2001 - 70 (6)

In 1996 and 1997 a new epizootic enteric rabbit disease appeared in Europe. Since then the disease has also been reported in other parts of the world. Its main symptoms are caused by paresis of the intestinal tract. The causative agent is still unknown. The disease has been reported in meat rabbits and does, as well as in pet rabbits. The present report concerns a naturally occurring case of this disease in a specific-pathogen-free (SPF) rabbit colony. In the intestinal contents of one animal sacrificed for thorough examination, rotavirus and an apathogenic type of Escherichia coli were detected. From the ileal wall Providencia rettgeri was isolated, which is unlikely, however, to be of pathogenic significance. Histological and electron-microscopical analyses did not reveal any pathognomonic lesions.

This case report discusses the perinatal death of a Belgian Blue and White calf due to an intra-abdominal haemorrhage after parturition. It was caused by persistent bleeding of the umbilical arteries. These arteries were retracted but did not show any constriction. Keywords: Calf - Perinatal Death - Umbilicus - Arteria Umbilicalis

In this study, the effect of the insemination dose (250 or 500 x 106 fresh spermatozoa) on pregnancy rate at 35 days post-insemination (PI) in synchronized ewes was analyzed. The 30 days non-return rate was determined by the introduction of an intact ram harnessed with a crayon at 10 days PI. At 35 ± 2 days PI, the ewes were scanned for pregnancy by means of transrectal ultrasonography (7 MHz). Five months PI, the lambing rate and fecundity were recorded. No significant differences (p<0.05) were found in non-return rate, pregnancy or fecundity between 250 and 500 x 106 fresh spermatozoa per insemination dose. Increasing the number of spermatozoa from 250 x 106 to 500 x 106 per insemination dose did however improve the lambing rate (p<0.1). Pregnancy control by transrectal ultrasound (7 MHz) at 35 ± 2 days was at least as reliable as a teaser ram.