Advanced diagnostic approaches and current medical management of insulinomas and adrenocortical disease in ferrets (Mustela putorius furo)

Understanding the histology and hematobiochemical aspects of Kadaknath an Indian black fowl with an appealing taste native to Dhar district Madhya Pradesh

1. The Kadaknath, an Indian fowl, is popular for its taste and health benefits. However, there is scarcity of information on its histology, haematology and biochemistry.2. Histology was conducted on various organs, including brain, heart, intestine, liver, kidney and the lung. For haematology investigation Mispa Count Plus was used (AGAPPE Diagnostic, India).3. Biochemical analysis involved determination of blood sugar, serum creatinine, serum urea, serum bilirubin, SGPT, serum protein and the alkaline phosphatase. The organs contained significant amounts of proteins characterised by strong amide (amide I-β-sheet) bands within mid and NIR region.4. Hydrated fatty acids were not found in mid IR region, although NIR revealed traces substantiated by strong - OH bending within 10 680/cm -10 400/cm.5. This work reported the usefulness of attenuated total reflectance (ATR) in understanding nutritive benefits of Kadaknath chickens and can assist avian practitioners in the detection of infections or pathological conditions.

New Insight on Insulinoma Treatment in a Pet Rat-A Case Report

Simple Summary

Insulinomas are tumors of the pancreas that cause hypoglycemia. They have high prevalence in ferrets, whereas in rats are a much rare finding. The available literature on spontaneous insulinomas in rats is currently scarce. The patient from our case report was presented with no obvious hypoglycemic signs, only progressive weakness of the hind limbs was noted. However, a blood exam revealed low blood glucose and a mass in the pancreas was found on the abdominal ultrasound. The patient responded well to treatment with oral dexamethasone and survived nearly 4 months in good general condition. In geriatric rats peripheral neuropathy and pituitary tumors are very common, leading to mobility disfunction. That is why insulinoma should always be considered in cases of neurological deficits in these patients.

Abstract

Insulinomas are insulin-producing tumors of pancreatic beta cells that cause hypoglycemia. They are extremely common in ferrets but have also been reported in guinea pigs and rats. This is a case report of an older rat with spontaneous insulinoma, which was confirmed by histopathology. The patient was presented at a regular check-up due to a chronic respiratory disease. The owner noticed progressive weakness of the hind limbs, which is quite commonly seen in older rats. A blood exam revealed hypoglycemia, which could have been associated with paraparesis. The patient responded to treatment with oral dexamethasone and was regularly monitored. It survived nearly 4 months in good general condition. The rat finally died most probably due to severe hypoglycemia caused by progression of the pancreatic tumor. This is the first report of a pet rat with insulinoma that was successfully treated with glucocorticoids.

Endocrine Diagnostics for Exotic Animals

Endocrine disease in exotic species is less common than in small animals. Nevertheless, the diagnostic principles used in small animals can be adapted to evaluate endocrine disease in many of the exotic species although species-specific aspects need to be considered. This article covers important diseases such as thyroid dysfunction in reptiles and birds, hyperthyroidism in guinea pigs, and hyperadrenocorticism in ferrets. Glucose metabolism in neoplasms affecting normal physiology, such as insulinoma in ferrets and gastric neuroendocrine carcinoma in bearded dragons, is discussed. Calcium abnormalities, including metabolic bone disease in reptiles and hypocalcemia in birds, are also covered.

Development of renal adenocarcinoma in a ferret with renal cortical cysts (Mustela putorius furo)

CASE DESCRIPTION

A 5.5-year-old 0.929-kg spayed female domestic ferret (Mustela putorius furo) underwent serial abdominal ultrasonographic and clinicopathologic examinations after multiple renal cysts were detected bilaterally during a routine examination.

CLINICAL FINDINGS

The ferret was apparently healthy at the start of the monitoring period and had no clinical signs for > 20 months. Four months after the initial examination, the largest cyst became increasingly mineralized; 17 months after detection, it had increased in size and become amorphous, and the ferret's plasma BUN concentration was mildly high. Within 21 months after the first visit, a nodule was detectable, and hydronephrosis developed in the kidney with the largest cyst. Findings for fine-needle aspirates from the nodule were consistent with renal carcinoma.

TREATMENT AND OUTCOME

Contrast-enhanced CT revealed severe unilateral nephromegaly with no contrast uptake in the affected ureter. Following surgical removal of the affected kidney, histologic examination identified renal adenocarcinoma replacing the entire renal cortex and medulla. The ferret was euthanized postoperatively because of declining condition. On necropsy, metastasis to a mesenteric lymph node was identified; comorbidities included 2 other neoplasms and acute, severe injury of the contralateral kidney.

CLINICAL RELEVANCE

Neoplastic transformation of a renal cyst was suspected in the ferret of this report on the basis of observed ultrasonographic changes over time and extensive infiltration of the neoplasm throughout the affected kidney. Renal cysts are linked to renal neoplasia in other species, and the findings for this patient supported the need for periodic monitoring of renal cysts in ferrets.

Nutrition for Pocket Pets (Ferrets, Rabbits, and Rodents)

Although the companion animal population is predominantly canine and feline, the popularity of domesticated small mammals (or pocket pets) has been steadily increasing. As a result, ferrets, rabbits, and rodents can be expected to present for veterinary evaluation. Many common medical problems in pocket pets are often associated with poor husbandry and/or inappropriate nutrition and are thus responsive to nutritional therapies. Although this article touches on minor background information and husbandry, the primary foci are the basic nutritional needs of, and common nutrition-responsive diseases in, pocket pets. Detailed husbandry needs are beyond the scope of this article.

Stress as cause of signs and symptoms of pseudo-Cushing's syndrome in buffy-tufted marmosets (Callithrix aurita)

Hyperadrenocorticism is a medical condition caused by the increase in cortisol production by the cortex of the adrenal gland. Although infrequently described in most animal species, its naturally occurring form, called Cushing's syndrome, is the most prevalent endocrinopathy in dogs. Cushing's syndrome is also present in humans and might be confused with the pseudo-Cushing's syndrome (PCS), rarely described in animals. PCS shares many of the clinical and biochemical features of Cushing's syndrome. However, the hypercortisolemia seen is usually idiopathic and, in some circumstances, associated with psychological disruptions. This report describes PCS-like disorder in two marmosets Callithrix aurita that were exposed to environmental changes, suggesting stress as the main cause of the process and reviewing the mechanisms involved in the pathogeny of the two syndromes.

Treatment and follow-up of a domestic ferret (Mustela putorius furo) with clinical leishmaniosis caused by Leishmania infantum

Leishmania infantum infection including treatment and follow up in domestic animals other than dogs and cats has not been described at this moment. This article describes the anti-Leishmania treatment and follow-up of a ferret (Mustela putorius furo) with leishmaniosis. A combined therapeutic protocol established for the patient, not yet approved for ferrets, was a combination of meglumine antimoniate plus allopurinol. A follow-up was established monthly during the first year in order to monitor the health condition of the patient. Six months after commencing allopurinol therapy, xanthine crystalluria was observed in urine sediment with no other urine alterations detected by urine analysis. The ferret worsened progressively with diarrhoea and weight loss after cohabiting with another ferret diagnosed with cryptosporidiosis. Cryptosporidium parvum was isolated in faecal samples from the patient detected by three different methods including Ziehl-Neelsen staining, a qualitative test to detection of C. parvum antigens and finally a specific molecular analysis to characterize the species. To the best of the authors´ knowledge, this is the first report providing information about anti-Leishmania protocol therapy used and follow-up in a domestic ferret with clinical leishmaniosis. Veterinarians practicing in endemic areas should be aware of this infection in ferrets at risk and their susceptibility especially when immunosuppressive conditions are present.

Paraplegia in a Domestic Ferret (Mustela Putorius Furo) Secondary to Metastatic Adrenocortical Carcinoma with Myxoid Differentiation

Neurologic disease is a common presentation of domestic ferrets (Mustela putorius furo) with infectious, neoplastic, and traumatic etiologies documented. Adrenocortical neoplasia is also well documented in domestic ferrets, with metastatic lesions rarely described. This case report describes an abnormal presentation of adrenocortical adenocarcinoma with myxoid differentiation and subsequent metastasis to the spinal cord and vertebral bodies, resulting in hind limb paraplegia in an adult spayed female ferret.

Dermatophytic pseudomycetomas in two ferrets (Mustela putorius furo)

BACKGROUND

Dermatophytic pseudomycetoma is an atypical form of dermatophytosis where the infection is located in the deep dermal and subcutaneous tissues. Although rare, it is most commonly associated with Microsporum canis or Trichophyton sp. It has been reported in cats, dogs and horses.

OBJECTIVES

To describe the clinical and pathological findings of dermatophytic pseudomycetoma caused by M. canis and Trichophyton sp. in two domestic ferrets.

ANIMALS

Two pet ferrets (Mustela putorius furo).

METHOD AND MATERIALS

Case report.

RESULTS

Two ferrets were diagnosed with dermatophytic pseudomycetoma confirmed by histological examination of tissue and fungal culture. In both cases, ferrets presented with several cutaneous firm nodules 0.6-3 cm in diameter. Microscopic lesions revealed multifocal nodular pyogranulomatous inflammation with intralesional fungi.

CONCLUSIONS AND CLINICAL IMPORTANCE

To the best of the authors' knowledge, this is the first description of dermatophytic pseudomycetoma in domestic ferrets. This disease should be included in the differential diagnosis of nodular dermatopathies in this species.

Characterisation of the French ferret population, husbandry, reported medical care and feeding habits

Ferrets have become a common companion animal. But no data are available on the French population of ferrets. The goal of the survey was to characterise this population, including demographic characteristics, husbandry, reported medical care and feeding habits. Complete data were available for 1205 pet ferrets in 709 households. Most ferrets (86·1 %) lived indoors, 1 % received only artificial lighting, and 47 % chewed their cage. For 60 % of the ferrets, body weight was higher in winter and lower in summer. Neutered ferrets (58·5 % of males and 62·9 % of females) appeared lighter than intact ferrets of comparable age. A majority (52·4 %) of ferrets received a mix of commercial foods and fresh foods, but 28·6 % were offered no commercial foods. Data were analysed using several multivariable logistic regression models including age, sex, castration, food type and artificial lighting developed for four clinical outcome (lethargy and/or insulinoma, dental problems, diarrhoea and/or bird-seed stools and alopecia). Predictors of four clinical outcomes (lethargy, dental disease, diarrhoea and alopecia) were examined using multivariable logistic regression, with age, sex, neuter status, food type and artificial lighting as the exposure variables. Aged ferrets were more likely to have lethargy, insulinoma, dental problems and alopecia. Ferrets with artificial lighting were more likely to show alopecia. Additionally, ferrets fed commercial food only or a mixed diet (both commercial food and fresh food) were more likely to have lethargy, insulinoma, dental problems, diarrhoea and/or bird-seed stools compared with ferrets fed fresh food only. We also found a significant association between neutering and alopecia. It is to our knowledge the first description of the French population of the ferret as a companion animal.

Reproductive Medicine in Ferrets

In the United States, desexing is performed routinely in ferrets at the age of 6 weeks, therefore reproductive tract diseases are not so common. However, in Europe most ferrets are desexed when they are several months old, or they are kept as intact animals. For this reason, diseases of the reproductive organs and a prolonged estrus are far more frequent in Europe than in the United States. This article summarizes and reviews the anatomy, reproductive physiology, management of reproduction (including surgical and hormonal contraception) and reproductive tract diseases in male and female ferrets.

Principles and Applications of Medical Oncology in Exotic Animals

Diagnoses of neoplasia in exotic animals have historically been made at death or just before euthanasia. Routine physical examinations are enabling early diagnosis while accessibility and affordability of advanced diagnostics are improving. With increasing expectations for care, treatment options are more frequently explored. Numerous oncologic medications have been adopted from human and small animal medicine and successfully used in exotic animals. Although there is a need for extended research, this article evaluates which medications have been used thus far for treatment protocols in zoologic and exotic animal species.

Ferret Oncology: Diseases, Diagnostics, and Therapeutics

Neoplastic disease is common in ferrets. Approximately half of all tumors diagnosed in ferrets are located in the endocrine or hemolymphatic system. Many factors may influence the choice of treatment. Medical management of adrenal tumors has a greater disease-free period compared to adrenalectomy. In ferrets with an insulinoma, no difference is seen in the mean survival time of medically and surgically treated patients. Aside from medical and surgical treatment modalities, chemotherapy and radiation therapy have also been described in ferrets in other types of tumors. The outcome of these treatment modalities is not always favorable.

Constant rate infusion of glucagon as an emergency treatment for hypoglycemia in a domestic ferret (Mustela putorius furo)

CASE DESCRIPTION

A 3-year-old female domestic ferret (Mustela putorius furo) with an insulinoma was treated because of a hypoglycemic crisis prior to scheduled pancreatectomy with concurrent nodulectomy.

CLINICAL FINDINGS

Previously, the ferret had clinical signs of lethargy and hind limb weakness; at that time, blood glucose concentration was low, and a tentative diagnosis (subsequently confirmed) of insulinoma was made. Prednisolone treatment (0.3 mg/kg [0.14 mg/lb], PO, q 12 h) did not improve clinical signs; the dosage was gradually increased over a 1-month course (1.8 mg/kg [0.82 mg/lb], PO, q 12 h) and maintained for 10 days. Overall, the treatment was ineffective, and the ferret remained lethargic and developed inappetence. At a reevaluation, the ferret had severe weakness and nonresponsiveness nearing a comatose state. Standard treatment with dextrose (1 mL of 50% solution, IV), and dexamethasone (1 mg/kg [0.45 mg/lb], SC) was administered with resultant improvement in mentation. The ferret was discharged from the hospital and then returned 3 days later for stabilization prior to pancreatectomy with concurrent nodulectomy.

TREATMENT AND OUTCOME

The day before surgery, the ferret was administered a glucagon constant rate infusion at a rate of 15 ng/kg/min (6.8 ng/lb/min), which resulted in an increase in blood glucose concentration to a euglycemic state and resolution of clinical signs of hypoglycemia.

CLINICAL RELEVANCE

As illustrated by the case described in this report, a glucagon constant rate infusion can be used successfully for the emergency treatment of hyperinsulinemic-hypoglycemic crisis in insulinomic ferrets.

Ferret nutrition

The domestic ferret (Mustela putorious furo) is a strict carnivore, also referred to as an obligate carnivore. Its dentition and gastrointestinal tract are adapted to a carnivorous diet. Its ancestor, the European polecat (Mustela putorius), feeds on birds and other small vertebrates. Domesticated ferrets have been fed mink feeds, cat foods, and now mostly subsist on commercial ferret diets formulated specifically to meet their needs.

Insulin dysregulation

Abnormalities of insulin metabolism include hyperinsulinaemia and insulin resistance, and these problems are collectively referred to as insulin dysregulation in this review. Insulin dysregulation is a key component of equine metabolic syndrome: a collection of endocrine and metabolic abnormalities associated with the development of laminitis in horses, ponies and donkeys. Insulin dysregulation can also accompany prematurity and systemic illness in foals. Causes of insulin resistance are discussed, including pathological conditions of obesity, systemic inflammation and pituitary pars intermedia dysfunction, as well as the physiological responses to stress and pregnancy. Most of the discussion of insulin dysregulation to date has focused on insulin resistance, but there is increasing interest in hyperinsulinaemia itself and insulin responses to feeding. An oral sugar test or in-feed oral glucose tolerance test can be performed to assess insulin responses to dietary carbohydrates, and these tests are now recommended for use in clinical practice. Incretin hormones are likely to play an important role in postprandial hyperinsulinaemia and are the subject of current research. Insulin resistance exacerbates hyperinsulinaemia, and insulin sensitivity can be measured by performing a combined glucose-insulin test or i.v. insulin tolerance test. In both of these tests, exogenous insulin is administered and the rate of glucose uptake into tissues measured. Diagnosis and management of hyperinsulinaemia is recommended to reduce the risk of laminitis. The term insulin dysregulation is introduced here to refer collectively to excessive insulin responses to sugars, fasting hyperinsulinaemia and insulin resistance, which are all components of equine metabolic syndrome.

Evaluation of portable blood glucose meters for measurement of blood glucose concentration in ferrets (Mustela putorius furo)

OBJECTIVE

To evaluate agreement of 3 models of portable blood glucose meters (PBGMs; 2 designed for use with human samples and 1 designed for veterinary use) with a laboratory analyzer for measurement of blood glucose concentrations in ferrets (Mustela putorius furo).

DESIGN

Evaluation study.

ANIMALS

52 ferrets.

PROCEDURES

Samples were analyzed with 4 PBGMs (whole blood) and a laboratory analyzer (plasma). Two PBGMs of the model designed for veterinary use were tested; each was set to a code corresponding to canine or feline sample analysis throughout the study. Agreement and bias between measurements obtained with the PBGMs and the laboratory analyzer were assessed with Bland-Altman plots. Linear regression analysis was performed to evaluate associations with venipuncture site by comparison of central (jugular) and peripheral (lateral saphenous or cephalic) venous blood samples.

RESULTS

Plasma glucose concentrations measured with the laboratory analyzer ranged from 41 to 160 mg/dL. Results from the PBGM for veterinary use coded to test a canine blood sample had the greatest agreement with the laboratory analyzer (mean bias, 1.9 mg/dL); all other PBGMs significantly underestimated blood glucose concentrations. A PBGM designed for use with human samples had the least agreement with the laboratory analyzer (mean bias, -34.0 mg/dL). Blood glucose concentration was not significantly different between central and peripheral venous blood samples for any analyzer used.

CONCLUSIONS AND CLINICAL RELEVANCE

Significant underestimation of blood glucose concentrations as detected for 3 of the 4 PBGMs used in the study could have a substantial impact on clinical decision making. Verification of blood glucose concentrations in ferrets with a laboratory analyzer is highly recommended.

Selected emerging diseases in ferrets

Since their introduction as pets several decades ago, ferrets have become an increasingly popular household pet. Great strides have been made in improving their diet and understanding common diseases (eg, insulinoma, hyperadrenocorticism, lymphoma) that affect them. With the frequency with which these conditions are seen, it sometimes is easy to forget that ferrets can be affected by other diseases. Some of these diseases, such as cryptococcosis, are known, but may be increasing in incidence and range, whereas others, such as hypothyroidism and pure red cell aplasia, may be underrecognized or underreported. This review highlights new and emerging diseases not already well reviewed in the literature.