Atypical localisation of spinal compression caused by a sporadic lymphosarcoma in a calf

Poster (2006, October 16)

Endocrinology of pregnancy in the cow: embryonic signals, placental hormones and proteins

in Annales de Médecine Vétérinaire (2006), 150(4), 212-226

The development, the establishment and the embryonic survival at early stages of gestation are depending on an intimate dialogue between the embryo and his mother. For the embryo part, it is especially ... [more ▼]

The development, the establishment and the embryonic survival at early stages of gestation are depending on an intimate dialogue between the embryo and his mother. For the embryo part, it is especially the trophoblast, or the future placenta, which plays a key role in initializing pregnancy. The placenta emits many signals of various chemical natures ( steroids, prostaglandins, peptides, proteins), some of them, e. g. the interferon tau, determine the maintenance of the corpus luteum at the beginning of gestation. Until now, although having raised many speculations, the earliest of these signals were not identified in peripheral circulation. Consequently, they cannot be used as a pregnancy diagnosis or to indicate embryonic mortality. However, since the eighties, the specific proteins "associated with pregnancy", produced by the trophoblastic cells are used as tool for breeding management. Most of these molecules are present in peripheral circulation. In this review, we will describe the major mechanisms associated with the maternal recognition of the gestation and their possible applications as pregnancy diagnosis tool in the cow. [less ▲]

Emergence of bovine Ehrlichiosis in Belgium

Conference (2005)

Investigation on prenatal endocrinology: preliminary results on long term catheterisation of bovine foetuses

in Reproduction (Cambridge, England). Abstract Series (2004), 31

La parésie spastique du quadriceps fémoral : Une nouvelle entité clinique chez le veau de race Blanc Bleu Belge.

in Annales de Médecine Vétérinaire (2003), 147

Viability of cloned bovine embryos after one or two cycles of nuclear transfer and in vitro culture

in Theriogenology (1995), 44

We described an exclusively in vitro procedure for cloning and recloning bovine embryos. Embryos obtained by IVM/IVF/IVC developed to the morula stage were used as blastomere donors in cunjunction with ... [more ▼]

We described an exclusively in vitro procedure for cloning and recloning bovine embryos. Embryos obtained by IVM/IVF/IVC developed to the morula stage were used as blastomere donors in cunjunction with IVM recipient oocytes. Reconstructed embryos were developed in vitro in co-culture using bovine oviductal epithelial cells. The resulting morulae were used as donors for recloning under the same experimental conditions. No significant difference was observed between cloning and recloning in terms of development (rates of blastocysts: 12.9 versus 14.9%), in the number of nuclei per blastocyst (63.8 versus 49.1), or in pregnancy rates (35.7 versus 33.3%). The high variability observed between replicates and the correlation between results in first and second cycle nuclear transfer may suggest an inherant potential of individual donor embryos to support development by cloning [less ▲]

Clonage par greffe de blastomère: naissance d'un premier veau

in Annales de Médecine Vétérinaire (1993), 137(8), 573-574

Comparison between culture of bovine embryos in vitro versus development in rabbit oviducts and in vivo

in Livestock Production Science (1993), 36

The aim of this work was to evaluate the efficiency of different embryo culture methods for in vitro embryo production: development in co-culture with bovine oviductal epithelial cells (BOEC), in BOEC ... [more ▼]

The aim of this work was to evaluate the efficiency of different embryo culture methods for in vitro embryo production: development in co-culture with bovine oviductal epithelial cells (BOEC), in BOEC conditioned medium (CM) or in rabbit oviducts, versus in vivo produced embryos. There was no significant difference in terms of percentages of cleaved and 8-cell stages obtained between CM and BOEC. In CM, 24.8% of the cleaved embryos became blastocysts. In BOEC, 14.5% of the cleaved embryos became blastocysts. Among the 190 zygotes transferred in the rabbit oviducts, 127 have been recovered 5 days later, and 17.4% became blastocysts. There was no significant difference in term of blastocyst formation between the development in rabbit and in BOEC. However, there was a significant difference between the CM group and the two other groups. The numbers of cells in blastocysts from different sources were investigated: in vivo blastocysts contained 107 cells assumed to be 100%, in vitro blastocysts developed in rabbit oviduct 100.1 cells (93.3%), BOEC blastocysts 90.8 cells (84.6%) and CM blastocysts 72.3 cells (67.3%). This study confirmed earlier works on the oviduct effect on blastocyst quality in terms of development rate and cell number. [less ▲]

Multiplication des embryons chez les bovins: possibilités actuelles et futures

in Biotechnologie en Sélection animale - IRSIA (1989)

Since several years, research efforts have been focused towards improving the reproductive potential of domestic animals. The authors present a review of different technics in particular the ... [more ▼]

Since several years, research efforts have been focused towards improving the reproductive potential of domestic animals. The authors present a review of different technics in particular the superovulation and priming, embryo micromanipulation and clonage. The technic of superovulation allows an increase of the total number fo the offspring by an increase of the ovocytes total number. Different FSH injections at the end of the cycle, preceded by small FSH quantity at the beginning of the cycle, procure a great number of mature follicles available for reproduction. Micromanipulation allows a multiplicaton by sectioning the embryo in two or more segments. Isolated blastmeres can also be used but it was observed that those cells very rapidly loose their differentiation potential. Clonage allows the reproduction of an animal from only one of his own cells. The nucleus of this cell is extracted and reimplanted in an enucleated ovocyte. Meanwhile from a practical point of vue, this technic is, at present, only possible using a stem cell and not using a mature somatic cell. [less ▲]

Maturation et fécondation in vitro chez les bovins: naissance d'un veau

in Annales de Médecine Vétérinaire (1989), 133