This document is about gene editing mechanisms in animals to enhance certain specific characters in subsequent generations. Gene generation by gene editing is the current revolution in biology. Today it is possible to edit the genome using the CRISPR-Cas tool that allows you to cut and paste very precise DNA sequences like never before. Thus we can improve practically all those characteristics that are determined by a gene, and then completely modify the phenotype of any species.
{"title":"CRISPR and the animals of the future: How to avoid being in the past","authors":"A. Menchaca","doi":"10.18548/aspe/0010.12","DOIUrl":"https://doi.org/10.18548/aspe/0010.12","url":null,"abstract":"This document is about gene editing mechanisms in animals to enhance certain\u0000 specific characters in subsequent generations. Gene generation by gene editing is the\u0000 current revolution in biology. Today it is possible to edit the genome using the\u0000 CRISPR-Cas tool that allows you to cut and paste very precise DNA sequences like never\u0000 before. Thus we can improve practically all those characteristics that are determined by\u0000 a gene, and then completely modify the phenotype of any species.","PeriodicalId":36778,"journal":{"name":"Spermova","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44943971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The primary objective of implementing embryo transfer in meat operations is to accelerate the rate of genetic progress in the herd. Among the main factors that affect the use of these technologies are related to the nutrition, the management and the synchronization of the estrus. As a result of research conducted in the last 20 years, the use of the receptor has increased through the application of protocols that synchronize ovulation and allow the transfer of embryos without the need for oestrus detection, generally known as fixed-time embryo transfer. (FTET). Although these protocols have functioned well for several years, attention has recently been directed to the effect of estrus expression and estradiol concentrations during pre-ovulatory follicle growth on embryonic growth and pregnancy. The experiments reviewed in this document demonstrate that oestrus expression is positively associated with high pregnancy rates and reduced pregnancy losses in recipients receiving frozen / thawed bovine embryos produced in vitro and in vivo.
{"title":"Insemination and embryo transfer programs: Effect of estrous on pregnancy and\u0000 embryonic and fetal losses in bovine","authors":"Andres Vera-Cedeño, G. Bó","doi":"10.18548/aspe/0010.14","DOIUrl":"https://doi.org/10.18548/aspe/0010.14","url":null,"abstract":"The primary objective of implementing embryo transfer in meat operations is to\u0000 accelerate the rate of genetic progress in the herd. Among the main factors that affect\u0000 the use of these technologies are related to the nutrition, the management and the\u0000 synchronization of the estrus. As a result of research conducted in the last 20 years,\u0000 the use of the receptor has increased through the application of protocols that\u0000 synchronize ovulation and allow the transfer of embryos without the need for oestrus\u0000 detection, generally known as fixed-time embryo transfer. (FTET). Although these\u0000 protocols have functioned well for several years, attention has recently been directed\u0000 to the effect of estrus expression and estradiol concentrations during pre-ovulatory\u0000 follicle growth on embryonic growth and pregnancy. The experiments reviewed in this\u0000 document demonstrate that oestrus expression is positively associated with high\u0000 pregnancy rates and reduced pregnancy losses in recipients receiving frozen / thawed\u0000 bovine embryos produced in vitro and in vivo.","PeriodicalId":36778,"journal":{"name":"Spermova","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45941286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Menchaca, R. Núñez–Olivera, C. García-Pintos, F. Fabini, J. J. de la Mata, E. Huguenine, G. Bó
The objective of this work was to carry out a bibliographic search of all the programs with prolonged proestrus in the fertility of bovine cattle dedicated to meat production. The use of artificial insemination at fixed time (IATF) in cattle has not stopped growing in the countries of the region during the last 20 years, demonstrating that it is a technology that is here to stay. Its adoption curve is in a stage of maturity, having first been adopted by the most innovative and today it is already used by more pragmatic or conservative producers. Therefore, in this review we will emphasize the protocols that we have worked the most in recent years and with which high pregnancy rates have been achieved.
{"title":"is it possible to improve fertility with prolonged proestrus protocols?\u0000 physiological bases, results and new perspectives","authors":"A. Menchaca, R. Núñez–Olivera, C. García-Pintos, F. Fabini, J. J. de la Mata, E. Huguenine, G. Bó","doi":"10.18548/aspe/0010.18","DOIUrl":"https://doi.org/10.18548/aspe/0010.18","url":null,"abstract":"The objective of this work was to carry out a bibliographic search of all the\u0000 programs with prolonged proestrus in the fertility of bovine cattle dedicated to meat\u0000 production. The use of artificial insemination at fixed time (IATF) in cattle has not\u0000 stopped growing in the countries of the region during the last 20 years, demonstrating\u0000 that it is a technology that is here to stay. Its adoption curve is in a stage of\u0000 maturity, having first been adopted by the most innovative and today it is already used\u0000 by more pragmatic or conservative producers. Therefore, in this review we will emphasize\u0000 the protocols that we have worked the most in recent years and with which high pregnancy\u0000 rates have been achieved.","PeriodicalId":36778,"journal":{"name":"Spermova","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49501989","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cows that do not become pregnant during early lactation after successive inseminations are usually classified as repeat-breeder cows. Furthermore, heat stress has a pronounced deleterious effect on fertility in dairy herds throughout the world, especially in hot and humid summer months in tropical and subtropical areas. Studies describes the detrimental effect of heat stress on reproduction, with emphasis on carry over effects of heat stress on oocyte quality, embryo development and P/AI. Additionally, lower fertilization rate is also an important characteristic associated with repeatbreeder cows. In repeat-breeder cows, decreased fertility has been related to a deleterious effect on oocyte quality. Thus, the fertility problems observed in repeat-breeder and heat stress cows may be related to poor oocyte quality associated with a metabolic status. Studies support thar embryo transfer can be a practical and effective solution to achieve pregnancy in repeat-breeder and heatstressed dairy cows (with reduced oocyte quality and fertility to insemination).
{"title":"USE OF REPRODUCTIVE BIOTECHNOLOGIES TO IMPROVE THE FERTILITY OF REPEAT-BREEDER AND\u0000 HEAT-STRESSED DAIRY COWS","authors":"P. Baruselli, B. Catussi, L. Angelo de Abreu","doi":"10.18548/aspe/0010.16","DOIUrl":"https://doi.org/10.18548/aspe/0010.16","url":null,"abstract":"Cows that do not become pregnant during early lactation after successive\u0000 inseminations are usually classified as repeat-breeder cows. Furthermore, heat stress\u0000 has a pronounced deleterious effect on fertility in dairy herds throughout the world,\u0000 especially in hot and humid summer months in tropical and subtropical areas. Studies\u0000 describes the detrimental effect of heat stress on reproduction, with emphasis on carry\u0000 over effects of heat stress on oocyte quality, embryo development and P/AI.\u0000 Additionally, lower fertilization rate is also an important characteristic associated\u0000 with repeatbreeder cows. In repeat-breeder cows, decreased fertility has been related to\u0000 a deleterious effect on oocyte quality. Thus, the fertility problems observed in\u0000 repeat-breeder and heat stress cows may be related to poor oocyte quality associated\u0000 with a metabolic status. Studies support thar embryo transfer can be a practical and\u0000 effective solution to achieve pregnancy in repeat-breeder and heatstressed dairy cows\u0000 (with reduced oocyte quality and fertility to insemination).","PeriodicalId":36778,"journal":{"name":"Spermova","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43103247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study evaluated the effect of oxygen supplementation on the hatchability of fertile eggs of the Creole hen at 2718 meter above sea level. The experiment was carried out with 1408 hatching eggs obtained at age different of the breeders (25, 30, 34 and 38 wks.). Eggs were assigned to four incubators with different periods of oxygen supplementation: treatment without oxygen supplementation (SS) and oxygen supplementations at week 1, week 3, and weeks 1 and 3. Body weight, hematocrit, and hemoglobin were determined of embryos of 18 days incubation and newborn chicks. Hatching percentage was calculated based on the number of fertile eggs. Early and late embryonic mortality was determined. From the fertile eggs supplemented with oxygen during the first and third weeks, a higher percentage of hatched chicks (82.60%) and lower embryonic mortality were obtained. In the group SS, a low percentage of hatched chicks (28.32%) and high embryonic mortality were found. Oxygen supplementation to fertile creole hen eggs under hypobaric conditions in the Cajamarca valley did not increase hemoglobin concentration or improve body weight of hatched chicken.
{"title":"Oxygen supplementation in the incubation of creole hen fertile egg","authors":"M. Paredes, Irma Bustamante","doi":"10.18548/aspe/0010.07","DOIUrl":"https://doi.org/10.18548/aspe/0010.07","url":null,"abstract":"This study evaluated the effect of oxygen supplementation on the hatchability of\u0000 fertile eggs of the Creole hen at 2718 meter above sea level. The experiment was carried\u0000 out with 1408 hatching eggs obtained at age different of the breeders (25, 30, 34 and 38\u0000 wks.). Eggs were assigned to four incubators with different periods of oxygen\u0000 supplementation: treatment without oxygen supplementation (SS) and oxygen\u0000 supplementations at week 1, week 3, and weeks 1 and 3. Body weight, hematocrit, and\u0000 hemoglobin were determined of embryos of 18 days incubation and newborn chicks. Hatching\u0000 percentage was calculated based on the number of fertile eggs. Early and late embryonic\u0000 mortality was determined. From the fertile eggs supplemented with oxygen during the\u0000 first and third weeks, a higher percentage of hatched chicks (82.60%) and lower\u0000 embryonic mortality were obtained. In the group SS, a low percentage of hatched chicks\u0000 (28.32%) and high embryonic mortality were found. Oxygen supplementation to fertile\u0000 creole hen eggs under hypobaric conditions in the Cajamarca valley did not increase\u0000 hemoglobin concentration or improve body weight of hatched chicken.","PeriodicalId":36778,"journal":{"name":"Spermova","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46352766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Proceedings del Primer Simposio Internacional de Reproducción Animal, organizado por el Instituto de Reproducción Animal del Ecuador (IRAE), realizado en el Centro de Convenciones de Guayaquil, 18 y 19 de marzo de 2022.
{"title":"Proceedings del Primer Simposio Internacional de Reproducción Animal","authors":"","doi":"10.18548/aspe/0010.22","DOIUrl":"https://doi.org/10.18548/aspe/0010.22","url":null,"abstract":"Proceedings del Primer Simposio Internacional de Reproducción Animal, organizado\u0000 por el Instituto de Reproducción Animal del Ecuador (IRAE), realizado en el Centro de\u0000 Convenciones de Guayaquil, 18 y 19 de marzo de 2022.","PeriodicalId":36778,"journal":{"name":"Spermova","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42727118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fixed–time artificial insemination (FTAI) in cattle has had a marked growth in South American countries in the last two decades, mainly based in the use of pharmacological treatments with estradiol and progesterone. To improve the pregnancy rate obtained with this technology, the focus has recently been on other aspects of the hormonal protocols that had not been considered previously. The most novel approaches propose studying preovulatory strategies to improve postovulatory conditions to improve pregnancy outcomes. In this paper we review the main results obtained by extending the proestrus length (i.e., the interval from progesterone removal to insemination). The results show that these new approaches allow an improvement in pregnancy rate, which deserves to be taken into account to be included in the implementation of FTAI programs.
{"title":"Update on protocols for fixe-timed artificial insemination in sheep","authors":"F. Cuadro, P. dos Santos-Neto, A. Menchaca","doi":"10.18548/aspe/0010.20","DOIUrl":"https://doi.org/10.18548/aspe/0010.20","url":null,"abstract":"Fixed–time artificial insemination (FTAI) in cattle has had a marked growth in\u0000 South American countries in the last two decades, mainly based in the use of\u0000 pharmacological treatments with estradiol and progesterone. To improve the pregnancy\u0000 rate obtained with this technology, the focus has recently been on other aspects of the\u0000 hormonal protocols that had not been considered previously. The most novel approaches\u0000 propose studying preovulatory strategies to improve postovulatory conditions to improve\u0000 pregnancy outcomes. In this paper we review the main results obtained by extending the\u0000 proestrus length (i.e., the interval from progesterone removal to insemination). The\u0000 results show that these new approaches allow an improvement in pregnancy rate, which\u0000 deserves to be taken into account to be included in the implementation of FTAI\u0000 programs.","PeriodicalId":36778,"journal":{"name":"Spermova","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47737204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Eliana Vilca, Miluska Navarrete, Gilberto Santillán, A. Chavez, Francisco Santos
The aim of this work was to describe macroscopically and microscopically the ovaries of alpacas during the fetal stage. We worked with 18 female fetuses collected at the Huancavelica Municipal Slaughterhouse, from alpacas destined for human consumption. The process and analysis of the collected samples was performed at the Faculty of Veterinary Medicine - UNMSM, in Lima, Peru. Fetal age was calculated by measuring the biparietal diameter and divided into three groups: Group I (60 - 150 days), Group II (151 - 239 days) and Group III (240 - 335 days). The weight of the ovaries was 0.02 ± 0.01, 0.03 ± 0.01 and 0.03 ± 0.01 grams in the first, second and third group, respectively. The ovaries were paired, oval-shaped, with a smooth, cream surface, located in the sublumbar region at the level of the 6th and 7th lumbar vertebrae. The cortex and medulla were visible from the third month. Microscopically, in Group I, we observed oogonium, the distinction between cortex and medulla, unilaminar primary follicles, atresia and segmentation of the germ cells. In Group II, we observed preantral primary follicles. In Group III, we observed preovulatory follicles. We concluded that, from day 68 of the fetal stage of the alpaca, ovaries have macroscopic characteristics similar to those of an adult alpaca. Microscopically, they presented ovogonia, primordial follicles, unilaminar primary follicles, preantral follicles, preovulatory follicle, as well as the degeneration of the germ cells.
{"title":"MACROSCOPIC AND MICROSCOPIC DESCRIPTION OF ALPACA (Vicugna pacos) OVARIES DURING\u0000 THE FETAL STAGE","authors":"Eliana Vilca, Miluska Navarrete, Gilberto Santillán, A. Chavez, Francisco Santos","doi":"10.18548/aspe/0010.01","DOIUrl":"https://doi.org/10.18548/aspe/0010.01","url":null,"abstract":"The aim of this work was to describe macroscopically and microscopically the\u0000 ovaries of alpacas during the fetal stage. We worked with 18 female fetuses collected at\u0000 the Huancavelica Municipal Slaughterhouse, from alpacas destined for human consumption.\u0000 The process and analysis of the collected samples was performed at the Faculty of\u0000 Veterinary Medicine - UNMSM, in Lima, Peru. Fetal age was calculated by measuring the\u0000 biparietal diameter and divided into three groups: Group I (60 - 150 days), Group II\u0000 (151 - 239 days) and Group III (240 - 335 days). The weight of the ovaries was 0.02 ±\u0000 0.01, 0.03 ± 0.01 and 0.03 ± 0.01 grams in the first, second and third group,\u0000 respectively. The ovaries were paired, oval-shaped, with a smooth, cream surface,\u0000 located in the sublumbar region at the level of the 6th and 7th lumbar vertebrae. The\u0000 cortex and medulla were visible from the third month. Microscopically, in Group I, we\u0000 observed oogonium, the distinction between cortex and medulla, unilaminar primary\u0000 follicles, atresia and segmentation of the germ cells. In Group II, we observed\u0000 preantral primary follicles. In Group III, we observed preovulatory follicles. We\u0000 concluded that, from day 68 of the fetal stage of the alpaca, ovaries have macroscopic\u0000 characteristics similar to those of an adult alpaca. Microscopically, they presented\u0000 ovogonia, primordial follicles, unilaminar primary follicles, preantral follicles,\u0000 preovulatory follicle, as well as the degeneration of the germ cells.","PeriodicalId":36778,"journal":{"name":"Spermova","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44972912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
W. Garcia, Veronica Macedo, Elizabeth Mendoza, Nubia Catacora, Julio Malaga
The objective of this study was to determine the effect of glycerol (GL), dimethyl sulfoxide (DMSO) and dimethylformamide (DMF) at temperatures of 5 °C and 16 °C of equilibrium on sperm quality, after cryopreservation. 6 males were used in the semen collection, motility parameters were evaluated with the CASA system, viability, acrosomal integrity and mitochondrial activity by flow cytometry in fresh and thawed semen. We collected 30 ejaculates of which 10 were discarded for not fulfilling (volume ≥ 1 ml and total motility ≥ 60 %), the 20 ejaculates were mesclo in a tube to form pool carrying out the assessment of the initial quality of fresh semen, obtaining a total motility (MT) 61,6 ± 3,4%, progressive motility (MP) 51,7 ± 3,7%, viability 78,1 ± 9.1%, mitochondrial activity (MA) 77,4 ± 7,7 and acrosomal integrity 88,9 ± 11,5%. After cryopreservation no equilibrium temperature effect was observed, independently of cryoprotectant in the parameters of seminal quality. Cryoprotective effect (P≤ 0.05) was observed, presenting superior values in the sperm conserved in GL with respect to the rest of cryoprotectants, with significant differences (P ≤ 0,05) in MT, MP, viability and AM and without significant differences in acrosomal integrity. The equilibrium temperature of 16 °C was effective for cryopreservation of alpaca sperm. In addition, the 5% GL preserved better the functional characteristics of sperm compared to 7% (DMF and DMSO).
{"title":"Effect of cryoprotectant type and equilibrium temperature on cryopreservation of\u0000 alpaca sperm (Vicugna pacos)","authors":"W. Garcia, Veronica Macedo, Elizabeth Mendoza, Nubia Catacora, Julio Malaga","doi":"10.18548/aspe/0010.03","DOIUrl":"https://doi.org/10.18548/aspe/0010.03","url":null,"abstract":"The objective of this study was to determine the effect of glycerol (GL), dimethyl\u0000 sulfoxide (DMSO) and dimethylformamide (DMF) at temperatures of 5 °C and 16 °C of\u0000 equilibrium on sperm quality, after cryopreservation. 6 males were used in the semen\u0000 collection, motility parameters were evaluated with the CASA system, viability,\u0000 acrosomal integrity and mitochondrial activity by flow cytometry in fresh and thawed\u0000 semen. We collected 30 ejaculates of which 10 were discarded for not fulfilling (volume\u0000 ≥ 1 ml and total motility ≥ 60 %), the 20 ejaculates were mesclo in a tube to form pool\u0000 carrying out the assessment of the initial quality of fresh semen, obtaining a total\u0000 motility (MT) 61,6 ± 3,4%, progressive motility (MP) 51,7 ± 3,7%, viability 78,1 ± 9.1%,\u0000 mitochondrial activity (MA) 77,4 ± 7,7 and acrosomal integrity 88,9 ± 11,5%. After\u0000 cryopreservation no equilibrium temperature effect was observed, independently of\u0000 cryoprotectant in the parameters of seminal quality. Cryoprotective effect (P≤ 0.05) was\u0000 observed, presenting superior values in the sperm conserved in GL with respect to the\u0000 rest of cryoprotectants, with significant differences (P ≤ 0,05) in MT, MP, viability\u0000 and AM and without significant differences in acrosomal integrity. The equilibrium\u0000 temperature of 16 °C was effective for cryopreservation of alpaca sperm. In addition,\u0000 the 5% GL preserved better the functional characteristics of sperm compared to 7% (DMF\u0000 and DMSO).","PeriodicalId":36778,"journal":{"name":"Spermova","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45185726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Mapletoft, G. Bó, P. Baruselli, A. Menchaca, R. Sartori
As our understanding of ovarian function in cattle has improved, our ability to control it has also increased. Luteal function in cattle has been studied in detail, and prostaglandin F2α has been used for several years for elective induction of luteal regression. More recently, follicular wave dynamics have been studied and protocols have been designed to induce follicular wave emergence and ovulation, and the need to detect oestrus has even been eliminated. The addition of progesterone, estradiol, GnRH and equine chorionic gonadotropin (eCG) releasing devices has provided opportunities for fixed-time AI (IATF) and possibilities for achieving higher pregnancy rates. In embryo transfer programs, these same treatments have eliminated the need to detect oestrus, allowing fixed-time embryo transfer (TETF) and the initiation of superstimulatory treatments regardless of the day of the estrous cycle. Taken together, the new protocols have facilitated the application of assisted reproductive technologies, and this is especially true in South America. Over the past 20 years, the use of AI in South America has increased, due in large part to the use of the IATF. The use of the IATF has been multiplied by more than 10 times in Brazil, with more than 11 million treatments in 2016, which represents 85% of all AI. Similar trends are occurring in Argentina and Uruguay. In vivo embryo production produced by superovulation (DIV) has remained relatively stable over the years, but in vitro embryo production (PIV) has increased dramatically in the last 10 to 15 years, especially in Brazil, where More than 300,000 PIV embryos were produced in 2010. Worldwide, over 990,000 bovine PIV embryos were produced in 2017, of which more than% were produced in South America. The use of assisted reproductive technologies has facilitated the spread of genetic improvements and increased reproductive performance; These practices are spreading to many South American countries.
{"title":"EVOLUTION OF KNOWLEDGE ABOUT OVARIAN PHYSIOLOGY AND ITS CONTRIBUTION TO THE\u0000 APPLICATION OF REPRODUCTIVE BIOTECHNOLOGIES IN SOUTH AMERICA","authors":"R. Mapletoft, G. Bó, P. Baruselli, A. Menchaca, R. Sartori","doi":"10.18548/aspe/0010.19","DOIUrl":"https://doi.org/10.18548/aspe/0010.19","url":null,"abstract":"As our understanding of ovarian function in cattle has improved, our ability to\u0000 control it has also increased. Luteal function in cattle has been studied in detail, and\u0000 prostaglandin F2α has been used for several years for elective induction of luteal\u0000 regression. More recently, follicular wave dynamics have been studied and protocols have\u0000 been designed to induce follicular wave emergence and ovulation, and the need to detect\u0000 oestrus has even been eliminated. The addition of progesterone, estradiol, GnRH and\u0000 equine chorionic gonadotropin (eCG) releasing devices has provided opportunities for\u0000 fixed-time AI (IATF) and possibilities for achieving higher pregnancy rates. In embryo\u0000 transfer programs, these same treatments have eliminated the need to detect oestrus,\u0000 allowing fixed-time embryo transfer (TETF) and the initiation of superstimulatory\u0000 treatments regardless of the day of the estrous cycle. Taken together, the new protocols\u0000 have facilitated the application of assisted reproductive technologies, and this is\u0000 especially true in South America. Over the past 20 years, the use of AI in South America\u0000 has increased, due in large part to the use of the IATF. The use of the IATF has been\u0000 multiplied by more than 10 times in Brazil, with more than 11 million treatments in\u0000 2016, which represents 85% of all AI. Similar trends are occurring in Argentina and\u0000 Uruguay. In vivo embryo production produced by superovulation (DIV) has remained\u0000 relatively stable over the years, but in vitro embryo production (PIV) has increased\u0000 dramatically in the last 10 to 15 years, especially in Brazil, where More than 300,000\u0000 PIV embryos were produced in 2010. Worldwide, over 990,000 bovine PIV embryos were\u0000 produced in 2017, of which more than% were produced in South America. The use of\u0000 assisted reproductive technologies has facilitated the spread of genetic improvements\u0000 and increased reproductive performance; These practices are spreading to many South\u0000 American countries.","PeriodicalId":36778,"journal":{"name":"Spermova","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48214767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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