Temperatures of storage areas in large animal veterinary practice vehicles in the summer and comparison with drug manufacturers' storage recommendations.

BACKGROUND: Large animal veterinarians carry drugs in their practice vehicles in storage areas that are not typically refrigerated. The most common upper limits of manufacturers' storage temperatures for United States (U.S.)-approved non-refrigerated drugs are 25 or 30 °C. Because ambient temperatures in many locations in the U.S. exceed these temperatures during the summer, we measured storage area temperatures over 4 months in the summer of 2013 to evaluate the extent to which labeled storage temperatures are exceeded. METHODS: A convenience sample of 12 vehicles from 5 central Texas practices and 12 vehicles from 4 south central Nebraska practices was used. Temperatures were recorded in one drug storage compartment in each vehicle from May 15 - September 16, 2013, at 15-minute intervals using a self-contained, battery operated temperature recording device. RESULTS: The highest temperatures recorded in a storage unit were 54.4 and 47.7 °C in Texas and Nebraska, respectively. The mean temperature recorded across all 24 storage units was 29.1 °C, with a mean of 26.9 °C in Nebraska and 31.4 °C in Texas. In Nebraska, at least one temperature over 25 °C was recorded on a mean of 111/124 days and a mean of 63 % of total logger readings. In Texas, temperatures over 25 °C were recorded on a mean of 123/124 days and a mean of 95 % of total logger readings. CONCLUSIONS: Temperatures in storage units in participating veterinary practice vehicles exceeded labeled drug storage temperatures a significant portion of the summer of 2013. More research is needed to determine whether these excursions above the manufacturers' recommended storage temperatures alter efficacy of stored drugs.

Synovial fluid pharmacokinetics of tulathromycin, gamithromycin and florfenicol after a single subcutaneous dose in cattle.

BACKGROUND: Deep digital septic conditions represent some of the most refractory causes of severe lameness in cattle. The objective of this study was to determine the distribution of tulathromycin, gamithromycin and florfenicol into the synovial fluid of the metatarsophalangeal (MTP) joint of cattle after single subcutaneous administration of drug to evaluate the potential usefulness of these single-dose, long-acting antimicrobials for treating bacterial infections of the joints in cattle. RESULTS: Twelve cross-bred beef cows were randomly assigned to one of the drugs. Following subcutaneous administration, arthrocentesis of the left metatarsophalangeal joint was performed at various time points up to 240 hours post-injection, and samples were analyzed for drug concentration. In synovial fluid, florfenicol pharmacokinetic parameters estimates were: mean Tmax 7 +/- 2 hours, mean t½ 64.9 +/- 20.1 hours and mean AUC0-inf 154.0 +/- 26.2 ug*h/mL. Gamithromycin synovial fluid pharmacokinetic parameters estimates were: mean Tmax 8 hours, mean t½ 77.9 +/- 30.0 hours, and AUC0-inf 6.5 +/- 2.9 ug*h/mL. Tulathromycin pharmacokinetic parameters estimates in synovial fluid were: Tmax 19 +/- 10 hours, t½ 109 +/- 53.9 hours, and AUC0-inf 57.6 +/- 28.2 ug h/mL. CONCLUSIONS: In conclusion, synovial fluid concentrations of all three antimicrobials were higher for a longer duration than that of previously reported plasma values. Although clinical data are needed to confirm microbiological efficacy, florfenicol achieved a synovial fluid concentration greater than the MIC90 for F. necrophorum for at least 6 days.

Continuous low-dose infusion of tumor necrosis factor alpha in adipose tissue elevates adipose tissue interleukin 10 abundance and fails to alter metabolism in lactating dairy cows.

Repeated bolus doses of tumor necrosis factor-α (TNFα) alters systemic metabolism in lactating cows, but whether chronic release of inflammatory cytokines from adipose tissue has similar effects is unclear. Late-lactation Holstein cows (n=9-10/treatment) were used to evaluate the effects of continuous adipose tissue TNFα administration on glucose and fatty acid (FA) metabolism. Cows were blocked by feed intake and milk yield and randomly assigned within block to control or TNFα treatments. Treatments (4mL of saline or 14µg/kg of TNFα in 4mL of saline) were infused continuously over 7d via 2 osmotic pumps implanted in a subcutaneous adipose depot. Plasma, milk samples, milk yield, and feed intake data were collected daily, and plasma glucose turnover rate was measured on d 7. At the end of d 7, pumps were removed and liver and contralateral tail-head adipose biopsies were collected. Results were modeled with the fixed effect of treatment and the random effect of block. Treatment with TNFα increased plasma concentrations of the acute phase protein haptoglobin, but did not alter plasma TNFα, IL-4, IL-6, or IFN-γ concentrations, feed intake, or rectal temperature. Milk yield and composition were unchanged, and treatments did not alter the proportion of short- versus long-chain FA in milk on d 7. Treatments did not alter plasma free FA concentration, liver triglyceride content, or plasma glucose turnover rate. Surprisingly, TNFα infusion tended to decrease liver TNFα and IL-1 receptor 1 mRNA abundance and significantly increased adipose tissue IL-10 protein concentration. Continuous infusion of TNFα did not induce the metabolic responses previously observed following bolus doses delivered at the same rate per day. Metabolic homeostasis may have been protected by an adaptive anti-inflammatory response to control systemic inflammation.

Level of and motivation for extracurricular activity are associated with academic performance in the veterinary curriculum.

The objectives of this project were to determine the number of school-sanctioned extracurricular opportunities available to veterinary students and characterize the policies of school administrations toward extracurricular involvement and academic standing. Further, we sought to describe the level of extracurricular involvement of veterinary students, determine the association between extracurricular activity involvement and academic performance, and determine the motivation for extracurricular involvement of veterinary students. Survey data were obtained from 18 associate deans of colleges of veterinary medicine regarding the number of extracurricular student organizations within their school and administrative recommendations regarding student involvement. Another survey was administered and responded to by 665 veterinary students enrolled in curricular years 1-3 at Kansas State University and Texas A&M University regarding their extracurricular involvement. Associate deans of 11 schools responded that they make formal or informal recommendations to students about extracurricular activities, workload, and academic priority (61.1%). In a multivariate model, students who participated two times per week or more had a significantly higher overall grade point average (GPA) than students participating once per week (p<.0500). Students for whom the primary reason for participation was networking or social enhancement had a significantly lower overall GPA than students for whom the primary reason was gaining new knowledge and skills (p<.0500). These results indicate that student extracurricular involvement is a consideration for administrators when counseling students in academic difficulty. Moderate levels of extracurricular involvement can contribute to the academic success of students, but students should temper their level of involvement based upon their own motivations.

Investigation into the impact of audience response devices on short- and long-term content retention.

Audience Response Systems (ARSs) may enhance short-term knowledge retention. Long-term knowledge retention is more difficult to demonstrate. According to previous studies, ARS questions requiring application of knowledge or peer interaction are more effective in maintaining student attention. The purpose of this study was to determine if peer discussion or individual-knowledge questions enhance short- and/or long-term knowledge retention. Third-year veterinary students responded to ARS questions posed in individual knowledge (n=3 questions) and peer discussion (n=3 questions) format from six different instructors. To test short-term memory, the same questions were delivered during the course examination (within 21 days). To test long-term retention, these questions were posed during a retention exercise (four months later). On the course examination, students had a higher (p<.01) probability (±SE) of correctly answering ARS individual-knowledge questions (93.8 ± 1.8%) compared to novel (previously unseen, non-ARS control) course examination questions (87.5 ± 3.1%), but the probability of correctly answering examination questions previously posed using ARS peer discussion format (89.5 ± 3.0%) did not differ from individual knowledge or novel examination questions. The positive impact of ARS-knowledge questions was not maintained through the retention exercise. Neither individual knowledge (70.5 ± 6.4%) nor peer-discussion questions (67.5 ± 6.9%) performed better on the retention exercise than the questions that appeared only on the course examination (68.6 ± 6.1%). Curricular strategies that emphasize content review may be more powerful than strategies that strengthen initial learning for long-term content retention.

Use of dietary cation anion difference for control of urolithiasis risk factors in goats.

OBJECTIVE: To determine correlations between dietary cation anion difference (DCAD) and urine pH, urine specific gravity, and blood pH in goats. ANIMALS: 24 crossbred goat wethers. PROCEDURES: Goats were randomly assigned to 1 of 4 DCAD groups (-150, -75, 0, or +75 mEq/kg of feed) and fed pelleted feed and ground hay for 7 days. The diet was then supplemented with ammonium chloride to achieve the assigned DCAD of each group for 7 days. Urine was obtained for pH and specific gravity measurements at hours -3 to -1, 1 to 3, 5 to 7, 9 to 11, and 13 to 15 relative to the morning feeding. Blood pH was determined on alternate days of the study period. RESULTS: Goats in the -150 and -75 mEq/kg groups had a urine pH of 6.0 to 6.5 two days after initiation of administration of ammonium chloride, and urine pH decreased to < 6.0 by day 7. Goats in the 0 mEq/kg group had a urine pH from 6.0 to 6.5 on day 5, whereas urine pH in goats in the +75 mEq/kg group remained > 6.5 throughout the trial. Urine specific gravity differed only between the -150 mEq/kg and the -75 mEq/kg groups. Blood pH in the -150 mEq/kg group was significantly lower than that in the other groups. CONCLUSIONS AND CLINICAL RELEVANCE: Goats in the 0 mEq/kg DCAD group had a urine pH of 6.0 to 6.5 five days after intitiation of feeding the diet, and that pH was maintained through day 7, without significant reduction in blood pH. This may serve as a target for diet formulation for the prevention of urolithiasis.

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.

An experimental model for calcium carbonate urolithiasis in goats.

BACKGROUND: Calcium carbonate is a common urolith type in small ruminants with no high-yield experimental model to evaluate animal susceptibility or preventative measure response. HYPOTHESIS: That novel plastic winged implants would allow accumulation and quantification of calcium carbonate calculus formation in goats on a high-calcium diet and identify individual variation between goats in the mass of calculi produced. ANIMALS: Eight nonpregnant 3- and 4-year-old Boer-cross does, weighing 22.3-39.5 kg, determined to be healthy based on physical examination, were used in these experiments. METHODS: Prospective cohort study for in vivo experimental model development. Implants were placed into the urinary bladder lumen in 8 goats over 2 evaluation periods. The alfalfa-based ration had a total ration Ca : P of 3.29 and 3.84 : 1, respectively. Urine was collected at 0, 28, 56, and 84 days in the 1st experiment; blood and urine at those timepoints in the 2nd experiment. For each evaluation period, the implants were removed 84 days after implantation and weighed. Accumulated calculi mass was calculated and compared between goats and was analyzed for composition. RESULTS: Implant retention was 100% and 86% in the 2 studies. All goats with retained implants accumulated calcium carbonate at a mean implant gain per day across studies ranging from 0.44 to 57.45 mg. Two goats accumulated (0.44-7.65 mg/day and 33.64 & 57.45 mg/day) significantly more urolith material than the cohort across both studies (P = .047). No routine analytes on blood or urine were found to be explanatory for the difference observed. CONCLUSIONS AND CLINICAL IMPORTANCE: These findings form a basis for implant and diet selection for use in future studies of urolithiasis development and for studies regarding individual susceptibility to urolithiasis.

Evaluation of the ruminant complete blood cell count.

The complete blood cell count can provide valuable diagnostic and prognostic information when coupled with a thorough physical examination. This article addresses proper sample handling, storage, and interpretation of the erythron, serum iron indices, leukon, and acute-phase proteins for cattle, sheep, and goats.

Use of grid keratotomy for the treatment of indolent corneal ulcer in a llama.

A case of indolent corneal ulcer in a llama (Llama glama) is described. Diagnostic testing included a complete ophthalmic examination with corneal cytologic and histopathologic examination. Successful management involved grid keratotomy and topical application of neomycin-polymixin-bacitracin and atropine 1% ointments. Weekly follow-up examinations are described until healing was considered complete.

Chondrosarcoma of the scapula of an 8-month-old Holstein steer.

Malignant neoplasms occur commonly in cattle, with lymphosarcoma being the most common. Chondrosarcoma rarely has been described and only in mature cattle. The present report describes a chondrosarcoma of the left scapula of an 8-month-old Holstein steer. Histologic examination of the mass revealed an unencapsulated, multilobular neoplasm composed of neoplastic spindle cells embedded in irregular islands of chondroid matrix, consistent with a diagnosis of chondrosarcoma.