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Öğe Application of reproductive biotechnologies for sustainable production of livestock in Turkey(SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK, 2018) Kaya, Abdullah; Gunes, Erdogan; Memili, ErdoganReproductive biotechnology encompasses powerful tools to enhance the efficiency and profitability of livestock reproduction, production, and product quality. These technologies include genomic selection, evaluation of semen (from bulls, bucks, and rams) using advanced cell and molecular technologies, semen cryopreservation and artificial insemination, estrus synchronization, superovulation of the females (cows, dams, and ewes), ovum pick-up, in vitro fertilization and embryo culture, embryo transfer, and pregnancy detection. The extent of applications of these modern technologies and their economic impacts for livestock production in Turkey are elusive. As a result, there is an urgent need for sound economic analyses, research and education, training of animal producers to facilitate technology transfer, and informing of the public of the benefits of animal biotechnology. The objective of this study was to provide a review of key reproductive technologies and economic analyses of them, followed by an outlook on the future production of cattle, goats, and sheep in Turkey. This review is an important resource for students, researchers, and producers for a better understanding and for the application of cutting-edge biotechnology in efficient, sustainable, and profitable livestock production.Öğe Leptin and IGF-I improve bovine embryo quality in vitro(BRAZILIAN COLL ANIMAL REPRODUCTION, 2017) Kaya, Abdullah; Sagirkaya, Hakan; Misirlioglu, Muge; Gumen, Ahmet; Parrish, John J.; Memili, ErdoganThe in vitro embryo culture systems need further improvement to enhance the efficiency of bovine embryo production. Growth factors play key roles in embryo production and quality. The objective of this study was to define the effects of leptin, insulin-like growth factor-1 (IGF-1), and their combination on embryonic development, apoptosis, and expression profiles of a panel of developmentally important genes during 8-day embryo culture. The oocytes were aspirated from slaughterhouse ovaries of mixed breed cows. Following IVM/IVF presumptive zygotes were obtained. To accomplish this objective, presumptive zygotes (16-18 h post-insemination) were cultured in vitro as control (no supplementation, n = 349), 5 ng/ml leptin (Group I, n = 322), 100 ng/ml IGF-1 (Group II, n = 347), and 5 ng/ml leptin and 100 ng/ml IGF-1 (Group III, n = 360). All groups were supplemented with 10% fetal calf serum (FCS) on Day 4, and blastocysts were harvested on day 8. The DNA-fragmented nuclei of blastocyst were determined by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and expression profiles of a panel of developmentally important genes were assayed by real-time polymerase chain reaction (RT-PCR). The cleavage rate and embryo development to 8-16 cell stage were higher in groups II and III as compared to control (P < 0.05), respectively. Percentage of blastocyst and mean cell numbers per blastocyst did not differ among the groups. Addition of IGF-I and/or combination with leptin decreased the number of nuclei with fragmented DNA (P < 0.01) as compared to the control group. Although the expression of glucose transporter 1 (Glut1), desmosomal glycoprotein desmocollin III (DcIII), and insulin like growth factor 2 receptor (Igf2r) transcripts did not change among the groups, interferon-tau (IF-tau) and DNA methyltransferase 3A (Dnmt3a) were down-regulated in group II while heat shock protein-70 (Hsp70) and IF-tau were up regulated in group III. Results indicate that addition of IGF-I in culture media improved the cleavage rate; combination with leptin also improved the development rates to 8-16-cell-stage embryos, decreased the TUNEL-positive nuclei, and caused alterations in the amounts of transcripts for the developmentally important genes assayed.Öğe Metabolomic markers of fertility in bull seminal plasma(PUBLIC LIBRARY SCIENCE, 2018) Velho, Ana Luiza Cazaux; Menezes, Erika; Thu Dinh; Kaya, Abdullah; Topper, Einko; Moura, Arlindo Alencar; Memili, ErdoganMetabolites play essential roles in biological systems, but detailed identities and significance of the seminal plasma metabolome related to bull fertility are still unknown. The objectives of this study were to determine the comprehensive metabolome of seminal plasma from Holstein bulls and to ascertain the potential of metabolites as biomarkers of bull fertility. The seminal plasma metabolome from 16 Holstein bulls with two fertility rates were determined by gas chromatography-mass spectrometry (GC-MS). Multivariate and univariate analyses of the data were performed, and the pathways associated with the seminal plasma metabolome were identified using bioinformatics approaches. Sixty-three metabolites were identified in the seminal plasma of all bulls. Fructose was the most abundant metabolite in the seminal fluid, followed for citric acid, lactic acid, urea and phosphoric acid. Androstenedione, 4-ketoglucose, D-xylofuranose, 2-oxoglutaric acid and erythronic acid represented the least predominant metabolites. Partial-Least Squares Discriminant Analysis (PLSDA) revealed a distinct separation between high and low fertility bulls. The metabolites with the greatest Variable Importance in Projection score (VIP > 2) were 2-oxoglutaric acid and fructose. Heat-map analysis, based on VIP score, and univariate analysis indicated that 2-oxoglutaric acid was less (P = 0.02); whereas fructose was greater (P = 0.02) in high fertility than in low fertility bulls. The current study is the first to describe the metabolome of bull seminal plasma using GC-MS and presented metabolites such as 2-oxoglutaric acid and fructose as potential biomarkers of bull fertility.Öğe Retained acetylated histone four in bull sperm associated with fertility(FRONTIERS MEDIA SA, 2019) Ugur, Muhammet Rasit; Kutchy, Naseer Ahmad; de Menezes, Erika Bezerra; Ul-Husna, Asma; Haynes, Bethany Peyton; Uzun, Alper; Kaya, Abdullah; Topper, Einko; Moura, Arlindo; Memili, ErdoganBull fertility, ability of the sperm to fertilize and activate the egg and support embryo development, is vital for cattle reproduction and production. Even though majority of histories are replaced by protamines, some histories are retained in sperm. It is known that chromatin remodeling during spermatogenesis results in dynamic changes in sperm chromatin structure through post-translational modifications (PTM) of sperm histones, which are important for regulation of gene expression. However, amounts of sperm Histone 4 (H4), its acetylated form (H4 acetyl), and to what extent these molecular attributes influence sperm chromatin structure and bull fertility are unknown. These gaps in the knowledge base are important because they are preventing advances in the fundamental science of bovine male gamete and improvement of bull fertility. The objective of this study was to test the hypothesis that expression dynamics as well as PTM of sperm H4 are associated with bull fertility. Flow cytometry was utilized to quantify H4 and H4 acetylated form in sperm from seven high and seven low fertility Holstein bulls. The results indicated that the average number of cells with H4 or H4 acetyl expression in high and low fertility bull sperm were 34.6 +/- 20.4, 1.88 +/- 1.8, 15.2 +/- 20.8, and 1.4 +/- 1.2, respectively. However, the sperm enriched in both H4 and H4 acetyl were different between high and low fertility groups (3.5 +/- 0.6; 1.8 +/- 0.8; P = 0.043). The localization and detection of H4 and H4 acetylation were measured by immunocytochemistry which revealed that H4 and H4 acetylation were equally distributed in the sperm head of high and low fertility sires. Western blotting results confirmed the presence of the H4 and its acetylated form in the sperm. Bioinformatics studies demonstrated that H4 is highly conserved among mammalians, and have significant gene ontology on spermatogenesis, early embryo implantation, and sperm capacitation. The results are significant because it demonstrates the replacement of canonical histone H4 into modified H4 acetylation in sperm and regulate its dynamics which is crucial for bull fertility and reproductive biotechnology. These findings advance fundamental science of mammalian early development and reproductive biotechnology.Öğe Sperm macromolecules associated with bull fertility(ELSEVIER, 2016) Kaya, Abdullah; Memili, ErdoganBull fertility, ability of the sperm to fertilize and activate the egg that sustain embryo development, is vitally important for effective and efficient production of cattle. Fertility is a complex trait with low heritability. Despite recent advances in genomic selection and possibility of enormous paternal benefits to profitable cattle production, there exist no reliable tests for evaluating semen quality and predicting bull fertility. This review focuses on sperm macromolecules such as transcripts, proteins and the epigenome, i.e.,the functional genome that are associated with bull fertility. Generating new information in these systems is important beyond agriculture because such progress advances the fundamental science of the mammalian male gamete while at the same time introduces biotechnology into livestock production. Sperm macromolecules and epigenome markers associated with bull fertility can be used alone or in combination with the current SNP microarrays to determine sperm quality and to indicate bull fertility. (C) 2016 Elsevier B.V. All rights reserved.
