Intranasal melanoma treated with radiation therapy in three dogs

Three dogs were investigated for chronic unilateral nasal discharge. In all cases CT imaging showed an intranasal mass causing turbinate lysis and no evidence of metastasis. Cytology in cases 1 (a 14-year-old neutered male crossbreed dog) and 2 (a five-year-old neutered male German Shepherd dog) demonstrated a pleomorphic cell population with variable intracellular pigment suspicious of melanocytic neoplasia. Histopathology with immunohistochemistry (Melan-A and vimentin, plus PNL-2 in one case) confirmed the diagnosis of melanoma in all dogs. All dogs were treated with megavoltage radiotherapy using linear accelerators. Cases 1 and 3 (a nine-year-old neutered female beagle dog) received a hypofractionated (4 × 8 Gy) protocol and case 2 received a definitive (12 × 4 Gy) protocol. Complete remission was demonstrated on repeat CT scan five months after diagnosis in case 1 and seven months in case 2. Stable disease was documented on CT at four months for case 3; however, clinical signs in this dog remained controlled for 10 months in total. Case 1 died of unrelated causes five months after diagnosis, case 2 was euthanased due to the development of seizures 13 months after diagnosis, and case 3 was lost to follow-up 12 months after diagnosis. Melanoma should be considered as a rare differential diagnosis for primary nasal neoplasia in the dog and radiation therapy can be used as effective local therapy.     

Engagement of integrins as a cellular route of invasion by bacterial pathogens

Integrins are heterodimeric receptors that mediate important cell functions, including cell adhesion, migration and tissue organisation. These transmembrane receptors regulate the direct association of cells with each other and with extracellular matrix proteins. However, by binding their ligands, integrins provide a transmembrane link for the bidirectional transmission of mechanical forces and biochemical signals across the plasma membrane. Interestingly, several of this family of receptors are exploited by pathogens to establish contact with the host cells. Hence, microbes subvert normal eukaryotic cell processes to create a specialised niche which allows their survival. This review highlights the fundamental role of integrins in bacterial pathogenesis.     

Development and validation of an ELISA to detect antibodies to Corynebacterium pseudotuberculosis in ovine sera

Several enzyme-linked immunosorbent assays (ELISAs) have been developed for the detection of antibodies to Corynebacterium pseudotuberculosis, the causative agent of caseous lymphadenitis (CLA). However, none are commercially available in the UK. It was therefore necessary to develop a new, economic ELISA for use in a research project studying the epidemiology of CLA in UK sheep. The ELISA with its diagnostic qualities is presented. The ELISA was developed using sonicated C. pseudotuberculosis and optimised to detect total antibody or IgG class antibody in serum. Receiver operating characteristic (ROC) curves were obtained and the area under the ROC curve was used to compare the sensitivity and specificity of the two ELISAs. Both versions of the ELISA were evaluated on a panel of 150 positive reference sera and 103 negative reference sera. Using the test at 100% specificity, the sensitivity of detection of total antibody was 71% (95% confidence interval 63-78%), and the sensitivity of detection of IgG antibody to C. pseudotuberculosis was 83% (76-89%), which compares favourably with other reported ELISA tests for CLA in sheep. The sensitivity of the IgG antibody assay may be higher because of the greater affinity of IgG class antibodies compared with the IgM antibodies also detected by the total antibody ELISA. The results of ROC analysis indicated that the IgG isotype ELISA was more accurate than the total antibody ELISA. The efficiency of the test was greatest when serum samples were run in a dilution series than when any single serum dilution was used. The ELISA is considered to be suitable for application in field studies of CLA in UK sheep.     

Diagnosis of cystic echinococcosis on sheep farms in the south of Argentina: areas with a control program

In 2000 Guarnera et al. proposed using ELISA in canine faeces collected from the ground to detect dogs infected with Echinococcus granulosus, thus determining sheep farms with active transmission. The objective was to evaluate the prevalence of E. granulosus infection in sheep farms of the Patagonia. Sheep farms were randomly selected in the Provinces of Río Negro, Chubut, Neuquén, Santa Cruz and Tierra del Fuego (areas with control programs) and La Pampa (comparison area). From one to three samples of fecal matter were obtained for each sheep farm, which were processed by means of copro-ELISA test with confirmation of positive samples by copro-Western blot. A total of 1042 samples were obtained from 352 sheep farms, 26 (7.3%) proving positive. Of these 5 (6.3%) were from La Pampa, 9 (13.8%) from Neuquén, 4 (4.7%) from Río Negro, 2 (2.9%) from Chubut, 1 (5.9%) from Santa Cruz and 5 (13.9%) from Tierra del Fuego. The identification of parasitized dogs is an essential activity upon which rests the strategy of control and surveillance. Arecoline tests or coproantigen test with fecal matter obtained directly from the dog contribute information on individual prevalence, while the use of coproantigens detected in ground-collected samples transfers the dog unit of observation to units of greater epidemiological value. In the present experience, the technique employed seems promising for its application in systems of epidemiological surveillance of cystic echinococcosis and in drawing a baseline on which to measure the progress of control programs in the Argentine Patagonia in subsequent years.     

Fasciola hepatica infections in livestock flock, guanacos and coypus in two wildlife reserves in Argentina

Between autumn and spring 2006, a coprological survey was performed in two wildlife reserves located in the north of Argentine Patagonia to determine the prevalence of Fasciola hepatica and the number of parasite eggs per gram (epg) of feces in wild guanacos (Lama guanicoe), coypus (Myocastor coypus), and locally born and raised goats and sheep. Snails of the Family Lymnaeidae were collected in freshwater habitats, identified taxonomically and analyzed parasitologically.Prevalence of patent infection was 100% in sheep (n = 69) and coypus (n = 9), 84% in goats (n = 20) and 0.5% in guanacos (n = 224). No significant differences in epg were found among animals, but the median epg of coypus (160) and sheep (160) was higher than that of goats (80). For guanacos and goats, a negative binomial model estimating the population egg-count frequency could be fitted, while for coypus and sheep parasite egg-count frequencies trended toward a normal distribution, indicative of a more even, and much less aggregated distribution across sampled hosts. All snails (n = 175) were Lymnaea truncatula and none of them was found infected. This is the first report of fascioliasis in free-ranging guanacos in Argentina. Coypu appears to be a major wildlife reservoir of F. hepatica, which was presumably introduced locally by livestock.     

Prognostic value of clinicopathologic variables obtained at admission and effect of antiendotoxin plasma on survival in septic and critically ill foals

This prospective study compared survival rates of critically ill and septic foals receiving 1 of 2 different types of commercial equine plasma and analyzed admission variables as possible predictors of survival. Standardized clinical, hematologic, biochemical, and hemostatic admission data were collected and foals received either conventional commercially available hyperimmune equine plasma or equine plasma specifically rich in antiendotoxin antibodies in a double-blinded, coded fashion. Sepsis was defined as true bacteremia or sepsis score >11. Overall survival rate to discharge was 72% (49/68). Foals that were nonbacteremic and demonstrated a sepsis score of < or = 11 at admission had a 95% (18/19) survival rate. The survival rate to discharge for septic foals was 28/49 (57%), with truly bacteremic foals having a survival rate of 58% (14/24), whereas that for nonbacteremic, septic foals was 56% (14/25). Sensitivity and specificity for sepsis score >11 as a predictor of bacteremia were 74 and 52%, respectively. For the entire study population, a higher survival rate to discharge was documented for those foals receiving hyperimmune plasma rich in antiendotoxin antibodies (P = .012, odds ratio [OR] 6.763, 95% confidence interval [CI]: 1.311, 34.903). Administration of plasma rich in antiendotoxin antibodies also was associated with greater survival in septic foals (P = .019, OR 6.267, 95% CI: 1.186, 33.109). Statistical analyses demonstrated that, among 53 clinical and clinicopathologic admission variables, high sepsis score (P < .001), low measured IgG concentration (P = .01), high fibrinogen concentration (P = .018), low segmented neutrophil count (P = .028), and low total red blood cell numbers (P = .048) were the most significant predictors of overall mortality.     

Identification and differentiation of European and African/Australian strains of Mycoplasma mycoides subspecies mycoides small-colony type using polymerase chain reaction analysis.

Mycoplasma mycoides subspecies mycoides small-colony type (M. m. m. SC) is the cause of the economically important contagious bovine pleuropneumonia. Isolates from Africa and Australia have previously been documented to have a fragment of approximately 8.84 kb, which is absent in European strains. A set of polymerase chain reaction (PCR) primers over this region was designed to identify M. m. m. SC isolates and separate European strains from those of Africa/Australia. Specificity of the PCR assay was achieved through the positioning of an oligonucleotide within the insertion sequence IS1296, upstream of this deletion, which then was paired with a reverse primer, upstream of the deletion, within the 8.84 kb-deleted region or downstream of the deletion, generating fragments of 1.1 kb (all M. m. m. SC strains), 1.4 kb (African/Australian strains only) and 1.3 kb (European strains only), respectively. Identification and differentiation was specific for DNA from M. m. m. SC with no amplification of DNA from other cluster members or closely related species. The PCR products did not require differentiation by use of a restriction endonuclease, and have potential for use in detection of this organism in clinical samples.     

Patterns of nodal metastases,biological behaviour and prognosis of canine mast cell tumours of the pinna: A multi-institutional retrospective study

Canine cutaneous mast cell tumours (cMCTs) of the pinna have been associated with an aggressive biological behaviour, although data remain scarce. The knowledge acquired over the past years on histologic gradings, and the value of lymph node (LN) staging, may help in better characterizing this anatomical presentation. The first aim was to describe the frequency, location, and histologic appearance of LN metastases in cMCT of the pinna. A second aim was to evaluate prognosis. Medical records of dogs with cMCT of the pinna, that underwent tumour and sentinel (SLN) or regional LN (RLN) excision, were reviewed. The influence of potential prognostic variables on time to progression (TTP) and tumour-specific survival (TSS) was investigated. Thirty-nine dogs were included: 19 (48.7%) had Kiupel high-grade (K-HG) and 20 (51.3%) had low-grade (K-LG) MCTs. Eighteen (46.1%) dogs underwent SLN mapping: the superficial cervical LN was at least one of SLN in 17 (94.4%) cases. Twenty-two (56.4%) dogs had LN metastases; the superficial cervical LN was always involved. On multivariable analysis, only K-HG was associated with increased risk of progression (p = .043) and tumour-related death (p = .021). Median TTP and TSS were 270 and 370 days in K-HG, respectively; these were not reached in dogs with K-LG tumours (p < .01). cMCTs of the pinna are often K-HG and are also associated with a higher frequency of LN metastasis; however, we confirmed the independent prognostic value of histologic grading. A multimodal treatment may lead to favourable long-term outcome. Moreover, the superficial cervical LN is most often the SLN.     

Efficacy and safety of transdermal methimazole in the treatment of cats with hyperthyroidism

The objective of this study was to determine whether transdermal methimazole was as safe and effective as oral methimazole for the control of hyperthyroidism in cats. Forty-seven cats with newly diagnosed hyperthyroidism were randomized to receive either transdermal methimazole in pluronic lecithin organogel (PLO; applied to the inner pinna), or oral methimazole (2.5 mg q12h for either route). Cats were evaluated at weeks 0, 2, and 4 with a physical exam, body weight determination, CBC, biochemical panel, urinalysis, measurement of total levothyroxine (T4) concentration, indirect Doppler blood pressure determinaiton, and completion of an owner questionnaire. Data between the 2 groups and over time were compared by nonparametric methods. Forty-four cats followed the protocol (17 oral and 27 transdermal). Significantly more cats treated with oral methimazole had serum T4 concentrations within the reference range after 2 weeks (14 of 16 cats) compared to those treated by the transdermal route (14 of 25; P = .027). This difference was no longer significant by 4 weeks of treatment (9 of 11 for oral versus 14 of 21 for transdermal), possibly because of inadequate numbers evaluated by 4 weeks. Cats treated with oral methimazole had a higher incidence of gastrointestinal (GI) adverse effects (4 of 17 cats) compared to the cats treated with transdermal methimazole (1 of 27; P = .04), but no differences were found between groups in the incidence of neutropenia, hepatotoxicity, or facial excoriations. Although the overall efficacy of transdermal methimazole is not as high as that of oral methimazole at 2 weeks of treatment, it is associated with fewer GI adverse effects compared to the oral route.     

Rural origin,age, and endoparasite fecal prevalence in dogs surrendered to the Regina Humane Society, 2013

We report the results of fecal parasite surveillance in dogs surrendered to the Regina Humane Society, Saskatchewan, Canada, between May and November 2013. Overall, 23% of 231 dogs were infected with at least 1 intestinal parasite. Endoparasite infection was positively associated with rural origin (P = 0.002) and age (< 12 months; P < 0.001).