La valorisation de la production laitière

peer reviewe

Phenotype and genetic parameters of somatic cell counts in the Belgian black and white breed

peer reviewe

Association of milk protein polymorphisms with milk production traits in two belgian dairy breeds using an animal model

peer reviewe

Experimental rotavirus diarrhoea in colostrum-deprived newborn calves: assay of treatment by administration of bacterially produced human interferon (Hu-IFN alpha 2).

Seven colostrum-deprived newborn calves were orally inoculated within 24 hours after birth with bovine rotavirus. Three of them were intramuscularly injected with bacterially produced human interferon (Hu-IFN alpha 2). The four control animals presented a severe diarrhoea for at least 48 hours, while only one of the treated calves suffered from a transient diarrhoea for a few hours. Hu-IFN alpha 2 seems therefore able to control rotavirus diarrhoea in newborn calves, although it did not inhibit virus excretion and seroconversion in the treated animals. Moreover, the administration of endogenous interferon appeared to be well tolerated by newborn calves. The efficacy of human alpha 2 interferon for the treatment of this important virus infection of cattle seems thus well established

Les attentes des consommateurs, des nouveaux critères de sélection porcine

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Descriptive study of the morphometric and genital characteristics of goats in Lubumbashi in the Democratic Republic of Congo

The study aimed to determine zootechnical and reproduction characteristics of female (n = 1311) and male (n = 346) goats slaughtered in Lubumbashi. Height at withers, body length and live weight were 53 cm, 77 cm and 20.5 kg in females, and 53 cm, 71 cm and 19 kg in males, respectively. The left and right testicular weights, diameter of testes and scrotal perimeter were 67.3 g, 66.9 g, 12 cm and 21.1 cm, respec­tively. The mean length of the genital tract from the vulva to the end of the horn was 30.3 cm. The mean weight of ova­ries, length and width of left and right ovaries were 1.1 g, 1.8 x 1.3 cm and 1.7 x 1.3 cm, respectively. No cystic struc­ture was observed on the ovaries. Forty-four percent of the slaughtered females were found pregnant. From the compari­son of the number of corpora lutea and of embryos or fetuses in the womb, embryonic mortality was estimated at 19.2%

Comparative study of the body surface electrocardiogram in double-muscled and conventional calves.

The purpose of this work was to study electrocardiographic features of double-muscled beef cattle. Electrocardiograms were recorded on one to six occasions from each of a group of 18 conventional calves of the Friesian breed and 29 double-muscled calves of the Belgian White and Blue breed. Ages of the calves at the times of examination ranged from eight to 348 days. The Holmes semi-orthogonal lead system was used. The waves and interval durations and the tridimensional P, QRS, and T modal vector orientation and amplitude were calculated. The magnitude of the cardiac vectors was significantly lower and the ventricular waves and QT interval duration significantly shorter in the double-muscled than in the conventional calves. The P modal vector pointed significantly less downwards and the QRS modal vector pointed significantly more forwards and less up- and rightwards in the Belgian White and Blue, than in the Friesian group. Most of the observed differences might be a consequence of the bodily, and more specifically the thoracic, conformation of the former calves. However, the lower cardiac vector magnitude and shorter wave and interval durations might also reflect lower cardiac mass in the double-muscled subjects

Bleue des prés, Porc Fleuri, Poulet d'Ardenne, trois productions de qualité différenciée en Région Wallonne

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Comparison of the cardiac pumping capability and cardiac pumping reserve in double-muscled and conventional calves.

Hereditary muscular hypertrophy is a character that has been selected in several animal species for industrial meat production. The selection of this character in cattle produces animals of exceptional commercial value but ones with a lower aerobic capacity than that of conventional cattle. The purpose of this work was to study the role of cardiac function as a potential limiting factor of aerobic capacity in double-muscled calves. Two groups of healthy calves were studied, one consisting of nine calves of conventional conformation and the other of nine double-muscled calves. Pulmonary arterial and capillary wedge, central venous, and systemic arterial pressures were measured by fluid-filled catheters and recorded together with the electrocardiogram. Cardiac output was measured by the thermodilution technique. From these measurements, the heart rate, the cardiac and the stroke indices, the pulmonary and the systemic vascular resistances, and the cardiac power output were calculated. The parameters were recorded under basal resting conditions and during incremental dobutamine challenge, which allowed determination of the resting cardiac power output, the cardiac pumping capability, and the cardiac reserve. Dobutamine challenge induced a significant rise in cardiac and stroke indices, heart rate, and cardiac power output, a significant decrease in pulmonary and systemic vascular resistances, and no change in systemic and pulmonary arterial pressures. The cardiac reserve obtained in the present study was low in comparison with those previously reported in humans, dogs, and horses. This may be related to the poor running capability of bovine species relative to that of the former species.(ABSTRACT TRUNCATED AT 250 WORDS)Comparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

Comparative assessment of right ventricular performance from the pressure-volume relationship in double-muscled and conventional calves.

Forty-one and 55 records of right-sided and systemic arterial pressures, cardiac output, and end-diastolic and end-systolic right ventricular volumes were collected from a group of 6 conventional and 6 double-muscled calves, respectively. In each group, the mean right ventricular pressure-volume loop was constructed. Global cardiac performance was significantly lower in the double-muscled than in the conventional calves. The right ventricular end-diastolic and end-systolic volumes, as well as the diastolic portion of the mean pressure-volume loop, were similar in the 2 groups. Those results suggest that the reduced cardiac performance of double-muscled calves is not due to a lowered ventricular preload and that diastolic properties of their myocardium are similar to those of conventional calves. When expressed on a body weight basis, however, the right ventricular end-diastolic and end-systolic volumes were lower in the double-muscled than in conventional calves. When expressed as a function of probable metabolic demand, therefore, the volumetric capacity of the cardiac pump appears to be reduced in double-muscled calves. The significantly lower right ventricular ejection fraction, maximal rate of ventricular pressure rise and right ventricular peak-systolic pressure to end-systolic volume ratio measured in double-muscled as compared with conventional calves suggest that reduced myocardial contractility may also be partly responsible for the significantly lower stroke index of the former calves. The cardiac pump of double-muscled cattle thus seems to be less effective than that of conventional cattle because of reduced volumetric capacity and lowered strength of contraction