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1.
Theriogenology ; 218: 200-207, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38335707

RESUMO

Members of the Equus genus exhibit a fascinating capacity for hybridization, giving rise to healthy offspring. Mules, resulting from the mating of a mare with a jack, represent the most prevalent equid hybrid, serving diverse roles in our society. While in vitro embryo production, particularly through Intracytoplasmic Sperm Injection (ICSI), has rapidly gained significance in domestic horses, the in vitro production in other equids remains largely unexplored. Utilizing donkey sperm for fertilizing horse oocytes not only addresses this gap but also provides an opportunity to investigate donkey sperm's fertilization capability in vitro to further improve donkey ICSI. In this work, we initially studied the localization of donkey sperm Phospholipase C zeta (PLCζ) and assessed the sperm's capacity to induce pronuclear formation and maternal SMARCA4 recruitment upon injection into pig oocytes through ICSI. Subsequently, we investigated the injection of donkey sperm into horse oocytes, evaluating in vitro production up to the blastocyst stage using sperm from different jacks, including frozen and refrigerated samples. Distinct patterns of PLCζ localization were observed for donkey sperm cells compared to their horse counterparts. Additionally, donkey sperm exhibits a reduced ability to induce porcine oocyte activation. However, when injected into horse oocytes, donkey sperm demonstrated sufficient capability to induce oocyte activation as no discernible differences in cleavage or blastocyst rates are observed between in vitro produced mules and horse ICSI embryos. Our study not only delineates PLCζ localization in donkey sperm but also suggests potential differences in the ability to induce oocyte activation in pigs compared to horses while observing no distinctions in pronuclear recruitment of SMARCA4. Interestingly, donkey sperm remains sufficiently capable of inducing horse oocyte activation for in vitro mule blastocyst production.


Assuntos
Equidae , Injeções de Esperma Intracitoplásmicas , Cavalos , Masculino , Animais , Feminino , Suínos , Injeções de Esperma Intracitoplásmicas/veterinária , Sêmen , Oócitos/fisiologia , Espermatozoides/fisiologia , Desenvolvimento Embrionário/fisiologia
2.
Theriogenology ; 195: 199-208, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36356490

RESUMO

Equus members exhibit very divergent karyotype, genetic plasticity, and significant differences in their reproductive physiology. Despite the fact that somatic cell nuclear transfer and intracytoplasmic sperm injection (ICSI) has gained relevance in the last few years in horses, few reports have been published exploring ovum pick up (OPU) and in vitro maturation (IVM) of cumulus-oocyte complexes (COCs) in donkeys. Yet, some donkey species and breeds are considered endangered, and these assisted-reproductive technologies could help to preserve the genetic of valuable individuals. In this study, we tested the hypothesis that supplementation with jenny preovulatory follicular fluid (PFF) during IVM could improve oocyte developmental competence in the donkey. For this, in vitro nuclear maturation rates, cumulus cell expansion, and embryo development after ICSI of donkey COCs matured in culture media supplemented with fetal bovine serum (FBS) or donkey PFF, with a known metabolomic profile, were assessed. Time-lapse imagining was performed after ICSI of horse and donkey oocytes. Eight OPU sessions were done in five jennies with an average recovery rate of 69.2% (n = 45 COCs). Although lower cumulus cells expansion was observed in oocytes of PFF group (P = 0.0010), no significant differences were described in nuclear maturation rates and preimplantation embryo development between groups. Donkey ICSI embryos showed similar morphokinetics to horse ICSI embryos. Our study shows that supplementing IVM media with FBS or donkey PFF supports nuclear maturation and early preimplantation embryo development after ICSI in donkeys. To our knowledge, the present study is the first report of ICSI, time-lapse imaging and in vitro blastocyst production in donkey.


Assuntos
Líquido Folicular , Técnicas de Maturação in Vitro de Oócitos , Masculino , Gravidez , Animais , Feminino , Cavalos , Técnicas de Maturação in Vitro de Oócitos/veterinária , Equidae , Imagem com Lapso de Tempo/veterinária , Injeções de Esperma Intracitoplásmicas/veterinária , Sêmen
3.
Rev. bras. reprod. anim ; 47(2): 212-219, abr.-jun. 2023. graf, tab
Artigo em Inglês | VETINDEX | ID: biblio-1435291

RESUMO

At least 30-40% of stallions in commercial breeding programs are moderately fertile and 8-12% are subfertile (0.5-3% with severe subfertility). From the total reported cases of the subfertility, in 2-20% of the stallions the cause is unknown or was not established. The objective of this work is to present the concept of subfertile stallion based on the current state of knowledge and advanced molecular diagnostic technologies. Low pregnancy rates have been reported in stallions with normal semen quality after conventional evaluation. Acrosome reaction (AR) is necessary for natural fertilization and impaired acrosome reaction (IAR) leads to subfertility or infertility in horses, however, AR test is not included in routine semen analysis. Genome-wide association study identified FKBP6 as a strong candidate gene responsible for this failure. The gene encodes for FK506 binding protein 6 (FKBP6) which is involved in sperm development and functions. We could conclude that the evaluation of the acrosomal status is essential in cases of stallions with good motility, concentration, morphology and viability but unexplained (idiopathic) subfertility or infertility. It is important to highlight the recent increase in reports of fertility problems in stallions related to disorders of genetic origin.(AU)


Assuntos
Animais , Masculino , Análise do Sêmen/métodos , Cavalos/fisiologia , Coeficiente de Natalidade , Reação Acrossômica/fisiologia
4.
Rev. bras. reprod. anim ; 47(2): 249-256, abr.-jun. 2023. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1435327

RESUMO

Mares, which make up 90% of animals requiring reproductive assistance in commercial equine production systems, are subjected to strong breeding and reproductive efficiency pressure throughout their lives, but the effects of aging on overall and reproductive systems in particular; it often means that we are forcing the natural homeostasis mechanisms under pressure over time. The objective of this brief communication is to summarize some concepts related to the role and importance of equine endometrium, particularly in old mares, the most challenged category to achieve productive and efficiency goals established by humans. Endometritis is one of the most frequent and recurrent pathologies in equine gynecology and is responsible for enormous economic losses in the industry. Alterations of the microbiota, molecular signals and uterine endocrine microenvironment can lead to infertility, but degenerative phenomena associated with age and parity can lead to endometriosis altering maternal recognition of pregnancy and pregnancy maintenance. Maintaining horses in an adequate nutrition status and environment is essential to achieve pregnancy but also to obtain healthy offspring.(AU)


Assuntos
Animais , Feminino , Endométrio/anatomia & histologia , Cavalos/anatomia & histologia , Envelhecimento/fisiologia , Homeostase
5.
Braz. j. vet. res. anim. sci ; 58(n.esp): e174301, 2021. tab
Artigo em Inglês | VETINDEX | ID: vti-764841

RESUMO

Developing effective cooled semen protocols is essential to increase pregnancy rates and reproductive efficiency in donkeys. This study aimed to evaluate the effect on sperm kinetic parameters and membrane integrity in cooled donkey semen diluted with defined milk proteins extender with 1% or 2% of egg yolk and the removal of seminal plasma. Twenty-four ejaculates from six jackasses were collected. Each ejaculate was divided into four aliquots that were diluted in extender with 1% (EY1) or 2% (EY2) egg yolk. One sample from each group was centrifuged, seminal plasma was removed (CEY1, CEY2 groups, respectively), and the samples were then refrigerated at 5 °C for 24 h. Fresh and cooled semen samples were assessed for sperm motility, morphology, and plasma membrane integrity. Total motility, progressive motility, sperm kinetic parameters, or live sperm cells were not statistically different when semen was cooled with an extender supplemented with 1% or 2% of egg yolk. Seminal plasma removal does not affect total motility or sperm kinetic parameters. However, progressive motility decreased (P<0.05) when semen was extended with 2% of egg yolk and seminal plasma was removed. Membrane integrity was affected (P<0.05) in centrifuged samples. In conclusion, the obtained results suggest that there is no difference in sperm kinetics and membrane integrity when 1% or 2% of egg yolk was added to the Equiplus extender. Also, the removal of seminal plasma by centrifugation did not have any beneficial effect on cooled donkey semen. Further studies are needed to relate these results with in vivo fertility tests with cooled donkey semen.(AU)


O desenvolvimento de protocolos de sêmen resfriado eficazes é essencial para aumentar as taxas de prenhez e eficiência reprodutiva em jumentos. O objetivo desse estudo foi avaliar o efeito do diluente à base de proteínas do leite com 1 ou 2% de gema de ovo sobre os parâmetros cinéticos do sêmen e integridade da membrana em sêmen resfriado de jumento, com ou sem a remoção do plasma seminal. Vinte e quatro ejaculados de seis jumentos foram coletados. Cada ejaculado foi dividido em quatro alíquotas e diluído em diluente com 1% (EY1) ou 2% (EY2) de gema de ovo. Uma amostra por grupo foi centrifugada e o plasma seminal removido (grupos CEY1 e CEY2, respectivamente). Os pellets foram novamente ressuspendidos nas mesmas concentrações e diluentes. Em seguida, as quatro alíquotas foram refrigeradas a 5°C por 24 horas. Amostras de sêmen fresco e refrigerado foram avaliadas quanto à motilidade espermática e integridade da membrana plasmática. Motilidade total, motilidade progressiva, parâmetros de cinética espermática ou células espermáticas vivas não apresentaram diferença significativa quando o sêmen foi resfriado com diluente suplementado com 1% ou 2% de gema de ovo. A remoção do plasma seminal não afetou a motilidade total ou os parâmetros de cinética espermática; entretanto, a motilidade progressiva diminuiu (P<0,05) quando o sêmen foi diluído com 2% de gema de ovo e o plasma seminal removido. Nas amostras centrifugadas, a integridade da membrana foi afetada (P<0,05). Em conclusão, os resultados sugerem que não há diferença na cinética espermática e na integridade da membrana quando 1% ou 2% de gema de ovo são adicionados ao diluente Equiplus e a remoção do plasma seminal por centrifugação não teve nenhum efeito benéfico no resfriamento de sêmen de jumento. Mais estudos são necessários para relacionar esses resultados com testes de fertilidade in vivo com sêmen resfriado em jumentos.(AU)


Assuntos
Animais , Plasma , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Criopreservação , Equidae , Gema de Ovo , Sêmen , Proteínas
6.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 58(n.esp): e174301, 2021. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1348265

RESUMO

Developing effective cooled semen protocols is essential to increase pregnancy rates and reproductive efficiency in donkeys. This study aimed to evaluate the effect on sperm kinetic parameters and membrane integrity in cooled donkey semen diluted with defined milk proteins extender with 1% or 2% of egg yolk and the removal of seminal plasma. Twenty-four ejaculates from six jackasses were collected. Each ejaculate was divided into four aliquots that were diluted in extender with 1% (EY1) or 2% (EY2) egg yolk. One sample from each group was centrifuged, seminal plasma was removed (CEY1, CEY2 groups, respectively), and the samples were then refrigerated at 5 °C for 24 h. Fresh and cooled semen samples were assessed for sperm motility, morphology, and plasma membrane integrity. Total motility, progressive motility, sperm kinetic parameters, or live sperm cells were not statistically different when semen was cooled with an extender supplemented with 1% or 2% of egg yolk. Seminal plasma removal does not affect total motility or sperm kinetic parameters. However, progressive motility decreased (P<0.05) when semen was extended with 2% of egg yolk and seminal plasma was removed. Membrane integrity was affected (P<0.05) in centrifuged samples. In conclusion, the obtained results suggest that there is no difference in sperm kinetics and membrane integrity when 1% or 2% of egg yolk was added to the Equiplus extender. Also, the removal of seminal plasma by centrifugation did not have any beneficial effect on cooled donkey semen. Further studies are needed to relate these results with in vivo fertility tests with cooled donkey semen.(AU)


O desenvolvimento de protocolos de sêmen resfriado eficazes é essencial para aumentar as taxas de prenhez e eficiência reprodutiva em jumentos. O objetivo desse estudo foi avaliar o efeito do diluente à base de proteínas do leite com 1 ou 2% de gema de ovo sobre os parâmetros cinéticos do sêmen e integridade da membrana em sêmen resfriado de jumento, com ou sem a remoção do plasma seminal. Vinte e quatro ejaculados de seis jumentos foram coletados. Cada ejaculado foi dividido em quatro alíquotas e diluído em diluente com 1% (EY1) ou 2% (EY2) de gema de ovo. Uma amostra por grupo foi centrifugada e o plasma seminal removido (grupos CEY1 e CEY2, respectivamente). Os pellets foram novamente ressuspendidos nas mesmas concentrações e diluentes. Em seguida, as quatro alíquotas foram refrigeradas a 5°C por 24 horas. Amostras de sêmen fresco e refrigerado foram avaliadas quanto à motilidade espermática e integridade da membrana plasmática. Motilidade total, motilidade progressiva, parâmetros de cinética espermática ou células espermáticas vivas não apresentaram diferença significativa quando o sêmen foi resfriado com diluente suplementado com 1% ou 2% de gema de ovo. A remoção do plasma seminal não afetou a motilidade total ou os parâmetros de cinética espermática; entretanto, a motilidade progressiva diminuiu (P<0,05) quando o sêmen foi diluído com 2% de gema de ovo e o plasma seminal removido. Nas amostras centrifugadas, a integridade da membrana foi afetada (P<0,05). Em conclusão, os resultados sugerem que não há diferença na cinética espermática e na integridade da membrana quando 1% ou 2% de gema de ovo são adicionados ao diluente Equiplus e a remoção do plasma seminal por centrifugação não teve nenhum efeito benéfico no resfriamento de sêmen de jumento. Mais estudos são necessários para relacionar esses resultados com testes de fertilidade in vivo com sêmen resfriado em jumentos.(AU)


Assuntos
Animais , Plasma , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Criopreservação , Equidae , Gema de Ovo , Sêmen , Proteínas
7.
PLoS One ; 15(9): e0238948, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32915925

RESUMO

Several equids have gone extinct and many extant equids are currently considered vulnerable to critically endangered. This work aimed to evaluate whether domestic horse oocytes support preimplantation development of zebra embryos obtained by intracytoplasmic sperm injection (ICSI, zebroid) and cloning, and to study the Hippo signaling pathway during the lineage specification of trophectoderm cells and inner cell mass cells. We first showed that zebra and horse sperm cells induce porcine oocyte activation and recruit maternal SMARCA4 during pronuclear formation. SMARCA4 recruitment showed to be independent of the genetic background of the injected sperm. No differences were found in blastocyst rate of ICSI hybrid (zebra spermatozoon into horse egg) embryos relative to the homospecific horse control group. Interestingly, zebra cloned blastocyst rate was significantly higher at day 8. Moreover, most ICSI and cloned horse and zebra blastocysts showed a similar expression pattern of SOX2 and nuclear YAP1 with the majority of the nuclei positive for YAP1, and most SOX2+ nuclei negative for YAP1. Here we demonstrated that horse oocytes support zebra preimplantation development of both, ICSI and cloned embryos, without compromising development to blastocyst, blastocyst cell number neither the expression of SOX2 and YAP1. Our results support the use of domestic horse oocytes as a model to study in vitro zebra embryos on behalf of preservation of valuable genetic.


Assuntos
Desenvolvimento Embrionário , Equidae/embriologia , Equidae/genética , Cavalos/fisiologia , Oócitos/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Núcleo Celular/fisiologia , Clonagem de Organismos/veterinária , Citoplasma/fisiologia , Técnicas de Cultura Embrionária/veterinária , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Espécies em Perigo de Extinção , Equidae/metabolismo , Feminino , Perfilação da Expressão Gênica , Cavalos/genética , Técnicas In Vitro , Masculino , Técnicas de Transferência Nuclear/veterinária , Fatores de Transcrição SOXB1/genética , Injeções de Esperma Intracitoplásmicas/veterinária , Sus scrofa
8.
Anim Reprod Sci ; 221: 106582, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32889407

RESUMO

The successful use of assisted reproduction techniques (ART) depends in part on the sperm physiological status. Several sperm selection procedures have been applied to improve quality of sperm population when using the ART. There has previously been development of a Sperm Selection Assay (SSA) for humans which is based on the attraction of capacitated sperm by chemotaxis towards progesterone (P), resulting in an enriched sperm population with an optimal physiological status similar to capacitated spermatozoa, with these cells having very little DNA fragmentation and optimal concentrations of reactive oxygen species (ROS). In the present study, the aim was to adapt the SSA for frozen-thawed stallion semen samples and evaluate the functional status of those sperm selected using the SSA procedure, and to determine whether this enriched sperm population has a greater capacity to bind to the zona pellucida of cattle oocytes. There were experimental conditions developed to conduct the SSA with stallion sperm. Using these conditions, the indexes of induced acrosome reaction, protein tyrosine phosphorylation, mitochondrial membrane potential, mitochondrial and cytoplasmic reactive oxygen species, and number of sperm bound to the zona pellucida of cattle were greater when the sperm population was selected using the SSA. Consistently, the DNA fragmentation and phospholipase C zeta indexes were less for the selected sperm. In conclusion, stallion sperm selected using chemotaxis utilizing the SSA provides a sperm population of greater quality, which when used may improve the outcomes with use of the ART.


Assuntos
Criopreservação/veterinária , Cavalos/fisiologia , Preservação do Sêmen/veterinária , Interações Espermatozoide-Óvulo/fisiologia , Espermatozoides/fisiologia , Adaptação Fisiológica , Animais , Quimiotaxia , Congelamento , Masculino , Reprodutibilidade dos Testes
9.
Reproduction ; 159(4): 423-436, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31967971

RESUMO

Sperm chemotaxis may facilitate the finding of the oocyte. Only capacitated spermatozoa can orient their movement by chemotaxis, which as well as capacitation, is regulated in part by the cAMP-PKA pathway. Reactive oxygen species (ROS) are produced during sperm capacitation which is closely related to chemotaxis. Then, the ROS participation in the chemotactic signaling can be expected. Here we studied the role of ROS in the chemotaxis signaling of equine spermatozoa which produce high quantities of ROS because of their energy metabolism. The level of capacitated and chemotactic spermatozoa was increased with 0.1 and 0.2 mM hydrogen peroxide (H2O2), which was involved in the chemotactic signaling. By combining a concentration gradient of H2O2 with inhibitors/chelators of some of the signaling pathway elements, we showed that the activation of NOX (membrane NADPH oxidase) increases the intracellular ROS which activate the chemotaxis AMPc-PKA pathway. Our results provide evidence about the participation of ROS in the chemotactic signaling mediated by progesterone (P).


Assuntos
Quimiotaxia , Cavalos/metabolismo , Espécies Reativas de Oxigênio , Capacitação Espermática , Espermatozoides/metabolismo , Animais , Masculino
10.
Ciudad Autónoma de Buenos Aires; Argentina. Ministerio de Salud de la Nación. Dirección de Investigación en Salud; 2020. 1-30 p. graf.
Não convencional em Espanhol | ARGMSAL, BINACIS | ID: biblio-1379783

RESUMO

La APLV es una de las alergias de mayor prevalencia en niños de hasta un año de edad y puede generar severos trastornos en el desarrollo físico, cognitivo y psiquiátrico en niños que pueden persistir hasta la vida adulta debido a desequilibrios que pueden no ser cubiertos por las dietas sustitutivas comerciales. En Argentina la prevalencia se incrementó de 0,2% a 1,2% entre 2004 y 2014. La composición de la leche de burra posee mayor similitud a la leche humana en comparación con la leche de otras especies domésticas y se ha comprobado su adecuada calidad nutricional, tolerabilidad y efectos clínicos benéficos en niños con APLV. La producción, evaluación de la calidad de leche de burra y ensayos clínicos en niños debería ser objeto de estudio y desarrollo para que los niños con APLV puedan acceder a productos hipoalergénicos naturales de calidad nutricional adecuada y de mercado nacional para su consumo. El objetivo de esta investigación fue caracterizar la composición química, microbiológica y sanitaria de la leche de burras nativas de Argentina. Se utilizaron 5 burras que fueron ordeñadas a partir de la tercera semana postparto dos días a la semana hasta el mes 9 pos parto. De cada ordeño se tomó una muestra y se refrigeró a 4°C por un máximo de 72 hs previo a su envío para análisis composicional, microbiológico y sanitario al laboratorio LabVima (Villa María). Los resultados demostraron que el modelo de Wood pudo determinar la forma de la curva de lactancia utilizando los datos de toda la lactación de las burras incluidas en el estudio (R2= 0.91), alcanzando el pico de producción de leche en el día 134. Las curvas individuales demostraron una amplia variación. La producción de materia grasa y la lactosa aumentaron de manera creciente durante el periodo de lactancia estudiado alcanzando el valor máximo de 0.22 g/100ml y de 6.47 g/100ml respectivamente al día 330. La proteína disminuyó gradualmente durante toda la lactancia, alcanzando el valor estimado de 2.29 ± 0.21g/100ml al comienzo de la lactancia. El recuento de células somáticas alcanzó un máximo de 11 (cél/ml x1000) el día 100. En conclusión los parámetros composicionales, microbiológicos y sanitarios de la leche de burras nativas de Argentina son similares a los reportados de burras de razas europeas y por ende aceptables para consumo por parte de niños con APLV


Assuntos
Pesquisa Qualitativa
11.
J Equine Vet Sci ; 78: 123-126, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31203975

RESUMO

In the present study, 2.228 cycles of 180 Polo Argentino donor mares from an embryo transfer program in Argentina were examined to evaluate the effects of: (1) Interval from Prostaglandin F2alpha analog treatment to ovulation (ITO) on embryo recovery rate (ERR); (2) ITO on number of embryos per flushing (EPF); (3) ITO on multiple ovulation (MO) rate; (4) ITO from donor mare on pregnancy rate (PR) in recipient mares. Mares were inseminated with fresh semen from 31 fertile stallions in the induced estrus. Embryo flushing was performed 7-8 days postovulation. Following embryo flushing, donor mares were treated with prostaglandin F2alpha analog (cloprostenol 250 µg). The ERR increased along with the ITO (P = .01), with the lowest ERR (30.7%) for mares with an ITO of <4 days, and the highest (78.3%) in mares with an ITO of 10 days. The ITO from the donor mare in which the embryo was recovered did not have a significant effect on PR: ITO <6, 6 to 10, and >10 days were 74.6, 81.4, and 77.3%, respectively. The number of EPF and MO rate increased gradually along with the ITO (P < .05). In conclusion, the results of this study indicated that the ITO is positively correlated with the embryo recovery and the multiple ovulation rate.


Assuntos
Dinoprosta , Ovulação , Animais , Argentina , Transferência Embrionária/veterinária , Feminino , Cavalos , Masculino , Gravidez , Reprodução
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