Studies on the mechanism of polyuria induced by cortisol excess in the dog

Summary

Water balance studies were performed in 7 experimental dogs before and during a period of cortisol‐induced polyuria and in one dog with spontaneous hyperadrenocorticism before and after removal of an adrenocortical carcinoma. Measurements of urine and plasma osmolality and plasma arginine vasopressin concentration were made at regular intervals during the water deprivation studies. The results indicate that cortisol does not block the release of vasopressin but interferes with its action in the kidney.     

Myxedema coma leading to respiratory depression in a dog

A 10-year-old, intact male, cocker spaniel was presented with hypothermia, without shivering, and progressive stupor leading to coma. Myxedema coma, potentially precipitated by diuretic therapy, was tentatively diagnosed and treatment initiated, but progressive respiratory depression led to the decision to euthanize. Postmortem findings supported the diagnosis of myxedema coma.     

Studies on the mechanism of polyuria induced by cortisol excess in the dog

Summary Water balance studies were performed in 7 experimental dogs before and during a period of cortisol-induced polyuria and in one dog with spontaneous hyperadrenocorticism before and after removal of an adrenocortical carcinoma. Measurements of urine and plasma osmolality and plasma arginine vasopressin concentration were made at regular intervals during the water deprivation studies. The results indicate that cortisol does not block the release of vasopressin but interferes with its action in the kidney.     

Severe polyuria and polydipsia as major clinical signs in a horse with unilateral renal adenocarcinoma

A 14‐year‐old Swiss Warmblood gelding was presented with chronic severe polyuria, polydipsia and weight loss. At the time of admission, water intake was 240 l/day. On rectal examination, a large mass was identified in the left dorsal abdominal quadrant, which was shown to originate from the left kidney by transabdominal ultrasonographic examination. Unilateral nephrectomy via flank incision was performed under general anaesthesia. Histopathological examination of the tumour revealed a papillary renal adenocarcinoma. Successful outcome and survival was documented 13 months after surgery. Severe polyuria and polydipsia should be considered as major clinical signs for renal carcinoma in horses, which can be successfully treated with unilateral nephrectomy if no signs of metastatic spread are evident.     

Clinical evaluation of metrizamide as a myelographic agent in the dog.

Metrizamide, a new, water-soluble contrast agent, was clinically evaluated as a myelographic agent in 17 dogs. Nine dogs were given lumbar subarachnoid injections and six were given cisternal injections. Two dogs were given cisternal and lumbar injections; in one dog, both injections were given on the same day. The dosage ranged from 0.3 to 0.57 ml/kg of body weight, using an isotonic solution of metrizamide. Of eight dogs given cisternal injections, two experienced convulsive activity requiring diazepam treatment during the anesthetic recovery period. The lumbar injections did not cause convulsions. Satisfactory radiographic density persisted up to 45 minutes after injection, allowing time for several views to be obtained. In general, metrizamide appeared to be an adequate myelographic agent in the dog.     

Fibrocartilaginous emboli as the cause of ischemic myelopathy in a dog.

Acute hemiplegia and Horner's syndrome developed in a 6-year-old female black Labrador Retriever 24 hours after a day of exercise. Radiographic, cerebrospinal fluid, and electromyographic studies did not detect the site or nature of the suspected cervical lesion. The dog showed no improvement after evaluation for 5 days on corticosteroid and antibiotic therapy. Gross and microscopic examination revealed the presence of an ischemic infarct in the C6 segment of the cervical spinal cord and associated fibrocartilaginous emboli. The nature of the clinical signs and the pathologic findings in this case are similar to previous reports of human and canine cases.     

Metastatic malignant pilomatrixoma,acanthomatous ameloblastoma,and liver tumor in a dog with polyphagia,polyuria, polydipsia,and weight loss

A 12-year-old, spayed female, Labrador dog was presented for evaluation of polyphagia, polyuria, polydipsia, weight loss of 2 months duration, and multiple cutaneous and subcutaneous masses. The dog was diagnosed with malignant pilomatrixoma with renal, lung, and lumbar metastases. This report describes an atypical presentation of malignant pilomatrixoma.     

Gastric torsion in the dog III. Fundic gastropexy as a relapse-preventing procedure

In 36 dogs having recovered after nonsurgically treated gastric torsion, fundic gastropexy, including cauterization of the fundic wall before suturing, was performed 1 week to 3–5 months after the initial attack. One of the animals died of intercurrent disease and one could not be traced. Within an observation time of 1–5 months to 4–5 years (mean 18 months), no relapse occurred in the remaining 34 animals operated upon.     

Protothecosis with ocular involvement in a dog.

An 8 1/2-year-old Collie dog was referred for evaluation of chronic diarrhea as well as sudden blindness and leukokoria of the right eye. An organism morphologically similar to Prototheca sp was recovered from the subretinal fluid and was found at necropsy in the eyes, gastrointestinal tract, lungs, lymph nodes, kidneys, heart, abdominal fat, and omentum.     

Acute myelomonocytic leukemia manifested as myelophthisic anemia in a dog.

A 10-year-old, Golden Retriever-type castrated male dog was found to have a hemogram consistent with myelophthisic anemia. Within 30 days the hemogram changed in such a manner that a myeloproliferative disorder was evident. On the basis of hematologic, cytochemical, and cytologic findings, acute myelomonocytic leukemia was diagnosed.     

Monoclonal cryoglobulinemia with macroglobulinemia in a dog.

A 9-year old female Doberman Pinscher had a 5-month history of epistaxis. On routine testing of the dog's serum, blockage of the intake tubes of the equipment resulted. At this point, cryoglobulinemia was suspected and was later confirmed to be due to a monoclonal cryoglobulin (IgM), by means of immunochemical studies. Clinical recovery was achieved by use of cytotoxic drugs.     

某警犬基地繁殖障碍的原因调查

为了解警犬繁殖障碍现状,分析其原因,作者于2007年对某警犬基地警犬繁殖障碍情况进行了调查,分析了发生原因,并提出了综合防制措施。     

Malignant histiocytosis in a Bernese mountain dog presenting as a mandibular mass.

A Bernese mountain dog was evaluated because of a gingival mass, multiple abdominal masses, and a pulmonary mass. Malignant histiocytosis was diagnosed based on cytological examination of splenic and bone marrow aspirates and histological examination of a bone marrow biopsy and the gingival mass. The case demonstrates that malignant histiocytosis is difficult to diagnose due to the variety of histiocytic disorders.     

The role of vasopressin in dogs with polyuria

Polyuria and polydipsia (PUPD) occur frequently in dogs and may be caused by a variety of endocrine, metabolic, and renal disturbances. The studies described in this PhD Thesis, which was defended in January 2004 in Utrecht, investigated the role of the antidiuretic hormone vasopressin (VP) in the pathogenesis of different forms of canine polyuria. Experiments in healthy dogs demonstrated that the ranges of urine specific gravity and urine osmolality are much larger than previously thought. A water deprivation test is not required in all polyuric dogs, because serial measurements of urine osmolality may already lead to the diagnosis of primary polydipsia, in some cases. In dogs with primary polydipsia a wide variation in VP responses to hypertonic stimulation can be found, including a hyperresponse, a hyporesponse, and a non-linear response. The significance of the VP response to hypertonic saline infusion as the 'gold standard' for a diagnosis of canine polyuria is discussed. In the dog, VP is secreted in a pulsatile fashion with a wide variation in the number of VP pulses, VP pulse duration, and VP pulse amplitude and height. The occurrence of spontaneous VP pulses may severely hamper the interpretation of the curve describing the relationship between plasma osmolality and plasma VP concentration during osmotic stimulation. A radioimmunoassay to measure the VP-dependent water channel aquaporin-2 (AQP2) in urine was developed in dogs. In healthy dogs, urinary AQP2 excretion closely reflects changes in collecting duct exposure to VP. Measurement of urinary AQP2 excretion in polyuric dogs may be helpful to distinguish between central diabetes insipidus, nephrogenic diabetes insipidus, and primary polydipsia.     

谈警犬训练中人的主导性

在警犬训练中,影响训练效果的因素很多,如受训犬的选择、训练的环境、气候、训练时机的选择等.业内有句话说:什么样的人带什么样的犬.作为警犬训练中的主导者和综合刺激者,其语言、动作、性格、经验都直接作用于犬,影响训练效果.     

Ketamine as a part of anaesthetic management in a dog with twiddler's syndrome

An 11‐year‐old male German shepherd dog was referred for possible pacemaker implantation. A routine 6‐lead electrocardiogram revealed a third‐degree atrio‐ventricular block with a heart rate of 40 to 45 beats/minute. A transvenous pacemaker implantation procedure was scheduled. The dog was premedicated with 10 µg/kg acepromazine and 5 mg/kg pethidine. A dose of 5 mg/kg ketamine and 0·2 mg/kg diazepam were used for induction and isoflurane in O₂ and a constant rate infusion of ketamine (20 to 30 µg/kg/minute) were administered for maintenance of general anaesthesia. Due to a twiddler's syndrome, the pacemaker had to be repositioned. For the second procedure, the same protocol was employed except for a lower dose of ketamine both for induction (3 mg/kg) and constant rate infusion (10 to 15 µg/kg/minute). Ketamine appeared to be useful for both management of anaesthesia and cardiac pacemaker implantation in the absence of a temporary pacemaker.