Ultrasonographic evaluation of the thyroid gland in healthy, hypothyroid, and euthyroid Golden Retrievers with nonthyroidal illness

Ultrasound evaluation of the thyroid gland was performed in healthy, hypothyroid, and euthyroid Golden Retriever dogs with nonthyroidal illness (NTI) to determine the diagnostic usefulness of ultrasound for differentiating between euthyroid and hypothyroid dogs. Thirty-six healthy, 11 hypothyroid, and 35 euthyroid dogs with NTI were evaluated. Each thyroid lobe was examined ultrasonographically for size, shape, echogenicity, and homogeneity. Thyroid lobe volume was estimated by using the equation for an ellipsoid: pi/6(length X height x width). No differences were found between healthy dogs and euthyroid dogs with NTI. In the majority of euthyroid dogs, the thyroid lobes were fusiform and triangular in shape in longitudinal and transverse planes, respectively. The thyroid capsule appeared smooth. The thyroid parenchyma had a homogeneous echogenic pattern and usually was hyperechoic or isoechoic compared with the surrounding musculature. Ultrasound findings in hypothyroid dogs were more variable, including a greater frequency of round to oval-shaped thyroid lobes in the transverse imaging plane (P < .05), hypoechogenicity of the thyroid parenchyma compared with surrounding musculature (P < .001), and a decrease in the size and volume of the thyroid lobes and total volume of the thyroid gland (P < .05) compared with euthyroid dogs. Other findings in hypothyroid dogs included an irregular surface to the thyroid capsule, a heterogeneous pattern to the thyroid parenchyma, and differences in the echogenic pattern between the left and right thyroid lobes. Results suggest that determination of thyroid size and volume by ultrasound may be a useful adjunctive test for differentiating between hypothyroid and euthyroid dogs with NTI.     

Normal Canine Prostate Gland: Repeatability,Reproducibility, Observer‐Dependent Variability of Ultrasonographic Measurements of the Prostate in Healthy Intact Beagles

Most prostatic diseases in dogs are associated with prostatomegaly, and transabdominal ultrasonography has become the imaging modality of choice for evaluation of the prostate gland in the dog. The aim of the present study was to assess the reproducibility, the repeatability and interobserver variations of sonographic measurements of prostate and to determine which measurement had the lowest variability. Length and height of prostate gland were measured on longitudinal views, width of the prostate gland and height of left and right lobes of the gland on transversal views. The within‐day and between‐day variabilities of the prostatic parameters were determined by performing 1350 (270 length, 270 height, 270 width, 270 height of right lobe and 270 height of left lobe) examinations on ten healthy intact beagle dogs on six different days, in a two‐week period (three days for the five dogs, three different days for the five others). Three observers with different levels of experience in ultrasonography performed the examinations. The lowest within‐day and between‐day standard deviation and coefficient of variation values were observed for the width of the prostate. The width of the gland measured on transverse frozen images seems to be the most reliable measurement for evaluating size of prostate glands in healthy dogs, although the shape, position, outline, and echogenicity of the prostate should also be assessed.     

ULTRASONOGRAPHIC EXAMINATION OF THE THYROID GLAND OF HYPERTHYROID CATS: COMPARISON TO 99mTcO−4 SCINTIGRAPHY

High-resolution ultrasonography was evaluated as an alternative to ^99mTcO^-₄ scintigraphy for examining size and appearance of thyroid glands in hyperthyroid cats. Thyroid ultrasound examinations were performed on 6 normal cats and 14 cats with hyperthyroidism. Thyroid lobe volume was estimated from ultrasound images using the equation for a prolate ellipsoid, π/6 (length * height * width). Total thyroid volume was estimated by adding the volume estimations of the left and right lobes. Thyroid lobes of hyperthyroid cats were considered abnormal if estimated volume exceeded the 99% confidence interval for normal thyroid volume determined from the control group. Scintigraphic examinations performed on hyperthyroid cats were evaluated for unilateral versus bilateral disease and for the presence of ectopic activity. Mean thyroid lobe volume and total thyroid volume for normal cats was 85 and 169 mm³, respectively. Mean thyroid lobe volume and total thyroid volume for hyperthyroid cats was 578 and 889 mm³. There was a significant difference in mean estimated total thyroid volume of normal and hyperthyroid cats. Thyroid lobes with greater than normal TcO^-₄ uptake on scintigraphy were larger and had variable homogeneity, echogenicity, and margination on ultrasound examination. There also was an 85.7% agreement of scintigraphy and ultrasonography in differentiating normal from abnormal thyroid lobes. A fair correlation between estimated total thyroid volume of hyperthyroid cats and most recent pretherapy serum thyroxine values were also found. This preliminary study indicates that thyroid ultrasound examination may provide information that is useful for diagnosis and treatment of feline hyperthyroidism. Although ultrasound provides accurate evaluation of the thyroid glands, it cannot replace ^99mTcO^-₄ scintigraphy for screening of metastatic lesions and ectopic glands.     

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.     

Do Thyroid Ultrasonographic Features Change According to Age in Euthyroid Dogs?

The thyroid gland was assessed by ultrasound in healthy euthyroid mixed‐breed medium size dogs in different age groups. The objective was to verify ultrasonographic imaging patterns in these groups, as well as to identify possible changes in imaging features resulting from ageing. Thirty dogs – 10 young (<1 year), 10 adult and 10 elderly – without clinical signs or history of thyroid gland disease with complete blood count and thyroid function tests within the reference values were evaluated. Each thyroid lobe was examined by ultrasound for shape, size, echogenicity and echotexture. The analysis of echogenicity and echotexture was made by histogram. Thyroid volume was estimated by the equation for ellipsoid (length × width × height) π/6. The thyroid volume of the young dogs in this study had a tendency to be higher than in adult dogs (P = 0.068) and older dogs (P = 0.120). The height of the thyroid lobe in the longitudinal plane was significantly higher (P = 0.026) in young dogs compared with the other dogs. The echotexture and echogenicity had no significant differences between groups, but the echogenicity was greater in older dogs. The results point out that ultrasound imaging of the thyroid volume is influenced by age in euthyroid dogs.     

SHORT‐TERM EFFECT OF RECOMBINANT HUMAN THYROID‐STIMULATING HORMONE ON THYROID VOLUME AND ECHOGENICITY IN HEALTHY BEAGLES

In humans, administration of recombinant human thyroid stimulating hormone (rhTSH) allows radioactive iodine dose reduction and higher efficacy in the treatment of multinodular goiter and thyroid cancer. A similar effect might be expected in dogs with thyroid carcinoma. However, if rhTSH leads to an increase in thyroid volume, it must be used carefully in dogs with large thyroid tumors to avoid compression of key anatomical structures. The aim of this study was to determine the short‐term effect of rhTSH on thyroid volume and echogenicity, measured by ultrasonography, in healthy Beagles. Seven beagles were divided randomly in two groups in a prospective placebo‐controlled blinded cross‐over study. On day 1, one group received 100 μg of rhTSH intravenously and the other group received placebo. After a wash‐out period of 3 weeks, the groups were crossed over. Evaluation of thyroid echogenicity, homogeneity, shape, capsule delineation, and measurement of thyroid length, width, and height were performed by the same observer at baseline, and at 6, 24, and 48 h after injection of rhTSH and placebo. There was no significant difference between the effect of rhTSH and placebo on thyroid volume (P=0.397), echogenicity, homogeneity, or capsule delineation. Time had a significant effect on thyroid volume (P=0.027). No adverse effects after rhTSH administration were noticed. The effect of rhTSH on thyroid volume in dogs with thyroid carcinoma needs to be assessed.     

Use of helical computed tomography for measurement of thyroid glands in clinically normal cats

OBJECTIVE: To determine the dimensions and volume of thyroid tissue in clinically normal cats by use of computed tomography. ANIMALS: 8 cats. PROCEDURE: Helical computed tomography images (2-mm collimation) were acquired from the cranial aspect of the second cervical vertebra through the caudal aspect of the fourth cervical vertebra. Data were acquired before contrast medium administration (n = 7 cats) and immediately after contrast medium enhancement (1 cat). Length, width, and height measurements of each thyroid lobe were made by use of transverse, dorsal, and sagittal plane images. Thyroid lobe volume was estimated by use of 3 methods. RESULTS: All thyroid lobes were histologically normal. Mean dimensions for a thyroid lobe were 16.5 x 2.00 x 4.31 mm (length x width x height) using only data from transverse images. Mean thyroid lobar volume was 113.75 mm(3) using the sum of areas method. Mean total volume of thyroid tissue was 215.25 mm(3) using the sum of areas method. CONCLUSIONS AND CLINICAL RELEVANCE: Results may be useful for computed tomography evaluation of abnormal thyroid glands in cats, which warrants investigation.     

Concentrations of Prolactin, LH, Testosterone, TSH and Thyroxine in Normospermic Dogs of Different Breeds

Concentrations of prolactin (PRL), LH, testosterone (T), TSH and thyroxine (T₄) were determined before and at 20, 120 and 180 min after a single iv injection of thyrotropin-releasing hormone (TRH) in eight Beagles, eight Fox Terriers, six Labrador Retrievers and five Great Danes that were normospermic. Mean basal PRL concentrations were lower in the Fox Terriers compared with the Great Danes (p < 0.05). Mean LH concentrations were higher in the Fox Terriers than in the Beagles, and T was lower in the Fox Terriers at some times but not others (p < 0.05). Thyroid Stimulating Hormone (TSH) concentrations did not differ among breeds, while mean basal T₄ values were lower in Fox Terriers compared with Labrador Retrievers and Great Danes (p < 0.05). Stimulation of T₄ secretion 120 and 180 min after iv TRH injection was most pronounced in the Beagles and less in the Fox Terriers (p < 0.05). The results of the present study indicate that potential breed differences in circulating concentrations of PRL, LH, T, TSH and T₄ in male dogs with apparently normal fertility can be encountered, but further studies are needed to determine whether the observed differences are typical features of these breeds, reflect subsets of dogs within breeds, or are in part because of possible uncontrolled parameters such as sample timing, ambient photoperiod, housing conditions or diet.     

Breed distribution of dogs with diabetes mellitus admitted to a tertiary care facility

OBJECTIVE: To determine which dog breeds are at low and high risk for developing diabetes mellitus (DM). DESIGN: Cohort study. ANIMALS: Hospital population of 221 dogs with DM and 42,882 dogs without DM during 5.5 years. PROCEDURE: 165 breeds (including a mixed-breed category) were represented in the hospital population. Breed-specific expected numbers of dogs with DM were calculated by multiplying the proportion of all dogs admitted to the hospital that were determined to have DM during the study period by the breed-specific totals during the study period. Breeds or breed groups evaluated in the analysis (n = 20) were restricted to those that had a combined observed and expected count > 5 to document breeds at low and high risk for developing DM. Proportionate changes in the risk of developing DM by breed were calculated and presented using exact odds ratios, 95% confidence intervals, and P values. Mixed-breed dogs were chosen as the reference breed. RESULTS: Samoyeds, Miniature Schnauzers, Miniature Poodles, Pugs, and Toy Poodles were at high risk for developing DM. Dog breeds found to be at low risk for developing DM were German Shepherd Dog, Golden Retriever, and American Pit Bull Terrier. CONCLUSION AND CLINICAL RELEVANCE: The finding that certain dog breeds are at low or high risk for developing DM suggests that some genetic defects may predispose dogs to development of DM, whereas other genetic factors may protect dogs from development of DM.     

Computed tomographic features of the normal canine thyroid gland.

The computed tomographic (CT) features of the normal thyroid gland were compiled from images acquired in 25 client-owned dogs without thyroid gland disease. The mean pre- and postcontrast attenuation values were 107.5 and 169.0 Hounsfield Units, respectively. After injection of intravenous contrast medium (600 mg iodine/kg), the apparent thyroid gland volume (both lobes combined) increased from a mean value of 1148.0 nm3 to a mean value of 1188.9 mm3. All thyroid lobes were homogeneous on pre- and postcontrast images. In a craniocaudal direction, the gland spanned a region from the 1st to the 8th tracheal ring and the right lobe was often more cranial than the left. On transverse images the lobe shape was ovoid in 72%, and its location was dorsolateral to the trachea in 90% of dogs. Parathyroid glands could not be identified and an isthmus connecting both thyroid lobes was only seen in one dog. Considering the excellent visibility of the normal canine thyroid gland, CT can be beneficial in the differentiation of thyroidal versus nonthyroidal neck masses. CT also yields potential in the staging of thyroid carcinomas.     

Heritabilities and genetic trends for elbow score as recorded by the New Zealand Veterinary Association Elbow Dysplasia Scheme (1992–2013) in four breeds of dog

AIM: To estimate the heritability of the New Zealand Veterinary Association (NZVA) elbow phenotype, obtain estimated breeding values (EBV) for the worst-elbow score and estimate the genetic trends for this trait in four populous breeds of dogs, using the records from the NZVA Canine Elbow Dysplasia Scheme database (1992–2013).

METHODS: Overall, 4,070 elbow records from a pedigree of 11,311 dogs were available for animals scored between 1992 and 2013. The worst elbow score between the left and right elbows was identified for each dog and used for EBV analysis. Estimates of heritability and EBV for the elbow score of dogs from German Shepherd dog, Labrador Retriever, Golden Retriever and Rottweiler breeds were obtained using restricted maximum likelihood procedures with a within-breed linear animal model. The model included the fixed effects of sex and birth year, with age at scoring as a covariable, and the random effect of animal. Genetic trends for the worst-elbow score were calculated as the regression coefficient of the EBV, weighted by reliabilities, on year of birth.

RESULTS: The estimates of heritability for worst-elbow score were 0.25 (SE 0.06) in German Shepherd dogs, 0.46 (SE 0.06) in Labrador Retrievers, 0.18 (SE 0.07) in Golden Retrievers and 0.29 (SE 0.11) in Rottweilers. The genetic trend for German Shepherd dogs was ?0.0082 (SE 0.0015), for Labrador Retrievers was ?0.0016 (SE 0.0016), for Golden Retrievers was ?0.0033 (SE 0.0010) and for Rottweilers was ?0.0070 (SE 0.0023) units per annum, which were different from zero (p<0.01) in all breeds except Labrador Retrievers.

CONCLUSIONS AND CLINICAL RELEVANCE: A small but favourable response to selection was achieved by three of the four breeds in the study period; during which selection for elbow traits has been largely voluntary. While the magnitude of genetic change in terms of elbow units per annum may appear small, it must be remembered that elbow scoring grades only range from 0–3. Greater improvement may be possible if compulsory screening was a requirement for pedigree breeding stock, and if greater selection pressure were applied on the basis on an individual’s EBV, rather than the worst-elbow score alone. The maintenance of an open registry, with transparency of EBV information made available to all breeders, may enhance selection intensity opportunities and potentially assist with the process and progress of breeding selection.     

Evaluation of results for Schirmer tear tests conducted with and without application of a topical anesthetic in clinically normal dogs of 5 breeds

OBJECTIVE: To evaluate, for clinically normal dogs, results of Schirmer tear tests in eyes without topical anesthetic (STT) and to detect differences associated with breed, sex, age, day, and time of day in eyes in which STT was performed after use of topical anesthetic (STTa). ANIMALS: 41 Beagles, 43 Labrador Retrievers, 25 Golden Retrievers, 26 English Springer Spaniels, and 22 Shetland Sheepdogs. PROCEDURE: Beagles had STT and STTa values measured twice daily for 5 days. Client-owned dogs of 4 other breeds had STT and STTa values measured once. RESULTS: Mean +/- SD values of Beagles for STT and STTa were 20.2 +/- 2.5 and 3.8 +/- 2.7 mm/min. Mean values for STT and STTa were as follows: Labrador Retriever, 22.9 +/- 4.1 and 9.6 +/- 3.8 mm/min; English Springer Spaniel; 20.7 +/- 3.2 and 5.4 +/- 3.4 mm/min; Golden Retriever, 21.8 + 3.7 and 8.8 +/- 3.1 mm/min; and Shetland Sheepdog, 15.8 +/- 1.8 and 3.6 +/- 2.8 mm/min. Overall mean values for STT and STTa were 20.2 +/- 3.0 and 6.2 +/- 3.1 mm/min. Differences for STT and STTa were detected among breeds, but significant differences were not associated with sex or age within each breed or in overall values for all dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Results for the STT reported here compare favorably with reported values, except for results of Shetland Sheepdogs; however, results for the STTa differ dramatically from reported values. Clinicians should consider effects attributable to breed when evaluating results of STT and STTa in dogs.     

Canine parentage testing based on microsatellite polymorphisms.

To establish an accurate method for parentage testing in dogs, microsatellite DNA repeat length polymorphisms were examined. We selected twenty microsatellite markers reported previously and examined their application for parentage testing in Beagles and Labrador Retrievers. Heterozygosity (He), Polymorphism Information Content (PIC), the probabilities of Paternity Exclusion (PE) and the combined PE were calculated from allelic frequencies of the markers. All markers amplified by polymerase chain reactions were polymorphic and many markers showed high He and PIC in the both breeds. The final combined PEs in Beagles and Labrador Retrievers were 0.999994 and 0.999920, respectively. The results suggest that the twenty markers can be applied for routine parentage testing in dogs.     

Ultrasonographic Adrenal Gland Measurements in Healthy Yorkshire Terriers and Labrador Retrievers

An upper threshold of 7.4 mm for maximal adrenal gland diameter is commonly used to detect pituitary‐dependent hyperadrenocorticism ultrasonographically in dogs. There is a substantial overlap between adrenal gland diameter of healthy dogs and of those with pituitary‐dependent hyperadrenocorticism. The aim of this study is to determine the measurements of both adrenal glands, in particular, of the height at the caudal glandular pole in a longitudinal plane, in the Labrador retriever and Yorkshire terrier, two breeds widely represented in the population suspected of hyperadrenocorticism. Seventeen Labrador retrievers and 24 Yorkshire terriers considered healthy were included in the study. Adrenal gland measurements were taken on static images and comprised in measurements of the length in a longitudinal plane (L), of the height at the cranial (CrHLG) and caudal pole (CdHLG) in a longitudinal plane and in a transverse plane (CrHTR and CdHTR, respectively), and of the width at the cranial and caudal poles in a transverse plane (CrWTR and CdWTR, respectively). This study established new upper thresholds for the left and right height at the caudal pole measured in a longitudinal plane: 7.9 mm (left) and 9.5 mm (right) for the Labrador retrievers and 5.4 mm (left) and 6.7 mm (right) for the Yorkshire terriers. All the measurements were significantly different between the two breeds. There was a significant relationship between CdHTR and CdHLG, and the age of the dogs for both breeds.     

Risk factors associated with interdog aggression and shooting phobias among purebred dogs in Denmark

The prevalence of behaviour problems is reported from a questionnaire study among members of the Danish Kennel Club (DKC). In total, 4359 dog owners were included in the analyses. With logistic regression, we analysed four behaviour problems: dominance towards the owner, interdog dominance aggression, separation anxiety and shooting phobia. Compared to Labrador Retrievers, the following breeds and breed groups had higher odds of being reported to have interdog dominance aggression: Belgian Sheepdogs, Dachshunds, Dalmatians, German Shepherds, Hovawarts, Pinschers, Rottweilers, Scent dogs and Spitz dogs. Poodles, retrieving/flushing dogs, Sheepdogs, Spitz dogs and terriers had higher odds of shooting phobia. The odds of interdog dominance aggression were higher among dogs owned by younger dog owners compared to dogs owned by older dog owners. Dogs living in the capital area of Copenhagen had increased odds of interdog dominance aggression as compared to dogs living in other parts of Denmark. Dogs belonging to owners with limited knowledge of the breed before acquiring the dog had higher odds of interdog dominance aggression. Dogs attending obedience training classes had reduced odds of shooting phobia. Dogs belonging to dog breeders had reduced odds of being reported to have the investigated behaviour problems.     

Magnetic resonance imaging of the normal canine thyroid gland.

The magnetic resonance (MR) imaging features of the normal canine thyroid gland were retrospectively compiled from images acquired in 44 dogs presented for a variety of diseases unrelated to the thyroid gland. The appearance of the thyroid gland on different sequences, including pre- and postcontrast T1-weighted, T2-weighted, two-dimensional gradient echo, three-dimensional T2*-weighted gradient echo and proton density weighted images, were described in different image planes. The characteristic shape, location, and intensity of thyroid lobes compared with surrounding structures made them easily detectable in all dogs. The most common location of the thyroid lobes was dorsolateral to the trachea with the maximal cross-sectional area of the lobes located ventral to C2/3 or C3 in more than 85% of the dogs. The majority of the lobes were ovoid on transverse images. An isthmus was seen in one large dog and parathyroid glands could not be seen. The mean maximal thyroid lobe diameter on transverse images was 8.1 mm, being twice the mean diameter of the common carotid artery. Considering the excellent conspicuity and characteristic appearance of the canine thyroid gland, MR imaging can be beneficial in the diagnosis of diffuse thyroid diseases, in differentiating thyroid vs. nonthyroid neck masses and in staging and treatment planning of thyroid tumors in this species.     

Bartonella DNA in the blood and lymph nodes of Golden Retrievers with lymphoma and in healthy controls

BACKGROUND: Although lymphoma is the most common neoplastic process reported in dogs, its precise etiology is unknown. Golden Retrievers are more likely to develop lymphoma, suggesting a breed predisposition; however, other factors, including environment, immunity, and infection, are likely contributors to oncogenesis. HYPOTHESIS: We hypothesized that the development of lymphoma in Golden Retrievers may be associated with vector-borne infections, specifically Bartonella, Anaplasma, or Ehrlichia species infections. ANIMALS: Golden Retrievers with lymphoma and healthy Golden Retrievers from across the United States were recruited for study participation. METHODS: A matched, case-control study was performed to determine the association of lymphoma and the presence of Bartonella, Anaplasma, and Ehrlichia species in serum, blood, and lymph node aspirates. RESULTS: Using PCR analyses and DNA sequencing, single and coinfections with Bartonella henselae, Bartonella elizabethae, Bartonella quintana, and/or Bartonella vinsonii (berkhoffii) were detected in the blood and lymph node aspirates of Golden Retrievers with lymphoma (5/28 dogs, 18%) and in healthy Golden Retrievers (10/56 dogs, 18%); no Anaplasma or Ehrlichia DNA was detected in any dog. When compared with dogs with lymphoma, a higher (P <.001) proportion of healthy Golden Retrievers were receiving monthly acaricide treatments (2.6 times higher). CONCLUSIONS AND CLINICAL IMPORTANCE: Bartonella DNA can be detected in blood and lymph nodes; importantly, in this report, Bartonella was detected in the same proportion of clinically healthy dogs and dogs with lymphoma. Longitudinal studies should be conducted to determine the mode of transmission of Bartonella in dogs, whether lymphatic infection is persistent, or whether these bacteria may contribute to the development of lymphoma.     

Use of dual energy x-ray absorptiometry for noninvasive body composition measurements in clinically normal dogs

OBJECTIVE: To determine quantitative values for components of body composition in clinically normal dogs of various breeds by use of dual energy x-ray absorptiometry (DEXA) and validate the precision and accuracy of DEXA technology in dogs. ANIMALS: 103 clinically normal sexually intact adult dogs. PROCEDURE: In a cross-sectional study, Beagles, Pembroke Welsh Corgis, Golden Retrievers, Great Danes, Pointers, Rottweilers, and nonpurebred dogs received total body DEXA scans. For the validation portion of the study, the results of DEXA scans of 6 dogs were compared with values obtained by chemical analyses of tissues from euthanatized dogs to determine the accuracy of this modality in dogs. RESULTS: Results (coefficient of variation) of the precision tests ranged from 0.10% for lean tissue to 5.19% for fat tissue, whereas accuracy tests revealed a difference between percentage bone mineral content and ash values. Body composition differed by sex, such as higher lean tissue and bone mineral content in males within some breeds, and among breeds. Regardless of body size or weight, the percentage of body weight that was bone mineral ranged from 3 to 4.0% [corrected]. CONCLUSIONS AND CLINICAL RELEVANCE: Results of this cross-sectional study provide valuable body composition data for clinically normal adult dogs, which may have research and clinical applications.     

ULTRASONOGRAPHIC EVALUATION OF THE PROSTATE IN HEALTHY INTACT DOGS

Sagittal and transverse ultrasonographic images of the prostate gland were obtained in 100 healthy adult intact male dogs. Prostatic length, width, and height on transverse and sagittal images as well as the presence of prostatic cysts were determined. Linear regression and correlation analysis were performed between prostatic parameters (length, width, height on sagittal and transverse images, and estimated volume) and parameters related to body size (body weight, body height, left kidney length and aortic diameter) and age of the dogs. Significant positive correlations were found between all prostatic parameters and parameters related to body size and age. Maximum predicted values for prostatic parameters for a given body weight and age were determined based on the upper limit of the 95% confidence interval of the mean predicted values. Such values should represent a useful tool for ultrasonographic evaluation of the prostate in the dog. Prostatic cysts were found in 14% of the dogs.