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To determine the effects of heat stress and drinking water treatments on physical characteristics of skeletal tissue, tibias of cockerels ranging in age from 4 to 11 weeks were tested for breaking strength. Birds were subjected to either a thermoneutral environment (21 ± 2 C) or a hot environment (37 ± 2 C) and supplied with either tap or carbonated drinking water. Breaking strength of tibias was reduced in the hot environment; however, consumption of carbonated drinking water in the hot environment resulted in bone strength comparable with that associated with thermoneutral environment (both types of water). Also, bones from birds of the carbonated water- 37 C treatment group had less phase breaks and tended to separate with a single break. Results indicate that hot environment and carbonated drinking water not only affect the previously reported morphologic and chemical characteristics of developing bone, but also their physical attributes.

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in American Journal of Veterinary Research


The performance of the serum complement fixation (cf) test was compared with that of a serum agar gel immunodiffusion (agid) test on 74 subclinically infected and 154 uninfected cattle in 6 commercial midwestern dairy herds with Mycobacterium paratuberculosis infection and on 30 cattle in a herd that was free of infection. Infection status of cattle within herds was established by performance of a series of 3 or more fecal cultures and of ileocecal lymph node cultures of culled cattle.

In cattle with subclinical infection detected by culturing, the sensitivity estimates of the cf and agid tests were 10.8% (3.6% se) and 18.9% (4.5% se), respectively, In the cattle classified as disease free, the specificity estimates of the cf and agid tests were 97.4% (1.3% se) and 99.4% (0.6% se), respectively. Neither set of estimates was significantly different.

Negative test results obtained with the use of either test in apparently normal cattle from suspect herds should be interpreted with caution because both tests suffer from how sensitivities in subclinically infected animals. However, the agid test may be more useful in regulatory situations in which the cf test is currently used because the agid test is easier to perform and to interpret.

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in American Journal of Veterinary Research


To evaluate use of urine cortisol-to-creatinine ratio (UC:C) as a means of monitoring response to long-term mitotane treatment in dogs with pituitary-dependent hyperadrenocorticism.


Prospective uncontrolled study.


101 dogs with pituitary-dependent hyperadrenocorticism.


Urine samples were obtained from dogs on the morning an ACTH stimulation test was performed, and owners were asked their opinion on the health of their dog to monitor response to mitotane treatment. Urine was assayed for cortisol and creatinine concentrations, and UC:C was calculated. The UC:C was compared with post-ACTH plasma cortisol concentration.


Post-ACTH plasma cortisol concentration was used to categorize each dog's response to mitotane treatment. The UC:C did not correlate satisfactorily with results of ACTH stimulation testing. Twenty-seven of 85 (32%) dogs would have been incorrectly considered as having received appropriate doses using UC:C. In addition, 16 dogs that received overdoses could not be distinguished from 29 dogs that received appropriate doses.

Clinical Implications

UC:C does not provide a consistent, correct assessment of mitotane-induced adrenocortical destruction. The ACTH stimulation test, although more time-consuming and expensive, is recommended for monitoring response to mitotane treatment. (J Am Vet Med Assoc 1997;211:1002–1004)

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in Journal of the American Veterinary Medical Association


Objective—To determine toxic effects of streptozocin given in combination with a diuresis protocol in dogs and establish whether streptozocin is efficacious in treatment of pancreatic islet cell tumors in dogs.

Design—Retrospective study.

Animals—17 dogs.

Procedure—Medical records were reviewed to obtain information regarding signalment, tumor stage and staging tests performed, number of streptozocin treatments, adverse effects, results of biochemical and hematologic monitoring during streptozocin treatment, tumor dimensions, duration of normoglycemia, and date of death, when applicable. Dogs were compared with a historical control group of 15 dogs treated surgically and medically.

Results—58 treatments were administered to the 17 dogs. Only 1 dog developed azotemia. Serum alanine aminotransferase activity increased in some dogs but decreased when treatment was discontinued. Hematologic toxicoses were rare. Vomiting during administration was uncommon but occasionally severe. Two dogs developed diabetes mellitus after receiving 5 doses. Median duration of normoglycemia for 14 dogs with stage-II or -III insulinoma treated with streptozocin was 163 days (95% confidence interval, 16 to 309 days), which was not significantly different from that for the control dogs (90 days; 95% confidence interval, 0 to 426 days). Two dogs had rapid resolution of paraneoplastic peripheral neuropathy, and 2 others had measurable reductions in tumor size.

Conclusions and Clinical Relevance—Results suggest that streptozocin can be administered safely to dogs at a dosage of 500 mg/m2, IV, every 3 weeks when combined with a protocol for induction of diuresis and may be efficacious in the treatment of dogs with metastatic pancreatic islet cell tumors. (J Am Vet Med Assoc 2002;221:811–818)

Full access
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association



To assess signalment, clinical findings, and treatments for New World camelids (NWCs) hospitalized for evaluation and treatment of neonatal disorders and investigate associations between these factors and death during and after hospitalization.


267 NWCs ≤ 30 days of age.


Medical records of a veterinary teaching hospital were retrospectively reviewed to identify NWCs admitted for evaluation and treatment of neonatal disorders between 2000 and 2010. Signalment, physical examination data, diagnostic findings, treatments, and outcomes were recorded. Factors were examined for association with death during hospitalization and the overall hazard of death by use of multivariable logistic regression and Cox proportional hazards analysis, respectively.


The sample comprised alpacas (n = 255) and llamas (12). Median age at admission was 3 days, and median hospitalization time was 2 days; 208 of the 267 (77.9%) neonatal NWCs survived to hospital discharge. Factors associated with increased odds of death during hospitalization included prematurity or dysmaturity, hypothermia, sepsis, toxic changes in neutrophils, and undergoing surgery. The odds of death during hospitalization also increased as anion gap increased. After discharge, 151 of 176 (85.8%) animals had follow-up information available (median follow-up time, 2,932 days); 126 (83%) were alive and 25 (17%) had died. Prematurity or dysmaturity, congenital defects, sepsis, oxygen administration, and undergoing surgery as a neonate were associated with an increased hazard of death; the hazard of death also increased as serum chloride concentration at the time of hospitalization increased.


Results suggested the prognosis for survival during and after hospitalization is good for most NWCs hospitalized because of neonatal disorders.

Full access
in Journal of the American Veterinary Medical Association


Objective—To evaluate a portable real-time reverse transcriptase-polymerase chain reaction (RT-PCR) assay designed to detect all 7 viral serotypes of footand- mouth disease virus (FMDV).

Design—Laboratory and animal studies.

Study Population—Viruses grown in tissue culture and animals experimentally infected with FMDV.

Procedure—1 steer, pig, and sheep were infected with serotype O FMDV. Twenty-four hours later, animals were placed in separate rooms that contained 4 FMDV-free, healthy animals of the same species. Oral and nasal swab specimens, oropharyngeal specimens obtained with a probang, and blood samples were obtained at frequent intervals, and animals were observed for fever and clinical signs of foot-and-mouth disease (FMD). Samples from animals and tissue cultures were assayed for infectious virus and viral RNA.

Results—The assay detected viral RNA representing all 7 FMDV serotypes grown in tissue culture but did not amplify a panel of selected viruses that included those that cause vesicular diseases similar to FMD; thus, the assay had a specificity of 100%, depending on the panel selected. The assay also met or exceeded sensitivity of viral culture on samples from experimentally infected animals. In many instances, the assay detected viral RNA in the mouth and nose 24 to 96 hours before the onset of clinical disease.

Conclusions and Clinical Relevance—The assay reagents are produced in a vitrified form, which permits storage and transportation at ambient temperatures. The test can be performed in 2 hours or less on a portable instrument, thus providing a rapid, portable, sensitive, and specific method for detection of FMDV. (J Am Vet Med Assoc 2002;220:1636–1642)

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in Journal of the American Veterinary Medical Association