The effect of color type on early wound healing in farmed mink (Neovison vison).

BACKGROUND: Individual differences of mink, including color type, are speculated to affect the course of wound healing, thereby impacting wound assessment and management on the farms, as well as the assessment of wounds in forensic cases. In this study, we examined the effect of color type on early wound healing in farmed mink. Full thickness excisional wounds (2 × 2 cm) were made on the back in 18 mink of the color types Brown, Silverblue and Blue Iris. Gross and microscopic pathology of the wounds was evaluated 2 days post-wounding together with degree of wound size reduction, presence of bacteria and blood analyses. RESULTS: Pathological examination on day 2 showed the greatest mean wound size reduction in Brown mink (11.0%) followed by Blue Iris (7.9%) and Silverblue (1.6%). Bacteria were cultured from all wounds, and predominantly Staphylococcus species were recovered in mixed or pure culture. Histopathology from day 2 wounds showed a scab overlying necrotic wound edges, which were separated from underlying vital tissue by a demarcation zone rich in polymorphonuclear leukocytes. Fibroblasts and plump endothelial cells were more numerous in the deeper tissues. Complete blood count parameters were within normal ranges in most cases, however, the mink showed mildly to markedly decreased hematocrit and six mink of the color types Silverblue and Blue Iris showed moderately elevated numbers of circulating segmented neutrophils on day 2. There was a marked increase in concentration of serum amyloid A from day 0 to day 2 in all color types. CONCLUSIONS: We have described differences in early wound healing between mink of the color types Brown, Silverblue and Blue Iris by use of an experimental wound model in farmed mink. The most pronounced difference pertained to the degree of wound size reduction which was greatest in Brown mink, followed by Blue Iris and Silverblue, respectively.

Experimental Pseudomonas aeruginosa mediated rhino sinusitis in mink.

OBJECTIVES: The nasal and sinus cavities in children may serve as reservoirs for microorganisms that cause recurrent and chronic lung infections. This study evaluates whether the mink can be used as an animal model for studying Pseudomonas aeruginosa mediated rhino-sinusitis since there is no suitable traditional animal model for this disease. METHODS: Nasal tissue samples from infected and control mink were fixed in formalin, demineralized, and embedded in paraffin. A histological examination of sections from the infected animals revealed disintegration of the respiratory epithelium lining the nasal turbinates and swelling and edema of the submucosa. The expression of mucins and sialylated glycans was examined using immunohistochemistry. RESULTS: MUC1, MUC2 and MUC5AC were upregulated in the inoculated animals as a much stronger staining was present in the respiratory epithelium in the infected animals compared to the controls. The goblet cells in the nasal epithelium from the infected mink showed high affinity to the Maackia amurensis lectin and anti-asialo GM1 indicating a high concentration of α2-3 sialic acid respectively ßGalNAc1-4Galß containing glycans in these mucin producing cells. The nasal cavity in the infected mink shows features of carbohydrate expression comparable to what has been described in the respiratory system after Pseudomonas aeruginosa infection in humans. CONCLUSION: It is suggested that the mink is suitable for studying Pseudomonas aeruginosa mediated rhino-sinusitis.

Foot Lesions in Farmed Mink (Neovison vison): Pathologic and Epidemiologic Characteristics on 4 Danish Farms.

The aim of this study was to evaluate gross and histologic lesions and epidemiologic factors of foot lesions in farmed mink. The feet of 1159 mink from 4 Danish farms were examined and lesions described. Swabs from the lesions were taken from 27 mink for microbiology, and tissue samples from a representative spectrum of feet with and without lesions (n= 22) were examined histologically. Feet were grouped according to gross inspection: no lesions (55.1%), hair loss (7.1%), hyperkeratosis (35.8%), and crusting (5.3%). Lesions were predominantly located in plantar metatarsal skin (98.1%). Staphylococci were the most prevalent microorganisms cultured from the lesions. There was a significant association between presence of lesions and sex (P< .0001), age (P< .0001), and color type (P= .023). Lesion size was significantly different between hair loss and crusts and between hyperkeratosis and crusts (P< .0001). Histologically, lesions included varying degrees of orthokeratotic to parakeratotic hyperkeratosis and granulomatous to pyogranulomatous dermatitis with trichogranulomas as a dominant feature in all mink. The gross and microscopic lesions were comparable to physically induced changes in other species that develop as a response to repetitive friction or pressure. The condition may have an impact on animal welfare in mink production.

Typing of Pseudomonas aeruginosa from hemorrhagic pneumonia in mink (Neovison vison).

Hemorrhagic pneumonia in mink (Neovison vison) is caused by Pseudomonas aeruginosa and is an acute and fatal disease in farmed mink. Earlier work has demonstrated that some outbreaks of hemorrhagic pneumonia are caused by pathogenic strains while most outbreaks are caused by local strains. The objective of this study was to determine the genetic and geographical relationship among outbreaks of hemorrhagic pneumonia by pulsed-field gel electrophoresis typing of P. aeruginosa isolates. Furthermore, chosen isolates were typed by a commercial genotyping method based on single nucleotide polymorphisms (SNPs) and compared to a larger dataset of human and environmental origin. The bacterial isolates were obtained from diagnostic samples from 2002 to 2009 and contained 164 isolates from 95 outbreaks on 90 farms. Our results show that most outbreaks of hemorrhagic pneumonia in mink are caused by distinct strains of P. aeruginosa. We also identified related P. aeruginosa strains which, together with two prevalent but unrelated clones, caused one third of the outbreaks of hemorrhagic pneumonia supporting the sparse literature on this subject. None of the SNP typed strains were identified in a large dataset of human and environmental origin.

Serovars of Salmonella from captive reptiles.

The distribution on serovars of 60 Salmonella isolates from reptiles kept in captivity in Denmark during the period 1995-2006 was investigated. The isolates were all recovered from clinical specimens submitted to the National Veterinary Institute. A majority of the samples were from reptiles in zoological gardens or similar, while a minor number was from reptiles kept in private homes. A total of 43 serovars were detected, most of them being what is usually called exotic serotypes, and many not having a trivial name, while a few isolates belonged to well-known human pathogenic serovars, such as S. Enteritidis, S. Typhimurium, S. Bovismorbificans. One isolate was rough and two were non-typeable. Isolates from turtles belonged to the subspecies enterica, while many isolates from both sauria and snakes belonged to other subspecies. The findings underline the potential zoonotic risk by handling reptiles in zoological garden or other public settings, or keeping pet reptiles in private homes.

High-throughput immunophenotyping of 43 ferret lymphomas using tissue microarray technology.

To validate the use of the tissue microarray (TMA) method for immunophenotyping of ferret lymphomas, a TMA was constructed containing duplicate 1-mm cores sampled from 112 paraffin-embedded lymphoma tissue specimens obtained from 43 ferret lymphoma cases. Immunohistochemical (IHC) expression of CD3, CD79alpha, and Ki-67 (MIB-1) was determined by TMA and whole mount (WM) staining of each individual case for result comparison. There was a high correlation between CD79alpha and CD3 results comparing ferret TMA and WM sections (kappa statistic 0.71-0.73 for single-core TMA and 0.79-0.95 for duplicate-core TMA) and between continuous data from Ki-67 staining of ferret TMA sections and WM sections (concordance correlation coefficients 0.77 for single cores and 0.87 for duplicate cores). Subsequently, a panel of commercially available antibodies was applied to the TMA for the analysis of expression in ferret lymphomas. The results of this study confirmed previously published results suggesting specific cross-reactivity of the applied IHC markers (CD3, CD79alpha, Ki67) with ferret lymphoma tissue. Other IHC markers (CD45Ro, bcl2, bcl10, MUM1, CD30, vimentin) were also expressed in subsets of the included ferret lymphomas. Further studies are necessary to determine the usefulness of these markers for diagnostic and prognostic evaluation of ferret lymphomas. In conclusion, the TMA technology was useful for rapid and accurate analysis of protein expression in large archival cohorts of ferret lymphoma cases.

Distemper virus as a cause of central nervous disease and death in badgers (Meles meles) in Denmark.

During the summer of 2002 a distemper-like disease was observed in the free-ranging badger population in Denmark. It was characterised by grand seizures, abnormal behaviour and death; the badgers all had severe chronic pneumonia and some had non-suppurative encephalomyelitis. In this study, eight of the affected badgers were examined by gross pathological, histological, immunohistological, bacteriological, parasitological and virological methods, and were diagnosed with distemper; canine distemper virus was identified.

Leukoerythroblastosis and normoblastemia in the cat.

Over a six-month period, 6% of 313 cats evaluated hematologically had either leukoerythroblastosis or normoblastemia. Diseases associated with these hematological conditions included haemobartonellosis, hepatic lipidosis, trauma, viral and bacterial infections, myeloproliferative disorders, and hemangiosarcoma. The finding of leukoerythroblastosis or normoblastemia may aid in diagnosing cats presenting with nonspecific signs.

[Effects of human interferons and 60cobalt radiation on canine and feline tumour cells-preclinical studies]. / Human-Interferon und 60Kobalt-Bestrahlung bei Tumorzellen des Hundes und der Katze--präklinische Studien.

This study examined the effects of recombinant human interferons (rHuIFN) alpha 2a, alpha 2b and gamma on canine and feline tumour-cell proliferation and radiosensitivity. Sensitivity of the cell lines to radiation and rHuIFN varied according to the histologic origin of the cells. In radiation experiments, one fraction of 400 cGy produced survival rates of between 76 and 25%. Sensitivity to IFN was higher in cell lines derived from round cell tumours compared to those derived from solid tumors. At doses of 100 and 1000 U/ml IFN alpha and IFN gamma, survival rates of between 70 and 80% were observed. In combined treatment experiments, increase in IFN or radiation dose produced higher cell kills. Increasing the number of fractions had the most pronounced effect. Even small doses of human interferons can have significant effects on animal tumour cells in vitro.

Evaluation of dogs and cats with tumors of the ear canal: 145 cases (1978-1992).

OBJECTIVE: To characterize the frequency, clinical signs, biologic behavior, and response to treatment of tumors of the ear canal in dogs and cats. DESIGN: Retrospective analysis of medical records. ANIMALS: Medical records of 81 dogs (48 malignant tumors, 33 benign tumors) and 64 cats (56 malignant tumors, 8 benign tumors). PROCEDURE: Data were analyzed for cats and dogs with malignant tumors, and risk factors were analyzed for their potential impact on survival time. RESULTS: Malignant tumor types most commonly reported included ceruminous gland adenocarcinoma, squamous cell carcinoma, and carcinoma of undetermined origin. Median survival time of dogs with malignant aural tumors was > 58 months, whereas that of cats was 11.7 months. A poor prognosis was indicated by extensive tumor involvement (dogs) and by neurologic signs at time of diagnosis, diagnosis of squamous cell carcinoma or carcinoma of undetermined origin, and invasion into lymphatics or blood vessels (cats). CLINICAL IMPLICATIONS: Malignant tumors of the ear canal in dogs and cats have a propensity for local invasion, but tend not to metastasize. Squamous cell carcinoma and carcinoma of undetermined origin were the most locally aggressive tumors. Malignant tumors of the ear canal are best managed by aggressive surgical excision. Radiotherapy may be useful when tumors cannot be completely removed.

Amputation and carboplatin for treatment of dogs with osteosarcoma: 48 cases (1991 to 1993).

Forty-eight dogs with histologically confirmed appendicular osteosarcoma (OSA) entered a prospective clinical trial evaluating treatment with amputation and up to 4 doses of carboplatin given every 21 days. The median disease-free interval (DFI) was 257 days, with 31.2% of the dogs disease-free at 1 year. The median survival time was 321 days, with 35.4% of the dogs alive at 1 year. Dogs with proximal humeral OSA had shorter DFI (P = .016) and survival (P = .037) times than dogs with OSA at other locations. Dogs with lower body weights ( < 40 kg) had longer DFI (P = .0056) and survival (P = .007) times than larger dogs. Survival times for dogs that received carboplatin were statistically longer than those previously reported for amputation alone (P < .001). DFI and survival times are similar to those previously reported for 2 to 4 doses of cisplatin. Carboplatin appears to be a well-tolerated chemotherapeutic drug that can be given safely every 21 days at a dose of 300 mg/m2. Neutropenia was the dose-limiting toxicity in this study.

Prognostic factors in dogs with osteosarcomas of the flat or irregular bones.

The medical records of 45 dogs with histopathologically confirmed osteosarcomas arising from flat or irregular bones were reviewed. Thirty-five percent of the dogs eventually developed metastases. Telangectatic tumors and tumors arising from the rib and scapula had the highest prevalence of metastases. Survival times were short, with an overall median survival time of 120 days. Anatomic site, body weight, and completeness of surgical excision were found to be prognostic factors. Dogs with mandibular osteosarcomas in this study had shorter survival times than those times recently reported. 21 Local recurrence was the most common cause of death or euthanasia in this population of dogs.

Hepatic neoplasia in the dog and cat.

The histopathologic types of liver tumors in dogs and cats are reviewed with particular emphasis on the presenting signs and distribution within the liver. Ultrasonographic findings are discussed, as well as laboratory abnormalities. Finally, treatment options, prognoses, and survival times are presented, including chemotherapy protocols.

Cutaneous hemangiosarcoma in 25 dogs: a retrospective study.

Hemangiosarcomas confined to the skin and underlying muscle were surgically excised in 25 dogs. Tumors were staged based on their histological location (ie, dermal, hypodermal, and deep). Dermal (stage I) hemangiosarcomas were small, most commonly ventral-abdominal or prepucial in location, and were associated with prolonged survival times (median survival, 780 days). Tumors with hypodermal (stage II) and underlying muscular involvement (stage III) were grouped together because of their larger size, bruise-like appearance, lack of anatomic predilection, biological behavior, and shorter survival times (median survival of 172 and 307 days for dogs with stages II and III, respectively). We conclude that dermal hemangiosarcomas may be effectively treated with surgery alone, whereas hemangiosarcomas located within the hypodermal tissues bear a poor prognosis and warrant wide surgical excision with adjuvant chemotherapy.

Survey of statistical methods used in the veterinary medical literature.

Articles published in 1992 in 6 veterinary journals were reviewed. In 51% of the articles, statistical analyses were not performed or only descriptive statistics (eg, mean, median, standard deviation) were used. The most commonly used statistical tests were ANOVA and t-tests. Knowledge of 5 categories of statistical methods (ANOVA, t-tests, contingency tables, nonparametric tests, and simple linear regression) permitted access to 90% of the veterinary literature surveyed. These data may be useful when modifying the veterinary curriculum to reflect current statistical usage.

Treatment of tumor-bearing dogs with actinomycin D.

Fifty dogs with advanced malignancies were treated with actinomycin D at doses ranging from 0.5 to 1.1 mg/m2 every 3 weeks. The greatest number of responses was noted in dogs with lymphoma, including dogs that had received prior chemotherapy. Other responding tumor types included anal sac adenocarcinoma, perianal adenocarcinoma, squamous cell carcinoma, thyroid carcinoma, and transitional cell carcinoma. The median time to maximum response for dogs with lymphoma was 7 days, with a median duration of 42 days. Gastrointestinal toxicity was the most frequently observed side effect. A dose of 0.6 to 0.7 mg/m2 appears to be appropriate for treating various malignancies in dogs.

Unexpected neurotoxicity in dogs receiving a cyclophosphamide, dactinomycin, and 5-fluorouracil chemotherapy protocol.

An inexpensive combination chemotherapy protocol containing cyclophosphamide, dactinomycin, and 5-fluorouracil was evaluated in dogs with carcinomas. Fifteen dogs were entered in this study, and there were 1 complete response and 2 partial responses among 12 evaluable dogs. However, 6 of 15 dogs (40%) developed neurotoxicity. The neurotoxicity of this protocol was compared with a previous 5-fluorouracil-containing protocol and found to be significantly higher. Due to the unacceptably high rate of neurotoxicity, this protocol cannot be recommended for use in dogs with cancer.

Comparison of two indwelling central venous access catheters in dogs undergoing fractionated radiotherapy.

Twenty dogs with neoplasms requiring multiple radiation treatments received either percutaneous vascular access catheters (PVACs; Cook, Bloomington, IN) or subcutaneous vascular access ports (SVAPs; Vascular-Access-Ports, Norfolk Medical Products, Inc., Skokie, IL); 10 dogs were entered in each group. All catheters were implanted and removed aseptically and the catheter tips were cultured during implant removal. Complications with PVACs included mild incisional swelling and redness and accidental severance or rupture of the catheter. Complications with SVAPs included incisional or port swelling, bruising or redness, hematoma formation, and pain. Ports in 4 of these dogs could not be used for 1 to 3 days after surgery because of swelling and pain. Surgical wound complications, when pooled for comparison, occurred significantly more frequently with the SVAPs (P = .023). Wound complications associated with both catheters were self-limiting and resolved within 7 days. Bacterial cultures were positive in two PVACs and four SVAP tips, however, none of these dogs had clinical signs of infection or sepsis. Although both types of indwelling catheters were functional in a clinical setting, PVACs were preferred to SVAPs for dogs undergoing radiation therapy because of decreased time for implantation and fewer overall complications.

Acute sterile hemorrhagic cystitis after a single intravenous administration of cyclophosphamide in three dogs.

Three dogs receiving cyclophosphamide IV as part of a combination chemotherapeutic regimen developed macrohematuria, stranguria, and pollakiuria within 24 hours of administration of the first dose of this drug. An 11-year-old spayed mixed-breed dog with an oral squamous cell carcinoma was administered 250 mg of cyclophosphamide/m2 of body surface, whereas a 4-year-old castrated male Gordon Setter was treated with 100 mg of cyclophosphamide/m2 and a 6-year-old male German Shepherd Dog with a cutaneous hemangiosarcoma was administered 140 mg of cyclophosphamide/m2. Aerobic bacterial culture, antimicrobial susceptibility testing, and urinalysis were performed on urine obtained by cystocentesis from all 3 dogs after hematuria was observed. Sterile hemorrhagic cystitis was diagnosed on the basis of large numbers of RBC in the urine, lack of pathogens on bacterial culturing of urine, and clinical signs. Although cyclophosphamide-induced cystitis in dogs has been reported in the literature numerous times, acute episodes developing within 24 hours of administration of the first dose have not been reported in this species with the use of therapeutic doses. Therefore, appropriate precautionary steps should be taken, even when the drug is being administered intermittently.

Lymphoma involving large granular lymphocytes in cats: 11 cases (1982-1991).

Medical records of 11 cats with lymphoma involving large granular lymphocytes were reviewed. All 9 cats tested were FeLV-negative. Ten cats had a history of anorexia, lethargy, vomiting, or diarrhea, and had lymphoma involving abdominal viscera. The most common site of tumor in these cats was the jejunum. One cat had cutaneous masses caused by dermal and epidermal infiltration with neoplastic large granular lymphocytes. The most common hematologic abnormality was leukocytosis, characterized by neutrophilia with a left shift (7 cats); 2 cats had a left shift without neutrophilia. None of the cats had lymphocytosis, but immature large granular lymphocytes were found in the blood of 4 cats. The most common serum biochemical abnormalities were hypoalbuminemia (10 cats), hypocalcemia (10 cats), hypoproteinemia (9 cats), high aspartate transaminase activity (9 cats), and hyperbilirubinemia (8 cats). Large granular lymphocytes were characterized by abundant cytoplasm containing distinct azurophilic granules that varied in size and number. The most common cytochemical staining pattern included detection of alpha-naphthyl butyrate esterase, acid phosphatase, and beta-glucuronidase activities. On examination of histologic sections, granules stained weakly eosinophilic with Giemsa and moderately with periodic acid-Schiff reaction. Ultrastructurally, the granules appeared membrane bound and contained an electron-dense matrix in 4 cats.