RESUMO
Heat stress reduces the reproductive capacity of bulls raised in tropical climate. However, the reestablishment of scrotal thermoregulation and the dynamics of sperm defects emergence after stress are not completely known in buffaloes. Thus, the study aimed to evaluate the effect of short-term heat stress over scrotal thermoregulation and sperm attributes, relating them to spermatogenesis stages. Five buffalo bulls went through scrotal insulation during 48 h (from day 0 to day 2). Semen samples were collected every 7 days (from day -7 to day 49) and analyzed about the progressive motility, viability, and sperm morphology. Heat stress significantly destabilized scrotal thermoregulation (P < 0.001). Scrotal temperature was from 4.2 to 6.3 °C lower than the core body temperature, except on insulation days (P < 0.001), and returned to the basal condition five days after the removal of the stressing stimulus. More significant deleterious effects were observed in sperm morphology than in cell concentration, motility, and viability. The chronology of morphologic defects expression demonstrated tail defects (days 7-14), cytoplasmic droplets (days 14-28), and head defects (day 28), returning to pre-insulation condition 35 days after the thermal challenge. Thus, hyperthermia harmed more intensely spermatozoa in epididymal transit, elongated spermatids, and secondary spermatocytes. It is concluded that water buffalo bulls present a peculiar manifestation of sperm morphology after short-term stress, indicating an important difference related to the bovine species. Therefore, during the andrological evaluation of buffalo bulls, it is necessary to avoid the allometric extrapolation between these species.
Assuntos
Búfalos/fisiologia , Resposta ao Choque Térmico , Escroto/fisiologia , Espermatozoides/anormalidades , Espermatozoides/fisiologia , Animais , Regulação da Temperatura Corporal , Transtornos de Estresse por Calor/fisiopatologia , Transtornos de Estresse por Calor/veterinária , Umidade , Masculino , Contagem de Espermatozoides , Motilidade dos Espermatozoides , TemperaturaRESUMO
Sex selection through sperm sorting offers advantages in regards selection pressure in high-producing livestock. However, the sex-sorting process results in sperm membrane and DNA damage that ultimately decrease fertility. We hypothesized that given the role of protamines in DNA packaging, protamine deficiency could account, at least partially, for the DNA damage observed following sperm sex sorting. To test this, we compared protamine status between unsexed and sexed spermatozoa from two bulls using the fluorochrome chromomycin A3 (CMA3) and flow cytometry. Then, we assessed embryo development following in vitro fertilization (IVF) using the same sperm treatments. Overall, sperm protamination was not different between sexed and unsexed semen. However, one of the two bulls displayed higher rates of protamine deficiency for both unsexed and sexed semen (P < 0.05). Moreover, unsexed semen from this bull yielded lower blastocyst (P < 0.05) and blastocyst hatching rates than unsexed sperm from the other bull. CMA3-positive staining was negatively correlated with cleavage (R2 85.1, P = 0.003) and blastocyst hatching (R2 87.6, P = 0.006) rates in unsexed semen. In conclusion, while the sex-sorting process had no effect on sperm protamine content, we observed a bull effect for sperm protamination, which correlated to embryo development rates following IVF.
Assuntos
Cromatina , Sêmen , Animais , Bovinos , Desenvolvimento Embrionário , Fertilização in vitro/veterinária , Masculino , Pré-Seleção do Sexo , EspermatozoidesRESUMO
In Vitro Embryo Production (IVP) is widely used to improve the reproductive efficiency of livestock animals, however increasing the embryo development rates and pregnancy outcomes is still a challenge for some species. Thus, the lack of biological knowledge hinders developing specie-specific IVP protocols. Therefore, the contributions of RNA-seq to generate relevant biological knowledge and improve the efficiency of IVP in livestock animals are reviewed herein.
RESUMO
In Vitro Embryo Production (IVP) is widely used to improve the reproductive efficiency of livestock animals, however increasing the embryo development rates and pregnancy outcomes is still a challenge for some species. Thus, the lack of biological knowledge hinders developing specie-specific IVP protocols. Therefore, the contributions of RNA-seq to generate relevant biological knowledge and improve the efficiency of IVP in livestock animals are reviewed herein.
Assuntos
Animais , Animais Domésticos/embriologia , Animais Domésticos/genética , Transferência Embrionária/veterinária , RNARESUMO
In Vitro Embryo Production (IVP) is widely used to improve the reproductive efficiency of livestock animals, however increasing the embryo development rates and pregnancy outcomes is still a challenge for some species. Thus, the lack of biological knowledge hinders developing specie-specific IVP protocols. Therefore, the contributions of RNA-seq to generate relevant biological knowledge and improve the efficiency of IVP in livestock animals are reviewed herein.(AU)
Assuntos
Animais , Animais Domésticos/embriologia , Animais Domésticos/genética , Transferência Embrionária/veterinária , RNARESUMO
A produção de búfalos está se expandindo na Amazônia, sendo assim o uso de biotecnologias reprodutivas em programas de melhoramento genético tornou-se uma estratégia para melhorar a produtividade dos rebanhos sem a necessidade de aumentar as áreas de pastagens. A Produção In Vitro de Embriões (PIVE) é uma das biotecnologias disponíveis, a qual é contiuamente aperfeiçoada através da pesquisa de novos componentes para os meios de cultivo e da pesquisa de protocolos espécie específicos que resultem em maior número de embriões de boa qualidade. Contudo, a falta de informações sobre os requerimentos metabólicos de gametas e embriões têm dificultado a consolidação de protocolos de PIVE específicos para búfalos. Neste artigo discutimos as abordagens transcriptômicas que estão ajudando a preencher esta falta de informações, as limitações destas abordagens e os tópicos de pesquisa que ainda precisam ser investigados em búfalos.
Buffalo production is expanding in the Amazon region therefore the use of reproductive biotechnologies in breeding programs became a strategy to improve the herd productivity without a need for increasing pasture areas. In Vitro Production (IVP) is one of the available biotechnologies, which is continuously being improved through the research of novel components of culture media and the research of specie-specific protocols to obtain an increased number of good quality embryos. However, the lack of information about the metabolic requirements of gametes and embryos have delayed the consolidation of buffalos IVP specific protocols. Herein, we discussed the transcriptomic approaches that are helping to fill the lack of information, the limitations of these approaches and the research topics that still needs further investigations in buffaloes.
Assuntos
Animais , Búfalos/genética , Embrião de Mamíferos , Transcriptoma/genética , Técnicas In VitroRESUMO
O rebanho bovino brasileiro no período de 1975 a 2017 passou de 101.673.753 para 171.858.168 de animais, o que representa um crescimento de 69%, sendo que 77% desse crescimento ocorreu na Amazônia, onde no mesmo período, o rebanho cresceu 1.066%. Mas, a derrubada da floresta cresceu na mesma proporção colocando a região no centro das discussões nacionais e internacionais em relação ao meio ambiente. Em 2012 foi aprovado o novo código florestal o qual determina que na Amazônia deve ser preservado 80% da área da propriedade como reserva legal (RL), restando 20% a ser explorado economicamente. Apesar da questão ambiental, é inegável que a pecuária colocou a região dentro do contexto econômico nacional. Portanto, o desafio é: é possível manter o desenvolvimento da pecuária na Amazônia de forma sustentável, dentro da concepção da nova lei? É dentro desse contexto que abordaremos de forma superficial essa grande questão, na certeza de que para respondê-la precisará de um profundo debate pela sociedade.
The Brazilian cattle herd in between 1975 and 2017 rose from 101,673,753 to 171,858,168 of animals, representing a growth of 69%, of which 77% of this growth occurred in the Amazon, where in the same period the herd grew 1.066%. However, the deforestation has grown at the same rate, putting the region at the center of national and international environmental discussions. In 2012 it was approved the new forest law that states that 80% of the property area must be kept as legal reserve (RL), whereas only 20% remaining economically exploitable. Despite the environmental issue, it is undeniable that livestock farming has placed the region within the national economic context. So the challenge is: Is it possible to sustainably maintain the livestock development in the Amazon region? It is within this context that we will superficially address this great question, in the certainty that in order to answer it, it will require a deep debate by society.
Assuntos
Animais , Criação de Animais Domésticos/legislação & jurisprudência , Criação de Animais Domésticos/tendênciasRESUMO
O rebanho bovino brasileiro no período de 1975 a 2017 passou de 101.673.753 para 171.858.168 de animais, o que representa um crescimento de 69%, sendo que 77% desse crescimento ocorreu na Amazônia, onde no mesmo período, o rebanho cresceu 1.066%. Mas, a derrubada da floresta cresceu na mesma proporção colocando a região no centro das discussões nacionais e internacionais em relação ao meio ambiente. Em 2012 foi aprovado o novo código florestal o qual determina que na Amazônia deve ser preservado 80% da área da propriedade como reserva legal (RL), restando 20% a ser explorado economicamente. Apesar da questão ambiental, é inegável que a pecuária colocou a região dentro do contexto econômico nacional. Portanto, o desafio é: é possível manter o desenvolvimento da pecuária na Amazônia de forma sustentável, dentro da concepção da nova lei? É dentro desse contexto que abordaremos de forma superficial essa grande questão, na certeza de que para respondê-la precisará de um profundo debate pela sociedade.(AU)
The Brazilian cattle herd in between 1975 and 2017 rose from 101,673,753 to 171,858,168 of animals, representing a growth of 69%, of which 77% of this growth occurred in the Amazon, where in the same period the herd grew 1.066%. However, the deforestation has grown at the same rate, putting the region at the center of national and international environmental discussions. In 2012 it was approved the new forest law that states that 80% of the property area must be kept as legal reserve (RL), whereas only 20% remaining economically exploitable. Despite the environmental issue, it is undeniable that livestock farming has placed the region within the national economic context. So the challenge is: Is it possible to sustainably maintain the livestock development in the Amazon region? It is within this context that we will superficially address this great question, in the certainty that in order to answer it, it will require a deep debate by society.(AU)
Assuntos
Animais , Criação de Animais Domésticos/legislação & jurisprudência , Criação de Animais Domésticos/tendênciasRESUMO
A produção de búfalos está se expandindo na Amazônia, sendo assim o uso de biotecnologias reprodutivas em programas de melhoramento genético tornou-se uma estratégia para melhorar a produtividade dos rebanhos sem a necessidade de aumentar as áreas de pastagens. A Produção In Vitro de Embriões (PIVE) é uma das biotecnologias disponíveis, a qual é contiuamente aperfeiçoada através da pesquisa de novos componentes para os meios de cultivo e da pesquisa de protocolos espécie específicos que resultem em maior número de embriões de boa qualidade. Contudo, a falta de informações sobre os requerimentos metabólicos de gametas e embriões têm dificultado a consolidação de protocolos de PIVE específicos para búfalos. Neste artigo discutimos as abordagens transcriptômicas que estão ajudando a preencher esta falta de informações, as limitações destas abordagens e os tópicos de pesquisa que ainda precisam ser investigados em búfalos.(AU)
Buffalo production is expanding in the Amazon region therefore the use of reproductive biotechnologies in breeding programs became a strategy to improve the herd productivity without a need for increasing pasture areas. In Vitro Production (IVP) is one of the available biotechnologies, which is continuously being improved through the research of novel components of culture media and the research of specie-specific protocols to obtain an increased number of good quality embryos. However, the lack of information about the metabolic requirements of gametes and embryos have delayed the consolidation of buffalos IVP specific protocols. Herein, we discussed the transcriptomic approaches that are helping to fill the lack of information, the limitations of these approaches and the research topics that still needs further investigations in buffaloes.(AU)
Assuntos
Animais , Búfalos/genética , Transcriptoma/genética , Embrião de Mamíferos , Técnicas In VitroRESUMO
Nitric oxide (NO) is a cell-signaling molecule that regulates a variety of molecular pathways. We investigated the role of NO during preimplantation embryonic development by blocking its production with an inhibitor or supplementing in vitro bovine embryo cultures with its natural precursor, L-arginine, over different periods. Endpoints evaluated included blastocyst rates, development kinetics, and embryo quality. Supplementation with the NO synthase inhibitor N-Nitro-L-arginine-methyl ester (L-NAME) from Days 1 to 8 of culture decreased blastocyst (P < 0.05) and hatching (P < 0.05) rates. When added from Days 1 to 8, 50 mM L-arginine decreased blastocyst rates (P < 0.001); in contrast, when added from Days 5 to 8, 1 mM L-arginine improved embryo hatching rates (P < 0.05) and quality (P < 0.05) as well as increased POU5F1 gene expression (P < 0.05) as compared to the untreated control. Moreover, NO levels in the medium during this culture period positively correlated with the increased embryo hatching rates and quality (P < 0.05). These data suggest exerts its positive effects during the transition from morula to blastocyst stage, and that supplementing the embryo culture medium with L-arginine favors preimplantation development of bovine embryos.