Risk Factor Analysis and Genetic Parameter Estimation for Pre-Weaning Mortality Traits in Boer, Spanish, and Crossbred Goat Kids

The objectives of this study were to evaluate fixed risk factors associated with PWM and to estimate genetic parameters for PWM. A total of 927 birth records from a mixed population of purebred and crossbred Boer and Spanish goats born between 2016 and 2023 at the International Goat Research Center (IGRC) were used for this study. Four binary traits were studied: D0-3 (death within 3 days after birth), D4-60 (death between 4 and 60 days), D61-90 (death between 61 and 90 days), and D0-90 (death within 90 days). Logistic regression models were used to evaluate the risk factors associated with PWM traits. Bayesian threshold models and Gibbs sampling were used to estimate the genetic parameters. Birth weight, season, litter size, sex, dam age, breed, and heterosis were found to be significantly associated with at least one of the PWM traits. Heritability estimates were 0.263, 0.124, 0.080, and 0.207, for D0-3, D4-60, D61-90, and D0-90, respectively. The genetic correlations between the studied traits ranged from 0.892 (D0-3 and D0-90) to 0.999 (D0-3 and D61-90). These results suggest that PWM in goats is influenced by both non-genetic and genetic factors and can be reduced by management, genetic selection, and crossbreeding approaches.

Altered luteal expression patterns of genomic and non-genomic progesterone receptors in bitches at different reproductive states

The binding of steroid hormones to their specific receptors is necessary to exert their effects on target cells. Progesterone (P4), a steroid hormone, carries out its effects through both genomic and non-genomic (the cell membrane-associated) receptors. This study aimed to ascertain luteal expression patterns of genomic and non-genomic progesterone receptors in bitches in physiological (early dioestrus and early pregnant) and pathological (pyometra) reproductive states. Luteal tissue was collected from the bitches at early dioestrus (ED, n = 5), early pregnant (EP, n = 5), and pyometra (PY, n = 5). The expression profiles of Steroidogenic Acute Regulator Protein (STAR), Progesterone Receptor (PGR), Membrane Progestin Receptors (PAQR5, PAQR7 and PAQR8), and Progesterone Membrane Components (PGMRC1 and PGMRC2) were examined at the mRNA levels using Real-Time Polymerase Chain Reaction (RT-PCR). Protein levels of PGR, PGMRC1 and PGMRC2 were detected by western blotting (WB). The STAR expression was found in all groups, with a statistical difference observed between EP and PY groups (P < 0.05). The protein level of PGR was determined to be highest in the EP group and lowest in the PY group. The expression of PAQR8 increased in the EP group (P < 0.05). The PAQR5 exhibited high expression in the EP group and low expression in the PY group (P < 0.05). PGRMC1 was more elevated in the EP group and lower in the PY group (P < 0.05). Protein levels of PGMRC1 and PGMRC2 were also observed at the highest expression in EP group. According to the altered expression profiles for examined receptors, we suggest that those progesterone receptors have roles in early pregnancy or pyometra in bitches.

Expression of circulating oar-miR-485-5p and oar-miR-493-5p during the estrous cycle and early pregnancy in ovine plasma

In the current study, we aimed to assess the expression levels of two circulating microRNAs (miRNA) (oar-miR-485-5p and oar-miR-493-5p) in the ovine plasma during the peri-implantation. After mating, we collected the plasma samples from a total of 8 ewes on day 22 of pregnancy (P22; n = 4) and day 22 of the estrous cycle (C22; n=4). We used mature miRNA sequences for oar-miR-485-5p and oar-miR-493-5p out of one hundred fifty, which were retrieved from our microarray results of previous study. We showed that the miRNA expression of oar-miR-485-5p and oar-miR-493-5p were upregulated in P22 (P<0.05) when compared to C22. Those two miRNAs targeted 311 target genes in the peri-implantation period of pregnancy. Furthermore, we revealed 151 GO/pathway terms in biological process (BP) and 25 GO/pathway terms in molecular function (MF), while we demonstrated 13 GO/pathway terms in cellular component (CC). We revealed three hub genes as interleukin 2 (IL2), interleukin 18 (IL18), and C-X-C Motif Chemokine Ligand 10 (CXCL10). In conclusion, both miR-485-5p and oar-miR-493-5p have the potential to be a biomarker to understand peri-implantation of the ovine pregnancy in the aspect of pregnancy-reflected changes in maternal plasma.

Effects of essential oil mixtures on expression of genes involved in lipogenesis and fatty acid oxidation in geese (Anser anser)

The use of essential oils has recently increased in the poultry sector. The aim of this study was to investigate the effects of essential oil mixture (juniper, mint, oregano and rosemary oil) on fatty acid oxidation and lipogenic gene expression in geese. Research groups were formed as C (control; no additives), EK1 (0.4 ml/l essential oil mixture supplemented) and EK2 (0.8 ml/l essential oil mixture supplemented). Relative expression levels of genes included in lipogenesis (ACCα, ChREBP, FASN, LXRα and SREBP-1) expression levels of genes included in fatty acid oxidation (ACOX1, CPT1, CPT1A, PPARα and PPARγ) were measured using RT-qPCR. Group EK1 upregulates the mRNA expression levels of genes involved in lipogenesis such as ACCα, ChREBP and SREBP-1, while it downregulates the mRNA expression in levels of all genes involved in fatty acid oxidation. Group EK2 increases the mRNA expression levels of genes involved in lipogenesis such as ACCα, FASN and SREBP-1, while it decreased mRNA expression at the levels of all genes involved in fatty acid oxidation, as in the other group. In the study, adding an essential oil mixture to drinking water is predicted to increase fatty liver because it upregulates genes related to fat synthesis (lipogenesis) and downregulates genes related to fat degradation (fatty acid oxidation).

Metabolomics characteristics associated with milk yield and milk quality in sheep

Standart süt testleri, süt verimi ve kalitesi gibi izleme özelliklerini içerir. Standart süt testlerinin yapılmasına ek olarak, süt özelliklerini belirlemek için potansiyel biyobelirteçler olarak hareket edebilecek metabolitleri değerlendirmek artık mümkün. Bu çalışma İvesi koyunlarında süt verimi ve kalitesi ile ilgili metabolomik parametreleri belirlemek amacıyla yapılmıştır. Çalışmamızda süt verimi yüksek 13, süt verimi düşük 13 olmak üzere toplam 26 İvesi koyunu incelenmiştir. Metabolomik analiz için sıvı kromatografi tandem kütle spektrometrisi kullanıldı. Aspartik asit, ornitin, anserin ve sistatiyonin düzeyleri açısından iki grup arasında farklı düzeylerde istatistiksel olarak anlamlı fark vardı (P<0.05 ve P<0.01). Süt verimi ile aspartik asit (r=-0,630) ve anserin (r=-0. 522) seviyeleri (P<0.01). Laktoz seviyeleri ile lizin (r=−0.501), alfa-aminoadipik asit (r=−0.524) ve hidroksilizin (r=−0.511) seviyeleri arasında anlamlı bir negatif korelasyon bulundu (P<0.01). Somatik hücre sayısı ve alanin (r=0,493), aspartik asit (r=0,418), prolin (r=0,421), alfa-aminoadipik asit (r=0,407), beta-alanin (r=0,433) ve tiyaprolin (r =0.434) seviyeleri (P<0.05) pozitif korelasyon gösterdi. Sonuçlarımız, koyun sütü verimi ve süt kalitesiyle ilgili metabolik olaylar hakkında, süt üretimini iyileştirmek ve koyun sütünün bileşenlerini geliştirmek için daha ileri araştırmalara rehberlik edebilecek önemli bilgiler sağlar. Somatik hücre sayısı ve alanin (r=0,493), aspartik asit (r=0,418), prolin (r=0,421), alfa-aminoadipik asit (r=0,407), beta-alanin (r=0,433) ve tiyaprolin (r =0.434) seviyeleri (P<0.05) pozitif korelasyon gösterdi. Sonuçlarımız, koyun sütü verimi ve süt kalitesiyle ilgili metabolik olaylar hakkında, süt üretimini iyileştirmek ve koyun sütünün bileşenlerini geliştirmek için daha ileri araştırmalara rehberlik edebilecek önemli bilgiler sağlar. Somatik hücre sayısı ve alanin (r=0,493), aspartik asit (r=0,418), prolin (r=0,421), alfa-aminoadipik asit (r=0,407), beta-alanin (r=0,433) ve tiyaprolin (r =0.434) seviyeleri (P<0.05) pozitif korelasyon gösterdi. Sonuçlarımız, koyun sütü verimi ve süt kalitesiyle ilgili metabolik olaylar hakkında, süt üretimini iyileştirmek ve koyun sütünün bileşenlerini geliştirmek için daha ileri araştırmalara rehberlik edebilecek önemli bilgiler sağlar.

Circulating miRNAs in maternal plasma as potential biomarkers of early pregnancy in sheep

MicroRNA (miRNA) plays an important role in the control of gene expression and is implied in many biological functions, including embryo implantation and development. The aim was to assess plasma miRNA profiles during the peri-implantation and ascertain potential candidate miRNA markers for early pregnancy diagnosis in ovine plasma. The plasma samples were obtained from a total of 24 ewes on days 12 (pre-implantation; P12, n = 4), 16 (implantation; P16, n = 4) and 22 (post-implantation; P22, n = 4) after mating, and on their corresponding days of 12 (Pre-C; C12, n = 4), 16 (Imp-C; C16, n = 4) and 22 (Post-C; C22, n = 4) of the estrous cycle. The miRNA profiles in plasma were assessed by microarray technology. We detected the presence of 60 ovine-specific miRNAs in plasma samples. Of these miRNAs, 22 demonstrated a differential expression pattern, especially between the estrous cycle and early pregnancy, and targeted 521 genes. Two miRNAs (oar-miR-218a and oar-miR-1185-3p) were confirmed using RT-qPCR in the ovine plasma samples. Protein-protein interaction (PPI) network of target genes established six functional modules, of which modules 1 and 3 were enriched in the common GO terms, such as inflammatory response, defense response, and regulation of immune response. In contrast, module 2 was enriched in the developmental process involved in reproduction, embryo development, embryonic morphogenesis, and regulation of the developmental process. The results indicate that miRNAs profiles of plasma seemed to be modulated during the peri-implantation stage of pregnancy in ewes. Circulating miRNAs could be promising candidates for diagnosis in early ovine pregnancy.

Expression pattern and cellular localization of two critical non-nuclear progesterone receptors in the ovine corpus luteum during the estrous cycle and early pregnancy

The study aimed to investigate the expression and cellular localization of two critical non-nuclear progesterone receptors, including membrane-associated-progesterone-receptor-component-1 (PGRMC1) and progestin and adipoQ receptor family member 7 (PAQR7) throughout the estrous cycle and early pregnancy in ovine corpus luteum (CL). Ewes were randomly grouped into cyclic (C, n = 4 per group) or pregnant (P, n = 4 per group) groups. Following slaughtering, the CL was obtained from both cyclic and pregnant ewes on days 12 (C12 and P12), 16 (C16 and P16), and 22 (C22 and P22). Western blotting and RT-qPCR were utilized to assess the expression levels of PGRMC1 and PAQR7, whereas immunohistochemistry was performed to determine the localization of PGRMC1 and PAQR7 in CL. Data were evaluated by one-way ANOVA, and the P < 0.05 was considered a significant difference. PGRMC1 was shown to be expressed in both small and large luteal cells and endothelial cells in CL, while PAQR7 expression was only found in small and large luteal cells. Compared to cycle days, pregnancy increased the expression of PGRMC1. PAQR7 did not differ during early pregnancy but reduced during the functional luteolysis stage (C16). mRNA and protein expression patterns for PGRMC1 and PAQR7 were similar on the studied days. This is the first study that demonstrates the expression and cellular localization of PGRMC1 and PAQR7 in ovine CL. We suggest that these receptors could execute a significant role in the ovine CL life span in both cyclic changes and the establishment of pregnancy.

Cell-Specific Expression Pattern of Toll-Like Receptors and Their Roles in Animal Reproduction

Toll-like receptors (TLRs), a part of the innate immune system, have critical roles in protection against infections and involve in basic pathology and physiology. Secreted molecules from the body or pathogens could be a ligand for induction of the TLR system. There are many immune and non-immune types of cells that express at a least single TLR on their surface or cytoplasm. Those cells may be a player in a defense system or in the physiological regulation mechanisms. Reproductive tract and organs contain different types of cells that have essential functions such as hormone production, providing an environment for embryo/fetus, germ cell production, etc. Although lower parts of reproductive organs are in a relationship with outsider contaminants (bacteria, viruses, etc.), upper parts should be sterile to provide a healthy pregnancy and germ cell production. In those areas, TLRs bear controller or regulator roles. In this chapter, we will provide current information about physiological functions of TLR in the cells of the reproductive organs and tract, and especially about their roles in follicle selection, maturation, follicular atresia, ovulation, corpus luteum (CL) formation and regression, establishment and maintenance of pregnancy, sperm production, maturation, capacitation as well as the relationship between TLR polymorphism and reproduction in domestic animals. We will also discuss pathogen-associated molecular patterns (PAMPs)-induced TLRs that involve in reproductive inflammation/pathology.

Proteomic fertility markers in ram sperm

Precise estimation of ram fertility is important for sheep farming to sustain reproduction efficiency and profitability of production. There, however, is no conventional method to accurately predict ram fertility. The objective of this study, therefore, was to ascertain proteomic profiles of ram sperm having contrasting fertility phenotypes. Mature rams (n = 66) having greater pregnancy rates than average (89.4 ± 7.2%) were assigned into relatively-greater fertility (GF; n = 31; 94.5 ± 2.8%) whereas those with less-than-average pregnancy rates were assigned into a lesser-fertility (LF; n = 25; 83.1 ± 5.73%; P = 0.028) group. Sperm samples from the outlier greatest- and least-fertility rams (n = 6, pregnancy rate; 98.4 ± 1.8% and 76.1 ± 3.9%) were used for proteomics assessments utilizing Label-free LC-MS/MS. A total of 997 proteins were identified, and among these, 840 were shared by both groups, and 57 and 93 were unique to GF and LF, respectively. Furthermore, 190 differentially abundant proteins were identified; the abundance of 124 was larger in GF while 66 was larger in LF rams. The GF ram sperm had 79 GO/pathway terms in ten major biological networks while there were 47 GO/pathway terms in six biological networks in sperm of LF rams. Accordingly, differential abundances of sperm proteins between sperm of GF and LF rams were indicative of functional implications of sperm proteome on male fertility. The results of this study emphasize there are potential protein markers for evaluation of semen quality and estimation of ram sperm fertilizing capacity.

Sperm Functional Genome Associated With Bull Fertility

Bull fertility is an important economic trait in sustainable cattle production, as infertile or subfertile bulls give rise to large economic losses. Current methods to assess bull fertility are tedious and not totally accurate. The massive collection of functional data analyses, including genomics, proteomics, metabolomics, transcriptomics, and epigenomics, helps researchers generate extensive knowledge to better understand the unraveling physiological mechanisms underlying subpar male fertility. This review focuses on the sperm phenomes of the functional genome and epigenome that are associated with bull fertility. Findings from multiple sources were integrated to generate new knowledge that is transferable to applied andrology. Diverse methods encompassing analyses of molecular and cellular dynamics in the fertility-associated molecules and conventional sperm parameters can be considered an effective approach to determine bull fertility for efficient and sustainable cattle production. In addition to gene expression information, we also provide methodological information, which is important for the rigor and reliability of the studies. Fertility is a complex trait influenced by several factors and has low heritability, although heritability of scrotal circumference is high and that it is a known fertility maker. There is a need for new knowledge on the expression levels and functions of sperm RNA, proteins, and metabolites. The new knowledge can shed light on additional fertility markers that can be used in combination with scrotal circumference to predict the fertility of breeding bulls. This review provides a comprehensive review of sperm functional characteristics or phenotypes associated with bull fertility.

Advancing Semen Evaluation Using Lipidomics

Developing a deeper understanding of biological components of sperm is essential to improving cryopreservation techniques and reproductive technologies. To fully ascertain the functional determinants of fertility, lipidomic methods have come to the forefront. Lipidomics is the study of the lipid profile (lipidome) within a cell, tissue, or organism and provides a quantitative analysis of the lipid content in that sample. Sperm cells are composed of various lipids, each with their unique contribution to the overall function of the cell. Lipidomics has already been used to find new and exciting information regarding the fatty acid content of sperm cells from different species. While the applications of lipidomics are rapidly evolving, gaps in the knowledge base remain unresolved. Current limitations of lipidomics studies include the number of available samples to analyze and the total amount of cells within those samples needed to detect changes in the lipid profiles across different subjects. The information obtained through lipidomics research is essential to systems and cellular biology. This review provides a concise analysis of the most recent developments in lipidomic research. This scientific resource is important because these developments can be used to not only combat the reproductive challenges faced when using cryopreserved semen and artificial reproductive technologies in livestock such as cattle, but also other mammals, such as humans or endangered species.

Cellular and Functional Physiopathology of Bull Sperm With Altered Sperm Freezability

The objective of this study was to ascertain the cellular and functional parameters as well as ROS related changes in sperm from bulls with varied sperm freezability phenotypes. Using principal component analysis (PCA), the variables were reduced to two principal components, of which PC1 explained 48% of the variance, and PC2 explained 24% of the variance, and clustered animals into two distinct groups of good freezability (GF) and poor freezability (PF). In ROS associated pathophysiology, there were more dead superoxide anion positive (Dead SO+) sperm in GF bulls than those in PF (15.72 and 12.00%; P = 0.024), and that Dead SO+ and live hydrogen positive cells (live H₂O₂+) were positively correlated with freezability, respectively (R² = 0.55, P < 0.0130) and (r_s = 0.63, P = 0.0498). Related to sperm functional integrity, sperm from PF bulls had greater dead intact acrosome (DIAC) than those from GF bulls (26.29 and 16.10%; P = 0.028) whereas sperm from GF bulls tended to have greater live intact acrosome (LIAC) than those from PF bulls (64.47 and 50.05%; P = 0.084). Sperm with dead reacted acrosome (DRAC) in PF bulls were greater compared to those in GF (19.27 and 11.48%; P = 0.007). While DIAC (R² = 0.56, P = 0.0124) and DRAC (R² = 0.57, P < 0.0111) were negatively correlated with freezability phenotype, LIAC (R² = 0.36, P = 0.0628) was positively correlated. Protamine deficiency (PRM) was similar between sperm from GF and PF bulls (7.20 and 0.64%; P = 0.206) and (r_s = 0.70, P = 0.0251) was correlated with freezability. Sperm characteristics associated with cryotolerance are important for advancing both fundamental andrology and assisted reproductive technologies across mammals.

Relative abundance and localization of interferon-stimulated gene 15 mRNA transcript in intra- and extra-uterine tissues during the early stages of pregnancy in sheep

The aim of this study was to investigate relative abundance and localization of ISG15 mRNA transcript in intra-uterine (trophoblast, endometrium) and extra-uterine (hypothalamus, anterior pituitary, corpus luteum) tissues before and during the period of conceptus implantation. Multiparous ewes (n = 16) were randomly allotted into four groups: pregnant or estrous cyclic on days of 12 and 16 (n = 4 per group) following estrus. Relative abundances of ISG15 mRNA transcript were determined in the endometrium, corpus luteum, hypothalamus, and anterior-pituitary using real time quantitative PCR. Localization of ISG15 mRNA transcript was evaluated using in situ hybridization. The presence of ISG15 mRNA transcript was only visualized in intra-uterine tissues including the endometrium and trophoblast on day 12 of pregnancy. The ISG15 mRNA transcript was detected in all tissues evaluated on day 16 of pregnancy. The abundance of ISG15 mRNA transcript was greater in the endometrium on day 12 of pregnancy than at other days when evaluations occurred while in all other tissues except the hypothalamus there were large abundances of ISG15 mRNA on day 16 of pregnancy. It is concluded that the ISG15 mRNA transcript is only present in intra-uterine tissues before conceptus implantation. The ISG15 mRNA transcript, however, is present in extra-uterine tissues of ewes during implantation probably due to an increased amount of interferon-tau in blood circulation that is produced by the developing embryo. Results also indicate, for the first time, that pregnancy is associated with an intra-hypothalamus and anterior pituitary increased abundance of ISG15 mRNA transcript in ewes.

Expression profile of Toll-like receptor 4 in rat testis and epididymis throughout postnatal development

Toll-like receptors (TLRs) belonging to pattern recognition receptors are involved in maintaining testicular and epididymal immune homeostasis. The purpose of the current study was to investigate TLR4 expression in rat testis and epididymis throughout postnatal development. Weak staining was detected in peritubular myoid cells and immature Sertoli cells while no staining was observed in gonocytes during prepubertal period. However, TLR4 expression began to appear in spermatocytes in pubertal period and gradually increased in spermatids. An intense staining was observed in steps 5-19 spermatids in post pubertal and mature periods. Similarly, TLR4 expression in the testes steadily increased from pubertal period to mature period. Puberty also caused a significant increase in TLR4 expression in epididymis. TLR4 expression in cauda epididymis was lower as compared to those of other epididymal segments. The majority of epididymal epithelial cells exhibited apical TLR4 expression, whereas basal cells showed intense intracytoplasmic immunoreaction. We detected an intense staining in epididymal smooth muscle cells. The expression levels of TLR4 showed dynamic changes in both spermatogenic cells, and entire testicular and epididymal tissues during postnatal development. These results suggest that TLR4 expression contributes not only to inflammation but also to the development of spermatogenic cells.

Amino Acids of Seminal Plasma Associated With Freezability of Bull Sperm

Sperm cryopreservation is an important technique for fertility management, but post-thaw viability of sperm differs among breeding bulls. With metabolites being the end products of various metabolic pathways, the contributions of seminal plasma metabolites to sperm cryopreservation are still unknown. These gaps in the knowledge base are concerning because they prevent advances in the fundamental science of cryobiology and improvement of bull fertility. The objective of this study was to test the hypothesis that seminal plasma amino acids are associated with freezability of bull sperm. To accomplish this objective, amino acid concentrations in seminal plasma from seven bulls of good freezability (GF) and six bulls of poor freezability (PF) were quantified using gas chromatography–mass spectrometry (GC–MS). Multivariate and univariate analyses were performed to identify potential freezability biomarkers. Pathways and networks analyses of identified amino acids were performed using bioinformatic tools. By analyzing and interpreting the results we demonstrated that glutamic acid was the most abundant amino acid in bull seminal plasma with average concentration of 3,366 ± 547.3 nM, which accounts for about 53% of total amino acids. The other most predominant amino acids were alanine, glycine, and aspartic acid with the mean concentrations of 1,053 ± 187.9, 429.8 ± 57.94, and 427 ± 101.3 nM. Pearson’s correlation analysis suggested that phenylalanine concentration was significantly associated with post-thaw viability (r = 0.57, P-value = 0.043). Significant correlations were also found among other amino acids. In addition, partial least squares-discriminant analysis (PLS-DA) bi-plot indicated a distinct separation between GF and PF groups. Phenylalanine had the highest VIP score and was more abundant in the GF groups than in the PF groups. Moreover, pathway and network analysis indicated that phenylalanine contributes to oxidoreductase and antioxidant reactions. Although univariate analysis did not yield significant differences in amino acid concentration between the two groups, these findings are significant that they indicate the potentially important roles of amino acids in seminal plasma, thereby building a foundation for the fundamental science of cryobiology and reproductive biotechnology.

Spatiotemporal expression patterns of natriuretic peptides in rat testis and epididymis during postnatal development

Natriuretic peptide (NP) family is composed of atrial, brain and C-type NP (NPPA, NPPB and NPPC). Here, we aimed to investigate NP expression in testis and epididymis during postnatal development. NPPA expression was observed in gonocytes at prepubertal period but in only spermatocytes in pachytene and leptotene/zygotene stage at pubertal period. In prepubertal and pubertal periods, we detected NPPB expression in only Leydig cells. However, NPPC expression was detected in all of the gonocytes and Sertoli cells, spermatocytes and some interstitial cells in prepubertal and pubertal periods. In postpubertal and mature periods, NPPA and NPPB staining were detected in Leydig cells, elongated and round spermatids but not in spermatogonia and spermatocytes. However, we observed NPPC expression in all cells of the seminiferous tubules and Leydig cells in the postpubertal and mature periods. Epididymal epithelium showed intense NPPC expression during postnatal period but weak NPPA and NPPB expression in prepubertal and pubertal periods. The expression of three NPs in the testis significantly increased after puberty. In conclusion, puberty had a significant effect on NP expression in testis. Unlike NPPA and NPPB, expression of NPPC in all cells of the seminiferous tubule suggests that NPPC is effective in each step of spermatogenesis.

Advances in Cryopreservation of Bull Sperm

Cryopreservation of semen and artificial insemination have an important, positive impact on cattle production, and product quality. Through the use of cryopreserved semen and artificial insemination, sperm from the best breeding bulls can be used to inseminate thousands of cows around the world. Although cryopreservation of bull sperm has advanced beyond that of other species, there are still major gaps in the knowledge and technology bases. Post-thaw viability of sperm is still low and differs significantly among the breeding bulls. These weaknesses are important because they are preventing advances both in fundamental science of mammalian gametes and reproductive biotechnology. Various extenders have been developed and supplemented with chemicals to reduce cryodamage or oxidative stress with varying levels of success. More detailed insights on sperm morphology and function have been uncovered through application of advanced tools in modern molecular and cell biology. This article provides a concise review of progress in the cryopreservation of bull sperm, advances in extender development, and frontiers using diverse techniques of the study of sperm viability. This scientific resource is important in animal biotechnology because with the advances in discovery of sperm fertility markers, there is an urgent need to improve post-thaw viability and fertility of sperm through enhanced cryopreservation for precision agriculture to produce food animals to ensure food security on the global scale.

Expression pattern of galectin-1 and galectin-3 in rat testes and epididymis during postnatal development

Galectins are a family of lectins-binding beta-galactosides involved in a variety of extracellular and intracellular processes, thereby contributing to homeostasis, cell adhesion, cellular turnover, and immunity. This study aimed to determine the localization and expression of galectin-1 (Gal-1) and galectin-3 (Gal-3) in the testis and epididymis of rats at postnatal [(prepubertal (day 5), pubertal (day 20), postpubertal (day 50) and mature (day 70)] periods by using immunohistochemistry and Western blotting. Gal-1 and Gal-3 were differentially expressed in different types of cells in the testis and epididymis during postnatal development. While we detected Gal-1 expression in some spermatogenic cells and Leydig cells in the testis, not in the epididymal epithelium, Gal-3 was expressed in Sertoli cells, peritubular myoid cells, Leydig cells, smooth muscles and interstitial CD68-positive macrophages. Epithelial cells of the corpus and cauda epididymis showed an intense Gal-3 expression. Gal-1 expression was higher in the testis than in the epididymis on days 50 and 70. The expression of Gal-3 in the testis increased from the prepubertal to mature period. While the expression difference of Gal-3 was not statistically significant in the testis and epididymis until puberty, Gal-3 expression in the postpubertal and mature periods was higher in the epididymis. The expression of Gal-3 in the corpus and cauda epididymis was higher than that in the caput epididymis. In conclusion, our findings suggest that puberty has potential regulatory effect on the expression of galectins in testis and epididymis of rats. Gal-1 and 3 may play a role in the development of the reproductive system and the preservation of the immune-privileged environment in the testis, due to their pro-apoptotic and anti-apoptotic functions. The presence of intense expression of Gal-3 in the corpus and cauda epididymis may contribute to the maturation and storage of spermatozoa.

Pentoxifylline May Restore Kanamycin-Induced Renal Damage in Rats

Background: Kidney damage can be caused by many factors, such as using certain drugs in high doses or over the longterm. The use of one such group of drugs, aminoglycosides, which act as Gram-negative antibacterial therapeutic agents,can lead to nephrotoxicity. It has been hypothesized that aminoglycoside-induced nephrotoxicity might be prevented byusing pentoxifylline, which has antioxidant and anti-inflammatory effects and improves microcirculation. The objectiveof this present research was to determine the protective effects of pentoxifylline on kanamycin-induced kidney damage.Materials, Methods & Results: Thirty-two male Wistar rats were divided into four groups as follows: control, pentoxifylline,kanamycin, and kanamycin + pentoxifylline. The control group received intraperitoneal (IP) injections of 0.5 mL normalsaline solution once a day (d) (SID) for 20 d; the pentoxifylline group received IP injections of 50 mg/kg pentoxifyllinetwice a day (BID) for 20 d, the kanamycin group received subcutaneous (SC) injections of 500 mg/kg kanamycin SID for20 d, and the kanamycin + pentoxifylline group received both SC injections of 500 mg/kg kanamycin SID and IP injectionsof 50 mg/kg pentoxifylline BID for 20 d. At the end of 20 d, blood samples were taken from the heart by cardiac punctureunder general anesthesia. After euthanizing the rats by cervical dislocation under anesthesia, the kidneys were immediatelyremoved, relative kidney weights were calculated, and routine pathologic evaluations were conducted. Hemogramparameters were measured using a blood cell count apparatus and serum biochemical parameters were measured usingan autoanalyzer. Kanamycin also caused (P < 0.05) tubular degeneration and tubular dilatation. Although pentoxifyllinesignificantly reduced the level of kanamycin-induced tubular degeneration (P < 0.05), it did not significantly reduce tubulardilatation. Increases in relative kidney weights (P < 0.05) and in interstitial mononuclear cell (MNC) infiltrates wereobserved in the kanamycin and kanamycin + pentoxifylline groups compared to those in the control and pentoxifyllinegroups. Statistically significant changes were determined in the levels of some hemogram and biochemical parameterswithin reference ranges (P < 0.05).Discussion: In this study, both tubular degeneration and dilatation were observed in the kanamycin group. Pentoxifyllineinhibited (P < 0.05) kanamycin-induced tubular degeneration and appeared to also reduce tubular dilatation, although thisreduction was not significant. Tubular necrosis, epithelial edema of proximal tubules, tubular fibrosis, and perivascularinflammation might also be observed in aminoglycoside-induced nephrotoxicity. In current research, pentoxifylline preventedtubular damage induced by kanamycin, but did not inhibit infiltration by MNCs. Pentoxifylline also amelioratedamikacin- or gentamycin-induced histopathologic changes, especially those associated with tubular structures. The protectiveeffects of pentoxifylline on kanamycin-induced tubular nephrotoxicity in this research might be a result of its stimulatingthe production of prostaglandin, a vasodilator, and of its improving microcirculation. Although the anti-inflammatoryeffects of pentoxifylline have been reported, these did not inhibit kanamycin-induced infiltration by interstitial MNCs inthe present study. These results could indicate that the anti-inflammatory effects of pentoxifylline are not obvious and/orare dose dependent. Statistically significantly changes were determined in the levels of some hemogram and biochemicalparameters in reference ranges. However, these changes were within the reference ranges for rats. These results suggestedthat kanamycin-induced tubular degeneration and dilatation might be prevented by administering pentoxifylline.

A Cardioprotective Role of Nerium oleander with the Expression of Hypoxia Inducible Factor 2A mRNA by Increasing Antioxidant Enzymes in Rat Heart Tissue

Background: Nerium oleander (NO) distillate is used to either protect heart cells against oxidative stress or reduce the risk of cardiovascular disease by regulating the production of reactive oxygen species. Hypoxia-inducible factors (HIFs) regulate cellular antioxidant defense mechanisms under hypoxic conditions in which heart cells survive; however, the key responsible mechanism of NO distillate for cardioprotection remains elusive. The objective of this study was to evaluate the effects on heart tissue at different time intervals after administering NO distillateintraperitoneally (IP) while considering the transcriptional regulation of HIFs and representative antioxidant enzymes.Materials, Methods &amp; Results: The NO plant was chopped, and distillated water was added. The mixture was distilled, and the distillate separated and collected into tubes, after which it was lyophilized to obtain dry material. Twenty male Wistar albino rats (2-3 month-old, 250-300 geach) were used in the study. The rats were randomly divided into four groups. The control group (n = 5) received IP injections of saline; the remaining 15 rats received IP injections of a single dose of 7.5 mL NO distillate. The NO distillate injected rats were divided into three groupsaccording to the time from injection to harvest the heart tissue samples. The tissues were collected at 0 h (control; n = 5), 2 h (group 2; n = 5), 4 h (group 3; n = 5), and 8 h (group 4; n = 5) after injection and under general anesthesia (60 mg/kg ketamine, IP + 10 mg/kg xylazine, IP).Quantitative polymerase chain reaction (qPCR) was used to assess the expression profiles of the genes of interest in the heart tissues. Hypoxanthine phosphoribosyltransferase was used as the reference gene. The expression of manganese superoxide dismutase (MnSOD) mRNA was in a steady state level between the control group and group 2 (P &gt; 0.05); however, it significantly increased in group 3 and 4 compared with that in the control (P &lt; 0.05). Expression of catalase (CAT) mRNA was significantly higher in group 2 than in the control group (P &lt; 0.05) although it was lower in group 3 and 4 than in group 2 (P &lt; 0.05); however, it appeared to be similar among the control group, group 3, and group 4 (P &gt; 0.05). Copper (Cu) SOD mRNA was equallyexpressed in both the control group and group 2 (P &gt; 0.05) but was lower in group 3 and 4 than in group 2 (P &lt; 0.05). Expressions of HIF1A, HIF2A, and HIF3A mRNA were detected in the rat heart tissues in the control and 2, 4, and 8 h after administration of NO distillate. Expression ofHIF1A mRNA was in a steady state and did not differ among groups 2, 3, and 4 (P &gt; 0.05). Similarly, the expression of HIF2A mRNA did not change between the control group and group 2 (P &gt; 0.05); however, it was higher in group 3 than in the control (P &lt; 0.05) and tended to behigher in group 3 than in group 2 (P = 0.063). HIF3A mRNA expression did not change significantly in the heart tissue of any of the groups (P &gt; 0.05).Discussion: The present study using rats determined that MnSOD, CAT, CuSOD, HIF1A, HIF2A, and HIF3A mRNA are expressed in the heart tissues after administration of NO distillate. The increased expression of HIF2A mRNA after 4 h in accordance with a rise in CAT mRNA after 2 h, and MnSOD mRNA after 4 and 8 h might confirm the role of HIF2A mRNA in oxidative stress defense by regulating antioxidant enzymes; consequently, this study may expand our understanding of uses of NO distillate with respect to molecular pathways.

Expression of ADAMTS-7 in myocardial dystrophy associated with white muscle disease in lambs

The aim of the present study was to investigate the role of ADAMTS-7 gene in the pathogenesis of myocardial dystrophy associated with white muscle disease (WMD) in lambs. A total of 217 cardiac tissue samples from lambs with WMD were used in the study. Histopathological sections of the samples were stained with hematoxylin-eosin (HE) and examined using Western-blot, real-time PCR (RT-PCR) and immunohistochemistry for ADAMTS-7 gene expression, and the findings were statistically evaluated. Histopathological examinations revealed fibrosis associated with hyalinization, necrosis and granular calcifications in cardiomyocytes. Western blot and RT-PCR showed a statistically significant upregulation of ADAMTS-7 (p<0.05) (p<0.05). Immunohistochemical analyses showed that immunopositive cell numbers significantly high for ADAMTS-7 (p<0.05). The study has revealed that ADAMTS-7 gene is significantly expressed in myocardial dystrophy associated with WMD in addition to its role in the pathogenesis of this disease.

109 EXPRESSION OF GENES RELATED TO ENDOMETRIAL RECEPTIVITY IN EQUINE ENDOMETRIUM DURING THE ESTROUS CYCLE AND EARLY PREGNANCY

A set of genes that display differential expression levels in the reproductive tract could serve as beneficial markers of endometrial receptivity. SERPINA14 is present in the uterus during pregnancy and suppresses lymphocyte accumulation. Osteopontin is the ligand of integrin β3 and enables trophoblast communication during implantation. Leukemia inhibitory factor (LIF) is involved in inflammatory cell signalling and contributes to implantation by regulating immune cells. The objective was to assess the expression of SERPINA14, osteopontin, and LIF mRNAs in the equine endometrium during the oestrous cycle and early pregnancy. Biopsies were obtained from mares on day of ovulation (d 0, n = 4), late diestrus (LD, n = 4, high progesterone [P4]), and after luteolysis at the beginning of oestrus phase (AL, n = 4, <1 ng mL–1 P4) of the cycle. Biopsies were also taken on days 14 (P14, n = 4), 18 (P18, n = 4), and 22 (P22; n = 4) of pregnancy. Relative mRNA expression levels of genes were quantified using real-time quantitative RT-qPCR in duplicate. Data were analysed using one-way ANOVA, and l.s.d. test was applied. Both the oestrous cycle and early pregnancy increased SERPINA14 mRNA levels compared to d0. Expression of LIF mRNA was not significantly regulated except for a decline at AL. Expression of osteopontin mRNA was up-regulated during the oestrous cycle at LD while early pregnancy inhibited this up-regulation. The results suggest that the genes studied related to endometrial receptivity are strictly regulated accordingly to the stage of oestrous cycle, probably by circulating ovarian steroids, specifically progesterone, and pregnancy-associated factors are also involved in this regulation. This project was partially funded by TUBITAK 107O035 to AG and DUBAP 14VF12 to MOA. MH was supported by OYP 2013-090.

121 EXPRESSION OF HYALURONAN SYSTEM COMPONENTS IN THE EARLY PREGNANT OVINE ENDOMETRIUM

Hyaluronan (HA; hyaluronic acid), a member of glycosaminoglycans (GAG) family, is the main polysaccharide and is expressed in almost all tissues including those of the reproductive tract. Three different hyaluronic acid-synthase (HAS) enzymes, HAS1, HAS2, and HAS3, synthesise HA. The action of HA depends on its molecular size and its cell surface receptor (CD44). Hyaluronidases (HYAL) are a group of enzymes, HYAL-1 and HYAL-2, that degrade HA. Roles of the HA system in reproductive events include oocyte maturation, fertilization, and implantation. It is also known that ovarian steroids, specifically progesterone, regulate the HA system in the endometrium. Moreover, HA-mediated cell signalling participates in embryonic development. The aim of this study was to evaluate expression of the HA system at the mRNA level in the early pregnant ovine endometrium at pre-implantation stage. Therefore, endometrial tissue samples were collected on Day 13 of the oestrous cycle (n = 10) and pregnancy (n = 14). Relative mRNA expression levels of HA system genes were quantified using quantitative RT-qPCR. Data were analysed using one-way ANOVA and l.s.d. test. All of the studied components of the HA system (HAS1, HAS2, HAS3, HYAL1, HYAL2, and CD44) were expressed in the ovine endometrium. Steady-state mRNA levels of HAS1, HYAL1, HYAL2, and CD44 were not significantly different between cyclic and early pregnant ovine endometrium on Day 13. However, expression of HAS2 and HAS3 appeared to be down-regulated in early pregnancy. Considering that both cyclic and pregnant endometrium on Day 13 is under the influence of progesterone, detected differential regulation of some components of HA system in the ovine endometrium may be directly related to the effects of the presence of an embryo. The role of the HA system in ovine endometrium at later stages of pregnancy warrants further investigation. Partially funded by TUBITAK-112R022 to ZK and SUBAP to AG.

111 EXPRESSION OF PHOSPHOLIPASE A2 ISOFORMS IN EQUINE ENDOMETRIUM DURING THE ESTROUS CYCLE AND EARLY PREGNANCY

Phospholipase A2 (PLA2) is involved in the synthesis of prostaglandins (PG) as it releases arachidonic acid from the membrane phospholipids to be a precursor for cyclooxygenase enzymes. Therefore, it is critically important during luteolysis and at the time of maternal recognition of pregnancy. The embryo must attenuate endometrial PGF2α production, whereas PGE2 is considered to be luteoprotective. Furthermore, implantation also requires the action of PGs. A balance should be maintained in PG synthesis in the endometrium. The objective of this study was to evaluate the expression of isoforms of PLA2 (cytosolic [cPLA2], secretory [PLA2], and calcium independent [iPLA2]) in equine endometrium during the oestrous cycle and early pregnancy. Biopsies were obtained from mares on the day of ovulation (d0, n = 4), late diestrus (LD, n = 4, high progesterone [P4]), and after luteolysis in the beginning of oestrus phase (AL, n = 4, <1 ng mL–1 P4) of the cycle. Biopsies were also taken on days 14 (P14, n = 4), 18 (P18, n = 4), and 22 (P22; n = 4) of pregnancy. Relative mRNA expression levels of genes were quantified using real-time quantitative RT-qPCR. Data were analysed using one-way ANOVA and l.s.d. test. Compared with the day of oestrus (d0), steady-state levels of cPLA2 and sPLA2 were down-regulated at LD, where P4 was high, and expression of both were up-regulated again at AL. In contrast, iPLA2 expression was higher at LD and then decreased again at AL. Pregnancy decreased expression of cPLA2 and sPLA2 mRNA at P14 and P18 compared with their respective cycle days. Late diestrus elevation in the expression of iPLA2 was suppressed by pregnancy at P14; however, it was up-regulated later in pregnancy at P22. The results suggest that expression of cPLA2 and sPLA2 is negatively correlated with circulating progesterone concentrations. Pregnancy further inhibits their expression in the equine endometrium. However, iPLA2 expression seems to be positively correlated by progesterone presence and its expression increased as equine pregnancy advanced. This project was partially funded by TUBITAK 107O035 and SUBAP to AG.