Aim:The study was conducted to determine seroprevalence of the five diseases influenza, Newcastle, Mycoplasma gallisepticum, Mycoplasma synoviae and salmonella, among around native hens of Eghlid in Iran, on spring 2011. Materials and Methods:On the basis of native Hens distribution, this region divided into four parts of Eghlid, Doskord, Sedeh and Hasan-abad. Fifty unvaccinated native Hens randomly selected from each part. Blood samples were aseptically collected from the wing veins using 5-ml sterile syringe. Serum from hens was tested for detection and titration for Mycoplasma and Salmonella by the rapid slide agglutination method, and was tested for influenza and Newcastle by the Hemagglutination Inhibition Assay. The data was analyzed completely in randomized design with four treatments, 50 repetitions for each disease. Conclusion:Contamination of Influenza, Newcastle and Mycoplasma gallisepticum was high, and the highest contamination rate was related to Mycoplasma gallisepticum. It is usually recommended that preventive strategies, such as appropriate husbandry and hygiene, sanitary handling of chicks and eggs, routine health monitoring and vaccination of Native hens should be emphasized.

Summary MicroRNAs (miRNAs) are small non-encoding RNAs that actively regulate biological and physiological processes, and play an important role in regulating gene expression in all cells, especially in most animal cells, including oocytes and embryos. The expression of miRNAs at the right time and place is crucial for the oocyte’s maturation and the embryo’s subsequent development. Although assisted reproductive techniques (ART) have helped to solve many infertility problems, they cause changes in the expression of miRNA and genes in oocytes and preimplantation embryos, and the effect of these changes on the future of offspring is unknown, and has caused concerns. The relevant genomic alterations commonly imposed on embryos during cryopreservation may have potential epigenetic risks. Understanding the biological functions of miRNAs in frozen maturated oocytes may provide a better understanding of embryonic development and a comparison of fertility conservation in female mammals. With the development of new techniques for genomic evaluation of preimplantation embryos, it has been possible to better understand the effects of ART. The results of various articles have shown that freezing of oocytes and the cryopreservation method are effective for the expression of miRNAs and, in some cases, cause changes in the expression of miRNAs and epigenetic changes in the resulting embryo. This literature review study aimed to investigate the effects of oocyte cryopreservation in both pre-maturation and post-maturation stages, the cryopreservation method and the type of cryoprotectants (CPA) used on the expression of some epigenetic-related genes and miRNAs.

Apart from oocyte quality, the media used has a significant effect on the production and quality of blastocysts produced in vitro. This study was designed to evaluate the replacement of serum with human amniotic membrane stem cells’ conditioned medium (hAMSCs‐CM) during bovine embryo culture on the quantity and quality of produced blastocysts. The in‐vitro‐produced embryos on the third day of IVC were randomly divided into the following culture groups: SOFaa + 5% FBS (Control), SOFaa + 5% hAMSCs‐CM (5% CM), SOFaa + 2.5% hAMSCs‐CM + 2.5% FBS (2.5% CM) and SOFaa + hAMSC co‐culture (co‐culture). The blastocyst and hatching rates, blastocyst cells number (the number of trophectoderm, inner cell mass and total cells), and the expression of some developmentally important genes (OCT4, PLAC8 and COX2 genes) in the treated groups, especially in the 5% CM, compared to the control had improved (p < .05). No significant difference was observed between groups for viability and hatching rate in vitrified‐warmed blastocysts. Due to the positive effect of hAMSCs’ conditioned medium (hAMSCs‐CM) on blastocyst production, as well as its ease of preparation and the need to avoid the transmission of microbial contamination to the culture medium, hAMSCs‐CM can be used as a suitable alternative to FBS during 3 to 8 days of bovine embryo culture.