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Abstract

Objective—To determine associations of blood analysis variables and orbit and nasal planum surface temperatures with the onset and severity of Mycoplasma bovis pneumonia in calves.

Animals—28 healthy calves.

Procedures—Calves were challenged with M bovis (n = 24) on day 0 or not challenged (4). Blood samples were obtained for cardiac troponin I, CBC, and serum biochemical analyses on various days. Orbit and nasal planum surface temperatures were determined with infrared thermography on various days. Calves were euthanized, gross necropsies were performed, heart and lung samples were collected for histologic evaluation, and microbial cultures of lung samples were performed on day 14. Pneumonia severity was categorized as mild (< 10% lung consolidation) or moderate (≥ 10% lung consolidation). Associations between measured variables and severity of pneumonia or sample collection day were determined.

Results—Plasma cardiac troponin I concentration for the 28 calves was significantly higher on day 14 than it was on day 0 or 7 (least squares mean, 0.02, 0, and 0 ng/mL, respectively). No other variables changed significantly during the study. No substantial gross or histologic abnormalities were identified in cardiac muscle samples. Day 14 plasma fibrinogen concentration was significantly different between calves with mild pneumonia and those with moderate pneumonia (mean, 0.44 and 0.74 g/dL, respectively). Calves with moderate pneumonia had significantly lower least squares mean surface temperature of the dorsal aspect of the nasal planum (18.7°C) versus calves with mild pneumonia (22.9°C).

Conclusions and Clinical Relevance—Results indicated the evaluated variables had low value for assessment of bovine respiratory disease complex in calves.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To assess a commercially available point-of-care assay for measurement of bovine cardiac troponin I (cTnI) concentration in blood and plasma samples.

Sample—Prepared bovine plasma standard samples with known concentrations (0 to 1.0 ng/mL) of cTnI and blood and plasma samples obtained from 28 healthy 2.5-month-old Holstein calves.

Procedures—Coefficients of variation were calculated for concentrations of cTnI in prepared standards determined with the point-of-care assay, and values were compared with the known concentrations. The cTnI concentrations in blood samples obtained from calves determined with the point-of-care assay were compared with cTnI concentrations in plasma samples obtained from those animals determined with a validated immunoassay.

Results—The coefficients of variation of cTnI concentrations determined for prepared standards by use of the point-of-care assay were low (< 20%) for standards with cTnI concentrations ≥ 0.025 ng/mL. The blood cTnI concentrations determined with the point-of-care assay were not significantly different from the plasma cTnI concentrations determined with the validated immunoassay.

Conclusions and Clinical Relevance—Results of this study indicated the point-of-care assay had high precision for determination of cTnI concentrations in most evaluated prepared bovine plasma standard samples. The point-of-care assay may be useful for determination of circulating concentrations of cTnI in cattle.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate signalment, surgical treatment, postoperative complications, and future breeding success or semen production in a group of bulls with naturally occurring disease of the scrotum or testis.

Study design—Retrospective study.

Animals—21 bulls that underwent unilateral castration after evaluation for scrotal swelling.

Procedure—A computer-assisted search of medical records at 2 veterinary teaching hospitals was performed. Historical, diagnostic, surgical, and follow-up data were collected and analyzed for those bulls with scrotal swelling that underwent unilateral castration.

Results—Four of 5 pasture breeding bulls and 9 of 10 semen collection-center bulls successfully bred cows or produced viable semen within 6 months of surgery. Fourteen of 21 surgical procedures were performed after induction of general anesthesia. Sixty-six percent of procedures were performed as open castrations. Seventy-one percent of bulls developed postoperative complications, most of which were mild swellings. Unilateral castration returned 13 of 15 bulls with unilateral disease of the scrotum or testis to productive service by 6 months after surgery.

Conclusion and Clinical Relevance—Unilateral castration is an effective treatment for unilateral disease of the scrotum or testis in bulls, allowing return to reproductive function. (J Am Vet Med Assoc 2002; 220:1198–1202)

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in Journal of the American Veterinary Medical Association

Abstract

Case Description—3 alpaca crias and cadavers of an alpaca cria and a llama cria were evaluated for evidence of esophageal dysfunction.

Clinical Findings—All 5 crias were between 3 and 5 months of age when clinical signs developed, and all had a thin body condition when examined. Clinical signs included coughing, regurgitation, and grossly visible esophageal peristaltic waves. A barium esophagram was used to diagnose esophageal obstruction, megaesophagus, and a vascular ring anomaly (VRA). Fluoroscopy was used to evaluate deglutition, esophageal peristalsis, and the extent of esophageal dilation in 1 alpaca cria. A persistent right aortic arch was identified in 1 alpaca cria, and a left aortic arch with right ductus arteriosus or ligamentum arteriosum and an aberrant right subclavian artery were identified in the 4 remaining crias.

Treatment and Outcome—Surgical correction of the VRA was attempted in the 3 live alpaca crias. It was complicated by the conformation and location of each VRA and inaccurate anatomic diagnosis of the VRAs before surgery. Treatment was universally unsuccessful because of intraoperative complications and the persistence of clinical signs after surgery.

Clinical Relevance—Megaesophagus is typically an idiopathic condition in camelids. However, these findings suggested that camelids with esophageal dysfunction during the neonatal period may have a VRA. The prognosis is grave for camelids with VRA, and accurate anatomic diagnosis of the VRA via the use of advanced imaging techniques (eg, angiography, computed tomography, or magnetic resonance imaging) may improve the success of surgical intervention.

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in Journal of the American Veterinary Medical Association

Abstract

Case Description—An approximately 5-year-old sexually intact male alpaca was evaluated because of a right-sided maxillary mass that had recurred after previous surgical debulking.

Clinical Findings—Clinical, radiographic, and CT examination revealed an approximately 1.5-cm-diameter soft tissue mass associated with expansile osteolysis of the maxillary alveolar bone, beginning at the level of the right maxillary third premolar tooth extending caudally to the level of the rostral roots of the second molar tooth.

Treatment and Outcome—Right partial maxillectomy was performed, and histologic examination revealed an incompletely excised fibrosarcoma with osseous metaplasia. External beam radiation therapy to the tumor bed was initiated 1 month after surgery. Computerized planning was performed, and a total radiation dose of 48 Gy was prescribed in eleven 4.4-Gy fractions. Follow-up CT evaluations 6 and 58 weeks after radiation therapy was completed revealed no evidence of tumor recurrence. No clinical evidence of tumor recurrence was detected through 110 weeks after radiation therapy.

Clinical Relevance—The oral fibrosarcoma in the alpaca described here was successfully treated with surgical excision and adjuvant radiation therapy, resulting in excellent quality of life of the treated animal.

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate indications for and factors relating to outcome after rumenotomy or rumenostomy in cattle.

Design—Retrospective case series.

Animals—95 cattle that underwent rumenotomy or rumenostomy.

Procedures—Medical records for 95 cattle that underwent either rumenostomy or rumenotomy at 2 veterinary teaching hospitals in 1999 through 2011 were analyzed. Reasons for the procedures were noted. Long-term outcome was determined during telephone interviews with owners.

Results—42 (44%) bovids underwent rumenostomy and 53 (56%) bovids underwent rumenotomy. Among the 42 animals undergoing rumenostomy, 18 (43%) had rumen cannulas placed during elective procedures. Other indications for rumenostomy included ruminal tympany (bloat [n = 20]), esophageal obstruction (choke [1]), grain overload (1), and provision of access for administration of enteral nutrition (2). Indications for rumenotomy included traumatic reticuloperitonitis (n = 31), bloat (9), foreign body (6), choke (5), and other (2). Long-term follow-up data were available for 31 of 42 (74%) bovids that underwent rumenostomy. Of those 31 animals, 17 (55%) were still in the herd, 4 (13%) had been culled, and 10 (32%) had died or were euthanized. Long-term follow-up data were available for 38 of 53 (72%) bovids that underwent rumenotomy. Of those 38 animals, 13 (34%) were still in the herd, 14 (37%) had been culled, and 11 (29%) had died or been euthanized.

Conclusions and Clinical Relevance—Results indicated that rumenotomy and rumenostomy can be effective in treating or relieving complications secondary to forestomach disorders in cattle. Bovids undergoing rumen surgery had a favorable prognosis for survival and a fair prognosis for potential return to production.

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in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE

To describe rates of surgical complications, survival, and return to breeding soundness following herniorrhaphy for bulls with inguinal hernias.

ANIMALS

13 sexually mature bulls with acquired inguinal hernias.

PROCEDURES

Medical record databases of 3 veterinary teaching hospitals were searched to identify records of bulls that underwent herniorrhaphy for correction of an inguinal hernia from 2005 to 2017. Information extracted from the medical records included breed, age, duration and side of the hernia, surgical procedure details, postoperative complications, and information regarding subsequent fertility.

RESULTS

All 13 bulls had a left inguinal hernia and were anesthetized and underwent herniorrhaphy via an inguinal approach. The left testicle was removed during the surgical procedure in 2 bulls. Nylon or polypropylene mesh secured with size-5 polyester suture was used to facilitate inguinal ring closure in 2 bulls. The inguinal ring was closed with size-5 or size-2 polyester suture in the remaining bulls. Postoperative complications included hernia recurrence (n = 4), excessive scrotal swelling (3), and transient radial nerve paralysis (1). Follow-up information was available for 7 bulls. All 7 bulls had impregnated cows or heifers following surgery, including 1 bull that had hernia recurrence and underwent unilateral castration during the second herniorrhaphy.

CONCLUSIONS AND CLINICAL RELEVANCE

Inguinal herniorrhaphy with or without mesh was a safe and effective procedure for inguinal hernia repair in bulls and was associated with a good prognosis for subsequent fertility. However, sparing the ipsilateral testicle during the herniorrhaphy procedure might increase the risk for hernia recurrence.

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

Abstract

Objective—To determine the pharmacokinetic disposition of IV administered caffeine in healthy Lama spp camelids.

Animals—4 adult male alpacas and 4 adult female llamas.

Procedures—Caffeine (3 mg/kg) was administered as an IV bolus. Plasma caffeine concentrations were determined by use of high-performance liquid chromatography in 6 animals and by use of liquid chromatography-mass spectrometry in 2 llamas.

Results—Median elimination half-life was 11 hours (range, 9.3 to 29.8 hours) in alpacas and 16 hours (range, 5.4 to 17 hours) in llamas. The volume of distribution at steady state was 0.60 L/kg (range, 0.45 to 0.93 L/kg) in alpacas and 0.75 L/kg (range, 0.68 to 1.15 L/kg) in llamas. Total plasma clearance was 44 mL/h/kg (range, 24 to 56 mL/h/kg) in alpacas and 42 mL/h/kg (range, 30 to 109 mL/h/kg) in llamas.

Conclusions and Clinical Relevance—High-performance liquid chromatography and liquid chromatography-mass spectrometry were suitable methods for determination of plasma caffeine concentrations in alpacas and llamas. Plasma caffeine concentration-time curves were best described by a 2-compartment model. Elimination half-lives, plasma clearance, volume of distribution at steady state, and mean residence time were not significantly different between alpacas and llamas. Intravenous administration of caffeine at a dose of 3 mg/kg did not induce clinical signs of excitement.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To characterize clinical and behavioral changes in calves following inoculation with Mycoplasma bovis and evaluate relationships between those changes and pulmonary disease.

Animals—22 healthy Holstein steers.

Procedures—20 calves were inoculated intranasally with < 108 CFU or > 109 CFU of M bovis. Calves were assigned a clinical illness score (CIS) on a scale of 1 through 4 twice daily on the basis of severity of cough, labored breathing, and lethargy. For each calf, distance traveled and time spent near the waterer, feed bunk, or shelter were determined via a remote location monitoring device. Calves were euthanized and necropsied 22 days after inoculation.

Results—13 calves became clinically ill after challenge inoculation; 3 calves were euthanized within 20 days. Among all calves, consolidation was evident in 0% to 79.9% of the lungs; extent of lung consolidation did not differ between the challenge dose groups. Distance traveled and percentages of time spent in proximity to the feed bunk and shelter were associated with CIS; calves with more severe disease traveled less distance and spent less time at the feed bunk and more time in the shelter. Distance traveled by calves was negatively associated with extent of lung consolidation (< or ≥ 10% of lungs affected); this effect was modified by trial day.

Conclusions and Clinical Relevance—Following inoculation with M bovis, calf behavior patterns were associated with both CIS and severity of pulmonary disease. Use of behavior monitoring systems may aid in recognition of respiratory tract disease in calves.

Full access
in American Journal of Veterinary Research