Dilated cardiomyopathy in juvenile Portuguese Water Dogs

Dilated cardiomyopathy recently has been recognized in juvenile Portuguese Water Dogs. The purpose of this study was to evaluate unaffected and affected puppies by physical examination, electrocardiogram (ECG), echocardiogram, specific biochemical assays, and ultrastructure to document disease progression and to develop a method of early detection. Results of segregation analysis were consistent with autosomal recessive inheritance. Of 124 puppies evaluated clinically and echocardiographically, 10 were affected. No significant differences were found between unaffected and affected puppies for blood and myocardial carnitine or taurine concentrations, serum chemical variables, results of ophthalmological examinations, ECGs, or measurement of urine metabolites. Ultrastructural examination of myocardium from affected dogs revealed myofibrillar atrophy and small regions of myofibrillar degeneration, most prominently at the region of the intercalated discs. Only echocardiography allowed detection of affected puppies before clinical signs became evident. Echocardiography revealed a significant difference in the shortening fraction, E point to septal separation, and the end systolic and diastolic left ventricular internal diameters. Affected puppies were detected 1-4 weeks before the development of acute congestive heart failure.     

Dimensions and histologic characteristics of the small intestine of dogs during postnatal development

OBJECTIVE: To quantify dimensions of the small intestine of dogs and describe changes in histologic characteristics of the mucosa during postnatal development. SAMPLE POPULATION: Gastrointestinal tract tissues obtained from 110 Beagles (15 adult females and 95 puppies of both sexes). PROCEDURE: Several variables (length, total weight, mucosal weight, and nominal surface area) of the small intestine were measured in puppies at birth but before suckling; 1 day after birth and subsequent suckling, 21, 42, and 63 days after birth, and in the adult dams of the puppies. Tissue structure was examined and quantified at each time point by use of routine histologic examination and ocular micrometry of formalin-fixed specimens stained with H&E. RESULTS: Small intestinal dimensions increased throughout development with the greatest proportional changes during the first day after birth and onset of suckling. Villus height decreased during suckling but had consistent values from 42 days after birth to maturity, whereas crypt depth increased from birth to maturity. Vacuolated enterocytes were evident from birth to 21 days but not thereafter. CONCLUSIONS AND CLINICAL RELEVANCE: Increases in intestinal dimensions provide growing dogs with a greater capacity for digestion and absorption. Changes in mucosal architecture and cell populations coincided with shifts in dietary inputs. These findings may assist in the diagnosis of small intestinal diseases and nutritional responses during growth and development of dogs.     

Cardiac involvement in canine babesiosis

Cardiac dysfunction in canine babesiosis has traditionally been regarded as a rare complication, with the majority of lesions reported as incidental findings at post-mortem examination. Recent studies have, however, demonstrated cardiac lesions in canine babesiosis. Cardiac troponins, especially troponin I, are sensitive markers of myocardial injury in canine babesiosis, and the magnitude of elevation of plasma troponin I concentrations appears to be proportional to the severity of the disease. ECG changes in babesiosis are similar to the pattern described for myocarditis and myocardial ischaemia and together with histopathological findings indicate that the heart suffers from the same pathological processes described in other organs in canine babesiosis, namely inflammation and hypoxia. The clinical application of the ECG appears to be limited and thus cardiovascular assessment should be based on functional monitoring rather than an ECG tracing. On cardiac histopathology from dogs that succumbed to babesiosis, haemorrhage, necrosis, inflammation and fibrin microthrombi in the myocardium were documented, all of which would have resulted in ECG changes and elevations in cardiac troponin. Myocardial damage causes left ventricular failure, which will result in hypotension and an expansion of the plasma volume due to homeostatic mechanisms.     

Audiograms estimated from brainstem tone-evoked potentials in dogs from 10 days to 1.5 months of age

The objective of this study was to build audiograms from thresholds of brainstem tone-evoked potentials in dogs and to evaluate age-related change of the audiogram in puppies. Results were obtained from 9 Beagle puppies 10-47 days of age. Vertex to mastoid brainstem auditory-evoked potentials in response to 5.1-millisecond Hanning-gated sine waves with frequencies octave-spaced from 0.5 to 32 kHz were recorded. Three dogs were examined at 10, 13, 19, 25, and 45 days. Four other dogs were examined at 16 days. Data from 7 dogs between 42 and 47 days of age were pooled to obtain audiogram reference values in 1.5-month-old puppies. The best auditory threshold lowered from above 60 dB sound pressure level (SPL) to values close to 0 dB SPL between 13 and 25 days of age and then stabilized. The audible frequency range widened, including 32 kHz in all tested dogs from the 19th day. In the 7 1.5-month-old puppies, the mean auditory threshold decreased by 11 dB per octave from 0.5 to 2 kHz. The auditory threshold was lowest and held the same value from 2 to 8 kHz. The mean auditory threshold increased by 20 dB per octave from 8 to 32 kHz. Near threshold, click-evoked potentials test only a small part of the audible frequency range in dogs. Use of tone-evoked potentials may become a powerful tool in investigating dogs with possible partial hearing loss, including during the auditory system maturation period.     

Cardiac conotruncal malformations in a family of beagle dogs

O bjectives : To study forms of congenital heart disease present in a family of beagle dogs with a strong prevalence of ventricular septal defect and to document the pathological findings associated with the ventricular septal defects and investigate the mode of transmission.
M ethods : The animals were investigated by physical examination, radiography, electrocardiography and ultrasonography to diagnose the presence of congenital heart disease. Some animals were diagnosed at post-mortem examination and the dead animals underwent post-mortem examination to verify the presence of ventricular septal defect. An analysis of pedigree was undertaken and two of the affected animals were mated to investigate the mode of transmission.
R esults : Among the 28 dogs evaluated clinically or by post-mortem examination, 14 cases of ventricular septal defect were identified. The post-mortem examination showed some abnormalities of the ventricular outflow region associated with malformation of conotruncal septum development. When two affected dogs were bred, congenital heart disease was present in all of the offspring.
C linical S ignificance : The congenital heart disease identified in this beagle family can be classified as conotruncal malformation, and an autosomal recessive mode of inheritance was suggested by pedigree analysis.     

Cachexia secondary to intracranial anaplastic (malignant) ependymoma in a boxer dog

An eight-year-old female boxer was referred because of weight loss of several months' duration. On physical examination, cachexia was the only reported abnormality. Neurological symptoms were shown only in the last days preceding death and consisted of altered mental status, compulsive behaviour and left rear proprioception deficit. At post-mortem examination, a voluminous, soft, haemorrhagic mass was found invading the floor of the brain. Based on the morphological features of the tumour, marked parenchymal invasion, extensive necrosis and cellular atypia, the mass was classified as an anaplastic ependymoma. This case report shows similarities to the diencephalic syndrome reported in human paediatric medicine in which the main clinical sign is a profound emaciation in spite of normal or slightly diminished caloric intake. Weight loss and cachexia are clinically relevant problems in small animals and these clinical signs should raise a suspicion, among the other differentials, of a brain tumour, even in absence of neurologic signs.     

Pulmonary oedema in Swedish hunting dogs

A syndrome of acute dyspnoea after hunting in 16 Swedish hunting dogs is characterised. Radiographic pulmonary infiltrates interpreted as pulmonary oedema were found in the acute stage. In 12 dogs, the infiltrates regressed after five to 14 days. Subendocardial necrosis and pulmonary oedema were found at postmortem examination in four other dogs with acute and recurrent dyspnoea after hunting, and myocardial fibrosis in a further three dogs with a history of recurrent dyspnoea after hunting; none of these pathological changes was seen in dogs which had no previous history of dyspnoea after hunting. A pathogenetic mechanism is proposed whereby high catecholamine levels, present during hunting due to the stress of excitement and exercise, cause acute cardiac and pulmonary lesions in some susceptible dogs, similar to neurogenic or postictal pulmonary oedema.     

PRENATAL SONOGRAPHIC DIAGNOSIS OF FETAL DEATH AND HYDRANENCEPHALY IN TWO CHIHUAHUA FETUSES

Hydranencephaly and fetal death was diagnosed in two of three fetuses during the abdominal sonographic examination of a 2.5-year-old, intact female Chihuahua that had clinical signs of dystocia 63 days after mating. A cesarean section was performed and one live normal puppy was present. Two dead puppies, each with a markedly enlarged and fluid filled skull were removed.     

Canine parvovirus enteritis 1: Clinical, haematological and pathological features of experimental infection

The effect of oral infection of puppies, eight and 10 weeks old, with canine parvovirus of faecal origin was studied. Clinical signs of enteric disease were first apparent at five days after inoculation and persisted during days 6 and 7 after inoculation. The severity of clinical signs varied from transient dullness and anorexia to emesis, dysentery and death. Changes in haematological parameters were first found at day 3 after inoculation when a relative lymphopenia was observed. A profound neutropenia developed in severely affected dogs after the appearance of clinical enteric disease. Post mortem examination revealed thymic atrophy in all dogs killed on day 4 after inoculation. Macroscopic changes in the small intestine were apparent only in animals examined during the phase of severe enteric disease and consisted of thickening, rigidity and congestion of the small intestines. Microscopically there was lymphocytolysis in the thymic cortex and the germinal centres of the lymph nodes from days 2 and 3 after inoculation respectively and this rapidly resulted in depletion of these tissues. There was repopulation of lymph nodes from day 7 after inoculation but significant thymic regeneration was not apparent during the course of this study. In the small intestine, necrosis of crypt epithelium, atrophy of villi and, in some areas, complete collapse of mucosal architecture were found but the extent of these changes varied along the length of the small intestine and between individuals. Regenerative intestinal changes were observed in those animals surviving the acute phase of enteric dysfunction. The variable severity of clinical and enteric lesions, together with the factors which may affect the expression of clinical disease, are discussed.     

Electrocardiographic changes and cardiac pathology in canine babesiosis

The main purpose of this study was to describe electrocardiographic (ECG) changes in canine babesiosis, and to relate these to clinical severity, outcome and cardiac pathology.Four groups of dogs with babesiosis were studied: mild to moderate anemia, severe anemia, concurrent autoagglutination and concurrent complications. Lead II ECG was recorded at admission for 1 minute in all dogs (121). A six lead ECG was recorded in 88 dogs. Full necropsy was performed on 16 dogs (5 died on arrival, 11 had ECG recording).The following ECG changes were recorded in relatively high prevalence: sinoatrial blocks or sinus arrest (7%), ventricular premature complexes (7%), low R-amplitude (23%), prominent Q (13%), axis deviations (40%), prolonged QRS (32%), ST depression and coving (28%), large T (42%), and notched R (28%). Differences between groups were minor. There was a significantly higher prevalence of sinus bradycardia and irregular rhythm in the non-survivors. Gross pathological changes were pericardial effusion and hemorrhages. Histological changes were hemorrhages, necrosis, inflammation and fibrin microthrombi. The only correlation between pathology and ECG was low R-amplitude and pericardial effusion.The ECG changes were similar to the pattern described for myocarditis and myocardial ischemia, and together with the histopathological findings indicated that the heart suffers from the same pathological processes described in other organs in canine babesiosis, namely inflammation and hypoxia. As the clinical application of the ECG changes found in this study was limited, cardiovascular assessment should be based on functional monitoring rather than ECG.     

Collie eye anomaly in the rough collie in Norway

The results of eye examinations of 741 rough collies for collie eye anomaly (CEA) are described. Of the examined dogs, 40-8 per cent had CEA, including, in most cases, chorioretinal dysplasia (CRD). 7-7 per cent had coloboma of the optic disc while 3–5 per cent had complications of CEA, either retinal detachment or intraocular bleeding. There was no sex difference nor was the frequency of the disease influenced by coat colour. After estimating the total frequencies of the different manifestations of the disease, the dogs were divided into two groups according to the age at first examination. In the group of dogs examined between seven weeks and three months old, 48-9 per cent had CEA, compared to a frequency of 25-6 per cent in the group of dogs examined after three months of age. All the puppies with coloboma also showed signs of CRD, while among the older dogs 11 of the 66 CEA cases reported showed signs of coloboma without CRD. Twenty-two dogs which had been examined as puppies and given the diagnosis CEA with minor chorioretinal changes were re-examined at an older age. Of these dogs, 15 had ophthalmoscopi-cally normal fundi at re-examination while seven were unchanged from the first examination.     

Serum cortisol and thyroxine concentrations as predictors of death in critically ill puppies with parvoviral diarrhea

OBJECTIVE: To evaluate the role of adrenal and thyroid hormones in the prediction of death in a population of critically ill puppies with parvoviral diarrhea by measuring serial daily serum concentrations of cortisol and thyroxine. DESIGN: Prospective case-control study. ANIMALS: 57 critically ill puppies with parvoviral diarrhea admitted to the hospital and 17 clinically normal control puppies. PROCEDURES: Basal serum cortisol and thyroxine concentrations were measured for each dog with parvoviral diarrhea at admission (prior to treatment) and daily until death, euthanasia, or discharge. RESULTS: Median time between admission and death was 48 hours (ie, on day 3). Median serum cortisol concentration on day 1 (admission) in all dogs with parvoviral diarrhea (248 nmol/L) was significantly higher than in control dogs (77 nmol/L). No significant difference was found in the day 1 median serum cortisol concentration of 11 dogs that died (302 nmol/L) and 46 dogs that survived (238 nmol/L). A significantly higher median serum cortisol concentration was, however, found in nonsurvivor group dogs, compared with survivor group dogs, on days 2 and 3. Median serum thyroxine concentration on day 1 in dogs with parvoviral diarrhea was significantly lower than in control dogs (8.12 nmol/L vs 35 nmol/L, respectively). Median serum thyroxine concentration of nonsurvivor group dogs (4.4 nmol/L) was significantly lower than that of survivor group dogs (9.2 nmol/L) at admission and became even lower on days 2 and 3. CONCLUSIONS AND CLINICAL RELEVANCE: High serum cortisol and low serum thyroxine concentrations at 24 and 48 hours after admission were associated with death in dogs with parvoviral diarrhea.     

Pulverulent nuclear cataract in the Norwegian buhund

Pulverulent cataracts were diagnosed in 52 of 102 Norwegian buhunds, with both sexes being equally affected. All the dogs were otherwise considered clinically healthy. Initial lens changes were visible from six and a half weeks of age as small dots parallel to the suture lines behind the nucleus. Gradually, the opacities along the suture lines became more opaque until, by the age of four to five and a half years, they had progressed to involve the fetal nucleus which then resembled a ball of candy floss. The outer part, the adult nucleus, usually remained clear, and the cortex was not involved. The ages of the dogs in the present study ranged from three and a half weeks to 12 years at first examination. An outcross of an affected bitch to a mixed-breed dog resulted in three puppies, of which two were affected. The retinas could be evaluated in all the examined dogs, and revealed no abnormalities except for one case of focal retinopathy. In addition to the pulverulent cataracts, 10 cases of cortical cataracts were diagnosed, three of which also had pulverulent cataracts. Based on the pedigrees, an autosomal dominant mode of inheritance with a high degree of penetrance is suggested for pulverulent cataract.     

Recurrent supraventricular arrhythmias in a dog with atrial myocarditis and gastritis

This report describes a dog with recurrent atrial fibrillation and atrial flutter associated with chronic gastritis. Although no underlying structural heart disease was apparent antemortem or on gross post-mortem examination, chronic atrial myocarditis was seen on histopathological examination. Atrial myocarditis is a recognised cause of atrial fibrillation in human beings with presumed lone fibrillation, and an association between supraventricular tachyarrhythmias and infectious agents has been made.     

An outbreak of septic endometritis in the Arctic blue fox (Alopex lagopus) caused by Clostridium carnis

An outbreak of endometritis and septicaemia in farms that raise Arctic blue foxes is described. Eleven animals from eight different farms were examined, most of them pregnant or with newly delivered litters. Pathological examination indicated inflammation of the uterus, and focal necrotic changes in the liver. In some animals evidence of hemorrhaging was found in the anterior part of the small intestine. Bacteriological examination revealed abundant growth from different organs of the animals of a pure culture of a small, slender, Gram-variable, sporeforming rod, which was identified phenotypically as aerotolerant Clostridium carnis. This identification was confirmed by DNA hybridization. The organism caused death in mice 1–2 days after intraperitoneal inoculation, and killed an Arctic blue fox which was inoculated intracervically. Two foxes, pretreated with diethyl-stilboestrol, became seriously ill after intrauterine inoculation, but survived. The spontaneous outbreak of the disease was characterized by sudden onset of septicaemia with few or no clinical symptoms before the animals succumbed.     

A cardiomyopathy in the English Cocker Spaniel: a clinico-pathological investigation

This report describes some of the characteristics of a cardiomyopathy in English Cocker Spaniels. Forty-nine dogs from a kennel with a history of a cardiomyopathy were assessed clinically, electrocardiographically and radiographically. Angiography, haemodynamic and post-mortem examinations were carried out on selected dogs. On electrocardiographic (ECG) and radiographic criteria the dogs were classified into five groups. Twenty-six dogs (Group 1) were normal. Seven dogs (Group 2) showed ECG changes compatible with left or biventricular hypertrophy in the absence of radiographic abnormality. This was interpreted as concentric hypertrophy. Seven dogs (Group 3) showed ECG and radiographic evidence of cardiac hypertrophy with five of the seven exhibiting enlargement of both chambers. The changes were considered to be compatible with eccentric hypertrophy. Post-mortem findings in dogs with ECG characteristics of Groups 2 and 3 have shown concentric hypertrophy in three cases and eccentric hypertrophy in one case. Six dogs (Group 4) had right axis deviations. Three dogs (Group 5) showed left axis deviations. It is suggested that a cardiomyopathy exists in English Cocker Spaniels initially developing as a concentric hypertrophy and progressing to eccentric hypertrophy. At present the aetiology is unknown.     

Colonization of neonatal puppies by staphylococci.

The composition of the normal staphylococcal flora of bitches and their litters held in a breeding unit was studied. The animals were sampled at a number of sites using moistened swabs. Six bitches were sampled daily, for 10 days, before whelping and then, together with four puppies per litter, at whelping (day 11) and at 1 and 7 days thereafter. Staphylococcus intermedius formed the predominant staphylococcal isolate. S. intermedius counts at the oral and nasal sites on the bitches did not change markedly before whelping and remained low (< 6 cfu/swab). Significant rises in the oral counts on both the bitches (P < 0.05) and puppies (P < 0.001) were then observed after whelping (days 11-18). Abdominal counts on both the bitches and puppies also rose (P < 0.001) after whelping. S. intermedius counts at the vaginal vestibulum of the pregnant bitches were found to be higher than at any other site sampled and did not alter markedly until whelping when a decrease (P = 0.05; days 10-12) was observed. S. intermedius was not found at the anal site in any of the six bitches and only transiently colonized five of the puppies.     

Maturation of the auditory system in clinically normal puppies as reflected by the brain stem auditory-evoked potential wave V latency-intensity curve and rarefaction-condensation differential potentials

OBJECTIVE: To evaluate auditory maturation in puppies. ANIMALS: Ten clinically normal Beagle puppies. PROCEDURE: Puppies were examined repeatedly from days 11 to 36 after birth (8 measurements). Click-evoked brain stem auditory-evoked potentials (BAEP) were obtained in response to rarefaction and condensation click stimuli from 90 dB normal hearing level to wave V threshold, using steps of 10 dB. Responses were added, providing an equivalent to alternate polarity clicks, and subtracted, providing the rarefaction-condensation differential potential (RCDP). Steps of 5 dB were used to determine thresholds of RCDP and wave V. Slope of the low-intensity segment of the wave V latency-intensity curve was calculated. The intensity range at which RCDP could not be recorded (ie, pre-RCDP range) was calculated by subtracting the threshold of wave V from threshold of RCDP RESULTS: Slope of the wave V latency-intensity curve low-intensity segment evolved with age, changing from (mean +/- SD) -90.8 +/- 41.6 to -27.8 +/- 4.1 micros/dB. Similar results were obtained from days 23 through 36. The pre-RCDP range diminished as puppies became older, decreasing from 40.0 +/- 7.5 to 20.5 +/- 6.4 dB. CONCLUSION AND CLINICAL RELEVANCE: Changes in slope of the latency-intensity curve with age suggest enlargement of the audible range of frequencies toward high frequencies up to the third week after birth. Decrease in the pre-RCDP range may indicate an increase of the audible range of frequencies toward low frequencies. Age-related reference values will assist clinicians in detecting hearing loss in puppies.     

Prevention of renal infection and urinary shedding in dogs by a Leptospira vaccination

Prevention of urinary shedding of Leptospira interrogans spp. by chronically infected dogs remains a key objective of the vaccination in dogs against leptospirosis which is a zoonotic disease. An inactivated bivalent vaccine composed of Leptospira interrogans serovars icterohaemorrhagiae [L. icterohaemorrhagiae] and canicola [L. canicola] bacterins was tested for its ability to protect puppies against a challenge exposure with L. icterohaemorrhagiae. The vaccine was administered twice at a 3-week interval to six puppies aged from 8 to 9 weeks. Six other puppies were used as unvaccinated controls. All puppies were challenged 2 weeks after the second vaccine injection by intraperitoneal (IP) administration of L. icterohaemorrhagiae (day 0). Clinical signs, haematological and biochemical changes and evidence of Leptospira in blood, urine and kidney were monitored for 4 weeks after the challenge exposure (days 0-28). Puppies were euthanised on day 28 for post-mortem and histological examinations of liver and kidney. Control group presented clinical pictures of severe or subclinical infection. One dog developed severe clinical signs (hypothermia, depression, anorexia, abdominal pain, dehydration, icterus, weight loss) and died on post-infection day (PID) 7 due to an acute renal failure. Gross and microscopic lesions were in accordance with this clinical pattern. In the five remaining control dogs, the challenge exposure induced mainly a systemic infection including leptospiraemia, leptospiruria and renal carriage. The vaccinated group remained healthy throughout the study period. In conclusion, immunisation with a Leptospira vaccine was shown to protect dogs against symptomatology and leptospiraemia, urine shedding and renal infection.