Squamous cell carcinoma associated with a periorbital mass in a veiled chameleon (Chamaeleo calyptratus)

This report describes a squamous cell carcinoma in a 1-year-old female veiled chameleon (Chamaeleo calyptratus). The lesion developed as a small (1 by 1 mm) left periocular discoloration of a scale never involving the eye. The mass was first diagnosed as an abscess, increased in size (4 by 8 by 3 mm), and recurred after two surgical resections combined with antibiotic therapy. Poor nutritional condition and egg production by the chameleon complicated management of this condition. The mass was removed surgically a third time at which point histopathologic evaluation revealed a locally invasive squamous cell carcinoma. Bacterial culture of the mass isolated a pure culture of Pseudomonas aeruginosa. Ceftazidime was administered at 20 mg/kg IM every 48 h for 20 days. The animal died 3 months later from complications during an ovariohysterectomy for pregnancy toxemia and oviduct inertia. Necropsy showed no local recurrence or metastasis of the tumor.     

Quantitation of reticulated platelets in healthy dogs and in nonthrombocytopenic dogs with clinical disease

Background — Thrombocytopenia is a common disorder in dogs and development of an objective diagnostic assay to measure platelets newly released from bone marrow into the blood would provide a noninvasive way to predict megakaryocytopoiesis. Reticulated platelets are newly released platelets with increased concentrations of RNA that can be detected by flow cytometric analysis of blood stained with thiazole orange (TO).
Objectives — The goals of this study were to establish a reproducible method to quantitate reticulated platelets in dogs, to establish a reference interval for reticulated platelet percentages in healthy dogs, and to determine whether the percentage of reticulated platelets was nonspecifically increased in nonthrombocytopenic dogs with clinical disease.
Methods — Blood samples were obtained from healthy dogs and from nonthrombocytopenic dogs presented for a variety of disorders. An aliquot of whole blood was stained with TO and a phycoerythrin-labeled monoclonal antibody to platelet CD61, then analyzed by flow cytometry.
Results — The coefficients of variation were 7.8% to 15.6% (intra-assay precision) and 6.1% to 19.5% (interassay precision). Overnight storage for 18 to 26 hours, under variable conditions, resulted in an increase in the percentage of platelets staining with TO. The reference interval for reticulated platelets in the healthy control group was 0–4.3% (0–12,095/μL). No significant differences were found in the mean percentage of reticulated platelets or absolute concentration of reticulated platelets between control and affected dogs.
Conclusions — These studies demonstrate a reliable, noninvasive diagnostic assay for measurement of reticulated platelets in whole blood and provide a baseline for assessment of the clinical utility of the assay.     

The effect of long-acting injectable selenium formulations on blood and liver selenium concentrations and liveweights of red deer (Cervus elaphus)

AIM: To evaluate the efficacy of a new long acting injectable selenium ( Se ) formulation to increase the Se status and prevent Se deficiency in red deer. METHODS: Groups of weaned red deer (four stags and six hinds/group) grazing pastures containing <30 mg Se/kg DM were injected subcutaneously with either 0.5, 1.0 or 2.0 mg Se/kg as a new formulation of BaSeO4 (Deposel Multidose), 1.0mgSe/kg of a current formulation (Deposel), or not treated. Blood Se concentrations and liveweight were measured nine times at intervals over 377 and 270 days, respectively. RESULTS: Both formulations of Se elevated blood Se concentrations from 105 nmol/l pre-injection for at least 377 days with peak levels of 1894, 1395 and 818 nmol/l for high, medium and low doses of Deposel Multidose, respectively, at 73141 days, and 1508 nmol/l at 73-141 days for the medium dose of Deposel, which persisted at similar levels for the duration of the study. Deposel Multidose produced fewer and less severe subcutaneous tissue reactions than Deposel. Pastures contained 10 to 30 mg Se/kg DM. There was no significant difference in growth rate between treated and control deer. There was a significant (p<0. 01) linear relationship (y = 1.25x + 71.6, R2=0.86) between blood (x) and liver (y) Se concentrations in the range of 120 - 2100 nmol/l for blood concentrations, and 200 - 3000 nmol/kg for liver concentrations. CONCLUSION: Injections of BaSeO4 in both formulations studied were effective in increasing the Se status of deer but the new formulation produced fewer and less-severe tissue reactions. Young growing red deer appear less sensitive to Se deficiency as measured by weight gain, than sheep and cattle, suggesting that reference ranges for those species are not appropriate for deer. There was a linear correlation between blood and liver selenium concentrations.     

Isolation of oral spirochetes from dogs and cats and provisional identification using polymerase chain reaction (PCR) analysis specific for human plaque Treponema spp

Identification of plaque spirochetes from dogs is rare and no studies to date report cultivation of canine or feline plaque spirochetes. Plaque samples obtained from canine and feline patients were cultured in broth media. Spirochetes cultured were subjected to microscopic evaluation and were cloned on a solid medium. The clones were provisionally identified using species-specific PCR for treponema isolated from human plaque. Canine spirochete clones included Treponema denticola, T. socranskii ssp., T. vincentii, T. maltophilum, T. medium, and T. pectinovorum. Feline clones included T. maltophilum and T. socranskii. Non-amplified clones may represent novel treponemes. Future studies will be aimed at comparison of the spirochetes present in dogs and cats with or without periodontal disease.     

Efficacy and safety of selamectin against fleas and heartworms in dogs and cats presented as veterinary patients in North America

A series of randomized, controlled, masked field studies was conducted to assess the efficacy and safety of selamectin in the treatment of flea infestations on dogs and cats, and in the prevention of heartworm infection in dogs. In addition, observations were made on the beneficial effect of selamectin treatment on dogs and cats showing signs of flea allergy dermatitis (FAD). In all studies selamectin was applied topically, once per month, in unit doses providing a minimum dosage of 6mgkg(-1). Dogs and cats with naturally occurring flea infestations, some of which also had signs associated with FAD, were assigned randomly to receive three months of topical treatment with selamectin (220 dogs, 189 cats) or a positive-control product (dogs: fenthion, n=81; cats: pyrethrins, n=66). Selamectin was administered on days 0, 30, and 60. Day 0 was defined as the day that the animal first received treatment. Flea burdens were assessed by flea comb counts and clinical evaluations of FAD were performed before treatment, and on days 14, 30, 60, and 90. On days 30, 60, and 90, mean flea counts in selamectin-treated dogs were reduced by 92.1, 99.0, and 99.8%, and mean flea counts in fenthion-treated dogs were reduced by 81.5, 86.8, and 86.1%, respectively, compared with day 0 counts. Also, on days 30, 60, and 90, mean flea counts in selamectin-treated cats were reduced by 92.5, 98.3, and 99.3%, and mean flea counts in pyrethrin-treated cats were reduced by 66.4, 73.9, and 81.3%, respectively, compared with day 0 counts. Selamectin also was beneficial in alleviating signs in dogs and cats diagnosed clinically with FAD. A total of 397 dogs free of adult heartworm infection from four heartworm-endemic areas of the USA were allocated randomly to six months of treatment with selamectin (n=298) or ivermectin (n=99). Selamectin achieved a heartworm prevention rate of 100%, with all dogs testing negative for microfilariae and adult heartworm antigen on days 180 and 300. Selamectin was administered to a total of 673 dogs and 347 cats having an age range of 6 weeks to 19 years (3954 doses). The animals included 19 purebred or crossbred Collies (Bearded, Border, and unspecified). There were no serious adverse events. Results of these studies indicated that selamectin was highly effective in the control of flea infestations in dogs and cats without the need for simultaneous treatment of the environment or of in-contact animals and also was beneficial in alleviating signs associated with FAD. Selamectin also was 100% effective in preventing the development of canine heartworms and was safe for topical use in dogs and cats.     

Prevention of experimentally induced heartworm (Dirofilaria immitis) infections in dogs and cats with a single topical application of selamectin

In a series of six controlled studies (four in dogs, two in cats), heartworm-free dogs and cats were inoculated with Dirofilaria immitis larvae (L(3)) prior to topical treatment with the novel avermectin selamectin or a negative control containing inert formulation ingredients (vehicle). Selamectin and negative-control treatments were administered topically to the skin at the base of the neck in front of the scapulae. In dogs, selamectin was applied topically at dosages of 3 or 6mgkg(-1) at 30 days post-inoculation (PI), or of 3 or 6mgkg(-1) at 45 days PI, or of 6mgkg(-1) at 60 days PI. Cats were treated topically with unit doses providing a minimum dosage of 6mgkg(-1) selamectin at 30 days PI. Of the animals that were treated 30 days PI, some dogs were bathed with water or shampoo between 2 and 96h after treatment, and some cats were bathed with shampoo at 24h after treatment. Between 140 and 199 days PI, the animals were euthanized and examined for adult D. immitis. Adult heartworms developed in all control dogs (geometric mean count, 18.7 worms) and in 88% of control cats (geometric mean count, 2.1 worms). Selamectin was 100% effective in preventing heartworm development in dogs when administered as a single topical dose of 3 or 6mgkg(-1) at 30 days after infection, 3 or 6mgkg(-1) at 45 days after infection, or 6mgkg(-1) at 60 days after infection. Selamectin was 100% effective against heartworm infections in cats when administered as a single topical unit dose of 6mgkg(-1). Bathing with water or shampoo between 2 and 96h after treatment did not reduce the efficacy of selamectin as a heartworm prophylactic in dogs. Likewise, bathing with shampoo at 24h after treatment did not reduce the efficacy of selamectin in cats. These studies demonstrated that, at the recommended dosage and treatment interval, a single topical administration of selamectin was 100% effective in preventing the development of D. immitis in dogs and cats.     

Efficacy and safety of selamectin against gastrointestinal nematodes in cats presented as veterinary patients

A series of randomized, controlled, masked, field (veterinary patient) studies were conducted in the USA and Europe to evaluate the efficacy of selamectin, a novel macrocyclic lactone of the avermectin subclass, in the treatment of naturally acquired gastrointestinal nematode infections in cats. After confirmation of ascarid and/or hookworm infection, 298 cats of various ages and breeds were randomly assigned to treatment with selamectin (n=202) or an existing commercially approved positive-control product (n=96). Unit doses of selamectin (providing a minimum dosage of 6mgkg(-1)) were administered topically to the skin in a single spot at monthly intervals. Quantitative fecal examinations were performed on days 0 (before treatment), 30, and 60. In the selamectin-treated cats, fecal ascarid egg counts were reduced by 99.6 to 100% on day 30, and by 99.9 to 100% on day 60. Fecal hookworm egg counts were reduced by 98.3% on day 30, and by 100% on day 60 in the selamectin-treated cats. The positive-control products achieved reductions in egg counts of 96.5 to 100% (ascarids) and 98.9 to 99.9% (hookworms). These studies have shown that monthly topical administration of selamectin is safe and highly effective in the treatment of naturally acquired ascarid and hookworm infections in cats.     

Contemporary issues of veterinary practice valuation and sale transactions.

This article comprises discussions on practices with little or no salable value, the determination and measurement of the value of a veterinary practice, the evolution of the small animal practice marketplace, the costs of selling a portion of a practice, lack of marketability discount, and C corporation issues.     

Preliminary observations of genetic susceptibility of elk (Cervus elaphus nelsoni) to chronic wasting disease by experimental oral inoculation.

To compare the genetic susceptibility of elk (Cervus elaphus nelsoni) with various alleles of the PRNP gene, which encodes the normal cellular prion protein, to chronic wasting disease (CWD), eight 8-month-old elk calves of 3 genotypes (2 132MM, 2 132LM, and 4 132LL) were orally dosed with CWD-infected brain material from elk. During postinoculation (PI) month 23, both 132MM elk had lost appetite, developed clinical signs of weight loss and central nervous system (CNS) dysfunction, and were euthanized. Two other elk (both 132LM) developed similar clinical signs of disease and were euthanized during PI month 40. All 4 affected elk had microscopic lesions of spongiform encephalopathy (SE), and PrPres, the disease-associated form of the prion protein, was detected in their CNS and lymphoid tissues by use of immunohistochemical (IHC) and Western blot (WB) techniques. These findings indicate that elk with MM and LM at codon 132 are susceptible to orally inoculated CWD. All 4 LL elk are alive at PI year 4 and are clinically normal, which suggests that 132LL elk may have reduced susceptibility to oral infection with CWD-infected material or may have prolonged incubation time.