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African swine fever is a devastating disease of domestic pigs and wild boars caused by African swine fever virus (ASFV). ASFV originates from sub-Saharan African countries. In the last 10 years, the virus left its endemic range to spread to eastern Europe and Russia. On September 2018, Belgian authorities reported that ASFV had been detected in two wild boars in a southern area of the country. One year later, no domestic pig has been infected, with the last ASFV-positive wild boar being confirmed in mid-August 2019, suggesting that the outbreak is now controlled. However, the dispersal dynamics as well as the specific impact of ecological factors and intervention measures on the outbreak remain unknown. In total, 827 positive cases have been reported in wild boar populations. In this study, we exploit the resulting spatio-temporal distribution of occurrence data to investigate the wavefront progression. We first present the application of recently developed methods to quantify the local wavefront velocity of an invading epidemic. Second, we develop and apply a novel analytical framework that uses occurrence data to investigate the impact of ecological factors on the dispersal dynamics of a wavefront progression. Our analyses highlighted that the network of barriers, involving installed fences, had an impact on both the effective dispersal and the wavefront dispersal velocity. Furthermore, we also demonstrated that the wavefront progression was slower outside forest areas. Together, these results have concrete implications for potential future ASFV epidemics in similar regions. Synthesis and applications. We describe a novel analytical approach that exploits occurrence data to investigate the impact of ecological factors on the wavefront velocity and actual wavefront progression. This methodology has the potential to be quickly applied to outbreak datasets solely made of occurrence data, with key benefits for the epidemiological investigations of external spatial factors impacting pathogen dispersal across non-endemic areas. Our analytical workflow could also be further applied to investigate the impact of ecological factors on any kind of biological dispersions (pathogen spreads, invasive species)., SCOPUS: ar.j, info:eu-repo/semantics/published

In southern Belgium, a brown hare ( Lepus europaeus ) was found moribund and killed for ethical reason. The animal was transmitted for postmortem examination. Major histopathological findings consisted of multifocal subacute necrotising meningitis and multifocal subacute necrotising orchitis. Infection with Francisella tularensis was confirmed by both bacteriological isolation and detection by real-time PCR. Further, subtyping of F tularensis colonies stated that it was F tularensis subspecies holarctica biovar I . It is the first case of tularaemia detected in wildlife in Belgium since 2003. The event pushed health professionals to communicate with hunters and other groups with outdoor activities about the Francisella risk and the ways to take care of it, such as wearing gloves to handle found-dead or hunted hares and taking protective measures against tick bites.

Background: Reports of doxycycline-induced toxicity are limited despite common use of this antibiotic to treat infectious respiratory disorders in calves. Objective: To describe previously unreported kidney lesions and diagnostic test results in doxycycline-overdosed calves and to compare these results with other findings reported previously. Animals: Thirty-two calves that presented with adverse effects after receiving high doses of doxycycline as a treatment for mild respiratory disorders. Method: Retrospective review of medical records. Results: Clinical examination identified mainly lethargy, dyspnea, cough, tongue paresia or paralysis associated with dysphagia and sialorrhea, tachycardia, tachypnea, and signs of myopathy. Blood analysis indicated increases in creatine kinase, lactate dehydrogenase, aspartate aminotransferase, and sorbitol dehydrogenase activities and increased serum creatinine and urea concentrations. ECG recordings and Doppler echocardiography examination identified ventricular premature beats and a decrease in left ventricular global and systolic function, respectively. Necropsy and histopathology disclosed necrosis of the myocardium, tongue, and some striated muscles, acute renal tubular necrosis, and fatty degeneration or congestion of the liver. Conclusions: Most of these findings corroborate previous observations made in doxycycline-overdosed calves, and further suggest myocardial and striated muscular toxicity as well as renal toxicity in doxycycline-overdosed calves.

Summary The purpose of the present work is to report the feasibility, humaneness and reliability of a method for measurement of diaphragm performance in intact, awake horses. Phrenic nerves were activated through the vena cava by repeated transvenous stimulations (40 to 80 V, 100 to 200 μs square-wave pulses), using an electrode-catheter advanced from the jugular vein. Twitches were produced that caused changes in gastric and oesophageal pressures, abdominal and rib cage motion and airflow tracings, suggesting that the diaphragm was activated. Four sites were selected over each hemithorax for placement of surface electrodes able to detect and to ensure constancy of evoked compound diaphragmatic action potentials (CDAP). Trains of repeated pulses applied to nerves (10 to 100 Hz) gave repeatable diaphragmatic force-frequency relationships. Nerve stimulation produced no visible signs of discomfort and increases in Cortisol and β-endorphins similar to those produced by nasogastric intubation. Transvenous single and repeated activations of the phrenic nerves in ponies is feasible, free of iatrogenic risks and ethically acceptable, recording reliable evoked potentials via surface electrodes is possible, and force-frequency characteristics of the diaphragm can be conveniently obtained from simultaneous oesophageal and gastric pressures measurements.

DURING the winter 2007/08, an outbreak of unprecedented development lesions of the central nervous system was detected in newborn or stillborn calves and lambs among the routine submissions to the Faculty of Veterinary Medicine, Liege, Belgium, for postmortem examination. The congenital

Summary The effects of an acute non-isocapnic hypoxia on ventilation and pulmonary mechanics were investigated in 6 healthy unsedated Holstein-Friesian (HF) calves and in 7 double-muscled calves of the Belgian White and Blue (BWB) breed known to develop more severe hypoxemia during exercise and respiratory diseases. Data were collected at 1 min intervals throughout the following protocol: breathing air (FIO2 = 21%), then breathing hypoxic gas mixture (FIO2 = 10%) for 5 min, and, finally, breathing air again for 5 min of recovery. Arterial blood was sampled at rest and at the 4th min of hypoxia for blood gas analysis. In HF and BWB calves, hypoxia induced a significant increase in tidal and minute volume, but did not change respiratory rate, dynamic lung compliance and total pulmonary resistance. However, with regard to their ventilation during normoxia at rest, BWB calves showed a comparatively greater rise in ventilation than HF calves during the first 4 min of hypoxia. On the contrary, by the 5th minute of hypoxia, ventilation of BWB calves declined to the normoxic level while HF calves largely sustained hyperventilation. This hypoxic ventilatory depression in BWB calves could be explained by the proportionately greater initial increase in ventilation. It was concluded that BWB calves supported this hypoxic challenge less easily than HF calves.

This study investigated the pattern of growth-induced haemodynamic changes in normal calves during their first year of life. The central venous pressure (CVP), the right ventricular pressure (RVP), the pulmonary arterial pressure (PAP), the pulmonary capillary wedge pressure (PW), the systemic arterial pressure (SAP) and the cardiac output (CO) were measured in 41 healthy Friesian calves. The heart rate (HR), the stroke volume (SV), the cardiac and stroke indices (CI and SI, respectively), the pulmonary and systemic vascular resistance (PVR and SVR, respectively), the right ventricular and left ventricular work (RVW and LVW, respectively) and their corresponding indices (PVRI, SVRI, RVWI and LVWI, respectively) were also measured or calculated. The cardiac output, SV, SAP, PVRI, SVRI, RVW and LVW increased significantly while the HR, CI, PVR, SVR, RVWI and LVWI decreased significantly with somatic growth. The right-sided vascular pressures did not change significantly. The significant increase in systemic arterial pressure may be due to the simultaneous increase in CO. The high CI observed in the first few weeks of life was attributed to a high metabolic rate and might induce a reduced cardiac pumping reserve in young calves. In consequence, a therapeutic inotropic intervention may have little potential benefit at this age.

Summary The purpose of this study was to establish a standardized protocol in order to obtain accurate and reproducible cardiac output (CO) measurements by the thermodilution technique in the unsedated calf. In 5 healthy calves, the effect of various temperatures, volumes, rates, means and sites of injection of the thermal indicator were tested for their effect on accuracy and reproducibility of CO measurement by the thermodilution technique, the Fick method being used as the standard technique. Five milliliters of an iced 5% dextrose solution per 100 kg body weight constituted the correct amount of thermal indicator. Manual injection of the indicator bolus and/or injection of this bolus through the proximal lumen of a thermodilution Swan-Ganz catheter gave poor results of CO measurements by the thermodilution technique. On the other hand, results of CO measurements were highly reliable when the bolus injection was performed by an ECG-synchronized injection pump and/or through a right atrial catheter with a larger diameter and a shorter length than the classical Swan-Ganz catheter. It was concluded that an iced 5% solution of dextrose (5 ml/100 kg body weight) injectated through a right atrial catheter by an ECG-synchronized pump gives the most accurate and reproducible CO measurements by the thermodilution technique in unsedated calves.

Summary The mechanics of breathing was investigated in six healthy calves breathing either air or a mixture of 79% helium and 21% oxygen (He-O2). Intrapleural pressure (Ppl) was measured with an esophageal balloon catheter and transpulmonary pressure was obtained by subtracting the mouth pressure (Pm) from Ppl. Respiratory airflow (V) was measured using a Fleisch pneumotachograph N°3 and tidal volume (Vt) was electronically derived by integrating V with respect to time. Respiratory airflow, Vt, Ppl and Pm were simultaneously recorded while the calves breathed first air (1 min), secondly He-O2 (1 min) and finally air again (1 min). The pulmonary function values were calculated on the tracings and the He-O2 values were compared to the corresponding “air” values. The ventilatory response to resistance unloading was characterized by a significant increase in minute volume exclusively due to an increase in respiratory frequency, while Vt remained unchanged. A decrease of 32% in the total pulmonary resistance (RL) and 16% in the work per litre of ventilation (Wrm/1) were observed when calves breathed He-O2. The effect of the He-O2 on RL and on Wrm/1 suggests that, in the bovine species, airflow turbulences in the upper part of the respiratory tract play a significant role in the total airways resistance.

Seven sport horses were investigated to compare physiological and pharmacological stresses on the plasma glucocorticosteroid levels. Venous blood was sampled and analysed for cortisol concentrations before and after each type of stress. The physiological stress was induced by the completion of a cross-country and the pharmacological one, by an intravenous ACTH administration (200 micrograms) in the same horses, one week after the course. Both exercise and ACTH injection induced a highly significant cortisol increase of 79 +/- 0.10% and 160 +/- 0.18%, respectively. The relative plasma cortisol increases due to exercise on the one hand, and due to ACTH administration on the other hand, were correlated with a coefficient of 0.82. It was concluded that the plasma cortisol increase induced by a standardised pharmacological stress could be used in order to predict the exercise-induced stress response.

ummary The aim of the present experiment was to investigate the hypothesis that there is a respiration-locomotion coupling in trotting equids. Therefore the respiratory airflow (V), the gastric pressure (Pga) and pleural pressure (Ppl) changes and the step frequency (SF) were simultaneously recorded in 5 trotting ponies (body weight: 255±15 kg; age: 3. 5±0. 4 years). Airflow was measured using a Fleisch pneumotachograph fixed on a face mask. Esophageal and gastric balloon catheters coupled to pressure transducers allowed the recording of Ppl and Pga. The exercise was performed on a treadmill and consisted of 1 min walking (1. 5m · s−1), 1 min slow trotting (3. 0m · s−1) (Trot 1) and 3 min fast trotting (3. 5m · s−1) (Trot 2). Data were continuously recorded before and during exercise. At walk and Trot 1, none of the ponies displayed a coupling between SF and the respiratory frequency (RF). In one pony, SF and RF were coupled at a constant ratio of 2:1 during Trot 2 while two other ponies displayed the same coupling only up to the second minute of Trot 2. In the two last ponies, a coupling occurred at the third minute of Trot 2. In all ponies, the peaks in Pga occurring during expiration occurred always simultaneously with the first and/or the second peak V, whether or not there was a relationship between SF and RF. On the other hand, when SF and RF were coupled, the first part of inspiration was always simultaneous to a decrease in Pga. It was concluded that in trotting ponies respiration and locomotion are not always independent and that the abdominal piston may act in synergy with the respiratory pump in some phases of the breathing cycle. Zusammenfassung Synchronisation von Lokomotion und Atmung bei trabenden Ponies Ziel der Untersuchung war es, die Hypothese einer Koppelung zwischen Atmung und Lokomotion bei trabenden Equiden zu prufen. Bei 5 trabenden Ponies (Korpergewicht: 255±15 kg, Alter: 3,5±0,4 Jahre) wurde daher das Atemzeitvolumen (V), die Veranderungen des intragastralen Drucks (Pga) und des pleuralen Drucks (Ppl) sowie die Schnittfrequenz (SF) gleichzeitig registriert. Das Atemzeitvolumen wurde mit einem an einer Gesichtsmaske fixierten Pneumotochographen nach Fleisch gemessen. Jeweils an einen Druckwandler angeschlossene Osophagus- bzw. Magen-Ballon-katheter ermoglichten die Aufzeichnung des Ppl und des Pga. Die Bewegung der Tiere erfolgte auf einem Laufband und umfaste einminutiges Gehen (1,5m · s−1), einminiitiges langsames Traben (3,0m · s−1) (Trab 1) und dreiminiitiges schnelles Traben (3,5m · s−1) (Trab 2). Die Daten wurden vor und wahrend der Bewegung kontinuierlich registriert. Beim Gehen und beim Trab 1 ergab sich bei keinem der Ponies eine Koppelung zwischen SF und Respirationsfrequenz (RF). Wahrend des Trabes 1 waren SF und RF bei einem Pony konstant im Verhaltnis 2:1 gekoppelt, wahrend zwei weitere Ponies diese Koppelung nur bis zur zweiten Minute des Trabes 2 aufwiesen. Bei den anderen zwei Ponies ergab sich eine entsprechende Koppelung in der dritten Minute des Trabes 2. Bei alien Ponies trat der wahrend der Exspiration zu verzeichnende Peak des Pga unabhangig von der Beziehung zwischen SF und RF immer gleichzeitig mit dem ersten und/oder zweiten Peak von V auf. Bei einer Koppelung von SF und RF fiel andererseits der erste Abschnitt der Inspiration immer mit einer Verringerung des Pga zusammen. Es wird geschlossen, das beim trabenden Pony Atmung und Lokomotion nicht immer unabhangig voneinander sind und das wahrend einiger Phasen des Atmungszyklus die sich wie ein Kolben verhaltenden abdominalen Eingeweide synergistisch zur respiratorischen “Pumpe” verhalten.

FIELD veterinarians refer approximately 2200 dead animals per year for postmortem examination to the University of Liege's Faculty of Veterinary Medicine. In March 2013, a seven-year-old Belgian blue cow was referred with a history of depression, anorexia, weight loss and purulent metritis that did not respond to standard antibiotic therapies. Postmortem examination revealed severe emaciation (cachexia), chronic …

IN Belgium, the end of 2011 and beginning of 2012 were characterised by numerous reports of births at term of calves with neurological signs or malformations of the head, spine or limbs that were subsequently assigned to the emerging Schmallenberg virus (SBV) (Garigliany and others 2012a). Further, the large-scale cross-sectional serological surveys conducted in cattle during spring 2012 concluded that almost all Belgian cattle had already been in contact with the virus (Garigliany and others 2012b, Meroc and others 2013). As the immunity raised by the cow against close phylogenetic …