Matt D. Miesner

Effect of Mannheimia haemolytica pneumonia on behavior and physiologic responses of calves during high ambient environmental temperatures1

The objective of this study was to determine the effect of pneumonia during conditions of high (maximum ≥ 32°C) ambient temperatures on physiological and behavioral responses of calves. Eighteen black beef heifers averaging 240 kg were blocked by BW and randomly assigned to 1 of 2 treatment groups: 1) pneumonia induced by bronchoselective endoscopic inoculation with Mannheimia haemolytica (MH; n = 10) and 2) noninoculated controls (CN; n = 8). Nasal passage and rectal temperatures were measured every 2 h for 24 h after challenge and then twice daily for 9 d. Accelerometers, pedometers, and positioning devices monitored cattle behavior within the pen for 9 d after challenge. Blood samples were collected on trial d 0, 0.5, 1, 2, 3, 7, and 9 and were analyzed to determine the concentration of substance P, cortisol, haptoglobin, and metalloproteinase. All calves in the MH group were euthanized and necropsied on trial d 9. All MH calves became clinically ill postchallenge. A treatment × time interaction (P < 0.05) was evident for nasal and rectal temperatures, behavior, weight, and blood analysis. Rectal temperatures in MH were higher (P < 0.01) than CN during the period from 6 to 24 h after challenge. Conversely, nasal passage temperatures were less in MH calves compared with CN at 12 to 22 h after challenge. Calves in MH spent less time at the grain bunk, less time at the hay feeder, and more time lying down during the early pneumonia period compared with CN calves. Also, MH calves had significantly greater concentrations of blood biomarkers of pain (substance P) on d 0.5 (P < 0.01); stress (cortisol) on d 0.5 and 1 (P < 0.01); haptoglobin on d 0.5, 1, 2, 3, 7 (P < 0.01); and metalloproteinase on d 1, 2, and 3 (P < 0.01) compared with CN calves. At necropsy, all MH calves had right cranioventral bronchopneumonia (median lung lesions = 6.8%). Mannheimia haemolytica pneumonia caused significantly more changes in behavior and increased biomarkers during high (maximum ≥32°C) ambient temperatures compared with control calves. The results of this study may guide research in the development of objective assessment tools for management of cattle affected with bovine respiratory disease during extreme summer conditions.

Surgery of Obstructive Urolithiasis in Ruminants

Most cases of obstructive urolithiasis will require surgical intervention at some point during the treatment process. Fluid, anti-inflammatory, antibiotic, and acidifying therapies should be used in support of surgical intervention. Surgical technique may be chosen based on the characteristics of the individual case, including site of obstruction, location of the rupture, and value of the animal. Prevention remains the mainstay of urolithiasis management. Identification of a case of obstructive urolithiasis should trigger action for the affected individual and the entire herd or flock of origin.

Effect of flunixin meglumine on the amelioration of lameness in dairy steers with amphotericin B-induced transient synovitis-arthritis.

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.

Management of Uterine and Vaginal Prolapse in the Bovine

Uterine prolapse in cows is a historic topic that is well discussed in scientific veterinary literature and texts, argued at legendary proportion between practitioners, and even referenced in western poetry. The condition occurs sporadically and is recognized easily, but sometimes it is not so easily repaired. This article discusses the replacement, repair, and removal of the uterus and helpful techniques and potential complications. Because the veterinarian occasionally encounters situations where manual eversion (iatrogenic prolapse) of the uterus is helpful, particularly for efficiently repairing the traumatized uterus in the field, a technique for iatrogenic prolapse is discussed.

Effect of transportation during periods of high ambient temperature on physiologic and behavioral indices of beef heifers

OBJECTIVE To determine the effect of transportation during periods of high ambient temperature on physiologic and behavioral indices of beef heifers. ANIMALS 20 heifers (mean body weight, 217.8 kg). PROCEDURES Ten heifers were transported 518 km when the maximum ambient temperature was ≥ 32.2°C while the other 10 heifers served as untransported controls. Blood samples were collected from transported heifers at predetermined intervals during the transportation period. For all heifers, body weights, nasal and rectal temperatures, and behavioral indices were measured at predetermined intervals for 3 days after transportation. A week later, the entire process was repeated such that each group was transported twice and served as the control twice. RESULTS Transported heifers spent more time near the hay feeder on the day of transportation, had lower nasal and rectal temperatures for 24 hours after transportation, and spent more time lying down for 2 days after transportation, compared with those indices for control heifers. Eight hours after transportation, the weight of transported heifers decreased 6%, whereas that of control heifers increased 0.6%. At 48 hours after initiation of transportation, weight, rectal temperature, and time spent at various pen locations did not differ between transported and control heifers. Cortisol concentrations were higher 4 hours after initiation of transportation, compared with those determined just prior to transportation. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated transportation during periods of high ambient temperatures caused transient changes in physiologic and behavioral indices of beef heifers.

Effects of weather variables on thermoregulation of calves during periods of extreme heat

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.

Indications for and factors relating to outcome after rumenotomy or rumenostomy in cattle: 95 cases (1999–2011)

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.

Associations of various physical and blood analysis variables with experimentally induced Mycoplasma bovis pneumonia in calves.

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.

Assessment of a commercially available point-of-care assay for the measurement of bovine cardiac troponin I concentration.

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.

Scapulohumeral joint luxation in alpacas: 10 cases (2003-2009).

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.