Ventral Approach to the Pelvic Canal in the Female Dog

A ventral approach to the pelvic canal by bilateral pubic and ischial osteotomy was performed in five female dogs. The entire urogenital tract could be exposed and easily manipulated through this approach. All animals were ambulatory within 24 hours. Clinical union had formed in three of the four osteotomies by the time of euthanasia (months 2-4) in all animals. Incomplete union in some osteotomies indicated that exercise should be restricted for at least 4 months after the procedure. The procedure was determined to be clinically useful when wide exposure of the entire female urogenital tract is desired.     

Effect of Application of Polyvinilidine Plates on the Dorsal Spinous Processes of Dogs

Anecdotal comments in the literature suggest that spinous fracture many weeks after application of polyvinilidine plates to the dorsal spinous processes of dogs may be due to associated adverse vascular changes. This study was undertaken to evaluate that hypothesis. Large size Lubra plates were cut to the appropriate length and applied to the dorsal spines of vertebrae L3 and L4. Vertebrae L2 and L5 served as operated controls. Vertebrae L1 and L6 served as unoperated normals. Two dogs were euthanized 1 week postoperatively, and three dogs each at 4, 8, and 12 weeks. The effect of the plate on the dorsal spinous processes was evaluated using microangiography and correlated histology. There was no apparent change in vascular architecture associated with plate application, nor with surgery alone, at any time interval. There did appear to be a time dependent loss of bone associated with plate application, indicating a change in the relative balance of osteoblastic and osteoclastic activity, and altered bone turnover.     

Caudal Approach to the Shoulder Joint in the Dog

A caudal approach to the scapulohumeral joint for treatment of osteochondritis dissecans of the humeral head was performed in seven dogs. By 14 days after surgery, three of the seven dogs were walking normally. At 6 weeks after surgery, all dogs were considered sound. Visualization was adequate for curettage of the osteochondritis dissecans lesions. Access to the medial joint compartment also was afforded.     

Magnetic Resonance Imaging (MRI) Spinal Cord and Canal Measurements in Normal Dogs

The goal of this study was to establish Magnetic resonance imaging (MRI) reference ranges for spinal measurements in normal dogs. Forty dogs (1–10 kg, 11–20 kg, 21–30 kg, > 30 kg; 10 dogs per category) underwent spinal MRI. Measurements were performed on sagittal T2‐W images at the level of the 4th thoracic vertebra (T4), the 9th thoracic vertebra (T9) and the 3rd lumbar vertebra (L3). Spinal canal diameter (mm) ranged from 6.07 ± 0.63 (1–10 kg) to 8.27 ± 1.15 (> 30 kg) at the level of T4; 6.55 ± 0.61 (1–10 kg) to 9.04 ± 1.26 (> 30 kg) at the level of T9; and 6.80 (6.47–7.00; 1–10 kg) to 9.00 (7.90–9.73; > 30 kg) at the level of L3. There were significant differences (P < 0.05) in spinal canal diameter between groups. Mean spinal cord diameter (mm) ranged from 4.46 ± 0.51 (11–20 kg) to 4.70 ± 0.35 (1–10 kg) at the level of T4; 4.41 ± 0.50 (> 30 kg) to 4.85 ± 0.57 (1–10 kg) at the level of T9; and 4.52 ± 0.51 (> 30 kg) to 5.14 ± 0.68 (1–10 kg) at the level of L3. There were no significant differences in spinal cord diameter between groups. Spinal cord‐to‐spinal canal ratio varied significantly, ranging from 0.51 ± 0.08 (> 30 kg at L3) to 0.78 (0.69–0.80; 1–10 kg at T4) (P < 0.05). These findings are important when using MRI to evaluate patients with suspected diffuse spinal cord disease.     

Effect of Desmopresssin in Normal Dogs and Dogs with von Willebrand's Disease

Desmopressin acetate (DDAVP(R)), a synthetic analogue of vasopressin was slowly administered intravenously to 12 healthy dogs of various breeds and 10 Doberman Pinschers with mild-to-moderate type I von Willebrand's disease at a dose of 0.3, 1.0 and 3.0 micro g/kg body weight. Plasma von Willebrand factor:antigen was measured by an electroimmunoassay prior to and 30, 60, 90, 120 and 180 minutes after desmopressin infusion. Desmopressin induced only very modest and statistically insignificant increases in von Willebrand factor in both groups. We conclude that the response to desmopressin as measured by circulating von Willebrand factor is much less pronounced in healthy dogs and in Doberman Pinschers with von Willebrand's disease than in humans.     

Effect of Thyrotropin Storage on Thyroid-Stimulating Hormone Response Testing in Normal Dogs

The stability of reconstituted, refrigerated thyrotropin was evaluated. Thyrotropin (TSH) was reconstituted at the start of the study and stored at 4 degrees C. A TSH stimulation test was performed in eight healthy, euthyroid dogs at weekly intervals for 1 month. In seven of eight dogs, there was no significant difference (P less than 0.05) between the post-TSH T3 concentrations and the post-TSH T4 concentrations for the duration of the study. For one dog, the post-TSH T4 concentration was below the normal post-TSH T4 range following the administration of reconstituted TSH that had been stored 4 weeks. The T3 response to the TSH, however, was normal. This dog responded normally to freshly reconstituted TSH. The results of this study suggest that reconstituted bovine TSH can be stored at 4 degrees C for at least 3 weeks without loss of biologic activity in the dog.     

Urinary Bladder Incisions in Dogs Comparison of Ventral and Dorsal

The occurrence of postoperative adhesions following ventral (20 dogs) or dorsal (12 dogs) urinary bladder incisions was evaluated. The bladder incisions were sutured with 3–0 polydioxanone suture material in a two-layer closure. Laparotomy (no urinary bladder incision) was performed in four dogs, which served as controls. The surgical sites were examined 1 (30 dogs) and 2 weeks (6 dogs) after surgery. Omental adherence to the urinary bladder was a frequent finding, but none of the urinary bladders was adhered to the ventral abdominal wall incision.     

Evaluation of Experimental Transection and Partial Excision of the Caudal Cruciate Ligament in Dogs

The caudal cruciate ligament (CaCL) of one stifle joint in seven dogs was transected and a 2 to 4 mm section was removed. Six months after surgery, none of the dogs were lame. Thigh muscle circumference, stifle range of motion, and internal tibial rotation in the operated limb were not significantly different from the preoperative measurements or the contralateral, unoperated limb. A caudal drawer motion was consistently present in the stifle joints with a transected CaCL. A radiographic evaluation of the operated stifle joints did not reveal osteoarthritic changes; four of seven stifle joints had an irregular fat pad 6 months after surgery. Results of a joint fluid analysis revealed a slight increase in synovial cells within treated stifle joints; inflammatory cells were not observed. The only gross morphologic change in stifle joints with a severed ligament was enlarged knobby remnants of the CaCL. Articular cartilage defects or osteophytes were not observed. Results of a histologic examination of the CaCL remnants revealed synovial cellular capping and intraligamentous fibroplasia. Based on a limited number of dogs, it was concluded that isolated transection of the CaCL produced minimal clinical and pathologic changes in the stifle joint during a 6 month period.     

The Effect of Triple Pelvic Osteotomy on Hip Force in Dysplastic Dogs: A Theoretical Analysis

The effect of a triple pelvic osteotomy (TPO) procedure on the forces acting about the hip joint was examined in five dysplastic canine hips using a previously described theoretical analysis. Hip reaction force (F_h) and its angle of application (θ_h) were calculated from radiographic measurements made before and after TPO procedures which sequentially increased acetabular ventroversion from 0° to 20°, 30°, and 40°. The results of the in vitro study showed that F_h decreased with increasing acetabular ventroversion reaching an asymptotic value between 30° and 40°. The decrease in F_h corresponded to an increase in θ_h toward the vertical, with statistical significance found in both F_h and θ_h between 0° and 20°. The changes observed in F_h and θ_h after TPO were attributed to the medialization of the femoral head resulting from the reduction of the subluxated head. The results of this study suggest that the noted reduction in the magnitude of the forces acting on the hip joint may act in concert with increased coverage of the femoral head to effect the beneficial clinical results observed with the TPO procedure.     

Plasma Taurine Concentrations in Normal Dogs and in Dogs With Heart Disease

Plasma taurine concentrations were determined in 76 dogs with dilated cardiomyopathy (DCM), 28 dogs with acquired valvular disease (AVD), and 47 normal (control) dogs. The data were collected at 2 referral centers. The Animal Medical Center, New York, NY (AMC), and the University of California, Davis (UCD), and the studies were conducted independently. Different anticoagulants (sodium citrate at AMC and lithium heparin at UCD) were used to collect the plasma samples. Paired analysis of samples showed a significant difference in plasma taurine concentrations, depending on the anticoagulant used. Consequently, results from each clinic were analyzed separately. Plasma taurine concentrations were significantly higher in dogs with AVD (median, 133 nmol/mL; range, 25 to 229 nmol/mL) than in control dogs (median, 63 nmol/mL; range 44 to 224 nmol/mL) and dogs with DCM (median, 72 nmol/mL; range, 1 to 247 nmol/mL) at AMC (P= .001). The number of dogs with AVD at UCD was too small to draw meaningful conclusions. At UCD, the median plasma taurine concentration was 98 nmol/mL (range, 28–169 nmol/mL) in dogs with AVD, 75 nmol/mL (range, 0.1–184 nmol/mL) in dogs with DCM, and 88 nmol/mL (range 52–180 nmol/mL) in control dogs. There were no significant differences in plasma taurine concentrations between dogs with DCM and the control dogs at either hospital. Congestive heart failure and administration of cardiac medication had no significant effect on plasma taurine concentrations. Plasma taurine concentration was low (<25 nmol/mL) in 17% (13/76) of the dogs with DCM. Seven of the 13 dogs with low plasma taurine concentrations were Cocker Spaniels or Golden Retrievers. It was concluded that most dogs with DCM do not have low plasma taurine concentrations. However, certain breeds or individual dogs may have low plasma taurine concentrations in association with DCM. Whether this association is causal or not is unknown. The significance of the high plasma taurine concentrations in dogs with AVD is also unknown.     

Effect of Hyposensitization with Irrelevant Antigens on Subsequent Allergy Test Results in Normal Dogs

Abstract— Five normal greyhounds were evaluated for hypersensitivity to various grasses, weeds, trees and fungi with both an intradermal allergy test and a commercial enzyme-linked immunosorbent assay (ELISA). All dogs were hyposensitized for 6 months with the same mixture of 14 allergens, according to the treatment schedule recommended by the commercial laboratory that provided the ELISA allergy test. Following hyposensitization with irrelevant antigens at a concentration of 1:200 w/v, dogs were reevaluated for hypersensitivity with the intradermal allergy test. No significant increase in intradermal reactions was found after 6 months of hyposensitization, and all dogs remained asymptomatic during the study period. Hyposensitization of normal greyhounds with irrelevant aqueous antigens, administered according to one treatment schedule recommended following ELISA allergy testing, did not appear to cause false positive reactions on subsequent intradermal allergy tests or to induce clinical hypersensitivity. Further studies are required to determine if hypersensitivity to irrelevant antigens is induced in atopic dogs following hyposensitization with nonaqueous extracts or higher concentrations of aqueous antigens. Résumé— Cinq Greyhound sains ont été utilisés pour étudier l'hypersensibilitéà des pollens, des moisissures des arbres et des herbacées en utilisant des intradermoréactions et des tests ELISA du commerce. Tous les animaux ont été désensibilisés pendant 6 mois avec le même mélange de 14 allergènes, en suivant le protocole recommandé par le laboratoire qui commercialise le test ELISA. Après hyposensibilisation à ces antigènes à une concentration de 1/200 p/v, les chiens ont été réévalués par des intradermoréactions. Aucune différence signifaicative avant et après traitement n'a été notée et tous les chiens sont restés asymptomatiques durant la période de l'essai. L'hyposensibilisation chez des Greyhounds sains avec des antigènes auxquels ils ne sont pas sensibles, en suivant le protocole recommandé par la laboratoire producteur, ne semble pas entrainer de fausses réactions intradermiques positives ni une hypersensibilité clinique. D'autres études sont nécessaires pour savour si cette sensibilisation peut être induite chez des animaux atopiques, avec des extraits non aqueux et à de plus fortes concentrations. Zusammenfassung— Fünf gesunde Greyhounds wurden uaf allergische Reaktionen gegenüber verschiedenen Gräsern, Unkräutern, Bäumen und Pilzen sowohl mit einem Intradermaltest als auch mit einem kommerziellen ELISA-Test getestet. Alle Hunde wurden über 6 Monate mit derselben Mischung aus 14 Allergenen “desensibilisiert”. Hierzu wurde ein Therapieschema verwendet, das von dem Labor, das den ELISA-Test durchgeführt hatte, empfohlen worden war. Nach der “Desensibilisierung” mit nicht relevanten Allergenen in einer Konzentration von 1:200 w/v wurden die Hunde erneut mit einem Intradermaltest getestet. Nach der “Desensibilisierung”über sechs Monate gab es keinen signifikanten Anstieg bei den intradermalen Reaktionen. Alle Hunde blieben währen der Untersuchungszeit symptomfrie. “Desensibilisierung” von gesunden Greyhounds mit nicht relevanten wäßrigen Antigenen, die nach dem empfohlenen Therapieschema nach einem ELISA-Allergietest angewendet worden waren, schienen keine falsch-positiven Reaktionen im nachfolgenden Intradermaltest hervorzurufen und keine klinische Allergie auszulösen. Weitere Untersuchungen sind erforderlich, urn zu klären, ob eine Allergie gegenüber nicht relevanten Antigenen bei atopischen Hunden nach Desensibilisierung mit wäßrigen Extrakten order mit höheren Konzentrationen von wäßrigen Allergenen induziert werden kann. Resumen Cinco perros galgos de apariencia clínica normal, se evaluaron con tests de alergia a varias hierbas, árboles y hongos, por medio de inyecciones intradérmicas y también con ensayos comerciales de enzima de inmunoabsorbencia ligada (ELISA). A todos los perros se les admistró tratamiento de hiposensitización por un curso de 6 meses con una mezcla de 14 alergenos, según el protocolo recomendado por el laboratorio comercial proveedores del test ELISA. Después del tratamiento inmunosupresivo con una concentración de antígenos irrelevantes de 1:200 w/v, los animales se volvieron a evaluar por medio del test de inyecciones intradérmicas. Después de 6 meses de terapia inmunosupresiva no se observaron cambios significativos en las reacciones cutáneas, y todos los animales permanecieron asintomaticos durante el periodo de estudio. El tratamiento inmunosupresivo de perros galgos con antígenos en solución acuosa administrados de acuerdo con el protocolo recomendado después del test ELISA, no produjo reacciones falsas positivas en tests intradérmicos posteriores, o reacciones de hipersensitividad alguna. Para determinar si la posibilidad de hipersensitividad con antígenos irrelevantes es inducida en perros que padecen atopia después del tratamiento inmunosupresivo con extractos antigénicos de tipo no acuoso, o mayores concentraciones de antígenos acuosos, más investigaciones son necesarias.     

Effect of Caudal Traction on Mechanical Nociceptive Thresholds of Epaxial and Pelvic Musculature on a Group of Horses With Signs of Back Pain

Direct muscular attachment from lumbar vertebrae to the caudal vertebrae of the tail suggests that caudal traction, also described as a tail pull, may affect lumbar vertebral segments and/or associated soft tissues in horses. Traction is a commonly used human manual therapy technique used for pain relief and anecdotally observed to relieve pain in horses. However, research is lacking validating the efficacy of manual caudal traction on the horse. The objective of this study was to determine if caudal traction has an effect on mechanical nociceptive thresholds (MNTs) in a group of horses with clinical signs of back pain. Pressure algometry was used to measure MNTs of five bilateral anatomical sites in the epaxial and pelvic musculature of 11 horses referred to physiotherapy because of clinical signs of back pain. Measurements were recorded both before and immediately after traction. A significant difference (P ≤ .05) was identified between mean before and after caudal traction algometry measurements in all described sites. The percentage of MNT increase was highest in the thoracic region (83%) compared with the lumbar (50%) and the pelvic (52.4%) regions. These results support an effect of caudal traction in increasing MNTs in the thoracolumbar and pelvic regions in horses. Further research to determine the clinical effect of this technique is warranted.     

Dorsal Nerve Root Origins of the Cutaneous Nerves of the Feline Pelvic Limb

The dorsal root origins of cutaneous nerves supplying the feline pelvic limb were determined electrophysiologically in 11 cats. Cutaneous nerves were surgically exposed and the presence or absence of an evoked potential in response to stimulation of individual dorsal roots was noted. The dorsal cutaneous branches of L3-L5 and S3, and the lateral cutaneous branch of L3 each arose solely from their parent spinal nerves. The L7, S1, and S2 dorsal cutaneous branches had multiple dorsal root origins. The lateral cutaneous femoral nerve originated from L3-L6 dorsal roots in 4 patterns of origin, and the saphenous nerve originated from L4-L6 dorsal roots in 2 patterns of origin. The lateral and caudal cutaneous sural nerves originated from L6-S1 roots in 2 and 3 patterns, respectively. The lateral and medial plantar nerves arose from L6-S2 roots in 4 and 2 patterns, respectively. The superficial and deep peroneal nerves originated from L6-S1 roots in 2 and 3 patterns, respectively. The caudal cutaneous femoral nerve or its branches arose from L7-S3 in 8 origin patterns. The dorsal nerve of the penis and the superficial perineal nerve arose from L7-S3 and S1-S3 roots, respectively, each in 4 patterns. A subtle correlation between plexus type and dorsal root origins of the cutaneous nerves was noted.     

A Temporal Study Comparing the Carriage of Staphylococcus intermedius on Normal Dogs with Atopic Dogs in Clinical Remission

Résumé— Le portage de Staphylococcus intermedius dans les narines, le pourtour anal et la ligne blanche a été compare chez 10 chiens sains et 19 chiens atopiques cliniquement controlés, recevant de faibles doses, à jours alternés, de prednisone pendant une période six mois. Un test du x² n'a pas permis de mettre en évidence une différence significative du taux d'isolement de S. intermedius entre les deux groupes en aucune localisation ni en regroupant l'ensemble des localisations [Harvey, R. G., Noble, W. C. A temporal study comparing the carriage of Saphylococcus intermedius on normal dogs with atopic dogs in clinical remission (Etue comparative du portage de Staphylococcus intermedius chez les chiens sains et atopiques cliniquement guéris).
Abstract— A temporal study of the carriage of Staphylococcus intermedius from the nares, anal ring and ventral midline of 10 normal dogs was compared to that of 19 atopic dogs receiving low dose, alternate-day prednisolone over a period of six months and maintained in clinical remission.
Chi-squared comparison of the two groups revealed no difference between the groups in the recovery rate of S. intermedius at any single site and no significant difference when all sites were pooled.     

The Effect of Acute, Unilateral Transverse Venous Sinus Occlusion on Intracranial Pressure in Normal Dogs

Lateral rostrotentorial and caudal suboccipital approaches to the brain were performed on six beagles. Intracranial pressure (ICP) was measured as the two craniectomies were connected by removing the bone of the nuchal crest and occluding the transverse venous sinus. Intracranial pressure remained constant after acute occlusion of the sinus with bone wax and there was no gross evidence of brain edema. All six dogs survived the surgery and five dogs survived for a minimum of 3 months. One dog died acutely during the postoperative period. The exact cause of the cerebellar hemorrhage and infarction found at necropsy in the latter dog was not evident. Anemia occurred in three of the six dogs as a result of intraoperative hemorrhage. All dogs surviving the perioperative period had mild, transient hypermetria and conscious proprioceptive deficits, but were neurologically normal 72 hours after surgery. Results of this study indicate that acute, unilateral transverse sinus occlusion is possible without an increase in ICP. The ability to do this allows access to the rostral aspect of the ipsilateral cerebellum and brain stem.