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Ultrasonography has been used since the mid-1990s to detect violations of dairy show codes of ethics. 1 Originally used to detect gas infused into the udder to approve udder appearance, 2 ultrasonography has subsequently proven useful for detecting and quantifying a variety of injected substances, effectively eliminating these types of unethical injections from most dairy shows. 3 However, although use of prolonged (≥ 24 hours) nonmilking intervals (ie, over bagging) to artificially improve udder size and appearance has been on the list of forbidden practices in the codes of ethics for many major dairy shows for >

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in Journal of the American Veterinary Medical Association
History

A 28-year-old Quarter Horse gelding was referred to the University of Illinois Veterinary Teaching Hospital for evaluation of a suspected fracture of the left premaxilla that had occurred earlier in the day. The referring veterinarian reported an audible cracking noise when opening the horse's mouth with a McPherson full-mouth speculum during a routine oral examination. The horse had a history of chronic right-sided nasal discharge and intermittent swelling over the left rostral maxillary region.

On physical examination, there was minimal swelling over the left maxilla. Oral examination revealed a subgingival hematoma at the level of the interdental space rostral

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

Abstract

Objective—To determine the ultrasonographic appearance and detectability of edema induced by SC injection of mild silver protein suspension in the mammary gland attachments of dairy cows.

Design—Prospective study.

Animals—6 lactating cows.

Procedure—In each cow, the number of quarters that received injections was randomly assigned. A mild silver protein susoension was injected SC into cranial and caudal mammary gland attachment sites. The number of injections and volume injected were determined on the basis of the appearance of the mammary gland and the desired subjective visual effect. Seventeen sites were chosen for injection and 7 sites did not receive injections. Ultrasonographic images were obtained 1 day prior and 6 days after injections were started. Cows received injections 1, 3, and 5 days after initial sonography. The sonographer was unaware of which sites received injections.

Results—Ultrasonography revealed alternating hypoechoic and hyperechoic bands at injection sites. Certain injections caused the intimal surface of the subcutaneous abdominal vein to develop a corrugated appearance. All injection sites were correctly identified ultrasonographically (100% sensitivity, 100% specificity) with a positive and negative predictive value of 1.0.

Conclusions and Clinical Relevance—Results suggest that mild silver protein suspension injected SC to enhance the appearance of the mammary glands of dairy cows can be readily detected by ultrasonography. Detection of injection sites should be made on the basis of the distribution and ultrasonographic appearance of edema. (J Am Vet Med Assoc 2002;221:408–410)

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To investigate contrast-enhanced ultrasonography as a minimally invasive method for the subjective and quantitative assessment of pancreatic and duodenal perfusion in healthy adult dogs, with reference to perfusion in adjacent liver tissue.

Animals—8 clinically normal adult dogs.

Procedures—Contrast-enhanced ultrasonograms of the right pancreatic limb, proximal portion of the descending duodenum, and adjacent liver were acquired after IV administration of a microbubble contrast medium. Following subjective evaluation, quantitative time-intensity curves were generated from regions of interest in the pancreas, duodenum, and liver. Five contrast medium characteristics representing perfusion parameters were determined for each organ and used for statistical analysis: interval to arrival, inflow rate, peak intensity (PI), time of peak intensity (TPI), and outflow rate.

Results—Significant associations between pancreatic and duodenal values were found for interval to contrast medium arrival, PI, TPI, and outflow rate. Pancreatic and duodenal inflow rates were not correlated. Inflow and outflow rates were significantly faster and TPI significantly shorter for the pancreas and duodenum, compared with values for the liver. There was no significant difference among all 3 organs for interval to arrival and PI of contrast medium. Subjective evaluation findings corresponded to quantitative analysis results.

Conclusions and Clinical Relevance—Results suggested that contrast-enhanced ultrasonography may be a useful, minimally invasive method for evaluating pancreatic and duodenal perfusion in dogs. The data from healthy dogs reported here could aid in the assessment of pancreatic and duodenal conditions and their response to medical treatment.

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in American Journal of Veterinary Research
History

A 3-year-old 40.5-kg (89.1-lb) castrated male Labrador Retriever–mixed breed dog was admitted to the University of Illinois Veterinary Teaching Hospital because of a 10-day history of stridor and inspiratory obstructive dyspnea. The clinical signs were intermittent and paroxysmal (5 minutes’ duration/episode) and sometimes related to exercise.

Clinical and Gross Findings

At admission, findings of a physical examination, CBC, serum biochemical profile, urinalysis, and coagulation profile were unremarkable. The dog was breathing normally in the examination room. Tracheal radiography identified an intratracheal circular 1.7-cm-diameter soft tissue mass at the level of the fourth and fifth cervical vertebrae. The mass occupied

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

Abstract

Objective—To evaluate the effect of oral administration of melatonin on clinical signs, tumor size, and serum steroid hormone concentrations in ferrets with adrenocortical disease.

Design—Noncontrolled clinical trial.

Animals—10 adult ferrets with clinical signs of adrenocortical disease (confirmed via serum steroid hormone concentration assessments).

Procedures—Melatonin (0.5 mg) was administered orally to ferrets once daily for 1 year. At 4-month intervals, a complete physical examination; abdominal ultrasonographic examination (including adrenal gland measurement); CBC; serum biochemical analyses; and assessment of serum estradiol, androstenedione, and 17α-hydroxyprogesterone concentrations were performed. Serum prolactin and dehydroepiandrosterone sulfate concentrations were evaluated at the first, second, and last examinations, and serum cortisol concentration was evaluated at the first and last examinations.

Results—Daily oral administration of melatonin greatly affected clinical signs of adrenocortical disease in ferrets; changes included hair regrowth, decreased pruritus, increased activity level and appetite, and decreased vulva or prostate size. Mean width of the abnormally large adrenal glands was significantly increased after the 12-month treatment period. Recurrence of clinical signs was detected in 6 ferrets at the 8-month evaluation. Compared with pretreatment values, serum 17α-hydroxyprogesterone and prolactin concentrations were significantly increased and decreased after 12 months, respectively.

Conclusions and Clinical Relevance—Results suggest that melatonin is a useful, easily administered, palliative treatment to decrease clinical signs associated with adrenocortical disease in ferrets, and positive effects of daily treatment were evident for at least an 8-month period. Oral administration of melatonin did not decrease adrenal gland tumor growth in treated ferrets.

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate perfusion of abdominal organs in healthy cats by use of contrastenhanced ultrasonography.

Animals—10 young healthy anesthetized cats.

Procedures—Contrast-enhanced ultrasonography of the liver, left kidney, pancreas, small intestine, and mesenteric lymph nodes was performed on anesthetized cats.

Results—Typical perfusion patterns were found for each of the studied organs. Differences in perfusion among organs were associated with specific physiologic features. The liver was enhanced gradually and had a more heterogeneous perfusion pattern because of its dual blood supply and close proximity to the diaphragm, compared with other organs. An obvious and significant difference in perfusion was detected between the renal cortex and medulla. No significant differences in perfusion were detected among the pancreas, small intestine, and mesenteric lymph nodes.

Conclusions and Clinical Relevance—Results indicated that contrast-enhanced ultrasonography can be used in cats to estimate organ perfusion as in other species. Observed differences in perfusion variables can be mostly explained by physiologic differences in vascularity. (Am J Vet Res 2010;71:1305–1311)

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in American Journal of Veterinary Research