Lack of microbiological contamination from bovine in vitro f ertilized embryos

Le but de cette étude était de connaître la nature et l’ampleur de la contamination éventuelle des embryons bovins fécondés in vitro à partir d’ovocytes prélevés à l’abattoir. Vingt-neuf vaches d’origine et d’âge non déterminés, à un stade quelconque de leur cycle sexuel ont été l’objet des prélèvements suivants : sang veineux périphérique (10 ml), ovocytes imma tures, liquides folliculaires et cellules d’oviducte, à des fins de recherches sérologiques (Brucellose, Leucose bovine enzootique, 1BR/1PV, BVD/MD) bactériennes ou virales (BHV 1 ; BVD/MD V). Parmi les 29 vaches, une a présenté une réaction sérologique positive vis-à-vis de la Brucellose, 2 une réaction positive vis-à-vis de la Leucose, 5 une réaction positive vis-à-vis de l’IBR/IPV et 21 une réaction positive vis-à-vis de la BVD/MD. Aucun animal n’a été trouvé virémique à la recherche du virus BVD/MD. Aucun agent bactériologique ou viral n’a été retrouvé sur les prélèvements du tractus génital, sur les œufs non segmentés ou sur les embryons. Ces observations sont compatibles avec l’absence de risques sanitaires que pourrait présenter la remise en place sur des receveuses, d’embryons fécondés in vitro issus d’ovocytes prélevés en abattoir.The aim of the present survey was to study the possible microbiological contamination of in vitro fertilized ova/embryos from oocytes collected at the abattoir. A total of 29 cows were submitted to various samplings. They were of undetermined origine, age and at any stage of their reproductive cycle. Sampling included blood from peripheral veins (10 ml), immature oocytes, follicular fluids, oviductal cells for serological (Brucellosis, Leucosis, IBR/ IPV, BVD/MD) or bacteriological or viral analysis (BHV 1; BVD/MD V). Non cleaved ova (n = 78) or embryos (n = 66) up to a maximal blastocyst stage, were obtained by total in vitro procedure. Among the 29 cows, some were serologically positive as follows: Brucellosis, 1; Leucosis, 2; IBR/IPV, 5; BVD/MD, 21. None were BVD/MD virus positive from blood samples. No bacterial nor viral contamination was found from uncleaved ova or from IVF embryos. The present observations are consistent with the possible lack of risks of contamination from IVF embryos originating from oocytes collected at the abattoir

Type-1 Cannabinoid Receptors Reduce Membrane Fluidity of Capacitated Boar Sperm by Impairing Their Activation by Bicarbonate

Background Mammalian spermatozoa acquire their full fertilizing ability (so called capacitation) within the female genital tract, where they are progressively exposed to inverse gradients of inhibiting and stimulating molecules. Methodology/Principal Findings In the present research, the effect on this process of anandamide, an endocannabinoid that can either activate or inhibit cannabinoid receptors depending on its concentration, and bicarbonate, an oviductal activatory molecule, was assessed, in order to study the role exerted by the type 1 cannabinoid receptor (CB1R) in the process of lipid membrane remodeling crucial to complete capacitation. To this aim, boar sperm were incubated in vitro under capacitating conditions (stimulated by bicarbonate) in the presence or in the absence of methanandamide (Met-AEA), a non-hydrolysable analogue of anandamide. The CB1R involvement was studied by using the specific inhibitor (SR141716) or mimicking its activation by adding a permeable cAMP analogue (8Br-cAMP). By an immunocytochemistry approach it was shown that the Met-AEA inhibits the bicarbonate-dependent translocation of CB1R from the post-equatorial to equatorial region of sperm head. In addition it was found that Met-AEA is able to prevent the bicarbonate-induced increase in membrane disorder and the cholesterol extraction, both preliminary to capacitation, acting through a CB1R-cAMP mediated pathway, as indicated by MC540 and filipin staining, EPR spectroscopy and biochemical analysis on whole membranes (CB1R activity) and on membrane enriched fraction (C/P content and anisotropy). Conclusions/Significance Altogether, these data demonstrate that the endocannabinoid system strongly inhibits the process of sperm capacitation, acting as membrane stabilizing agent, thus increasing the basic knowledge on capacitation-related signaling and potentially opening new perspectives in diagnostics and therapeutics of male infertility

Evaluation of bull semen fertility by homologous in vitro fertilization tests

International audienc

In vitro culture of bovine egg fertilized either in vivo or in vitro

International audienc