Comparison of tibial plateau angle between clinically normal Greyhounds and Labrador Retrievers with and without rupture of the cranial cruciate ligament

OBJECTIVE: To compare tibial plateau angle (TPA) between Greyhounds without damage to the cranial cruciate ligaments and Labrador Retrievers with and without damage to the cranial cruciate ligaments. DESIGN: Clinical study. ANIMALS: 87 client-owned dogs and 15 research colony Greyhounds. PROCEDURE: Standing position, horizontal-beam radiography was performed on Greyhounds and unaffected Labrador Retrievers to determine standing TPA. Lateral radiography of the stifle joint was performed on all dogs to determine traditional TPA. Age and body weight were recorded for unaffected and affected Labrador Retrievers. RESULTS: Greyhounds had mean standing TPA of 1.56 degrees and mean traditional TPA of 22.50 degrees. Unaffected Labrador Retrievers had mean standing TPA of 3.52 degrees and traditional TPA of 27.97 degrees. Affected Labrador Retrievers had mean traditional TPA of 25.55 degrees. No significant difference was found in mean standing TPA between Greyhounds and unaffected Labrador Retrievers. Standing TPAs in Greyhounds and unaffected Labrador Retrievers were not significantly different from a plane drawn parallel to the ground. Significant differences in traditional TPAs were detected among all 3 groups. CONCLUSIONS AND CLINICAL RELEVANCE: Greyhounds had mean traditional TPA of 22.50 degrees; similar angles should be considered normal for dogs. Although affected Labrador Retrievers had mean traditional TPA that was significantly greater than that of Greyhounds, the steepest TPA was found in unaffected Labrador Retrievers. Because Greyhounds and unaffected Labrador Retrievers had similar standing TPAs, we conclude that although TPA may be associated with damage to the cruciate ligaments, many dogs with a steep TPA do not develop cruciate ligament disease.     

Evaluation of a radiographic caudolateral curvilinear osteophyte on the femoral neck and its relationship to degenerative joint disease and distraction index in dogs

OBJECTIVE: To determine prevalence of a radiographic caudolateral curvilinear osteophyte (CCO) on the femoral neck in various breeds and age groups of dogs and to evaluate its contemporaneous relationship with degenerative joint disease (DJD) and distraction index (DI). DESIGN: Cross-sectional prevalence study. ANIMALS: 25,968 dogs, including 3,729 German Shepherd Dogs, 4,545 Golden Retrievers, 6,277 Labrador Retrievers, and 1,191 Rottweilers. PROCEDURE: Data from the University of Pennsylvania Hip Improvement Program database were analyzed, including ventrodorsal hip-extended, compression, and distraction radiographs. The CCO and radiographic signs of DJD were considered independent events and were interpreted as either present or absent. Statistical methods were used to evaluate the CCO as a possible risk factor for DJD and assess its association with DI, as measured by use of distraction radiography. RESULTS: When all breeds were pooled, DJD was detected in 8.6% of dogs, and the CCO was detected in 21.6% of dogs. Among dogs with a CCO, 25.1% had radiographic evidence of DJD. Among dogs without a CCO, only 4% had DJD. Dogs with a CCO were 7.9 times as likely to have DJD as were those without a CCO. Additionally, DI, weight, and age were significant risk factors for the CCO. CONCLUSION AND CLINICAL RELEVANCE: Results confirm the contemporaneous association between the CCO and DJD and that passive hip laxity, as measured by use of the DI, is associated with both the CCO and DJD.     

VERTEBRAL TUMORS IN THE DOG: A CLINICAL RADIOLOGIC, AND PATHOLOGIC STUDY OF 61 PRIMARY AND SECONDARY LESIONS

The clinical, radiographic, and histopathologic features of 26 primary and 35 secondary vertebral tumors of the dog with varying periods of clinical signs, possibly influenced by their being referred dogs, are presented. Pain without neurologic signs was the predominant initial sign with both primary and secondary tumors. However, by the time of hospital admission, most dogs had neurologic deficits. The time from pain onset to neurologic deficit ranged from two days to nine months. German Shepherd Dogs, Standard Poodles, and Labrador Retrievers were heavily represented; the average age was 7 years and there was a slight predominance of male dogs. Both primary and secondary tumors showed a destructive pattern, often with cortical destruction and adjacent disc space collapse. An associated paravertebral soft tissue mass was frequently present in the secondary tumors, 13 of 35 being secondary to intrapelvic tumors. Osteosarcomas were the most common primary tumor; the secondary tumor cell type varied. Most dogs were euthanized immediately upon histopathologic confirmation of the disease.     

Use of the caudolateral curvilinear osteophyte as an early marker for future development of osteoarthritis associated with hip dysplasia in dogs

OBJECTIVE: To determine the relationship between the caudolateral curvilinear osteophyte (CCO) and osteoarthritis associated with hip dysplasia in dogs. DESIGN: Longitudinal cohort study. ANIMALS: 48 Labrador Retrievers from 7 litters. PROCEDURE: In each of 24 sex- and size-matched pairs fed the same diet, a restricted-fed dog was fed 25% less than a control dog for life. The dogs' hips were evaluated in the standard ventrodorsal hip-extended radiographic projection at 16, 30, and 52 weeks of age and then yearly for life. Histologic examination of hip joint tissues was performed on 45 dogs. RESULTS: Median age at death was 11.2 years. Adjusting for feeding group, dogs with a CCO were 3.7 times as likely to develop radiographic signs of osteoarthritis than those without a CCO. Stratified by diet, 100% of the control dogs with a CCO developed radiographic signs of osteoarthritis and 55% of restricted-fed dogs with a CCO developed radiographic signs of osteoarthritis. The CCO was the first radiographic change seen in 22 of 29 (76%) dogs with osteoarthritis. Overall, 35 of 37 (95%) dogs with a CCO had histopathologic lesions of osteoarthritis. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate a relationship between a CCO on the femoral neck and subsequent development of radiographic signs of osteoarthritis in Labrador Retrievers evaluated over their life span. A CCO is an important early radiographic indication of osteoarthritis associated with canine hip dysplasia.     

Chronic hepatitis in Labrador Retrievers: clinical presentation and prognostic factors

BACKGROUND: An increased incidence of chronic hepatitis has been reported in Labrador Retrievers. HYPOTHESIS: A breed associated hepatopathy occurs in Labrador Retrievers. ANIMALS: Twenty-four client-owned Labrador Retrievers. METHODS: Medical records of dogs with histopathologic confirmation of chronic hepatitis were retrospectively reviewed. A clinical score based on clinical signs and the results of biochemical tests was generated for each dog. Hepatic biopsy specimens were scored for disease activity, fibrosis, and copper accumulation. RESULTS: The median age was 9.3 years (range, 3.9-14.0 years). Clinical signs included inappetence, vomiting, lethargy, and weight loss. All dogs had increases in serum activity of one or more hepatobiliary enzyme. Hyperbilirubinemia and hypoalbuminemia were present in 45% and 21% of dogs, respectively. The median clinical score was 2.9, with a range of 0-8. The median histopathology activity and the fibrosis scores were 3.5 (range, 1-6) and 3.0 (range, 0-4), respectively. Rhodanine-positive copper staining was present in 15 of 17 biopsy specimens, with a median score of 2.0 (range, 0-3). Median survival was 374 days (range, 1-2645 days). A prolonged prothrombin time (P = .013) and thrombocytopenia (P = .041) were associated with survival < 2 months. The presence of anorexia (P = .049), hypoglobulinemia (P = .045), or prolonged partial thromboplastin time (P = .033) were associated with shorter overall survival times. The clinical score correlated with survival time (P = .030) and histopathologic staging (P = .049). CONCLUSIONS AND CLINICAL IMPORTANCE: A progressive hepatopathy in Labrador Retrievers in this study was marked by chronic inflammation, fibrosis, and copper accumulation. A clinical scoring system that correlates with survival time may be useful as a noninvasive method to predict prognosis.     

Neurologic manifestations associated with hypothyroidism in four dogs

Hypothyroidism was believed responsible for peripheral and central neurologic abnormalities in 4 dogs. Clinical signs consisted of abnormalities of gait and postural reactions and dysfunction of multiple cranial nerves in all 4 dogs. Circling, hypermetria, and spontaneous verticle nystagmus were observed in some of the dogs. Hypothyroidism was diagnosed in all 4 dogs on the basis of low resting serum thyroxine concentration and inadequate response to thyroid stimulating hormone. After thyroid hormone supplementation, resolution of neurologic abnormalities was complete in 2 dogs and partial in the other 2 dogs.     

Salmon Poisoning Disease in Dogs: 29 Cases

Background: Salmon poisoning disease (SPD) is a trematode‐borne disease of dogs caused by Neorickettsia helminthoeca. Objectives: To determine risk factors and spatial epidemiology of SPD in dogs from northern California; to describe the clinicopathologic, microbiologic, and imaging findings of SPD in these dogs; and to evaluate treatments and outcomes for SPD. Animals: Twenty‐nine dogs with SPD based on the finding of trematode ova in the feces, or organisms consistent with N. helminthoeca in specimens submitted for microscopic examination. Methods: Information regarding signalment, fish exposure, clinical signs, diagnostic evaluation, treatments, and outcomes was obtained for each dog. Archived lymph node aspirates and histopathology specimens were subjected to polymerase chain reaction (PCR) testing for Neorickettsia spp. Results: Labrador Retrievers and intact male dogs were overrepresented. Exposure locations were often distant from the dogs' residence. Some dogs had neurologic signs, including twitching and seizures. Dogs lacking peripheral lymphadenomegaly had abdominal lymphadenomegaly on ultrasound examination. A combination of centrifugation fecal flotation and sedimentation had greatest sensitivity for finding fluke ova. N. helminthoeca DNA was amplified by PCR from 4/10 dogs. Penicillins, cephalosporins, and chloramphenicol did not appear to be effective treatments. Mortality rate was 4/29 (14%). Conclusions and Clinical Importance: SPD should be suspected in dogs with inappetence, gastrointestinal, or neurologic signs, with or without fever or peripheral lymphadenomegaly in the appropriate geographical setting. Diagnosis is facilitated by a combination of fecal sedimentation and centrifugal flotation, abdominal ultrasonography, and PCR‐based assays on lymphoid tissue. The treatment of choice is tetracycline antimicrobials.     

Effect of surgical technique on limb function after surgery for rupture of the cranial cruciate ligament in dogs

OBJECTIVE: To determine the outcome and effect of surgical technique on limb function after surgery for rupture of the cranial cruciate ligament (RCCL) and injury to the medial meniscus in Labrador Retrievers. STUDY DESIGN: Prospective clinical study. ANIMALS: 131 Labrador Retrievers with unilateral RCCL and injury to the medial meniscus and 17 clinically normal Labrador Retrievers. PROCEDURE: Affected dogs had partial or complete medial meniscectomy and lateral suture stabilization (LSS), intracapsular stabilization (ICS), or tibial plateau leveling osteotomy (TPLO). Limb function was measured before surgery and 2 and 6 months after surgery. Treated dogs were evaluated to determine the probability that they could be differentiated from clinically normal dogs and tested to determine the likelihood that they achieved improvement. RESULTS: No difference was found between LSS or TPLO groups, but dogs treated with ICS had significantly lower ground reaction forces at 2 and 6 months. Compared with clinically normal dogs only, 14.9% of LSS-, 15% of ICS-, and 10.9% of TPLO-treated dogs had normal limb function. Improvement was seen in only 15% of dogs treated via ICS, 34% treated via TPLO, and 40% treated via LSS. CONCLUSIONS AND CLINICAL RELEVANCE: Surgical technique can influence limb function after surgery. Labrador Retrievers treated via LSS, ICS, or TPLO for repair for of RCCL and medial meniscal injury managed with partial or complete meniscectomy infrequently achieve normal function. Results of LSS and TPLO are similar and superior to ICS.     

Inhibitory and excitatory neurotransmitters in the cerebrospinal fluid of epileptic dogs

OBJECTIVE: To determine concentrations of excitatory and inhibitory amino acids in CSF of a large number of dogs with idiopathic epilepsy or genetic epilepsy and to evaluate changes in CSF amino acid concentration with regard to drug treatment and sex. ANIMALS: 35 Labrador Retrievers with genetic epilepsy (20 male and 15 female), 94 non-Labrador Retrievers with idiopathic epilepsy (71 male and 23 female), and 20 control dogs (10 male and 10 female). PROCEDURE: Collection of CSF was performed > 72 hours after the occurrence of seizures. Cerebrospinal fluid concentrations of gamma-aminobutyric acid (GABA), glutamate (GLU), aspartate (ASP), serine, and glycine were determined by use of high performance liquid chromatography with electrochemical detection. RESULTS: CSF concentrations of GABA and GLU were significantly lower in Labrador Retrievers with genetic epilepsy (LR-group dogs) than in control-group dogs or in non-Labrador Retrievers with idiopathic epilepsy (non-LR-group dogs). The GLU-to-GABA ratio was significantly higher in LR-group dogs than in non-LR-group dogs. CSF concentrations of GLU and ASP were significantly lower when all dogs with epilepsy (non-LR- and LR-group dogs combined) were compared with control-group dogs. CONCLUSIONS AND CLINICAL RELEVANCE: A decrease in CSF concentrations of GABA appears to play a role in the pathogenesis of genetically determined epilepsy in Labrador Retrievers. However, this decrease in CSF concentrations of GABA may also be a consequence of seizure activity. The GLU-to-GABA ratio may prove to be a useful indicator of genetic epilepsy in Labrador Retrievers.     

Effect of 131I-induced hypothyroidism on indices of reproductive function in adult male dogs

Hypothyroidism has been cited as a cause of infertility, abnormal semen quality, and poor libido in people and animals. The purpose of this study was to evaluate the effect of hypothyroidism on variables indicative of reproductive function in adult male dogs. Nine normal dogs were randomly assigned to 2 groups. Hypothyroidism was induced with 131I in 6 dogs. Three dogs remained untreated, normal, and euthyroid. Thyroid hormone concentrations, body weight, clinical signs, and reproductive function were determined for each dog every 3 months for 2 years. Reproductive function was assessed by determining daily sperm output, total scrotal width, spermatozoal motility and morphology, libido, and serum testosterone and luteinizing hormone concentration responses to exogenous gonadotropin-releasing hormone. The 131I-treated dogs developed clinical and laboratory signs of hypothyroidism. In the hypothyroid dogs, serum concentrations of thyroid hormones were consistently below the reference range and were significantly lower than that in the euthyroid dogs. There was no difference in reproductive function between the hypothyroid and euthyroid dogs. The results of this study show that 131I-induced hypothyroidism does not affect indices of reproductive function in adult male dogs.     

Leucoencephalomalacia and Cerebral White Matter Vacuolar Degeneration in Two Related Labrador Retriever Puppies

Two Labrador Retriever dogs from a common dam had similar neurological deficits consisting of cortical blindness, dullness, and loss of previously learned habits. Both were examined at 5 months of age, and histopathological examination revealed leucoencephalomalacia and vacuolar degeneration of the cerebral white matter. Histopathologic findings in these 2 dogs differed from those reported previously in Labrador Retrievers with spongy degeneration of central nervous system white matter. A nonlittermate full sibling to 1 of these dogs was examined at 1.5 years of age for similar clinical signs that did not progress for the next 25 months.     

Post‐radiotherapy hypothyroidism in dogs treated for thyroid carcinomas

Hypothyroidism is a common adverse event after head and neck radiotherapy in human medicine, but uncommonly reported in canine patients. Records of 21 dogs with histologically or cytologically confirmed thyroid carcinoma receiving definitive or hypofractionated radiotherapy were reviewed. Nine cases received 48 Gy in 12 fractions, 10 received 36 Gy in 4 fractions and 2 received 32 Gy in 4 fractions. Seventeen cases had radiotherapy in a post‐operative setting. Ten cases developed hypothyroidism (47.6%) after radiotherapy. The development of hypothyroidism was not associated with the radiotherapy protocol used. Median time to diagnosis of hypothyroidism was 6 months (range, 1–13 months). Hypothyroidism is a common side effect following radiotherapy for thyroid carcinomas. Monitoring of thyroid function following radiotherapy is recommended. No specific risk factors have been identified.     

Distribution of power across the hind limb joints in Labrador Retrievers and Greyhounds

OBJECTIVE: To quantify angular excursions; net joint moments; and powers across the stifle, tarsal, and metatarsophalangeal (MTP) joints in Labrador Retrievers and Greyhounds and investigate differences in joint mechanics between these 2 breeds of dogs. ANIMALS: 12 clinically normal dogs (6 Greyhounds and 6 Labrador Retrievers) with no history of hind limb lameness. PROCEDURE: Small retroreflective markers were applied to the skin over the pelvic limb joints, and a 4-camera kinematic system captured data at 200 Hz in tandem with force platform data while the dogs trotted on a runway. Breed-specific morphometric data were combined with kinematic and force data in an inverse-dynamics solution for stance-phase net joint moments and powers at the stifle, tarsal, and MTP joints. RESULTS: There were gross differences in kinematic patterns between Greyhounds and Labradors. At the stifle and tarsal joints, moment and power patterns were similar in shape, but amplitudes were larger for the Greyhounds. The MTP joint was a net absorber of energy, and this was greater in the Greyhounds. Greyhounds had a positive phase across the stifle, tarsal, and MTP joints at the end of stance for an active push-off, whereas for the Labrador Retrievers, the only positive phase was across the tarsus, and this was small, compared with values for the Greyhounds. CONCLUSIONS AND CLINICAL RELEVANCE: Gross differences in pelvic limb mechanics are evident between Greyhounds and Labrador Retrievers. Joint kinetics in specific dogs should be compared against breed-specific patterns.     

Comparison of measurements obtained by use of an electrogoniometer and a universal plastic goniometer for the assessment of joint motion in dogs

OBJECTIVE: To compare measurements obtained by use of a universal plastic goniometer (UG) and an electrogoniometer (EG) and from radiographs and to compare joint motion in German Shepherd Dogs and Labrador Retrievers. ANIMALS: 12 healthy adult German Shepherd Dogs and data previously collected from 16 healthy adult Labrador Retrievers. PROCEDURES: German Shepherd Dogs were sedated. One investigator then measured motion of the carpal, cubital (elbow), shoulder, tarsal, stifle, and hip joints of the sedated dogs. Measurements were made in triplicate with a UG and an EG. Radiographs were taken of all joints in maximal flexion and extension. Values were compared between the UG and EG and with values previously determined for joints of 16 Labrador Retrievers. RESULTS: An EG had higher variability than a UG for all dogs. The EG variability appeared to result from the technique for the EG. German Shepherd Dogs had lower values in flexion and extension than did Labrador Retrievers for all joints, except the carpal joints. German Shepherd Dogs had less motion in the tarsal joints, compared with motion for the Labrador Retrievers, but had similar motion in all other joints. CONCLUSIONS AND CLINICAL RELEVANCE: A UG is reliable for obtaining measurements in German Shepherd Dogs. There was higher variability for the EG than for the UG, and an EG cannot be recommended for use.     

Blood–brain‐barrier disruption in chronic canine hypothyroidism

Background: Central nervous system (CNS) manifestations of hypothyroidism have been associated with cerebrovascular complications. Reports of cerebrospinal fluid (CSF) abnormalities are rare in hypothyroid dogs. Objective: The aim of this study was to determine if chronic hypothyroidism causes blood–brain‐barrier (BBB) abnormalities that are detectable using indirect CSF biomarkers. Methods: The study included 18 normal, euthyroid, female mixed‐breed dogs. Hypothyroidism was induced by ¹³¹iodine administration in 9 dogs; 9 served as untreated controls. Evaluations included physical and neurologic examination, complete CSF analysis, serum and CSF protein electrophoresis, measurement of plasma vascular endothelial growth factor (VEGF) and serum S‐100B concentrations, and calculation of CSF albumin quota (AQ) and were conducted at baseline and 6, 12, and 18 months after induction of hypothyroidism. Data were analyzed using repeated measures ANOVA. Results: At baseline, differences between groups were not detected for any variable. Throughout the study, controls dogs remained free of neurologic disease and had test variables that remained within reference intervals. Two hypothyroid dogs developed CNS signs during the study, and evidence of cerebrovascular disease was found at necropsy. At 12 and 18 months, the CSF total protein, VEGF, S‐100B, and fractional albumin concentrations, and AQ were significantly higher (P<.04) in hypothyroid dogs than controls. Among test variables assayed in serum or plasma, the only significant difference was a higher S‐100B concentration in hypothyroid dogs (P=.003) at 18 months. Conclusions: BBB integrity is disrupted in chronic hypothyroidism. Significant increases in CSF concentrations of VEGF and S100‐B in hypothyroid dogs indicate dysfunction in both endothelial and glial elements of the BBB.     

A cross-sectional study of epilepsy in Danish Labrador Retrievers: prevalence and selected risk factors

The purpose of this study was to investigate the prevalence and selected risk factors of epilepsy, the proportion of dogs with epilepsy in remission, and the types of seizures in Danish Labrador Retrievers. A prospective cross-sectional study of epilepsy was conducted in 1999-2000. The study was carried out in 2 phases in a reference population consisting of 29,602 individuals. In phase 1, 550 dogs were selected by random sampling stratified by year of birth. A telephone interview was used to identify dogs with possible epilepsy. In phase 2, dogs judged during phase 1 as possibly suffering from epilepsy were further subjected to physical and neurologic examination, CBC, blood chemistry, and a questionnaire on seizure phenomenology. Seventeen dogs were diagnosed with epilepsy, yielding a prevalence of 3.1% (95% CI 1.6-4.6%) in the Danish population of Labrador Retrievers. A diagnosis of epilepsy was 6 times more probable in dogs >4 years (born before 1995) than in younger dogs (born between 1995 and 1999) (P = .004, relative risk = 6.5). No significant difference in risk between genders was observed, nor could any effect of neutering be proven statistically. The frequencies of primary generalized seizures and partial seizures (with or without secondary generalization) were 24 and 70%, respectively. The type of seizures could not be classified in 6%. In conclusion, the 3.1% prevalence of epilepsy in Danish Labrador Retrievers is higher than the 1% prevalence of epilepsy described in the general canine population, establishing that this breed is at increased risk.     

Copper-associated chronic hepatitis in Labrador Retrievers

This study summarizes the clinical and pathologic findings in 15 Labrador Retrievers with copper-associated chronic hepatitis (CACH). Our hypothesis was that this form of hepatitis is caused by a defect in hepatic copper metabolism, which most likely originates from a genetic defect. Affected Labradors consisted of 11 female and 4 male Labrador Retrievers. Eight family members of 2 of these patients were examined prospectively, as were 6 unrelated healthy Labrador Retrievers. All dogs were registered at the breed club. The average age at clinical presentation was 7 years (range, 2.5-10.5 years). All dogs were presented for anorexia, which was associated with vomiting in 8 patients. The diagnosis of CACH was based on histologic examination of liver biopsy specimens in all dogs, including semiquantitation of copper. A disproportionate increase in alanine aminotransferase (ALT) activity relative to alkaline phosphatase (ALP) activity, as well as the centrolobular localization of copper and the association of copper accumulation with hepatic lesions, suggested a primary copper storage disease rather than primary cholestatic liver disease causing copper accumulation. Mean hepatic copper concentration measured in related Labradors was 1,317 microg/g dry weight liver (range, 402-2,576 microg/g). Mean hepatic copper concentration of unrelated normal Labradors was 233 microg/g dry weight liver (range, 120-304 microg/g). Our findings support the hypothesis that a hereditary form of hepatitis occurs in Labrador retrievers and is caused by a defect in hepatic copper metabolism.     

Polioencephalomalacia in the dog

Disturbance of cerebral blood flow from causes such as meningitis, thromboembolic disease and atherosclerosis was considered an important factor in the pathogenesis of polioencephalomalacia in 25 dogs. In dogs with polioencephalomalacia of undetermined cause, the distribution of lesions in neocortex and paleocortex suggested a change of neuronal metabolism secondary to cerebral anoxia/ischemia. Five dogs with canine distemper infection had bilateral necrosis of the hippocampus and pyriform cortex. Convulsions, central visual impairment and hemiparesis were the most prominent neurologic signs.     

Quantification of measurement of femoral head coverage and Norberg angle within and among four breeds of dogs

OBJECTIVE: To report values for percentage coverage of the femoral head (PC) and Norberg angle (NA) in 4 common breeds of dogs and to determine values for each that distinguish between normal and dysplastic hip status on the basis of Orthopedic Foundation for Animals (OFA) hip evaluation. ANIMALS: 1,841 dogs 24 to 48 months of age that were Labrador Retrievers (455), Golden Retrievers (423), Rottweilers (545), or German Shepherd Dogs (418). PROCEDURE: Retrospective analysis of NA and PC measured from standard OFA ventrodorsal pelvic radiographs from 4 breeds of dog. RESULTS: Norberg angle ranged from 67.4 to 124.4 degrees for Labrador Retrievers, 59.7 to 128.6 degrees for Rottweilers, 70.2 to 119.4 degrees for Golden Retrievers, and 55.3 to 121.3 degrees for German Shepherd Dogs. The PC ranged from 6.5 to 79.9% for Labrador Retrievers, 5.7 to 79.5% for Rottweilers, 8.3 to 79.3% for Golden Retrievers, and 5.4 to 83.7% for German Shepherd Dogs. On the basis of logistic regression modeling for determining normal versus abnormal hip status for all 4 breeds, cutoff points for NA were <105 degrees and PC were <50%. CONCLUSIONS AND CLINICAL RELEVANCE: Results of our study indicate that cutoff points of NA of 105 degrees and PC of 50% do not differentiate normal versus dysplastic hip status. Each of the 4 breeds had different values for NA and PC that distinguished normal from dysplastic hip status.