Effect of milking frequency on oxytocin release and milk production in dairy ewes.

The experiment was conducted to investigate the effectiveness of milking stimulus on oxytocin release and to compare the effect of milking frequency on plasma levels of oxytocin and milk parameters. Twelve Lacaune ewes were subjected to six treatments (T1, T2, T3, T4, T5 and T7 daily milkings) during 6 days. At each milking, blood was sampled and plasma oxytocin levels were determined by enzyme immunoassay.

[First case of multiforme granuloma in Congo].

We report a case of multiform granuloma observed in a young woman of 28 years from Brazzaville, Congo. Extended lesions on the arms, back, face, legs and feet appeared over one month. They consisted of slightly squamous erythemato-oedematous plaques, with polycyclical margins and raised papular borders.

Intramammary pressure and luteal oxytocin after PGF2 alpha administration in cycling and early pregnant ewes.

The aim of this work was to investigate whether luteal oxytocin released after non-luteolytic prostaglandin F2 alpha (PGF2 alpha) challenge could explain the intramammary pressure (IMP) rises previously described in pregnant ewes after the normal life span of a corpus luteum. Blood oxytocin levels and IMP after challenge were measured in cycling and pregnant lactating ewes until the response ceased (approximately 55 d post oestrus). Oxytocin release was not significantly different for cycling and pregnant ewes, and fell to its lowest levels on days 16-18 post oestrus in both groups, i.

[Influence of the number of corpora lutea on the release of luteal oxytocin, the transfer of alveolar milk to the cistern and milk production in the ewe].

This experiment was conducted in 59 Lacaune breed ewes in order to compare milk production and milk distribution between alveolar and cisternal storage after superovulation. After a corpora lutea (CL)-free control period, the ewes were superovulated by different treatments (experimental period) and 5 classes were differentiated according to the number of corpora lutea observed (0, 1, 2, 3 to 6 and > 6 CL respectively (group A (n = 20), B (n = 7), C (n = 14), D (n = 7), E (n = 11)). Our results showed a positive correlation between the number of corpora lutea and the oxytocin and progesterone levels in plasma, total milk production and cisternal volume, and a negative correlation with alveolar volume.

[Early diagnosis of pregnancy in the cow as assessed by milk ejection induced by luteal oxytocin].

The diagnosis of pregnancy described in this article is based on the observation of milk ejection which, in the case of corpus luteum maintenance, results from the release of luteal oxytocin induced by intravenous administration of a non luteolytic dose of PGF2 alpha. The tests were performed in 410 lactating cows, 18-22 days after insemination (mean 19.95 days, SD 0.