. Results of hematologic testing revealed severe anemia and thrombocytopenia. The direct antiglobulin (Coombs') test was positive in all 7 cats evaluated, whereas the serum antinuclear antibody titer was greater than or equal to 1:10 in 5 of the 8 cats tested. In 4 of the cats, treatment included appropriate supportive therapy and cessation of propylthiouracil; in these cats, anemia and thrombocytopenia resolved and Coombs' and antinuclear antibody tests became negative within 2 weeks.