Male German Shepherd Dog Research Articles

Aggressive dogs are characterized by low omega-3 polyunsaturated fatty acid status

Canine aggressive behaviour is one of the most common problems being reported by dog owners. However, the biochemical basis of this phenomenon remains unclear. In humans, alterations in omega-3 plasma polyunsatured fatty acids and elevated omega6/omega-3 ratio have been linked to behavioural alterations, including aggression. Thus far, however, the relationship between plasma polyunsatured fatty acid status and aggression has not been investigated in the dog. In the present study we sought to investigate whether polyunsatured fatty acid status could be altered in plasma of pathologically aggressive Canis familiaris. Eighteen adult male German Shepherd dogs, aged 4.9 +/- 0.9 years, showing no clinical signs but aggression, were investigated. Eighteen healthy male dogs, aged 4.8 +/- 0.7 years, with a negative history of behavioural and neurological disorders served as controls. Baseline fasting plasma polyunsatured fatty acid composition was determined by gas chromatography. Compared to normal dogs, aggressive dogs showed lower docosahexaenoic acid (22:6 n-3) concentrations and a higher omega6/omega-3 ratio. In addition, they showed reduced cholesterol and bilirubin concentrations compared to their normally behaving counterparts. Altogether, our results suggest that low omega-3 fatty acids may adversely impact behaviour in dogs, resulting in greater propensity to aggression. However, given the cross-sectional design of our study, we cannot claim any causal relationship between the presence of alterations in fatty acid status and canine aggressiveness. Whether omega-3 fatty acids supplementation may be useful to reduce aggressive behaviour in the dog deserves further investigation.

Heterotopic implantation of a porcine bioprosthetic heart valve in a dog with aortic valve endocarditis

A 5-year-old male German Shepherd Dog was evaluated because of a 5-month history of progressive lethargy, weight loss, and heart failure. On physical examination, bounding femoral pulses and systolic and diastolic murmurs were detected. Echocardiography revealed severe aortic valve insufficiency (AVI) and a large vegetative lesion on the aortic valve consistent with aortic valve endocarditis. The AVI velocity profile half-time was 130 milliseconds; the calculated peak systolic pressure gradient across the aortic valve was 64 mm Hg. Left ventricular diameter during diastole was 63.6 mm (predicted range, 40.2 to 42 mm) and during systole was 42.9 mm (predicted range, 25.4 to 27 mm). Systolic, diastolic, and mean arterial blood pressures were 120, 43, and 65 mm Hg, respectively. To palliate severe AVI, the descending aorta was occluded (duration, 16.75 minutes) and heterotopic implantation of a porcine bioprosthetic heart valve in that vessel was performed. After surgery, systolic, diastolic, and mean arterial blood pressures were 115, 30, and 61 mm Hg, respectively, in the forelimb and 110, 62, and 77 mm Hg, respectively, in the hind limb. Within 6 months, the AVI velocity profile half-time had increased to 210 milliseconds, indicating diminished severity of AVI. After 24 months, the dog was able to engage in vigorous exercise; no pulmonary edema had developed since surgery. Heterotopic bioprosthetic heart valve implantation into the descending aorta during brief aortic occlusion appears feasible in dogs and may provide substantial palliation for dogs with severe AVI.

Reconstruction of the urethra by use of an inverse tubed bipedicle flap in a dog with hypospadias

A 1-year-old castrated male German Shepherd Dog was evaluated because of a history of hematuria and stranguria secondary to recurrent urinary tract infections. Physical examination revealed hypospadias with penile and preputial aplasia. The urethral orifice was just ventral to the ventral aspect of the anocutaneous junction. Ascending urinary tract infections, secondary to fecal contamination of the urethral orifice, were the presumed source of recurrent bouts of cystitis that developed despite periodic antimicrobial treatment. A 1-cm-diameter urethral extension was constructed from the urethral mucosal remnant located along the midline of the perineum (urethral trough). Two parallel 4-cm incisions (3 cm apart) were made lateral to that urethral trough. The borders were sutured to form an inverted, epithelium-lined tube (bipedicled flap) attached to the dorsal urethral orifice. The lateral skin margins were sutured over the reconstructed urethral extension, completing the procedure. Postoperative swelling necessitated temporary catheterization of the urinary bladder. After closure of a small fistula from the reconstructed urethral segment, the dog subsequently had only 2 episodes of cystitis during a 3-year period. To minimize skin irritation secondary to urine exposure, the dog's owner regularly trimmed the hair around the new urethral orifice. In dogs, correction of perineal (subanal) hypospadias via urethral reconstruction should be considered among treatment options. By use of an inverse tubed urethral extension, direct fecal contamination to the lower urinary tract may be effectively eliminated, dramatically reducing the incidence of ascending urinary tract infections in dogs with hypospadias.

Canine sertoli cell tumor: case report.

A 10-year-old male German shepherd dog was diagnosed with Sertoli cell tumor and paraneoplastic feminization syndrome

Gastric ulceration subsequent to partial invagination of the stomach in a dog with gastric dilatation-volvulus

CASE DESCRIPTION-An 8-year-old castrated male German Shepherd Dog was evaluated because of abdominal distension, retching, and vomiting. CLINICAL FINDINGS-Gastric dilatation-volvulus was suspected on the basis of the dog's signalment, history, clinical signs, and results of clinicopathologic analyses and abdominal radiography. Celiotomy was performed, and gastric dilatation-volvulus was confirmed along with splenomegaly. Gastric invagination was performed over an area of gastric necrosis. The dog was reevaluated 21 days later after an episode of collapse. Findings of physical examination and clinicopathologic analyses were suggestive of internal hemorrhage. Abdominal ultrasonography and subsequent celiotomy revealed severe gastric ulceration at the gastric invagination site, splenic torsion, and a focal splenic infarct. TREATMENT AND OUTCOME-Splenectomy and gastrectomy of the necrotic tissue were performed. The dog was discharged from the hospital, and the owner was instructed to administer gastroprotectants and feed the dog a bland diet. The dog was reported to be healthy 3.25 years after surgery. CLINICAL RELEVANCE-Findings suggest that complications associated with the gastric invagination procedure include severe gastric ulceration that may require subsequent surgery. Prolonged treatment with gastroprotectants following gastric invagination surgery may be necessary to avoid gastric ulceration in dogs.

Syncope secondary to transient atrioventricular block in a German shepherd dog with dilated cardiomyopathy and atrial fibrillation

This case report describes transient atrioventricular block as the etiology for syncopal events in a 6-year-old male German shepherd dog with atrial fibrillation and dilated cardiomyopathy. The arrhythmia diagnosis was obtained via Holter monitoring. Medical treatment with a sustained-release preparation of theophylline, as an additive to the standard congestive heart failure treatment (benazepril, furosemide and pimobendan) may have contributed to temporary remission of the syncopal events. However, the congestive heart failure progressed and the dog was euthanized. Veterinarians should be aware of the possibility of transient atrioventricular block causing syncope in dogs with DCM and AF and should be careful in empirically lowering the ventricular response rate if these dogs present with syncopal episodes.

Femoral compartment syndrome due to haemangiosarcoma in the semimembranosus muscle in a dog

A five-year-old, entire male German shepherd dog was presented to the Veterinary Teaching Hospital-Koret School of Veterinary Medicine because of an acute, painful swelling of the right thigh and severe lameness of two-weeks duration. On physical examination, a firm and painful mass was detected in the hamstring region. Radiography and ultrasonography revealed a soft tissue mass, with a 250 cc fluid accumulation craniomedial to it. Intracompartmental pressure measurement with a Wick catheter demonstrated significantly elevated pressure within the right caudal femoral compartment (25 to 28 mmHg compared with 5 to 7 mmHg in the unaffected leg). Surgical exploration of the area was undertaken, fasciotomy and mass excision were performed, and resolution of the clinical signs was achieved. The mass was identified by histopathology results as haemangiosarcoma. Two and a half months after surgery, which was followed by adjunct chemotherapy (doxorubicin), the dog was readmitted with a subcutaneous mass in the same area, although he was not lame at this time. Radiographs of the thoracic cavity demonstrated widely disseminated metastases in the lungs. At that point, the owner elected to have the dog euthanased.

Localised mid‐jejunal volvulus following intussusception and enteroplication in a dog

Ileocolic intussusception was successfully treated surgically by partial enterectomy and enteroplication in an 11-month-old, male neutered German shepherd dog. Segmental intestinal volvulus was identified in the same dog two months later and was managed successfully by a second partial enterectomy. The dog made an uneventful recovery and was free of clinical disease six months after the second surgery. Both conditions are reviewed in this case report and a possible relationship between these two episodes in this dog is discussed.

Use of a percutaneous atrial septal occluder device for complete acute occlusion of an intrahepatic portosystemic shunt in a dog

A 3-month-old sexually intact male German Shepherd Dog was evaluated because of signs of depression, ataxia, and collapse. Clinicopathologic abnormalities included low serum BUN and albumin concentrations and high serum liver enzyme activities and plasma ammonia and serum bile acids concentrations. Abdominal ultrasonography revealed an intrahepatic portosystemic shunt (PSS). The dog was anesthetized; via a transjugular approach, guidewires and catheters were directed with fluoroscopic guidance to locate the shunt and determine its anatomic features. Minimal changes in portal vein pressure during temporary shunt balloon occlusion enabled complete shunt attenuation, which was performed by use of a self-expanding septal occlusion device that is typically used for treatment of atrial septal defects in humans. Following initial misplacement of the device, the procedure was repeated successfully 2 months later and resulted in complete shunt occlusion. One year after this second procedure, the dog was clinically normal and serum bile acids concentration was within reference limits. In certain dogs with intrahepatic PSSs, treatment with minimally invasive interventional techniques involving fluoroscopy may reduce the morbidity and mortality rates associated with more invasive surgical procedures.

Treating pedal shortening in a dog by metatarsal distraction osteogenesis

A five-month-old, male German shepherd dog was presented with a left hindlimb deformity. Wearing a cast for a prolonged period to treat left metatarsal fractures at eight weeks of age had resulted in physeal closure of the calcaneus, metatarsals and phalanges. Hyperextension of the phalanges and ulceration of the plantar skin proximal to the main tarsal pad were seen. The left foot was 40 mm shorter than the right. At seven months of age, a modified circular external skeletal fixator (CESF) was used to perform distraction osteogenesis of the metatarsal bones for 28 days. The CESF apparatus was removed after eight weeks when there was radiographic consolidation of regenerate bone. At follow-up evaluations four and 12 months after surgery, the phalangeal hyperextension and plantar skin ulceration had resolved. No lameness was detected.

True grit: the tale of a subcutaneous mass in a dog

A 14-month-old, intact, male German Shepherd dog was referred for a 6 x 3-cm, firm mass in the left pelvic limb. Fine needle aspiration yielded chalky white material. May-Grünwald-Giemsa-stained smears showed a uniform background of amorphous, poorly stained, light-blue material and scattered foamy macrophages, a few naked nuclei, and cellular debris. The cytologic diagnosis of calcinosis circumscripta was confirmed by histologic evaluation of the surgically removed mass. In this report, we document the unique cytologic and histologic patterns of this uncommon tumor-like lesion.

Compound maxillary odontoma in a young German shepherd dog

A three-month-old, male German shepherd dog was admitted with a facial mass of two months' duration. Clinical examination showed a round mass, 3 cm in diameter, in the left infraorbital area. The upper last premolar deciduous tooth was not erupted. No other abnormalities were detected. Radiological examination revealed a posterior maxillary mass of mixed opacity. The mass was surgically excised. Histopathological examination demonstrated a connective tissue stroma containing foci of irregular enamel and dentine, resembling rudimentary teeth (denticles), surrounded by new bone formation. Morphology and structure of the denticles were also confirmed by scanning electron microscopy. A compound odontoma was diagnosed. One year after surgery, the dog was free of clinical signs.

Total hip replacement in a dog

An intact male German shepherd dog (4 y, body wt. 35.5 kg) was referred to the Animal Medical Center, Chonbuk National University with severe lameness, pain and gait abnormality on the right hind limb. Survey radiographs of the pelvis revealed dysplasia of the right coxofemoral joint with subluxation. The dog was surgically treated performing total hip replacement (THR) using Modular Biolox Canine Modular THR System. The dog began to bear weight and slowly returned to a normal exercise pattern 2 months after surgery. THR resulted in satisfactory clinical functions with 6 months follow up and no complications were observed. Canine modular THR could be a successful modality for the management of disabling conditions of the coxofemoral joint.

Sclerosing encapsulating peritonitis in a dog with leishmaniasis

Canine sclerosing encapsulating peritonitis is a rarely reported condition. A 10-year-old male German shepherd dog cross was presented with a history of ascites, vomiting, soft faeces, anorexia and depression. Gathering of the intestinal loops in the middle portion of the abdomen was detected by radiography and ultrasonography. Cytological examination of Giemsa-stained smears from the popliteal lymph nodes revealed Leishmania species. The results of culture of serosanguineous fluid obtained by abdominocentesis were negative for bacteria and fungi. Laparotomy revealed a sac of fibrous tissue encasing most of the intestinal loops and numerous adhesions extending between them. Histologically, an uneven, diffusely thickened, visceral peritoneal membrane was found. A diagnosis of idiopathic sclerosing encapsulating peritonitis was made. The dog was euthanased because the intestinal wall was torn at many sites during dissection of the membrane.

MULTICENTRIC LYMPHOMA WITH INTESTINAL INVOLVEMENT IN A DOG

A 5-year-old, male German shepherd dog was evaluated for a 5-week history of vomiting, diarrhea, lethargy, and weight loss. In abdominal radiographs, there was an unusual corrugated appearance within a loop of intestine. Sonographically, this loop also had a similar corrugated appearance with alternating hyperechoic and hypoechoic bands. Lymph nodes within the abdomen and thorax were enlarged, and a thoracic mass was also detected. Ultrasound-guided fine-needle aspirates of the mesenteric lymph nodes were highly suggestive of lymphoma. After postmortem examination, a diagnosis of multicentric lymphoma with involvement of the gastrointestinal tract was made.

Thoracoscopic anatomy of dogs positioned in lateral recumbency.

In four healthy, adult male German shepherd dogs, thoracoscopy was performed to provide a detailed description and illustration of the endoscopic anatomy of the normal intrathoracic structures of dogs. The dogs were anesthetized and placed in left or right lateral recumbency. The cannula and the endoscope were advanced into the thoracic cavity via entry of the free upper side in the dorsal third of the eighth intercostal space. Most intrathoracic structures of the left and right hemithorax were endoscopically visible. During the four thoracoscopic procedures, endoscopic photographs were taken and are illustrated in this paper. A sound knowledge of the anatomy of intrathoracic structures is a prerequisite for diagnostic and therapeutic thoracoscopy.

Breed and sex differences in growth curves for two breeds of dog guides.

A desirable dog guide weighs 18 to 32 kg as an adult. Male and female German shepherd dogs and male and female Labrador retrievers were weighed between birth and 18 mo of age, with at least one weight recorded after 290 d of age. Growth curves were constructed from 10,484 observations on 880 dogs using the Gompertz function in the form Wt = W(max)exp(-e[-(t-c)/b]), where Wt is weight at time t, Wmax is mature body weight, b is proportional to duration of growth, c is age at point of inflection, and t is age in days. Estimates for mature body weight were 2.4 +/- .3 kg higher for Labrador retrievers than for German shepherd dogs and 4.7 +/- .2 kg higher for males than for females. Male Labrador retrievers were closest to the upper limit for desirable weight, with an average estimated mature weight of 31.4 +/- .3 kg. Duration of growth, 4b + c, was not different between the breeds; however, the estimate for males was 8 +/- 5d longer than for females. Female Labrador retrievers had the shortest estimate for growth of 319 +/- 6 d. The estimate for age at the point of inflection was 3.6 +/- 1.2 d greater for males than for females, but not different between breeds. A better understanding of growth curves for dog guides may aid in estimating mature weight at a young age, thus allowing earlier breeding and training decisions to be made and increasing genetic change per year.

Epidemiology of Gastric Dilatation-Volvulus in the Military Working Dog Program

Examination of case records of 914 military working dogs which died during the period January 1, 1987-December 31, 1989, revealed 31 deaths (3.4%) due to gastric dilatation-volvulus (GDV) or its complications. The fata episode of GDV was the only reported occurrence of this condition in 81% of the dogs. Male German shepherd dogs, 6-10 years of age, that were fed a medicated high-energy ration once per day, predominated. Dogs in this study that had a prior history of acute gastric dilatation (AGD) or GDV, and that were decompressed by non-surgical means, eventually died of GDV. A comparison with dogs surviving an AGD or GDV episode from the same time period showed most to have had surgical decompression and gastropexy.

A degenerative myelopathy in young German shepherd dogs

ABSTRACTTwo young male German shepherd dogs, six and seven months old, were evaluated for progressive hindlimb ataxia and paresis. Both dogs were found to be thin and poorly muscled on physical examination, and on neurological examination, the lesions were localised to the spinal cord between T2 and L4. Microscopical examination of the spinal cords demonstrated widespread axonal degeneration similar to that seen in aged German shepherd dogs with chronic degenerative radiculomyelopathy (CDRM), although the distribution of these changes was not identical to CDRM.

Corneal endothelial cell degeneration in a German shepherd dog

ABSTRACTThe replacement of the normal endothelial cell morphology with formation of a fibrocellular posterior collagenous layer by the corneal endothelium was demonstrated in an eight‐year‐old male German shepherd dog with bilateral progressive corneal oedema. Descemet's membrane was multilaminar and thickened. The ultrastructural findings in this dog are similar but not identical to histological changes present in several human corneal diseases.