Thyroid testing in Sloughis

Background: Thyroid hormone concentrations were found to be different in Greyhounds and Whippets compared with nonsight hound dogs.
Hypothesis: In Sloughis, thyroid hormone concentration is lower than in nonsight hounds and comparable to Greyhounds.
Animals: Fifty-one Sloughis with no evidence of disease and a mean age of 4 years (range, 1–12 years).
Methods: Thyroid profiles consisting of total thyroxine (tT4), free thyroxine (fT4), free thyroxine after equilibrium dialysis (fT4 after ED), canine thyroid stimulation hormone (cTSH), and thyroglobulin antibodies as well as CBC and serum biochemistry results of Sloughis were compared with those of normal dogs. In 8 Sloughis, TSH stimulation tests were performed.
Results: In Sloughis, tT4 concentrations and fT4 concentrations measured by chemiluminescence were lower than those of controls (1.13 ± 0.65 μg/dL compared with 2.9 ± 0.8 μg/dL, P < .0001 and 11 ± 4.3 pmol/L compared with 16.7 ± 5.2 pmol/L, P < .0001, respectively). Concentrations of fT4 after ED and TSH were increased in Sloughis, when compared with controls (41.3 ± 26.9 pmol/L compared with 20.98 ± 10.29 pmol/L, P < .0001 and 0.22 ± 0.15 pmol/L compared with 0.15 ± 0.13 pmol/L, P = .0138, respectively). T4 concentration after TSH stimulation increased from 1.5 μg/dL (range, 0.2–2.7 μg/dL) to 2.7 μg/dL (range, 1.2–4.7 μg/dL); the recommended post-TSH T4 concentration was achieved by only 3 of 8 Sloughis. Hemoconcentration was found in 84.3% and hypoglobulinemia in 80.3%.
Conclusions and Clinical Importance: When evaluating Sloughis for hypothyroidism, veterinarians should be aware that these dogs have different thyroid hormone concentrations than nonsight hound dogs.     

Seroprevalence of babesiosis in Greyhounds in Florida.

An indirect fluorescent antibody test was used to serologically survey Greyhounds from 10 kennels that are part of the racing Greyhound industry in Florida. Age of dogs ranged from 11 months to 11 years. Additionally, 50 adult non-Greyhound pet dogs were consecutively surveyed. Of 393 Greyhounds tested, 181 (46%) were seropositive for babesiosis; pet dogs were seronegative. Slightly higher percentage of seropositive males than females was observed, but this difference was only significant (P less than 0.01) in the 2- to 5-year age class. Male dogs less than 2 years old had significantly (P less than 0.01) lower seroprevalence than did male dogs greater than 2 years old. All 46 Greyhounds that were actively racing at the time of sample collection were seronegative. Dogs were classified into 2 groups on the basis of whether the kennel owner had sought veterinary attention for anemic pups. The 5 kennel owners that had sought veterinary attention (group A) had significantly (P less than 0.01) higher seroprevalence (78.5%), compared with the 5 that had not sought veterinary attention (group B; 23.0%). Seroprevalence of babesiosis in Greyhounds in Florida was comparable to that reported in a limited survey of other southeastern states. It appears to be higher than that in the pet population. Breeding kennels in Florida and other southeastern states from which anemic pups originate should be screened for babesiosis.     

Pharmacokinetics of subcutaneous fentanyl in Greyhounds

The purpose of the study was to describe the pharmacokinetics of subcutaneous fentanyl (15μg/kg) in six healthy Greyhound dogs. Fentanyl plasma concentrations were determined by a liquid chromatography with mass spectrometry method. Non-compartmental pharmacokinetic analysis was used. Fentanyl was rapidly absorbed with a mean peak concentration (C(MAX)) of 3.56ng/mL at 0.24h. The mean terminal half-life, volume of distribution per bioavailability, and clearance per bioavailability were 2.97h, 7.09L/kg, 27.60mL/min/kg, respectively. Pain occurred on injection in all six dogs, but addition of 8.4% sodium bicarbonate (1mL per 20mL fentanyl) resulted in no pain on injection in 3/3 dogs but similar C(MAX) values. The subcutaneous route may be an alternative route of fentanyl administration if intravenous administration is not practical.     

Serum protein electrophoresis in retired racing Greyhounds

BACKGROUND: Retired racing Greyhounds are becoming common as pets. Because of their unique physiology, results of routine laboratory tests are frequently outside the reference interval for dogs. Compared with other breeds, Greyhounds have low serum protein concentrations, but the concentrations of different serum protein fractions have not been reported. OBJECTIVES: Our objectives were to evaluate the results of serum protein electrophoresis (SPE) in healthy, retired racing Greyhounds and compare them with a control group of age- and gender-matched non-Greyhound dogs. METHODS: Agarose gel electrophoresis was done using a standard method; the gels were stained with amido black and scanned with a Cliniscan 2 densitometer (Helena Laboratories, Beaumont, TX, USA). Protein fractions were identified by visual inspection of the electrophoretogram. A Student's t-test assuming equal variances was used to compare the concentration of the different fractions between groups. RESULTS: The concentrations of total protein, total globulins, and alpha-1-, alpha-2-, beta-1-, and beta-2-globulins were significantly lower and the albumin to globulin (A:G) ratio was significantly higher in Greyhounds than in non-Greyhound dogs (P < .05). There was no significant difference in albumin or gamma-globulin concentrations. CONCLUSIONS: Low serum protein concentrations in Greyhounds are the result of low concentrations of a- and b-globulins. These results should be kept in mind when evaluating both healthy and sick Greyhounds. Additional studies are needed to identify the individual proteins associated with low alpha- and beta-globulin concentrations in Greyhounds.     

Fractures of the Calcaneus in Racing Greyhounds

Fifty-one calcaneus fractures associated with (41) or without (10) central tarsal bone (Tc) fractures in racing greyhounds were evaluated and categorized. All calcaneal fractures with no Tc fractures had a plantar proximal intertarsal subluxation. No subluxations were found in dogs with both calcaneal and central tarsal fractures. The calcaneal fractures were treated either with coaptation splints or surgical repair. Surgical techniques included a Steinmann pin with a figure eight tension band device or screw or plate fixation as primary techniques supplemented by Kirschner wires and cerclage wires. In all calcaneal fractures associated with plantar proximal intertarsal subluxation, an arthrodesis of the calcaneoquartal joint was performed. All 22 surgically repaired fractures in dogs available for physical and radiographic reexamination had healed within 1 to 6 months. Eight dogs with fractures of the calcaneus associated with fractures of Tc returned to a racing career. None of the dogs with plantar proximal intertarsal subluxation raced again. Based on the orientation of the fracture lines and on dissection of two tarsi with calcaneal fractures, a hypothesis on the pathogenesis of calcaneal fractures in racing greyhounds was formulated.     

Airway physiology and clinical function testing.

The advent of pulmonary function testing in small animals has opened the door to new interpretations of old diseases. This article reviews the salient features of airway pathophysiology in dogs and cats that relate to the interpretation of newly developed airway function tests.     

Clinical pulmonary function testing in dogs and cats.

Pulmonary function testing is a relatively new area in clinical veterinary medicine, with few individuals currently obtaining TBFVL and pulmonary mechanics on a clinical cases of respiratory disease in dogs and cats. ABG analysis is a technique available to all veterinarians through commercial laboratories or local hospitals. Information obtained from these tests will allow for a better understanding of the pathophysiology of naturally occurring diseases as well as assisting in the determination of the efficacy of various therapeutic agents (such as bronchodilators), which to date has been lacking in veterinary medicine.     

Thyroid function and pregnancy status in broodmares

OBJECTIVE: To determine whether thyroid function was associated with pregnancy status in broodmares. DESIGN: Prospective study. ANIMALS: 79 Thoroughbred and Standardbred broodmares between 2 and 22 years old. PROCEDURE: Serum triiodothyronine (T3) concentration was measured before and 2 hours after i.v. administration of thyrotropin releasing hormone (TRH), and serum thyroxine (T4) concentration was measured before and 4 hours after TRH administration. Pregnancy status was monitored by means of transrectal ultrasonography beginning 16 days after ovulation. RESULTS: Baseline T3 and T4 concentrations varied widely. In all mares, serumT3 concentration increased in response to TRH administration. Serum T4 concentration increased in response toTRH administration in all but 2 mares. Pregnancy rate was 76%. Baseline and stimulated serum T3 and T4 concentrations were not significantly different between mares that became pregnant and those that did not. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that decreased thyroid function is uncommon in mares and poor thyroid function is not a common cause of infertility. Thus, the practice of indiscriminately treating broodmares with thyroid hormone to enhance fertility appears questionable at this time.     

Hematologic values in young pretraining healthy Greyhounds

BACKGROUND: Greyhound dogs have numerous clinicopathologic differences compared with other dog breeds, most notably in their hematologic profiles. The hematologic differences are likely related to breed; however, the influence of other factors, including age, sex, and training, has not been fully determined. OBJECTIVES: The aim of this study was to assess hematologic values in young, healthy, pretraining Greyhounds and to determine the effects of age and sex on these findings. METHODS: Jugular venous EDTA-anticoagulated blood samples were collected from 43 healthy, pretraining Greyhounds between 5 and 13 months of age. Samples were analyzed within 24 hours of collection on an Abbott CELL-DYN 3500R hematology analyzer. Mean hematologic results for different age groups, and correlation with age and sex were determined for each analyte. Results were compared with adult canine, nonbreed-specific reference intervals. RESULTS: From the age of 9 to 10 months, Greyhounds had higher HCT, hemoglobin concentration, and RBC counts compared with adult canine reference intervals. Younger Greyhounds (5-6 months) had values comparable with reference intervals. Mean total WBC, neutrophil, lymphocyte, and platelet counts tended to be toward the lower end or below the reference intervals. HCT, hemoglobin concentration, and RBC counts were correlated positively with age, and platelet count was correlated negatively with age. No differences were found based on sex. CONCLUSIONS: These results confirm that significant hematologic differences exist in pretraining Greyhounds by 9 to 10 months of age, when compared with adult canine, nonbreed-specific reference intervals; however, these differences are less marked in Greyhounds 5 to 6 months old. Given these findings, it is unlikely that factors such as training or racing are responsible for differences in hematologic values between adult Greyhounds and other breeds.     

Thyroid function in dogs with spontaneous and induced congestive heart failure.

The effects of spontaneous and experimentally induced congestive heart failure on serum thyroxine (T4), 3,5,3'-triiodothyronine (T3), 3,3'5'-triiodothyronine (reverse T3), free T4, free T3 concentrations, and the serum T4 and T3 concentrations in response to administration of thyrotropin were studied. Serum thyroid hormone concentrations were not different between eight dogs with spontaneous congestive heart failure and normal age matched control dogs. Seven dogs with experimental heart failure were tested before and after induction of congestive heart failure by rapid ventricular pacing. Mean serum T4 and free T3 concentrations were decreased and mean serum reverse T3 concentration was increased following induction of heart failure. The serum T4 and T3 responses to thyrotropin were not altered. Thyroid gland morphology appeared normal in dogs with experimental heart failure. Experimental congestive heart failure, similar to some other nonthyroidal illnesses, alters thyroid hormone secretion and metabolism in dogs.     

Some observations on behaviour of Greyhounds

A full account, based on personal experience, is given of the ethological aspects of the life of a Greyhound during puppyhood, training and on the course. Résumé. Un compte rendu complet, basé sur des expériences personnelles, est donné des aspects éthologiques de la vie d'un lévrier pendant sa jeunesse, son dressage et sur la piste. Zusammenfassung. Ein vollständiger Bericht, auf persönliche Erfahrung begründet, über die ethologischen Aspekte eines Windhundes, als Welpe, im Training und im Rennen, ist erstattet.     

Serum creatinine concentrations in retired racing Greyhounds

Background: Greyhounds frequently have laboratory values that are outside reference intervals established for dogs. Our recognition of increased serum creatinine concentrations in several Greyhounds posed a problem when evaluating a Greyhound with suspected renal disease.
Objective: The purpose of this study was to compare serum creatinine concentrations between Greyhound and non-Greyhound dogs.
Methods: Thirty retired racing Greyhounds and 30 age-and gender-matched control non-Greyhound dogs were evaluated. Serum creatinine concentrations in both groups were measured using a standard biochemical method and compared statistically using a Kruskal-Wallis test.
Results: Creatinine concentration was significantly higher in the Greyhounds ( P < .01) than in the control group.
Conclusion: Greyhounds have a higher serum creatinine concentration than do non-Greyhound dogs. This idiosyncrasy should be taken into account when evaluating healthy Greyhounds and those with suspected renal disease.     

Thyroid function tests in dogs using radioimmunoassay kits

Thyroid function has been assessed using radioimmunoassay kits for total and free thyroxine (T4). A radioimmunoassay kit for total T4, designed for human samples, was unable to detect total T4 in 35 per cent of normal canine serum tested, due to the kit being designed to measure total T4 over the normal human range which is four times the canine normal range. The canine normal range for free T4 (7.5–50 pmol/1) was found to be of the same order as the human range and therefore a free T4 kit was suitable for measuring the free hormone in dogs. In response to thyroid stimulating hormone in normal dogs, total T4 rose 6.2 times whereas free T4 rose only 2.6 times. Hypothyroid animals could be distinguished from normal dogs by free T4 assay whereas they were indistinguishable from many normal dogs by total T4 assay. Response to thyroid stimulating hormone was used to confirm hypothyroidism, but also revealed one animal with normal total and free T4 but which had a negligible response on stimulation.