Hip dysplasia in Estrela mountain dogs: prevalence and genetic trends 1991-2005

Three hundred and thirteen Estrela mountain dogs were examined for hip dysplasia (HD) using the standard ventrodorsal hip extended view, and graded into five categories (A, B, C, D and E) using the Fédération Cynologique Internationale’s (FCI) scoring system. The Ortolani method was performed to evaluate hip joint laxity. Pedigree information was obtained from the Portuguese Kennel Club and the genetic trend was evaluated by calculating the mean breeding values (BVs) for the last 15 years, using the threshold model.HD was found in 66% of the dogs. There was low-moderate correlation between the results of the Ortolani test and FCI hip scores (r_s = 0.386; P < 0.001). Grades of hip dysplasia were equal in both males and females (P = 0.14) and in the animals’ right and left sides (P = 0.51). The mean BVs for HD were stable in dogs born between 1991 and 2003, and showed an improvement in 2004 and 2005. The data confirm the high prevalence and severity of HD in predisposed breeds that do not have breeding programmes in place. It also confirms an initial favourable change in BVs that is a likely consequence of the voluntary radiographic hip-screening programme.     

Seasonal variation in the hip score of dogs as assessed by the New Zealand Veterinary Association Hip Dysplasia scheme

Abstract

AIM: To determine whether there is a seasonal variation in the phenotypic hip score of dogs born in New Zealand as assessed by the New Zealand Veterinary Association (NZVA) canine hip dysplasia (CHD) scheme.

METHODS: Data from dogs born in New Zealand between 1988 and 2009 that have been scored for CHD were retrospectively evaluated for the effect of month of birth on radiographic phenotype. Data included both the total score and the subtotal score, comprising Norberg's angle, the subluxation score and changes to the cranial acetabular edge, for each dog. Datasets were created for all breeds combined and for the four most populous breeds using the scheme (German Shepherd dog, Labrador Retriever, Golden Retriever and Rottweiler) and stratified according to month of birth and season. Due to the skewed nature of the data, a Kruskal–Wallis Rank Sum test was used to test for statistical significance. Additionally, χ² analysis was performed using the median of each dataset (proportion above/below the median). The null hypothesis was that there would be no effect of month of birth, and hence seasonality, on hip phenotype for dogs born and scored in New Zealand by the NZVA.

RESULTS: For all breeds combined, month of birth had an effect on total and subtotal NZVA CHD scores (p<0.001) with a lower total hip score in the autumn months of March and April than other months. When individual large breed data were analysed, there was an effect of month of birth on total and subtotal scores for the Labrador Retriever and the Rottweiler (p≤0.05), but not the German Shepherd dog or Golden Retriever breeds.

CONCLUSIONS: Being born in the autumn was associated with a protective effect on hip phenotype in some breeds. These results suggest that weather and/or another seasonal factor may have a significant environmental effect on the phenotype of the coxofemoral joint.

CLINICAL RELEVANCE: The protective effect of being born in autumn suggests that a decreased level of exercise during subsequent development over winter may positively impact on final coxofemoral joint conformation. Whilst statistically significant, the magnitude of the sparing effect is not likely to be clinically relevant. However, this study, in concert with other studies, may suggest that the effects of exercise can be manipulated to improve hip phenotype.     

Inclination and Anteversion of Collum Femoris in Hip Dysplasia and Coxarthritis

Madsen, J.S. and E. Svalastoga: Inclination and anteversion of collum femoris in hip dysplasia and coxarthritis. Acta vet. scand. 1994, 35, 115-119.–Femoral neck angles were measured radiographically in 41 dogs examined for hip dysplasia. Steep femoral neck inclination was found to be a phenomenon of hip dysplasia and coxofemoral joint laxity. The altered biomechanics of a steep femoral neck inclination may be a factor in the pathogenesis of hip dysplasia and secondary osteoarthritis.     

Hip and sacroiliac disease: selected disorders and their management with physical therapy

Many problems in the hip area show movement dysfunctions of the hip joint in combination with the lumbar spine, sacroiliac joint, neurodynamic structures, and the muscular systems. Muscle strain injuries pertinent to the canine hip have been reported in the iliopsoas, pectineus, gracilis, sartorius, tensor fasciae latae, rectus femoris, and semitendinosus muscles. Physical diagnoses of this type of injury require palpation skills and the ability to specifically stretch the suspected musculotendinous tissue. Treatments shall incorporate modalities, stretches, specific exercises, and advisement on return to normal activity. Canine hip dysplasia (CHD) is a common finding in many large breed dogs. Physical treatments, preventative therapies, and rehabilitation could have a large role to play in the management of nonsurgical CHD patients with the goal to create the best possible musculoskeletal environment for pain-free hip function and to delay or prevent the onset of degenerative joint disease. Osteoarthritic hip joints can benefit from early detection and subsequent treatment. Physical therapists have long utilized manual testing techniques and clinical reasoning to diagnose early-onset joint osteoarthritis and therapeutic treatments consisting of correcting muscle dysfunctions, relieving pain, joint mobilizations, and advisement on lifestyle modifications could be equally beneficial to the canine patient. As well, sacroiliac joint dysfunctions may also afflict the dog. An understanding of the anatomy and biomechanics of the canine sacroiliac joint and application of clinical assessment and treatment techniques from the human field may be substantially beneficial for dogs suffering from lumbopelvic or hindlimb issues.     

Stratification,Blinding and Placebo Effect in a Randomized,Double Blind Placebo-controlled Clinical Trial of Gold Bead Implantation in Dogs with Hip Dysplasia

The purpose of this study was to investigate the need for and choice of stratification factors, and the effects of blinding and placebo in a clinical experiment. Eighty dogs with canine hip dysplasia (CHD) were included in a randomized, placebo-controlled and double blind clinical trial with stratified parallel group design, in which body weight and degree of CHD were used as stratification factors. Thirty-eight dogs were allocated to gold bead implantation and 42 to placebo. After six months, 33 of the 42 placebo-treated dogs received gold bead implantation in an open study lasting a further 18 months. The main outcome variable in the study was change in pain signs of CHD as assessed by the owner. No significant difference in the main outcome variable, regardless of the treatment given, could be detected in the two chosen stratification factors. The only factor to influence the main outcome variable significantly was age. The blinding procedure used in the study, in which 60% of the owners correctly guessed the treatment given, was found sufficient. Of those who guessed the treatment erroneously, 88% believed the treatment given was gold bead implantation. The treatment efficacy after six months in the blinded treatment group was found to be significantly larger compared to the efficacy obtained in the open study. A significant placebo effect was therefore detected. Conclusion and Clinical Relevance: The age of the dogs influenced the outcome of the CHD treatment, and is recommended as a stratification factor. A significant placebo effect has to be expected and an optimal blinding procedure is necessary in similar clinical studies.     

Osteochondral dysplasia of the coxofemoral joints in a Friesian foal: Clinical findings and methods of diagnosis

Diseases of the coxofemoral (hip) joint are infrequently diagnosed in horses. Most cases are presented as an unilateral condition and usually are of traumatic origin. This case report describes a Friesian foal with a clinically obvious thoracolumbar kyphosis, combined with a weight‐shifting stance and a shortened stride of both hindlimbs. General clinical and lameness examinations, computed tomographic examination of the pelvis, and macroscopic and histopathological examinations of the coxofemoral joints were performed. This revealed a final, phenotypical diagnosis of a primary osteochondral dysplasia of both coxofemoral joints with secondary osteoarthritis. Similar to the occurrence of this condition in other species and considering the small genetic basis of the Friesian horse breed, a genetic predisposing factor is suspected to play a key role in the developing mechanism of dysplastic coxofemoral joint disease in horses as illustrated with this case. Computed tomography scanning appears to be a useful imaging technique in the detection of coxofemoral joint disease in small horses and foals.     

Black Hair Follicular Dysplasia in Black and White Saluki Dogs: Differentiation from Color Mutant Alopecia in the Doberman Pinscher by Microscopic Examination of Hairs

Abstract— Four black and white female Saluki puppies developed variably severe hypotrichosis in black haired areas. Histologically, follicles in black haired areas were dilated with keratin and clumps of melanin pigment, and were irregularly shaped. Melanin pigment was also clumped in hair shafts, basal layer of epidermis, epithelial cells of hair bulbs and macrophages around follicles, especially at the base. White haired areas were normal grossly and histologically. Light microscopic examination of dehydrated and cleared primary black hair shafts from one Saluki with black hair follicular dysplasia and primary blue hair shafts from two blue Doberman pinschers with color mutant alopecia revealed that the blue Dobermans had many more visible macromelanosomes than the Saluki. On scanning electron microscopy, cuticular abnormalities were identified in some white and all black hairs from the Saluki. Several black hairs had shallow, oval defects in the superficial cortex. Blue hairs from one Doberman had similar, but more extensive changes. Résumé— Quatre chiots femelles Saluki noirs et blancs ont développé une hypotrichose plus ou moins étendue des zones de poils noirs. Sur le plan histologique, les follicules pileux des zones de poils noirs étalent dilatés, de forme irrégulière et obstrué par des bouchons de keratine et de mélanine. Des pigments mélaniques en motte sont aussi retrouvés dans la lumière des poits, les cellules basales de l'epiderme, les cellules épithéliales de bulbes pileux et les macrophages entourant les follicules pileux. Les zones de poils blancs étaient normales, tant macroscopiquement que micrioscopiquement. L'examen en microscopie optique de poils noirs primaires deshydratés et éclaircis provenant d'un de ces Saluki et de deux Doberman atteints d'alopécle des mutants de couleur a révélé un beaucoup plus grand nombre de macromélanosomes chez les Dobermans que chez le Saluki. En microscopie électronique à balayage des anomalies de la cuticule ont été observées sur quelques poils blancs et tous les poils noirs des Salukis. Plusieurs poils noirs présentaiert des déformations ovales peu profondes de la cuticule. Les poils bleus des Dobermans présentaient le même type de déformation, mais de façon plus étendue. Zusammenfassung— Vier schwarz-weiße weibliche Salukiwelpen entwickelten abwechselnd eine schwere Hypotrichose in den schwarzgefärbten Fellbezirken. Im histologischen Bild waren die Follikel in den schwarzgefärbten Fellbezirken durch Keratin und Melaninpigmentklumpen dilatiert sowie unregelmäßig geformt. Das Melaninpigment war in den Haarschäften, in der Basalzellschicht der Epidermis, den Epitheizellen der Haarbulbi und den Makrophagen um die Follikel, besonders an der Basis, ebenfalls zusammengekiumpt. Die weißen Fellbezirke waren makroskopisch und histologisch unverändert. Die lichtmikroskopische Untersuchung von dehydrierten und aufgehellten Schäften schwarzer Primärhaare eines Salukis mit follikulärer Dysplasie schwarzer Haare und der Untersuchung der Haarschäfte blauer Primärhaare zweier blauer Dobermannhunde mit Farbmutantenalopezie zeigte, daß die blauen Dobermänner viel mehr sichtbare Makromelanosomen als der Saluki aufwiesen. Bei der Untersuchung mit dem Elektronenmikroskop konnten Abnormitäten der Kutikula bei einigen weißen und bei alien schwarzen Haaren des Salukis festgestellt werden. Einige der schwarzen Haare zeigten flache, ovale Defekte in der oberflächlichen Rinde. Blaue Haare eines Dobermanns zeigten ähnliche, aber viel ausgedehntere Veränderungen. Resumen Cuatro cachorros hembra de Saluki negro y bianco se desarrollaron con variable gravedad hipotricosis en areas de pelo negro. Histológicamente los folículos de las zonas de pelo negro fueron dilatados con keratina y grupos de pigmento de melanina, y fueron irregularmente formados. El pigmento de melanina también fue encontrado irregularmente en el cuerpo del pelo, capa basal de la epidermis, células epiteliales de los bulbos pilosos y macrófagos alredador de los folículos, especialmente en la base. Las areas de pelo bianco eran normales en cuanto tanto macroscopicamente como histológicamente. El examen microscópico del cuerpo de pelos negros deshidratados y aclarados de un saluki con displasia folicular de pelo negro y cuerpo de pelo azul primario de dos Doberman pinschers con alopecia de color mutante, reveló que los Dobermans azules tenían muchos mas macromelanosomas visibles que el Saluki. Al microscopio electrónico se identificaron abnormalidades cuticubres en algunas pelos blancos y todos los negros en el Saluki. Varios pelos negros tenían pequenos defectos ovales en la corteza superficial. Los pelos azules de uno de los Doberman presentaban cambios similares pero más extensos.     

Effects of intertrochanteric varus osteotomy on Norberg angle and percent coverage of the femoral head in displastic dogs

This study was conducted to assess the effects of femoral varus osteotomy on joint congruency in dogs affected by early stage hip dysplasia. Preoperative planning to move the femoral head within the acetabulum was carried out. Varisation of the femoral inclination angle (fIA) was achieved by Intertrochanteric Osteotomy (ITO). Norberg angle (NA), percent coverage (PC) of the femoral head by the acetabulum and fIA was measured from preoperative, immediate postoperative and first and second recheck radiographs of seven dogs that underwent an ITO (joint n = 9). There was significant (p < 0.05) improvement of both NA and PC in all patients as indicated by a change in the mean ± standard deviation of 78.9° ± 7.5 and 36.9% ± 5.2 to 92.2° ± 6.7 and 50.6% ± 8.3, respectively. No significant difference (p < 0.05) was observed between the values of the planned femoral inclination angle (pfIA) of the femur and the effective femoral inclination angle (efIA) obtained after surgery (115.9° ± 2.5 and 111.3° ± 6.4, respectively). These findings could encourage the use of ITO in veterinary practice and indicate that intertrochanteric varus osteotomy should be re-considered for the treatment of early stage hip dysplasia in dogs with radiological signs of joint incongruency.     

Impact of sedation method on the diagnosis of hip and elbow dysplasia in Swedish dogs

Our objective was to investigate the effect of sedation method on the screening result for hip and elbow dysplasia. The study was based on a questionnaire survey of routines for hip and elbow screening at Swedish veterinary clinics and results of hip and elbow status, for eight breeds (Bernese Mountain Dog, Boxer, German Shepherd Dog, Golden Retriever, Labrador Retriever, Newfoundland, Rottweiler, and Saint Bernard) recorded by the Swedish Kennel Club. In total 5877 and 5406 dogs examined for hip and elbow dysplasia, respectively, from January 2002 through March 2003 were included. We used logistic regression to examine whether the type of chemical restraint used for sedation affected the screening result for hip and elbow dysplasia. In addition to sedation method, the effects of veterinary clinic, sex, breed, and age at screening were studied.

The type of chemical restraint used for sedation affected the screening result for hip but not for elbow dysplasia. Acepromazine gave less than half the odds of hip dysplasia compared with medetomidine and butorphanol (the most common method), medetomidine alone or xylazine. Females had about 25% higher odds for developing hip dysplasia whereas males had almost 40% higher odds for developing elbow dysplasia. Saint Bernard, Newfoundland and German Shepherd Dog had the highest odds of developing hip dysplasia, whereas Rottweiler and Labrador Retriever had the lowest odds. Boxer had the lowest risk for elbow dysplasia, followed by Labrador Retriever. Saint Bernard and Rottweiler had the highest odds of elbow dysplasia. Increasing age increased the odds of both hip and elbow dysplasia, by about 2.5% per month.

Following the results in this study, recording of the type of chemical restraint used for sedation during hip screening has now become mandatory in Sweden. This makes it possible to account for the effect of sedation method in a model for prediction of breeding values for hip dysplasia.     

Evaluation of serum chondroitin sulfate and hyaluronan: biomarkers for osteoarthritis in canine hip dysplasia

Hip dysplasia (HD) is one of the most important bone and joint diseases in dogs. Making the radiographic diagnosis is sometime possible when the disease has markedly progressed. Chondroitin sulfate (CS) and hyaluronan (HA) are the most important cartilage biomolecules that are elevated in the serum taken from dogs with osteoarthritis. The serum CS and HA can be detected by an ELISA technique, with using monoclonal antibodies against CS epitope 3B3 and WF6 and the HA chain as the primary antibodies. The aim of this study was to compare the levels of serum CS (both epitopes) and HA in non-HD and HD dogs. All 123 dogs were categorized into 2 groups. The non-HD group was composed of 98 healthy dogs, while the HD group was comprised of 25 HD dogs. Blood samples were collected for analyzing the serum CS and HA levels with using the ELISA technique. The results showed that the average serum level of the CS epitope WF6 in the HD group (2,594 ± 3,036.10 ng/ml) was significantly higher than that in the non-HD group (465 ± 208.97 ng/ml) (p < 0.01) while the epitope 3B3 in the HD group (105 ± 100.05 ng/ml) was significantly lower than that in the non-HD group (136 ± 142.03 ng/ml) (p < 0.05). The amount of serum HA in the HD group (134.74 ± 59.71 ng/ml) was lower than that in the non HD group (245.45 ± 97.84 ng/ml) (p < 0.05). The results indicate that the serum CS and HA levels might be used as biomarkers for osteoarthritis in HD dogs.     

Development of Clinical Signs and Occurrence of Feline Corona Virus Antigen in Naturally Infected Barrier Reared Cats and Their Offspring

The onset and pattern of the clinical signs of feline corona virus (FCoV) infection in cats were studied in a setting behind an isolation barrier. Two FCoV-seropositive cats were the source of the infection, and 3 barrier reared cats–initially FCoV-seronegative–were the recipients. The first clinical sign in the recipients appeared 11 days after contact with the source of infection. After 2 years 1 male and 1 female of the recipients started to breed. Their offspring developed clinical signs of disease at an age of 4-5 weeks. A pattern of recurring upper respiratory tract signs and conjunctivitis at intervals of about 4 months was observed in both the recipients and their offspring, while CNS dependent signs and wasting remained or got worse, once developed. Once demonstrated, FCoV antigen persisted in membrana nictitans throughout the investigation, and was found in all cats but 4 (90%). The offspring died during 2 periods, around the first week of life (9/37), and at 3-5 months of age (5/25). For comparison 3 offspring were euthanised at an age of 1 day and 16 offspring at an age of 3-6 months. FCoV antigen was demonstrated in all organs investigated (100%) from offspring dying during the first period, and in 97% from those dying during the second period. For the offspring euthanised during the same 2 periods the corresponding findings were 95% and 85%. Offspring euthanized between 9 and 17 months (4 kittens) had antigen in 67% of all investigated organs. The incidence of FCoV antigen in almost every organ in the investigated newborn kittens suggests an intrauterine infection. The demonstration of FCoV antigen in all euthanised cats, suggests a persistant infection. Virus was cultivated from membrana nictitans, that was FCoV antigen positive in the M3 test.     

Clinical and Laboratory Findings in Equine Piroplasmosis

The objective of this study was to evaluate equine piroplasmosis (EP) as a cause of morbidity in horses in Sardinia (Italy), describe the clinical signs and altered hematologic and biochemical parameters, and illustrate response to different treatments. Among 44 horses suspected of tick-borne disease, 38 were polymerase chain reaction (PCR) positive for Theileria equi (n = 27) or Babesia caballi (n = 6), whereas five were positive for both protozoans. Typical clinical features of piroplasmosis were seen in some of the horses, whereas others had nonspecific mild symptoms. Hematologic findings revealed involvement of the three blood cell lineages (anemia, leukopenia or leukocytosis, thrombocytopenia), and biochemical variations were related to increased bilirubin, alteration of serum phosphorus, and hypoalbuminemia. We suggest that the two protozoans are the most important causative agents of equine tick-borne disease in this geographic area, and we observe that different clinical features are associated with the disease; in addition to the typical aspects of piroplasmosis, characterized by fever, pale mucous membranes, and icterus, we can signal other nonspecific mild signs such as weight loss, weight loss associated with an insignificant leukopenia, or weight loss associated with depression, anorexia, and mild hyperbilirubin. The study is intended as a practical contribution for veterinary practitioners because it describes different clinical presentations and laboratory findings of EP, suggests diagnostic and therapeutic approaches to the disease, and shows diffusion of the disease in a Mediterranean region.