Forecasting clinical disease in pigs: comparing a naive and a Bayesian approach

In veterinary practice the clinician often evaluates and predicts herd health status over time according to clinical criteria. In this paper, we modeled three different clinical signs among pigs based on longitudinal clinical observations in 15 pig herds. We compared and discussed the outputs from two different approaches for making clinical forecasts in a herd: a naive approach using a simple time series model with previous disease observations as predictors and a Bayesian state space models approach, in which the time lag variable entered into the random component of the model. We used the Markov chain Monte Carlo technique to calculate posterior distributions of the forecasts. For the herd specific forecasts the results showed that there were only minor differences between the forecasts from the simple time series model and the median forecasts from the Bayesian model. However, the credibility intervals from the Bayesian model were wider than the forecasts from the simple model and, therefore the Bayesian model encompassed the variability in the forecasts better. Compared to the statistical model, the simple time series would be easier to implement in a practical setting. However, the latter lacks the inherent “generality” from the statistical model that allows the user to make statements about the distribution of the herds and to predict disease status based on the “average” correlation among the herds. The applicability of the Bayesian approach within a clinical decision-making framework was discussed, with special emphasis on the use of prior information and clinical forecasting.     

Postoperative assessment of surgical clip position in 16 dogs with cancer: a pilot study

Metallic hemoclips or surgical staples were inserted in 16 tumor-bearing dogs at the time of surgical resection of the tumor. Orthogonal radiographs were taken immediately postoperatively and after wound healing to visualize the location and number of hemoclips or metallic staples. A shift in hemoclip/staple position was identified in nine dogs, mainly from positioning during radiography. In three dogs, an absolute shift in marker position was identified. Based on this study, it appears that the placement of surgical clips is potentially useful in identifying the tumor bed, which may be of benefit in establishing radiation treatment fields.     

Developing a classification tool based on Bloom's taxonomy to assess the cognitive level of short essay questions

The cognitive level of short essay questions taken from assessments of two veterinary courses at the Faculty of Veterinary Medicine of Utrecht University (FVMU) was evaluated using a simplified classification tool based on the taxonomy of Bloom. Classifications were made by teaching staff members (subject matter experts, or SME) and by faculty members not involved in teaching the course (non-subject matter experts, or NSME). To compare the cognitive level assigned by raters in the SME group to that assigned by the NSME group, each test item was assigned a modal taxonomic level. The results indicate that the agreement level between a pair of raters within a group (SME or NSME) differed (34% to 77% and linear weighted Cohen's kappa coefficient 0.12 to 0.60). The agreement level on the modal taxonomic level between the SME and NSME groups for the two courses was 65% and 73%, with a linear weighted Cohen's kappa coefficient of 0.43 and 0.63 respectively. The requirement of expertise of a subject for classification is discussed. The introduction of the classification tool had a positive effect on teaching staff members' awareness of the importance of the cognitive level of assessments. Improvements to the classification tool to obtain higher agreement levels are proposed.     

Curriculum development in the Netherlands: introduction of tracks in the 2001 curriculum at Utrecht University, The Netherlands

The Faculty of Veterinary Medicine in Utrecht has recently introduced two major curriculum changes in order to keep pace with developments in research (the vast increase in scientific knowledge), in society (the quality awareness of veterinary clients), and in the veterinary profession, where a species and sector differentiation can be observed. After about 15 years during which the curriculum remained more or less unchanged, a radical curriculum revision was introduced in 1995. A further revision, with the introduction of separate study tracks, began in 2001. The 2001 curriculum focuses on academic and scientific training, active learning and problem solving, training in communication and professional behavior, and lifelong learning. It is divided into a four-year core curriculum, in which a broad, cross-species pathobiological insight is central, and a two-year track curriculum, through which students achieve a starting competence in a specific species or sector. The main teaching methods are tutorials and group tasks; practical work is used mainly to achieve specific veterinary skills. Teaching hours represent 30-35% of all study hours. Self-teaching is encouraged by providing study materials, self-teaching questions, teachers assigned to assist with self-teaching, and adequate facilities. The five tracks offered are Companion Animals/Equine; Food Animals; Veterinary Public Health; Veterinary Research; and Veterinary Administration and Management. All students follow a uniform 30-week clinical rotation program, while the track program is 42 weeks. A summary of admission procedures is given, as well as the times and procedures for track selection.     

Effect of dietary soy on serum thyroid hormone concentrations in healthy adult cats

OBJECTIVE: To compare effects of short-term administration of a soy diet with those of a soy-free diet on serum thyroid hormone concentrations in healthy adult cats. ANIMALS: 18 healthy adult cats. PROCEDURE: Cats were randomly assigned to receive either a soy or soy-free diet for 3 months each in a crossover design. Assays included CBC, serum biochemical profile, thyroid hormone analysis, and measurement of urinary isoflavone concentrations. RESULTS: Genistein, a major soy isoflavone, was identified in the urine of 10 of 18 cats prior to dietary intervention. Compared with the soy-free diet, cats that received the soy diet had significantly higher total thyroxine (T4) and free T4 (fT4) concentrations, but unchanged total triiodothyronine (T3) concentrations. The T3/fT4 ratio was also significantly lower in cats that received the soy diet. Although the magnitudes of the increases were small (8% for T4 and 14% for fT4), these changes resulted in an increased proportion of cats (from 1/18 to 4/18) that had fT4 values greater than the upper limit of the laboratory reference range. There was no significant effect of diet on any other measured parameter. CONCLUSIONS AND CLINICAL RELEVANCE: Short-term administration of dietary soy has a measurable although modest effect on thyroid hormone homeostasis in cats. Increase in T4 concentration relative to T3 concentration may result from inhibition of 5'-iodothyronine deiodinase or enhanced T3 clearance. Soy is a common dietary component that increases serum T4 concentration in cats.     

In vitro effects and in vivo efficacy of a novel cyclooxygenase-2 inhibitor in dogs with experimentally induced synovitis

OBJECTIVE: To determine cyclooxygenase-2 (COX-2) selectivity, pharmacokinetic properties, and in vivo efficacy of ML-1,785,713 in dogs. ANIMALS: 21 healthy male and female mixed-breed dogs and 24 healthy male Beagles. PROCEDURE: Selectivity of ML-1,785,713 for inhibiting COX-2 was determined by comparing the potency for inhibiting cyclooxygenase-1 (COX-1) with that of COX-2 in canine blood. Pharmacokinetic properties were determined after i.v. (2 mg/kg) and oral (8 mg/kg) administration in female mixed-breed dogs. In vivo efficacy was evaluated in male mixed-breed dogs with urate crystal-induced synovitis. Prophylactic efficacy was evaluated by administering ML-1,785,713 two hours before induction of synovitis whereas therapeutic efficacy was determined by administering ML-1,785,713 one hour after induction of synovitis. RESULTS: Blood concentrations that resulted in 50% inhibition of COX-1 and COX-2 activity in vitro were 119.1 microM and 0.31 microM, respectively, and selectivity ratio for inhibiting COX-2 relative to COX-1 was 384. ML-1,785,713 had high oral bioavailability (101%), low systemic clearance (77 mL/min/kg), and an elimination half-life of 5.9 hours. ML-1,785,713 was efficacious when administered prophylactically and therapeutically to dogs with urate crystal-induced synovitis. CONCLUSIONS AND CLINICAL RELEVANCE: ML-1,785,713 is a novel, potent COX-2 inhibitor that is the most selective COX-2 inhibitor described for use in dogs to date. ML-1,785,713 has oral bioavailability and low systemic clearance that is comparable to other non-steroidal anti-inflammatory drugs. It is effective after prophylactic and therapeutic administration in attenuating lameness in dogs with urate crystal-induced synovitis. Drugs that specifically inhibit COX-2 and not COX-1 at therapeutic doses may have an improved tolerability profile, compared with nonselective non-steroidal anti-inflammatory drugs.     

Effects of a whole-body spandex garment on rectal temperature and oxygen consumption in healthy dogs

OBJECTIVE: To determine whether a full-body spandex garment would alter rectal temperatures of healthy dogs at rest in cool and warm environments. DESIGN: Prospective study. ANIMALS: 10 healthy dogs. PROCEDURES: Each dog was evaluated at a low (20 degrees to 25 degrees C [68 degrees to 77 degrees F]) or high (30 degrees to 35 degrees C [86 degrees to 95 degrees F]) ambient temperature while wearing or not wearing a commercially available whole-body spandex garment designed for dogs. Oxygen consumption was measured by placing dogs in a flow-through indirect calorimeter for 90 to 120 minutes. Rectal temperature was measured before dogs were placed in the calorimeter and after they were removed. RESULTS: Rectal temperature increased significantly more at the higher ambient temperature than at the lower temperature and when dogs were not wearing the garment than when they were wearing it. The specific rate of oxygen consumption was significantly higher at the lower ambient temperature than at the higher temperature. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that wearing a snug spandex body garment does not increase the possibility that dogs will overheat while in moderate ambient temperatures. Instead, wearing such a garment may enable dogs to better maintain body temperature during moderate heat loading. These results suggest that such garments might be used for purposes such as wound or suture protection without causing dogs to overheat.     

Detection of airborne Salmonella enteritidis in the environment of experimentally infected laying hens by an electrostatic sampling device

Bacteriologic culturing of environmental samples taken from sources such as manure pits and egg belts has been the principal screening tool in programs for identifying commercial laying flocks that have been exposed to Salmonella enteritidis and are thus at risk to produce contaminated eggs. Because airborne dust and aerosols can carry bacteria, air sampling offers a potentially efficient and inexpensive alternative for detecting S. enteritidis in poultry house environments. In the present study, an electrostatic air sampling device was applied to detect S. enteritidis in a room containing experimentally infected, caged laying hens. After oral inoculation of hens with a phage type 13a S. enteritidis strain, air samples were collected onto agar plates with the electrostatic sampling device, an impaction air sampler, and by passive exposure to the settling of aerosols and dust. Even though the floor of the room was cleaned once per week (removing most manure, dust, and feathers), air samples were positive for S. enteritidis for up to 4 wk postinoculation. On the basis of both the number of S. enteritidis colonies observed on incubated agar plates and the frequency of positive results, the efficiency of the electrostatic device was significantly greater than that of the passive exposure plates (especially at short collection intervals) and was similar to that of the far more expensive impaction sampler. The electrostatic device, used for a 3-hr sampling interval, detected airborne S. enteritidis on 75% of agar plates over the 4 wk of the study.