Search PubMed⌕ Search

Biomedical subjects

H M Hayes

Publications and source records attributed to H M Hayes.

At least 37 records · Page 2Linked to original sources

Mortality patterns among US veterinarians, 1947-1977: an expanded study.

Causes of death among 5016 white male veterinarians identified from obituary listings in the Journal of the American Veterinary Medical Association were compared to a distribution based on the general US population. Proportions of deaths were significantly elevated for cancers of the lymphatic and haematopoietic system, colon, brain, and skin. Fewer deaths were observed than expected for cancers of the stomach and lung. Although socio-economic and methodological factors may be involved, the patterns suggest that sunlight exposure is responsible for the excess of skin cancer among veterinarians whose practices are not exclusively limited to small animals, and ionizing radiation exposure contributes to the excess of leukaemia among veterinarians practising during years when diagnostic radiology became widely used. Mortality was also high for motor vehicle accidents and suicides, but low for diseases of the respiratory system.

Adult↗

Carcinoma of the nasal cavity and paranasal sinuses in dogs: descriptive epidemiology.

A retrospective study of medical records from 15 veterinary university teaching hospitals and clinics yielded 504 dogs with microscopically confirmed primary carcinoma of the nasal cavity or paranasal sinuses. When compared to the hospital population at risk, males showed a 1.3 fold excess risk (p less than or equal to 0.05), adjusted for age and gonadal status, compared to females. The male excess persisted from 1 through 14 years of age. Dolichocephalic dogs (specifically the Collie and Sheltie) had a higher risk than other dogs and brachycephalic dogs had a lower risk, but these variations may not be a simple function of skull type. Seven breeds of dogs were identified with a significantly high risk and two with low risk. Among breeds with mesaticephalic type skulls, risk was not associated with adult body weight, used as a measure of body size and tidal air requirement. Mongrel dogs, often spared from other types of cancer, displayed the same risk as all breeds combined, suggesting the influence of environmental factors.

Animals↗

Epidemiological features of feline mammary carcinoma.

An epidemiological survey involving 132 cats with mammary neoplasia, seen at 15 North American veterinary medical teaching hospitals, was conducted. The ratio of malignant to benign tumours was 9:1. There were 113 cases of carcinomas of all types (including two males), with adenocarcinoma being the predominant cell-type. Relative risk analysis indicated that the Siamese breed had twice the risk (P less than 0.01) of developing mammary carcinoma compared to all breeds combined. The age at diagnosis in Siamese females tended to be younger than in other breeds. Comparison of clinical and pathological features of breast cancer suggests that the cat is an appropriate surrogate for the experimental study of human breast cancer. The apparent lack of oestrogen dependency in feline breast cancer also suggests that the cat may be especially suited for evaluating therapeutic regimens for breast cancers that do not respond to hormonal manipulation.

Animals↗

Bladder cancer in pet dogs: a sentinel for environmental cancer?

Proportional morbidity ratios (PMRs) were calculated for cancers, by site or type, in 8760 pet dogs seen at 13 veterinary medical teaching hospitals in the United States and Canada. A significant positive correlation was seen between the PMRs for canine bladder cancer and the overall level of industrial activity in the host county of the hospital. An analysis of mortality from bladder cancer among white men and women in the same US counties showed similar correlations with industrial activity. Canine bladder cancer could be a sentinel condition whose investigation in locales might lead to early identification of carcinogenic hazards in the general environment.

Adolescent↗

Epidemiologic features of canine hypothyroidism.

This study investigates the epidemiologic features of 3,206 dogs diagnosed with hypothyroidism (including myxedema) from 1.1 million dogs seen at 15 veterinary teaching hospitals between March, 1964 and June, 1978. Nine breeds found to be at high-risk for hypothyroidism were: golden retrievers, Doberman pinschers, dachshunds, Shetland sheepdogs, Irish setters, Pomeranians, miniature schnauzers, cocker spaniels, and Airedales. Two breed with a significant deficit of risk were German shepherds and mixed breed (mongrel) dogs. Age risk was greatest among younger dogs of high-risk breeds, further suggesting a genetic component to the etiology of this disease. In contrast, low-risk dogs had increasing relative risk through nine years of age. Spayed female dogs displayed a significantly higher risk when compared to intact females. Though not statistically significant, male castrated dogs had 30% more hypothyroidism compared to their intact counterparts. Among the case series were 91 endocrine and hormone-related neoplasms and 198 other endocrine-related disorders. Further studies linking canine hypothyroidism to other conditions, particularly cancer, could provide valuable insight into human disease experience.

Age Factors↗

Cancer and other causes of death among U.S. veterinarians, 1966-1977.

Causes of death among 1,551 white male veterinarians identified from obituary listings in the Journal of the American Veterinary Medical Association were compared to an expected distribution based on the general US population. The proportion of deaths was significantly high for particular neoplasms, especially leukemia and Hodgkin's disease, and cancers of the brain and skin. Although socioeconomic and methodologic factors may be involved, the excesses were primarily among veterinarians in clinical practice, raising the possibility that specific occupational exposures may be carcinogenic. Mortality was also relatively high for motor vehicle accidents, suicides and asthma, but low for lung cancer and other diseases of the respiratory system.

Age Factors↗

Risk factors associated with canine heartworm infection.

Risk factors associated with canine heartworm infection were determined by screening medical records from the Veterinary Medical Data Program of June 1964--May 1976. Data represented were from 14 colleges and schools of veterinary medicine in the United States and Canada. A total of 3,655 dogs were infected. Intact male dogs 4 to 7 years old and of the larger hound breeds had the highest relative risk, whereas dogs of smaller breeds, those less than 2 years old, spayed females, and castrated males were at least risk.

Age Factors↗

Castration for treatment of perianal gland neoplasms in the dog.

Neoplasms of the perianal gland are common in the dog, particularly the male. Adenomas of the gland develop about 4.5 times more often than do carcinomas of the gland. The adenoma is hormone dependent; thus, castration without excision of the tumor has been successful in promoting regression without recurrence. Microscopic examination of the testes from dogs with perianal gland neoplasms has revealed 1 in 10 with tubular atrophy and 1 in 3 with testicular neoplasia. Interstitial cell tumors have been seen more often than other cell types of testis tumors.

Adenoma↗

Epizootiologic features of canine hydrocephalus.

In a retrospective study of hydrocephalus (of congenital origin) diagnosed in 564 dogs, 11 breeds (including 8 "toy" breeds) were identified as being a significantly high risk. An inverse relationship between risk and body size was detected. The smaller the dam at maturity, either in height at the shoulder or body weight, the greater the risk of hydrocephalus in the offspring.

Animals↗

Patent ductus arteriosus in the dog: a retrospective study of radiographic, epidemiologic, and clinical findings.

Twenty-seven cases of patent ductus arteriosus (PDA) in the dog, which were confirmed by cardiac catheterization, surgical exploration, or at necropsy, were reviewed. A machinery murmur, electrocardiographic evidence of left ventricular enlargement, and radiographic evidence of cardiomegaly with an aortic and a pulmonary artery dilatation were consistent features. Surgical repair was successful in 65% of the dogs. The postoperative radiographic and electrocardiographic changes are described. A concomitant congenital defect was present in 2 dogs. The epidemiologic features of 532 dogs identified as having PDA and submitted to the National Cancer Institute's Veterinary Medical Data Program were reviewed. Miniature and Toy Poodles, Pomeranians, and Shetland Sheepdogs were identified as being at high risk for PDA. An excess of females over males was noticed.

Animals↗

Epidemiology and toxicology of arsenic poisoning in domestic animals.

Arsenic poisoning is one of the more important causes of heavy metal poisoning in domestic animals. Two species--dogs and cattle--are intoxicated more frequently than other animals; yet sporadic instances of poisoning have been observed in cats, horses, and pigs. Cases observed by veterinary clinicians are either peracute, acute, or chronic intoxications. Frequently the initial and only indication that a severe problem exists with peracute poisoning in a cattle herd is dead animals. Chronic intoxications are also observed in cattle. Acute intoxication is the most common form of arsenic poisoning observed and documented in the dog. Also intoxicated dogs were younger, i.e., 2-6 months of age. Arsenic is a severe alimentary tract irritant in domestic animals, and treatment in most instances consists mainly of symptomatic and supportive treatment. The source of intoxication, when it can be determined, is usually dips, sprays, powders, or vegetation contaminated by pesticides containing arsenic.

Animals↗

Hormone-dependent neoplasms of the canine perianal gland.

The epidemiological features of 472 dogs with microscopically confirmed neoplasms of the perianal gland are described. These general characteristics suggest etiological factors similar to those responsible for hormone-related neoplasms occurring in human beings. Perianal gland tumors appear to be androgen dependent. Male dogs show a 5.6-fold-increased risk compared with females; endogenous estrogens offer protection and the use of estrogenic hormones is conventional therapy for the benign lesion. Both sexes of the cocker spaniel breed show excessively high risk, suggesting that this dog family may be a model for genetic studies that could be relevant to familial aggregations of hormone-related tumors in men and women. Adrenocortical hormones may play a role in the development of the tumor in female dogs. Research into alterations of the biochemical pathways of steroidogenesis in affected female dogs may provide clues to similar conditions in humans.

Anal Gland Neoplasms↗

Epidemiological features of canine renal neoplasms.

A retrospective study of medical records from 13 veterinary university hospitals and clinics yielded 73 cases of confirmed primary neoplasms of the kidney and renal pelvis. Analysis of the 34 cases of renal carcinoma revealed no evidence of familial (breed) predisposition, but an excess risk was identified in males, especially during middle life. The morphological and epidemiological features of canine renal carcinoma are similar to those of renal carcinoma in humans. The dog may be a suitable model for further research into the causes of this cancer.

Animals↗

Canine testicular tumors: epidemiologic features of 410 dogs.

Histologically confirmed testicular tumors were diagnosed in 410 dogs from 12 North American veterinary university hospitals and clinics. Three tumor-cell types, Sertoli cell tumor, interstitial cell tumor and seminoma, were about equally represented. Several breeds were identified with high risk for different testicular tumor-cell types. Cytogenetic and immunogenetic studies of these dog families could offer leads applicable to familial testicular cancer in man. The multiplicity of breeds within the series suggests that, as in man, other factors, in addition to hereditary, play a role in etiology. Cryptorchid dogs appear to have a 13.6 times higher risk of testicular tumor than normal dogs. Additionally, male dogs with an inguinal hernia have an increased risk (4.7) of testis tumors. There were no detectable excesses of other urogenital anomalies or urogenital tumors among the series. The Shetland Sheepdog is suggested as an appropriate model for research into the mechanisms responsible for testicular maldescent and tumorigenesis.

Age Factors↗

Canine bladder cancer: epidemiologic features.

A retrospective study of medical records from 13 veterinary university hospital clinics yielded 114 dogs with microscopically confirmed primary malignancy of the bladder. When matched to controls, there was no increased frequency to suggest an association of urogenital tumors or anomalies with neoplasms of the bladder. The majority of tumors seen in this study were transitional cell carcinomas. Four breeds were identified with excessive risk for bladder cancer and may serve as models for further research into genetic determinants, such as abnormal tryptophan metabolism. The epidemiologic features of canine bladder cancer were compared with the disease in man. An excess among female dogs may be the result of less frequent urination as compared to male dogs. Assuming an etiology from urine-borne carcinogens applies to spontaneously occurring bladder cancer in dogs, then monitoring the frequency of occurrence of canine bladder cancer may provide an early warning of emerging environmental hazards to man.

Animals↗

Occurrence of nervous-tissue tumors in cattle, horses, cats and dogs.

From 11 North American veterinary university hospitals and clinics, 248 animals were a confirmed diagnosis of nervous-tissue tumor were identified; 7 tumors were found in cattle, 28 in horses, 14 in cats, 199 in dogs, and none in other species. Tumors were divided for analysis into three categories-glial, meningeal, and peripheral nerve. In cattle and horses, all tumors involved peripheral nerves, the risk of which, in horses, reached a plateau at 4-6 years of age and remained constant thereafter. In cats, the tumors were equally distributed among the three tumor categories whereas, in dogs, twice as many glial tumors as meningeal and peripheral nerve tumors were found. The risk for glial tumors in dogs reached a peak at 10-14 years of age, for meningeal at 7-9 years, and for peripheral nerve at 2-3 and 7-9 years. Three canine breeds-English bulldog, boxer, and Boston terrier-had an excessive rish of glial tumors. Except for an excess of skin tumors in dogs with peripheral nerve tumors, there was no unusual occurrence with second primary neoplasms for any species. There was no detectable predisposition by sex for any of the categories of nervous-tissue tumors among any of the four species. The role of genetic abnormalities associated with nervous-tissue tumors and other etiologic factors (e.g., chronic hypoxia) may be clarified by further studies involving canine breeds of "bulldog" ancestry.

Age Factors↗

Cryptorchism and related defects in dogs: epidemiologic comparisons with man.

In a study of 1266 dogs with cryptorchism from a large clinic/hospital series 8 breeds were found to be at excess risk of the defect and 3 breeds at significantly low risk. Review of the medical histories revealed that hip dysplasia, patellar dislocation, defects of the penis and prepuce, and umbilical hernia were excessively associated with cryptorchism. Testicular tumors were diagnosed 10.9 times more commonly among cryptorchid dogs. The epidemiologic features of canine cryptorchism were compared with those in man. Cryptorchid dogs could be used as models for etiologic research.

Animals↗