TheriogenologyPub Date : 2024-11-20DOI: 10.1016/j.theriogenology.2024.11.014
Canqiang Lu, Yun Feng, Zhenhua Tang, Ruru Jia, Fan Xia, Tingzi Yu, Heng Wang, Hongfang Mo, Deshun Shi, Fenghua Lu
{"title":"Supplementation with L-kynurenine during in vitro maturation improves bovine oocytes developmental competence through its antioxidative action.","authors":"Canqiang Lu, Yun Feng, Zhenhua Tang, Ruru Jia, Fan Xia, Tingzi Yu, Heng Wang, Hongfang Mo, Deshun Shi, Fenghua Lu","doi":"10.1016/j.theriogenology.2024.11.014","DOIUrl":"https://doi.org/10.1016/j.theriogenology.2024.11.014","url":null,"abstract":"<p><p>Oxidative stress impairs the developmental potential of oocytes during in vitro maturation (IVM). L-kynurenine (L-KYN), an endogenous metabolite, exhibits antioxidant, anti-inflammatory and neuroprotective effects. This work aimed to evaluate the potential effects of L-KYN on bovine oocyte IVM and its mechanisms. Different concentrations of L-KYN (0, 10, 50, 100, and 200 μmol/L) were supplemented to bovine oocyte IVM medium. Results shown a notable enhancement in the oocyte maturation rate and the subsequent zygote cleavage and blastocyst formation rate when the L-KYN concentration reached 100 μmol/L. Further analysis revealed that this treatment effectively down-regulated expression levels of genes to cumulus cell apoptosis (Bax and Caspase3), up-regulated expression levels of genes to cumulus cell expansion (HAS2, PTX3, and PTGS2) and oocyte antioxidant (GPX4 and CAT). L-KYN supplementation also effectively increased glutathione (GSH) levels, promoted oocytes mitochondrial activity, enhanced DNA repairability, deceased reactive oxygen species (ROS) levels, and reduced apoptosis. In conclusion, adding 100 μmol/L of L-KYN to IVM medium could enhance bovine oocyte quality and the subsequent embryonic development. L-KYN could be a potential antioxidant supplement for bovine oocyte maturation in vitro.</p>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"233 ","pages":"53-63"},"PeriodicalIF":2.4,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142695784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TheriogenologyPub Date : 2024-11-19DOI: 10.1016/j.theriogenology.2024.11.011
Penelope Banchi, Alessia Bertero, Michela Corrò, Barbara Colitti, Lorella Maniscalco, Ann Van Soom, Ada Rota
{"title":"Approaching the sterile womb theory in dogs and cats: A multi-technique investigation.","authors":"Penelope Banchi, Alessia Bertero, Michela Corrò, Barbara Colitti, Lorella Maniscalco, Ann Van Soom, Ada Rota","doi":"10.1016/j.theriogenology.2024.11.011","DOIUrl":"https://doi.org/10.1016/j.theriogenology.2024.11.011","url":null,"abstract":"<p><p>The study investigated whether bacterial seeding occurs in utero in dogs and cats using a multi-technique approach, including 16S rRNA gene sequencing, culture, and fluorescence in situ hybridization (FISH). Healthy pregnant bitches and queens (n = 8) undergoing ovariohysterectomy between 30 and 45 days of gestation were included. Placenta and amniotic fluid samples from two foetuses per dam, along with multiple controls (uterine serosa, sampling table, and surgeon's gloves), were collected and analysed. Bacterial sequences were detected in all foetal samples, with no significant differences in intra- and inter-sample diversity (i.e., alpha and beta diversities, respectively) based on sample type or species. However, the surgeon's gloves showed species-specific differences in bacterial composition. After removing control sequences, significant differences based on foeto-maternal units emerged. Moraxella spp. was cultured from the canine placenta with the highest bacterial load, and Burkholderia cepacia was isolated from two feline placentae. FISH showed low bacterial presence in 50 % of placentae without histological signs of inflammation. No bacterial growth was observed in amniotic fluid or control samples. A multi-technique approach, including multiple controls, is essential in studies involving low-biomass samples, as the results of the present study indicated that contamination could mask real bacterial composition of foetal samples. After decontamination, differences were observed based on the foeto-maternal unit. This study confirmed the presence of bacterial DNA in placental and amniotic fluid samples during mid-term, healthy pregnancies in dogs and cats. Bacterial DNA is not equivalent to living bacteria, hence bacterial DNA fragments in the uterus probably originate from the dam but are unlikely to indicate the presence of a resident foetal microbiome.</p>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"233 ","pages":"42-52"},"PeriodicalIF":2.4,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142693620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TheriogenologyPub Date : 2024-11-19DOI: 10.1016/j.theriogenology.2024.11.012
Simon K Walker, Alice C Weaver, Alyce M S Swinbourne, Jennifer M Kelly, David O Kleemann
{"title":"Improving the efficacy of progesterone pessary treatment for synchrony of estrus in the sheep.","authors":"Simon K Walker, Alice C Weaver, Alyce M S Swinbourne, Jennifer M Kelly, David O Kleemann","doi":"10.1016/j.theriogenology.2024.11.012","DOIUrl":"https://doi.org/10.1016/j.theriogenology.2024.11.012","url":null,"abstract":"<p><p>Treatment with intra-vaginal progesterone pessaries for synchrony of estrus is essential in fixed-time artificial insemination (AI) of sheep. Globally, the conventional 14-day pessary treatment is the mainstay of commercial AI programs. It has remained largely unchanged for many decades even though it is associated with variable patterns of estrus and often disappointing pregnancy rates. Until recently, an understanding of this variability has been elusive. Here we review research of the last 25 years and conclude that synchronising estrus and obtaining satisfactory pregnancy rates (≥75 %) following AI is more challenging than expected from the original research of the 1960s. In particular, conventional pessary treatment is unable to control the time of emergence of the ovulatory follicle and the resultant variability in follicle age affects fertility. Additionally, the pessary is unable to mitigate the effects of season, nutrition and cyclical status of the ewe on the timing of estrus. It is concluded that the inability of pessary treatment to produce a uniform synchrony together with the adverse effects on follicle quality are primarily responsible for variable pregnancy rates. However, there are strategies to improve AI success rates. The first involves controlling the time of emergence of the ovulatory follicle so that it occurs primarily during the most fertile period of pessary treatment (Days 7-9 of a 14-day treatment). The second involves improving the synchrony of estrus by enhancing circulating levels of progesterone late (Day 9) in the treatment period. The third involves the use of short-term pessary treatments (5-7 days) that avoid some of the abnormalities associated with conventional treatment. Finally, given the variability in the timing of estrus, we address the challenge of optimising the time of insemination, an essential requirement of successful AI programs.</p>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"233 ","pages":"24-31"},"PeriodicalIF":2.4,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142693631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TheriogenologyPub Date : 2024-11-16DOI: 10.1016/j.theriogenology.2024.11.004
Yame Fabres Robaina Sancler-Silva, Frederico Ozanam Papa, Alejandro Esteller-Vico, Edjalma Silva-Junior, Thalita Evani Silva de Oliveira, Hossam El-Sheikh Ali, Yatta Linhares Boakari, Marcela Souza E Freitas, Barry Allen Ball
{"title":"Beneficial effects of pentoxifylline on spermatogenesis and germ cell apoptosis in stallions subjected to scrotal heat stress.","authors":"Yame Fabres Robaina Sancler-Silva, Frederico Ozanam Papa, Alejandro Esteller-Vico, Edjalma Silva-Junior, Thalita Evani Silva de Oliveira, Hossam El-Sheikh Ali, Yatta Linhares Boakari, Marcela Souza E Freitas, Barry Allen Ball","doi":"10.1016/j.theriogenology.2024.11.004","DOIUrl":"https://doi.org/10.1016/j.theriogenology.2024.11.004","url":null,"abstract":"<p><p>This study evaluated the effects of oral pentoxifylline on testicular biometry, histology, and gene expression in stallions subjected to scrotal heat stress. Fourteen stallions were divided into three groups: Control (CRL, n = 4), Testicular Degeneration (DEG, n = 5), and Testicular Degeneration Treated with Pentoxifylline (DEG + PTX, n = 5). Testicular degeneration was induced by scrotal insulation, twice daily, over two consecutive days (D-1 and D0). Starting the next day (D1), oral pentoxifylline (17 mg/kg) was administered every 12 h for 30 days. Testicular biometry was measured using a caliper from D-5 to D60. On days 30 and 60, testicular biopsies were collected for histopathology and gene expression analysis of BAX, CASP8, CASP9, FAS, HSF1, and PTGS2 using RT-qPCR. Pentoxifylline reduced histological damage, with the DEG + PTX group showing less pronounced basal lamina undulation and seminiferous tubule atrophy compared to the DEG group. However, it did not fully prevent lesions like germ cell vacuolization, which was reflected macroscopically by a reduction in testicular volume in both degenerated groups. The protective effects of pentoxifylline on testicular tissue can be attributed to its ability to reduce BAX expression, prevent CASP8 and CASP9 activation, and promote cellular protective mechanisms through HSF1 activation at D30. These results highlight pentoxifylline's potential as a therapeutic agent for equine testicular damage due to scrotal heat stress, suggesting the need for further research on optimal dosage and treatment duration.</p>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"233 ","pages":"32-41"},"PeriodicalIF":2.4,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142693622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TheriogenologyPub Date : 2024-11-14DOI: 10.1016/j.theriogenology.2024.11.007
Osvaldo Bogado Pascottini, Alan D Crowe, Uxía Yáñez Ramil, Miel Hostens, Geert Opsomer, Mark A Crowe
{"title":"Perspectives in cattle reproduction for the next 20 years - A European context.","authors":"Osvaldo Bogado Pascottini, Alan D Crowe, Uxía Yáñez Ramil, Miel Hostens, Geert Opsomer, Mark A Crowe","doi":"10.1016/j.theriogenology.2024.11.007","DOIUrl":"https://doi.org/10.1016/j.theriogenology.2024.11.007","url":null,"abstract":"<p><p>Following a significant increase in herd and farm sizes after the removal of milk quotas in Europe, the past 10 years have seen a slight yet steady decline in the population of cattle. This includes a reduction of approximately 5 % in dairy and beef cattle. This trend is driven by various factors, such as changing market demands, economic shifts, and sustainability challenges in the livestock sector. Despite this, technological advancements in reproductive management have continued to enhance efficiency and sustainability, particularly in dairy production. The main areas of rapid development, which will continue to grow for improving fertility and management, include: i) genetic selection (including improved phenotypes for use in breeding programs), ii) nutritional management (including transition cow management), iii) control of infectious disease, iv) rapid diagnostics of reproductive health, v) development of more efficient ovulation/estrous synchronization protocols, vi) assisted reproductive management (and automated systems to improve reproductive management), vii) increased implementation of sexed semen and embryo transfer, viii) more efficient handling of substantial volumes of data, ix) routine implementation of artificial intelligence technology for rapid decision-making at the farm level, x) climate change and sustainable cattle production awareness, xi) new (reproductive) strategies to improve cattle welfare, and xii) improved management and technology implementation for male fertility. This review addresses the current status and future outlook of key factors that influence cattle herd health and reproductive performance, with a special focus on dairy cattle. These insights are expected to contribute to improved performance, health, and fertility of ruminants in the next 20 years.</p>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"233 ","pages":"8-23"},"PeriodicalIF":2.4,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142693564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TheriogenologyPub Date : 2024-11-13DOI: 10.1016/j.theriogenology.2024.11.008
Luis B Ferré, Maria Natalia Cerviño, Julian Jaeschke, Maximiliano Itterman, Jaime McLean, Agustin Aragon, Manuel Fernández, Matías Villa, Néstor Formia, Maria Jaureguiberry, Ramiro Rearte, Michael E Kjelland, Marcos G Colazo, Jordan M Thomas, Rodolfo Luzbel de la Sota
{"title":"Evaluation of GnRH- versus estradiol-based protocols for ovulation synchronization in postpartum Bos taurus grazing beef cows submitted to fixed-time artificial insemination.","authors":"Luis B Ferré, Maria Natalia Cerviño, Julian Jaeschke, Maximiliano Itterman, Jaime McLean, Agustin Aragon, Manuel Fernández, Matías Villa, Néstor Formia, Maria Jaureguiberry, Ramiro Rearte, Michael E Kjelland, Marcos G Colazo, Jordan M Thomas, Rodolfo Luzbel de la Sota","doi":"10.1016/j.theriogenology.2024.11.008","DOIUrl":"https://doi.org/10.1016/j.theriogenology.2024.11.008","url":null,"abstract":"<p><p>This study compared the effect of a 7-day estradiol- and a 7-day GnRH-based FTAI protocol versus a presynchronized GnRH-based FTAI protocol (7 & 7 GnRH) on pregnancy per AI (P/AI) in multiparous postpartum Angus cows. Cows were blocked according to presence/absence of a CL, body condition score, and days postpartum and assigned randomly to one of three treatments: I) 7-day EB (n = 368), estradiol benzoate (EB) and intravaginal progesterone-(P4)-releasing device (IVPD) on Day -10, prostaglandin F<sub>2α</sub> (PG), equine chorionic gonadotropin (eCG) and estradiol cypionate (ECP) at IVPD removal on Day -3 with FTAI done on Day -1 (54 ± 2 h after IVPD removal); II) 7-day GnRH (n = 367), GnRH at IVPD insertion on Day -10, PG and eCG at IVPD removal on Day -3 with GnRH and FTAI on Day 0 (66 ± 2 h after IVPD removal); and III) 7 & 7 GnRH (n = 361), PG at IVPD insertion on Day -17, GnRH on Day -10, IVPD removal, PG and eCG on Day -3 with GnRH and FTAI on Day 0 (66 ± 2 h after IVPD removal). Preovulatory follicle diameter, corpus luteum (CL) presence, CL area, and P4 concentration were determined at IVPD removal, as well as estrus expression at FTAI and P/AI between 35 and 40 days after FTAI. Plasma P4 concentrations at IVPD removal were greater (P < 0.05) in cows subjected to the 7-day GnRH or 7 & 7 GnRH protocols and a greater number of cows (P < 0.05) had at least one CL at IVPD removal compared to cows subjected to the 7-day EB protocol. However, the 7 & 7 GnRH protocol resulted in more cows with two CLs at IVPD removal compared to the other two protocols. Moreover, cows synchronized with the 7 & 7 GnRH protocol had larger preovulatory follicles (P < 0.05) and larger CL area at IVPD removal (P < 0.05), and a greater rate of estrus expression before FTAI (P < 0.05) than cows synchronized with the 7-day EB, whereas those variables were intermediate in cows synchronized with the 7-day GnRH. Pregnancy per AI was greater (P < 0.05) in cows treated with the 7 & 7 GnRH (63.5 %) treatment compared to the 7-day EB (51.4 %) and the 7-day GnRH (51.3 %) protocols. In summary, the 7 & 7 GnRH protocol enhanced circulating P4 before IVPD removal, increased estrus expression rate before FTAI, and improved P/AI in postpartum Bos taurus grazing beef cows.</p>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"233 ","pages":"1-7"},"PeriodicalIF":2.4,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142682905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TheriogenologyPub Date : 2024-11-08DOI: 10.1016/j.theriogenology.2024.11.002
Zheng Feng , Jia Song , Chenghong Lin , Siyu Wu , Yu Wang , Qingyuan Hui , Yinting Pan , Yiman Zou , Chaofeng Zeng , Jinbiao Guo , Yangli Pei
{"title":"Enhancing porcine oocyte quality and embryo development through natural antioxidants","authors":"Zheng Feng , Jia Song , Chenghong Lin , Siyu Wu , Yu Wang , Qingyuan Hui , Yinting Pan , Yiman Zou , Chaofeng Zeng , Jinbiao Guo , Yangli Pei","doi":"10.1016/j.theriogenology.2024.11.002","DOIUrl":"10.1016/j.theriogenology.2024.11.002","url":null,"abstract":"<div><div>During fetal development, primordial oocytes maintain their developmental potential through a ROS-minimizing metabolic mechanism. Maturation increases ROS levels, causing stress and damage, which are countered by in vivo antioxidants. In vitro maturation (IVM) worsens this due to fewer antioxidant presence and medium factors. To address this, we evaluated the effects of incorporating various natural antioxidants in the porcine oocyte IVM media. Our findings revealed that 10 μM Dendrobine (DEN), 1 μM Polydatin (PD), 20 μM Limonin (LIM), and 25 μM Nobiletin (NOB) significantly improved the first polar body extrusion rates (p < 0.05), reduced ROS, and increased GSH levels. Individual addition of 100 μg/mL Lycium barbarum polysaccharides (LBP), 0.1 μM Kaempferol (KAE), 250 μM Salidroside (SAL), 10 μM Curcumin (CUR), DEN, PD, LIM, and NOB to the porcine IVM system showed that KAE, LIM, NOB, and LBP treatments yielded the most favorable results. At the gene level, LIM, LBP, and NOB were found to upregulate the expression levels of GPX1, SIRT1, and TFAM, while downregulating Caspase3 and increasing the BCL2/BAX ratio. The inclusion of LIM, NOB, and LBP, either alone or in combination, into the IVM media effectively alleviated oxidative stress in porcine oocytes, decreased cell apoptosis, preserved mitochondrial membrane potential, and enhanced the blastocyst rate. These results offer valuable insights for optimizing the porcine oocyte IVM culture system.</div></div>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"232 ","pages":"Pages 96-108"},"PeriodicalIF":2.4,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142628675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Compatibility of dry incubator on in vitro production of bovine embryos","authors":"Haruhisa Tsuji , Hiroki Nagai , Sayaka Kobinata , Hinata Koyama , Atchalalt Khurchabilig , Noritaka Fukunaga , Yoshimasa Asada , Satoshi Sugimura","doi":"10.1016/j.theriogenology.2024.11.005","DOIUrl":"10.1016/j.theriogenology.2024.11.005","url":null,"abstract":"<div><div>Embryo culture is crucial to achieve successful outcomes in <em>in vi</em>tro production-embryo transfer for cattle. This study explored the innovative use of dry incubators for bovine embryo culture, building on their advantages in human medicine, such as reduced contamination risk, stable temperature control, and lower gas consumption. In this study, we examined changes in osmotic pressure, the <em>in vi</em>tro developmental potential of IVP embryos including the cleavage rate, blastocyst development rate, blastocyst diameter, and blastocyst cell number, morphokinetics, and the transcriptional profile of the blastocysts between humidified and dry incubators. Our research demonstrates the feasibility of this approach, showing that although the osmotic pressure gradually increases over the culture period (on day 8: 271.7 vs. 299.0, respectively; P = 0.09), it did not negatively affect the blastocyst formation rate (62.4 % vs. 69.8 %) and the morphological quality of blastocysts (diameter: 237.4 vs. 242.8, total cell number: 189.2 vs. 242.8). Embryos cultured in dry incubators exhibited morphokinetics comparable to those cultured in conventional humidified incubators. Furthermore, RNA-seq revealed that while a few genes showed changes, the transcriptomic profiles of blastocysts cultured in dry incubators were largely similar to those of blastocysts cultured in humidified incubators. These findings highlight the considerable potential of dry incubators for the <em>in vi</em>tro production of bovine embryos.</div></div>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"232 ","pages":"Pages 117-123"},"PeriodicalIF":2.4,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142628673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TheriogenologyPub Date : 2024-11-06DOI: 10.1016/j.theriogenology.2024.11.006
M.C. Lucy , K.G. Pohler
{"title":"North American perspectives for cattle production and reproduction for the next 20 years","authors":"M.C. Lucy , K.G. Pohler","doi":"10.1016/j.theriogenology.2024.11.006","DOIUrl":"10.1016/j.theriogenology.2024.11.006","url":null,"abstract":"<div><div>Ruminant species are important to human society due to their ability to convert human-inedible sources of energy and protein to human-edible food. Greater efficiency of meat and milk production will require the management of the complex reproductive biology of many cattle with a limited capacity and limited budget within a smaller, hotter, and more climatically erratic land area. The over-riding drivers of new reproductive technologies in North America will be smaller economic margins, larger herd size, fewer agricultural workers per farm, and a greater reliance on automation to offset the reduced agricultural labor force. Climate change and the possibility that consumers may dictate the procedures used for animal reproductive management may present additional challenges. The successes of the past 20 years (timed AI, genomic selection for fertility in both bulls and cows, automated estrus detection, chemical and ultrasonographic pregnancy diagnosis, and gender selected semen) will be improved upon in the next 20 years as most of these technologies can be optimized further. Improving embryo technologies and increasing our understanding of embryonic loss may provide the greatest challenges for the future. Researchers must attempt to devise practical methods to release more follicles from the primordial follicle pool so that a greater number of oocytes and embryos can be harvested from individual animals. Embryonic loss continues to be an unsolved question that cuts the total number of potential offspring by nearly one-third. The identification of fertile embryos in vitro, better methods of cryopreservation, and the optimization of methods of transfer into recipient animals may improve the efficiency of advanced embryo technologies. The derivation of oocytes, sperm, and embryos from pluripotent stem cells may yield a vast supply of gametes and embryos from genetically superior animals and radically change the reproductive management in the future.</div></div>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"232 ","pages":"Pages 109-116"},"PeriodicalIF":2.4,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142628677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TheriogenologyPub Date : 2024-11-05DOI: 10.1016/j.theriogenology.2024.11.003
Jianing Hu, Jie Li, Shanyou Zheng, Yan Chen, Yucheng Zhang, Jiguang Deng, Jiasheng Fan, Huiyan Xu, Yangqing Lu, Xingting Liu
{"title":"Oxidative phosphorylation decline and mitochondrial dynamics disequilibrium are involved in chicken large white follicle atresia","authors":"Jianing Hu, Jie Li, Shanyou Zheng, Yan Chen, Yucheng Zhang, Jiguang Deng, Jiasheng Fan, Huiyan Xu, Yangqing Lu, Xingting Liu","doi":"10.1016/j.theriogenology.2024.11.003","DOIUrl":"10.1016/j.theriogenology.2024.11.003","url":null,"abstract":"<div><div>In domestic hens, the atresia of large white follicles (LWFs) directly affects the number of follicles that enter the hierarchical development and ovulation. Figuring out factors responsible for LWFs atresia is helpful to improve egg production of hens. At the LWF stage, yellow yolk begins to be deposited into the follicles via receptor mediated endocytosis, which requires large amounts of ATP. Mitochondrial oxidative phosphorylation (OXPHOS) is the primary source of ATP for follicular development. However, it is not clear whether the OXPHOS is changed along LWFs atresia. In this study, firstly, differences in morphological appearance, histology, cell proliferation, apoptosis, OXPHOS and mitochondrial dynamics between LWFs and atretic large white follicles (ALWFs) in hens at the peak laying stage (35W) were determined to elucidate whether OXPHOS changes in ALWFs. Then, these differences of LWFs between the peak laying hens (35W-LWFs) and the late laying hens (70W-LWFs) were detected to confirm whether OXPHOS changes during LWFs atresia. The results showed that ALWFs exhibited a wrinkled surface with several hemorrhage spots, and numerous intercellular vacuoles, as well as severe nuclear pyknosis. Compared to LWFs, a higher cell apoptosis rate and a lower proliferation rate were observed in ALWFs. In ALWFs, OXPHOS declined as manifested by reductions in ATP levels, ATP synthetase abundance, NAD<sup>+</sup>, NADH and NAD<sup>+</sup>/NADH ratio, and mRNA levels of genes associated with OXPHOS complexes I-V. Meanwhile, mitochondrial dynamics disequilibrium was detected in ALWFs as the expression levels of proteins and genes related to mitochondrial fusion (MFN1, MFN2, and OPA1) decreased, while the expression levels of proteins and genes related to mitochondrial fission (DRP1 and FIS1) increased. Further, compared to 35W-LWFs, 70W-LWFs showed a histology resembling to ALWFs, manifested as a slightly loosen structure of granulosa layers, and a lower cell proliferation rate. Moreover, both lower OXPHOS and impaired mitochondrial dynamics were detected in 70W-LWFs. In conclusion, our results indicated that OXPHOS decline and mitochondrial dynamics disequilibrium are involved in LWFs atresia in laying hens.</div></div>","PeriodicalId":23131,"journal":{"name":"Theriogenology","volume":"232 ","pages":"Pages 87-95"},"PeriodicalIF":2.4,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142628679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}