Equine Embryo Sexing and Ultrasonographic Foetal Sexing - Interests and Applicability.

The ability to choose the sex of the offspring is of upmost economic importance for horse breeders. Unlike other species, horses present several reproductive peculiarities that interfere with assisted reproductive technologies used in other large animals (such as bovine) and make them difficult to apply. Thus, there is a great interest to determine the sex of the offspring as soon as possible. This has led to the development of several technologies to serve this purpose, which can be classified into two categories. One is equine embryo sexing by either non-invasive biotechnological methods, such as monitoring of X-linked enzymes before X chromosome inactivation and detection of sex-specific antigen, or by invasive biotechnological methods, such as cytogenetic analysis and polymerase chain reaction (PCR). The other one is equine foetus sexing using ultrasound scanning in different stages of its development (early, mid or late), by different approaches (transrectally or transabdominally). This can be performed with classic B-mode ultrasound machines or using 3D-mode and Doppler-mode scanners. This review article offers a comprehensive overview of the current status of these procedures as well as an assessment of their interests and applicability.

Evaluation of bovine embryo biopsy techniques according to their ability to preserve embryo viability.

The purpose of this research was to evaluate three embryo biopsy techniques used for preimplantation genetic diagnosis (PGD) in cattle and to recommend the least invasive one for current use, especially when PGD is followed by embryo cryopreservation. Three hundred bovine embryos were biopsied by either one of the needle, aspiration or microblade method, and then checked for viability by freezing/thawing and transplantation to recipient cows. The number of pregnancies obtained after the transfer of biopsied frozen/thawed embryos was assessed 30 days later using ultrasounds. The results were significantly different between the three biopsy methods: the pregnancy rate was of 57% in cows that received embryos biopsied by needle, 43% in cows that received embryos biopsied by aspiration, and 31% in cows that received embryos biopsied by microblade. Choosing an adequate biopsy method is therefore of great importance in embryos that will undergo subsequent cryopreservation, as it significantly influences their viability after thawing.

Establishment of an embryonic stem cell line from blastocyst stage mouse embryos.

Embryonic stem cells have the ability to remain undifferentiated and proliferate in vitro while maintaining the potential to differentiate into derivatives of all three embryonic germ layers. The aim of the present study was to establish mouse ES lines from blastocyst stage embryos obtained after CD1/EGFP mice superovulation. We isolated, cultured and determined the characteristics of mouse embryonic stem cells in early passages, which were first described by Evans M and Kaufman M. Therefore, we evaluated the morphological criteria for the approval of ES cells in early expansion stage. Two cell lines were isolated (CDE1 and CDE2) and analyzed. They showed similar characteristics to those reported earlier for blastocyst-derived ES cell lines.

The influence of hexestrol diacetate on gametogene function in male rabbit.

The research was performed on 24 male sexually mature domestic rabbits, divided in two equal batches. The rabbits from the first batch were administered 0.5 mg/kg of body weight hexestrol diacetate intramuscularly twice a week for four consecutive weeks. Batch 2 was used for control. The testicular tissue samples obtained after orchidectomy were processed in order to obtain histological samples, stained using the Goldner's trichrome method. Examination of histological sections from the control batch showed that a natural aspect of seminal tubule epithelium, without reported injuries, even discrete. In the experimental batch were recorded a number of changes to all categories of the seminal cells. The severity and extent of damages varied greatly from one seminal tube to another and even from one part to another of the same seminal tube. These changes were the appearance of apoptotic cells and apoptotic bodies, vacuolar degenerescence of spermatocytes and spermatides, syncitialisation of spermatides, areas of necrosis accompanied by severe disruption of the seminiferous epithelium. In some areas, the lesions were so severe that the affected area of the cells forms "basal area". If lesions in the "adluminal area" affects only temporarily gametogenetic function the lesions in the "basal area" are irreversible as there are named "reserve cells" which is the starting point of spermatogenesis. Highlighted issue raised on the opportunity use of hexestrol diacetate in therapy or animal production stimulation as it gametogenetic function in males while their risk transfer to humans through consumption of foods of animal origin.

[A method for the treatment of oviduct obstruction in cattle using CO2 insufflation into the uterus]. / Eine Methode zur Behandlung von Eileiterobstruktionen beim Rind durch CO2-Insufflation in den Uterus.

The investigations were carried out on 59 cows from Holstein half-breed, establishing that 8 cows suffered salpinx obstruction (5 cases with unilateral obstruction and 3 cases with bilateral obstruction). The authors are using an apparatus made by themselves, for insufflation of air in the obstructed uterus, and which is useful in desobstruction treatment, too. For diagnosis, CO2 was introduced inside of uterus. The authors used for treatment PBS (saline phosphate buffer) in addition with penicillin G, hydrocortisone and trypsin. Before air insufflation in uterus there will be infused 10-20 ml 2% Lidocaton. The cows must be examined in oestrus period, or 2 days after PGF2 alfa administration. The gas must be introduced under rectal palpation, and pressure must not be higher than 500 mm H2O column. If there is a permeable oviduct, after 15-20 sec. from gas introduction, ist is possible to palpate the filled oviduct. From ovary we can perceive a rustle produced by gas crossing in abdominal cavity. In case of salpinx obstruction, the treatment must be start as soon as possible. The utilized liquid for treatment will be introduce by gas pressure, inside of uterus and oviducts. Using this method, it managed the repermeability of oviducts at 3 from 8 treated cows. In each case, there were used 3 treatments at 48 h interval. After the second insemination (I.A.) 2 cows remained pregnant.