Search Results

Abstract

Objective—To characterize amphotericin B–induced lameness in cattle and to ascertain the analgesic effects of flunixin meglumine by use of multimodal assessment.

Animals—10 healthy Holstein steers free from musculoskeletal disease.

Procedures—Steers were randomly allocated to a treatment or negative control group. Amphotericin B was injected into the distal interphalangeal joint of the lateral claw of the left hind limb of all steers. Treatment steers received flunixin meglumine at the time of synovitis-arthritis induction and at 12 hours after induction. Control steers received no medication. Multimodal analysis included vital parameters, visual lameness score, behavioral monitoring with accelerometers, pressure mat analysis, and plasma cortisol determination before and after induction. Data were analyzed by use of linear mixed models with treatment and time designated as fixed effects, accounting for repeated measures on individual calves.

Results—Amphotericin B injection induced moderate, transient lameness. Control steers were more than twice as likely to be lame as treatment steers (mean ± SD lameness score, 92.2 ± 8.1 % vs 40.7 ± 2.5%). Treatment steers placed significantly greater force and contact area on the affected foot and greater force, impulse, and contact area on the paired claw, compared with control steers. Furthermore, treatment steers spent considerably less time in recumbency than controls.

Conclusions and Clinical Relevance—Amphotericin B successfully induced synovitis-arthritis in dairy steers that was transient in nature. Flunixin meglumine was efficacious in providing analgesia for these steers.

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.

Abstract

Objective—To evaluate the effect of ambient temperature on viral replication and serum antibody titers following administration of an intranasal modified-live infectious bovine rhinotracheitis (IBR)-parainfluenza-3 (PI3) virus vaccine to beef calves housed in high– (> 32°C) and moderate– (21°C) ambient temperature environments.

Animals—28 calves (mean weight, 206.8 kg).

Procedures—Calves were randomly allocated to 4 treatment groups (housed outdoors during high ambient temperature with [HAT; n = 10] or without [HAC; 4] vaccination or housed indoors in a moderate ambient temperature with [MAT; 10] or without [MAC; 4] vaccination). Rectal and nasal mucosal temperatures were recorded every 2 hours from 8 AM to 8 PM on days 0 (vaccination) and 1. Nasal swab specimens were obtained on days 0 through 7 for virus isolation. Serum samples were collected on days 0, 7, 14, and 28 for determination of antibody titers.

Results—Mean rectal temperature did not differ among the treatment groups. Mean nasal temperature for the HAT group was significantly higher than that for the MAT group at 6, 24, 30, 32, and 38 hours after vaccination. Viable IBR virus was isolated from all vaccinated calves on days 1 through 6. Two weeks after vaccination, vaccinated calves had anti-IBR antibody titers that were significantly greater than those for unvaccinated calves. Mean anti-IBR antibody titers did not differ significantly between the HAT and MAT groups.

Conclusions and Clinical Relevance—Results indicated that, following vaccination with an intranasal modified-live IBR-PI3 virus vaccine, IBR viral replication and serum antibody titers did not differ significantly between calves housed in high– and moderate–ambient temperature environments.

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.

Abstract

Objective—To determine effects of ambient temperature, relative humidity, wind speed, relative barometric pressure, and temperature-humidity index (THI) on nasal submucosal and rectal temperatures in cattle during extreme summer conditions.

Animals—20 black crossbred beef heifers (mean body weight, 217.8 kg).

Procedures—Nasal submucosal and rectal temperatures were monitored every 2 hours for 24 hours on 3 nonconsecutive days when ambient temperature was forecasted to exceed 32.2°C. Ambient temperature, relative humidity, wind speed, and relative barometric pressure were continuously monitored at a remote weather station located at the research facility. The THI was calculated and used in the livestock weather safety index (LWSI). Relationships between nasal submucosal or rectal temperature and weather variables were evaluated.

Results—Nasal submucosal and rectal temperatures were related to all weather variables monitored. A positive relationship was determined for ambient temperature and THI with both nasal submucosal and rectal temperatures. A negative relationship was evident for nasal submucosal and rectal temperature with relative humidity, wind speed, and relative barometric pressure. Nasal submucosal and rectal temperatures increased with increasing severity of LWSI category.

Conclusions and Clinical Relevance—Effects of environmental conditions on thermoregulation in calves exposed to extreme heat were detected. The positive relationship between nasal submucosal temperature and ambient temperature and THI raised concerns about the efficacy of intranasal administration of temperature-sensitive modified-live virus vaccines during periods of extreme heat. Environmental conditions must be considered when rectal temperature is used as a diagnostic tool for identifying morbid cattle.

Abstract

Objective—To describe clinical findings, treatments, and outcome in camelids treated for osseous sequestration.

Design—Retrospective case series.

Animals—27 alpacas and 9 llamas with osseous sequestration.

Procedures—Medical records of 2 veterinary teaching hospitals were reviewed to identify camelids evaluated because of osseous sequestration between January 1, 1999, and December 31, 2010. Data on history, signalment, physical examination and medical imaging findings, treatment, and complications were collected.

Results—Records of 36 camelids were included, of which there were 22 sexually intact males, 11 females, and 2 castrated males with a median age of 7. 5 months, 3.9 months, and 8.5 years, respectively (age and sex were not available for 1 camelid). The most common clinical signs were lameness, swelling over the affected bone, and associated draining sinus. Sequestra were associated with trauma in 7 (19%) camelids. Camelids with sequestra not associated with trauma (n = 29 [81%]) were significantly younger than those with sequestra attributed to trauma. Thirty-four camelids underwent sequestrectomy, and all survived to hospital discharge (median duration of hospitalization, 6.5 days). Recurrence of a sequestrum occurred twice in 1 (3%) camelid. Long-term follow-up (≥ 12 months) information was available on 24 camelids, of which 20 (83%) recovered without long-term complications.

Conclusions and Clinical Relevance—Unlike in other livestock, trauma was not a primary cause of osseous sequestration in camelids. Sequestra should be considered in the differential diagnostic process in camelids with lameness, a draining sinus, or a firm swelling over a bony prominence. Sequestrectomy is a successful treatment option.

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.

Abstract

Objective—To describe the clinical findings, treatments, and outcome in alpacas treated for scapulohumeral joint luxation (SHJL).

Design—Retrospective case series.

Animals—10 alpacas.

Procedures—Medical records of alpacas with SHJL that were treated at 2 referral hospitals were reviewed. History, signalment, physical examination results, radiographic findings, treatments, complications, and outcome were evaluated.

Results—Records for 8 male and 2 female alpacas with 16 instances of SHJL were reviewed. Three male alpacas each had 2 recurrences of SHJL in the treated limb. The proportion of male alpacas treated for SHJL was significantly greater than the proportion of female alpacas treated for SHJL. Closed reduction was used in 2 female and 3 male alpacas; SHJL reccurred in the 3 males. Stabilization by use of a lateral extracapsular tension band suture technique was performed successfully in 4 male alpacas; in another male alpaca, reluxation caused by self-inflicted trauma occurred postoperatively. In 2 male alpacas, arthrodesis was performed but residual lameness remained 1 year after surgery.

Conclusions and Clinical Relevance—SHJL should be considered as a differential diagnosis in alpacas with thoracic limb lameness. Luxation may occur more frequently in males. A closed reduction technique may be used successfully to treat acute luxations. Extracapsular stabilization by use of the lateral extracapsular tension band suture technique was successful for treatment of recurrent SHJL and SHJL that could not be reduced via closed reduction.

Abstract

Objective—To evaluate with CT the efficacy of various combinations of firearms and ammunitions to penetrate and disrupt the brain tissue of cadaveric heads of feedlot steers.

Sample—42 fresh cadaveric heads of 12- to 18-month-old Bos taurus steers.

Procedures—For each of 7 combinations of firearms and ammunitions (.22-caliber rifle firing a long rifle 30-grain plated lead solid- or hollow-point round, .223-caliber carbine firing a 50-grain ballistic-tip round, 9-mm pistol firing a 124-grain total metal jacket round, .45-caliber automatic Colt pistol [ACP] firing a 230-grain full metal jacket round, and 12-gauge shotgun firing a 2.75-inch 1.25-ounce No. 4 birdshot shell or a 1-ounce rifled slug), 6 cadaveric heads were shot at an identical distance (3 m), angle, and anatomic location. Heads were scanned with third-generation CT, and images were evaluated to determine extent of penetration, projectile fragmentation, cranial fracture, and likelihood of instantaneous death (≥ 30% destruction of brain tissue or a brainstem lesion).

Results—41 of 42 skulls were penetrated by the projectile. Instantaneous death was considered a likely consequence for 83% (25/30) of heads shot with a rifle-fired .22-caliber solid-point round, pistol-fired .45-caliber ACP round, carbine-fired .223-caliber round, and shotgun-fired birdshot and slug. Of the 18 heads shot with pistol-fired 9-mm and .45-caliber ACP rounds and rifle-fired .22-caliber hollow-point rounds, only 6 had brainstem lesions.

Conclusions and Clinical Relevance—Results suggested that gunshots delivered by all firearm-ammunition combinations except rifle-fired .22-caliber hollow-point rounds and pistol-fired 9-mm rounds were viable options for euthanasia of feedlot cattle.