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In 2 previous publications (Planta and De Meester, 2007; De Meester et al., 2008) the value of the socially acceptable behavior (SAB) test as a temperament test was examined. In this study, the postures and behavioral strategies of 171 dogs in the SAB test were analyzed. All dogs were tested by the same test team, on the same location, and with the same test materials. Factor analysis of the results revealed that 2 underlying factors, presence and absence of the owners, explained 64% of the total variance in the test scores. The significant correlation between the SAB scores in the different subsequent subtests indicates that in addition to the nature of the stimulus, the posture is also influenced by the preceding subtest. In a cluster analysis, the outcome with 5 different clusters turned out to be stable. This allows us to categorize dogs more precisely than that presented in a study by De Meester et al. (2008) with respect to their reaction in potentially aversive situations in the presence or absence of the owners. Most dogs that threaten or bite other dogs in the test will have a high posture, although a high percentage of dogs in a very low position will bite too. Most dogs that bite the doll or hand will have a low posture in the specific subtests, indicating that the emotion behind this action is fear. On the basis of the low predictive values we can state that it is not possible to obtain all information regarding bite and/or flight behavior later in the test, only from the strategies or SAB scores ≥5 of the dogs in the subtests. If all the information is to be obtained, we have to perform all subtests. As a consequence, some dogs will bite or panic and flee in the test. It will be important to manage these behaviors in such a way that the dog has neither learning experience for aggression, nor suffers too much from fear. A protocol for desensitization and counter-conditioning must be available and the test must be stopped immediately if it adversely affects the welfare of the dog. In a process of ethical balancing, the value of the test must be weighted against its possible negative influences on the dog.

Live weight is an important trait in cattle farming. Weighing is not always feasible and therefore live weight is often estimated from easily accessible data. In this study, data on live weight, age and gender, and four body measurements, withers height (WH), heart girth (HG) and width of the shoulders (SW) and hind quarters (BcW) of double-muscled Belgian Blue beef (DM-BBB) farm animals were used to develop multivariable non-linear and linear regression models that predict live weight from these easily accessible data. The relationship between the logarithm of the live weight and the logarithm of time is adequately described by a general logistic function. The age period from 100 to 600 days of age is contained in the linear part of the logistic function. This region is of particular economic interest because it contains the yearling age and slaughter age that are important in DM-BBB breeding and management. Adding one of the body traits in the linear models that contain age and gender as fixed effects decreases the coefficient of variation. A model with withers height and shoulder width has the lowest coefficient of variation, with no further significant improvement when adding either heart girth or width of the hind quarters.

A report of the Scientific Committee on Animal Health and Animal Welfare of the European Commission (CEC, 1999.) includes recommendations for setting up monitoring programmes for classical swine fever (CSF) infection in a wild-boar population, based on the assumption that one would detect at least 5% prevalence in a CSF-infected wild-boar population. This assumption, however, is not science based. We propose an alternative method to provide evidence for a wild-boar population being free of CSF and evaluate the efficiency of a surveillance programme that was implemented in Belgium in 1998. In our study, the probability of freedom of CSF-virus was estimated based on 789 samples; these were collected from wild-boars within the surveillance programme (within the three provinces which include 95% of the Belgian wild-boar population) and examined by three diagnostics methods (antibody detection, virus detection and virus RNA detection). A Bayesian framework was used for the estimation, accounting for the diagnostic test characteristics without the assumption of the presence of a gold standard. The median probability of freedom of CSF-virus was estimated at 0.970, with a 95% credibility interval of 0.149–1.000. Independent on the choice of the prior information, the posterior distributions for the probability of freedom of CSF-virus were always skewed close to the upper boundary of 1. This represents a big gain of knowledge since we did not use any prior information for the probability of freedom of CSF-virus and took the uncertainty about the accuracy of the diagnostic methods into account.

At present, two types of vaccines against classical swine fever (CSF) virus are commercially available: E2 sub-unit marker vaccines and the conventional attenuated live C-strain vaccines. To evaluate the reduction of the horizontal virus transmission, three comparable experiments were carried out in which groups of weaner pigs (vaccinated with a marker vaccine or a C-strain vaccine) were challenged with CSF virus at 0, 7, and 14 days post-vaccination (dpv). Virus transmission was prevented totally when the challenge occurred at 14 dpv with an E2-marker vaccine (0/12 contact pigs positive in virus isolation (VI); R = 0 (0; 1.5)). At 7 dpv, transmission was reduced slightly (5/12 contact pigs positive in VI; R = 1.0 (0.3; 3.0)), whereas at 0dpv, vaccination had no effect on transmission (10/12 contact pigs positive in VI; R = 2.9 (1.5; 10.8)). In the C-strain-vaccinated pigs, no virus transmission was detected even when the challenge was performed at the same day as the vaccination (0/12 contact pigs positive in VI; R = 0 (0; 1.5)).

To investigate the cardiopulmonary effects of a xylazine-guaiphenesin-ketamine infusion combined with inter-coccygeal extradural (lidocaine) anaesthesia in calves.Prospective study.Five Holstein Friesian calves (one steer, four heifers) aged 6 weeks weighing 65.2 +/- 2.7 kg.Calves were anaesthetized with isoflurane in oxygen for instrumentation. At least 12 hours later, xylazine (0.2 mg kg(-1) i.m.) was given. After 15 minutes, an infusion of xylazine hydrochloride (0.1 mg mL(-1)), guaiphenesin (50 mg mL(-1)) and ketamine (1 mg mL(-1)) (X-G-K) was infused at a rate of 1.1 mL kg(-1) hour-1 i.v. Oxygen (4 L minute(-1)) was delivered by nasotracheal tube 30 minutes later. Inter-coccygeal (Co1-Co2) extradural anaesthesia (lidocaine 2%, 0.18 mL kg(-1)) was administered 30 minutes later. Cardiopulmonary variables were obtained in the unsedated standing calves 10 minutes after xylazine, 15 and 30 minutes after X-G-K without O2, 15 and 30 minutes after X-G-K with O2 and 5, 15, 30, 45 and 60 minutes after extradural anaesthesia. Data were analysed using a repeated measurement analysis of variance including an autoregressive covariance structure of order 1 (correlations at different time intervals).Xylazine caused significant (p0.05) decreases in heart rate (HR), cardiac output (Qt) and index (CI), stroke volume and stroke index, mean, systolic and diastolic arterial blood pressure (MAP, SAP, DAP), left (LVWSI) and right ventricular stroke work index (RVWSI), mean, systolic and diastolic pulmonary arterial pressure (MPAP, SPAP, DPAP), arterial pH, arterial oxygen tension (PaO2), arterial base excess, arterial HCO3- concentration, arterial saturation, packed cell volume, arterial and venous oxygen content (CaO2, CvO2), O2 consumption and O2 delivery (VO2, DO2). Increases in systemic vascular resistance (SVR) and pulmonary vascular resistance (PVR) were observed. During X-G-K infusion without O2, HR, Qt and CI increased gradually while SVR, PVR and MAP decreased. Left ventricular stroke work index and PaO2 remained constant, while O2 supplementation improved PaO2. Coccygeal extradural anaesthesia had little effect on cardiopulmonary variables. Respiratory rate (f) and PaCO2 significantly increased over the experiment.Xylazine caused adverse cardiopulmonary effects in calves. Improvement occurred during xylazine-guaiphenesin-ketamine infusion. Cardiac index and arterial blood pressure remained below baseline values while sustained increases in respiration rate and PaCO2 were observed. Inter-coccygeal extradural anaesthesia had only minor effects. Oxygen supplementation proved advantageous during guaiphenesin, ketamine and xylazine infusion in healthy calves in combination with coccygeal extradural anaesthesia induced persistent cardiopulmonary depression.

A high number of dairy heifers freshen with udder health problems. The prevalence of teat apex colonization (TAC) with Staphylococcus chromogenes , one of the most widespread coagulase-negative staphylococci (CNS) in milk samples from freshly calved dairy heifers, was measured cross-sectionally in non-lactating heifers on eight commercial dairy farms in Belgium. The influence of age on this prevalence, and the association between teat apex colonization with S. chromogenes prepartum and quarter milk somatic cell count (SCC) in early lactation were studied. In total, 492 teat apices were sampled from 123 heifers. The age of the heifers varied from 8 to 34 months. Overall, 20% of the heifers had at least one teat apex colonized with S. chromogenes . Of all teats sampled, 10% were colonized with S. chromogenes . The chance of having at least one teat apex colonized with S. chromogenes increased with age of the heifer. The presence of prepartum teat apex colonization with S. chromogenes was not associated with intramammary infection (IMI) early postpartum with the same bacterium. On the contrary, teat apex colonization with S. chromogenes prepartum appeared to protect quarters in the first few days of lactation from having somatic cell count ≥200,000 cells/ml milk, commonly accepted as the threshold for intramammary infection.

The clinical and virological protection induced by an E2 sub-unit marker-vaccine against Classical Swine Fever (CSF) was examined during an experimental infection in vaccinated and non-vaccinated pigs. Forty-five pigs were equally distributed over three adjacent pens of an isolation unit, there was only indirect (airborne) contact between pigs in the different pens. In pen 3 all pigs were vaccinated twice with 4 weeks interval. Pigs in pens 1 and 2 were not vaccinated. Two weeks after booster vaccination, one randomly selected pig in the middle pen was experimentally inoculated with CSF virus. After the initial virus spread in the infected pen, all pigs in the non-vaccinated adjacent pen were infected. In the vaccinated pen, seven out of 14 pigs became infected during the experiment. Survival analysis showed that virus transmission by direct and indirect contact was significantly (p

Coagulase-negative staphylococci from cases of bovine mastitis were identified to species level by using an identification scheme based on a three-plate test system which tested for DNase on DNA agar, for protease on calcium caseinate agar, and for the organism's sensitivity to novobiocin, desferrioxaminine (deferoxamine) and fosfomycin by agar diffusion tests. Testing for the inhibition of Staphylococcus delta haemolysin (Skalka 1991) can replace the protease tests.