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1.
Rev. bras. ciênc. avic ; 25(2): eRBCA-2022-1632, 2023. tab
Artigo em Inglês | VETINDEX | ID: biblio-1418400

Resumo

This study was conducted to determine the effect of bee pollen inclusion on the performance and gut morphology of Ross 308 broiler chickens. A total of 240-day-old chicks (120 males and 120 females) were allocated to 4 treatments in a randomized complete block design (RCBD) with sex as a block. Each experimental group was replicated 3 times with 10 chicks per replicate, with an average weight of 40 ± 5g per bird. Body weight and feed intake were measured on a weekly basis to calculate the feed conversion ratio. Gut morphology was measured on days 21 and 42. Data were analysed using the General Linear Model procedures of the Statistical Analysis System.Bee pollen inclusion in starter diets had an effect (p<0.05) on body weight and live weight gain of male Ross 308 broiler chickens. The different inclusion levels of bee pollen had an effect (p<0.05) on the gut morphology of Ross 308 broiler chickens. The ileum lengths of female broiler chickens were significantly wider (p<0.05) in comparison with male chickens. This may suggest that bee pollen inclusion has a beneficial effect on broiler chickens gut morphology during the early stages of development. It can be concluded that natural substances such as bee pollen can be a possible feed additive to replace synthetic antibiotics, since such compounds are essential for the growth and development of poultry gut.(AU)


Assuntos
Animais , Pólen/química , Galinhas/anatomia & histologia , Antibacterianos/efeitos adversos , Peso Corporal , Intestinos/microbiologia
2.
Anim. Reprod. (Online) ; 20(2): e20230085, 2023. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1452316

Resumo

The establishment and maintenance of a pregnancy that goes to term is sine qua non for the long-term sustainability of dairy and beef cattle operations. The oocyte plays a critical role in providing the factors necessary for preimplantation embryonic development. Furthermore, the female, or maternal, environment where oocytes and embryos develop is crucial for the establishment and maintenance of a pregnancy to term. During folliculogenesis, the oocyte must sequentially acquire meiotic and developmental competence, which are the results of a series of molecular events preparing the highly specialized gamete to return to totipotency after fertilization. Given that folliculogenesis is a lengthy process in the cow, the occurrence of disease, metabolic imbalances, heat stress, or other adverse events can make it challenging to maintain oocyte quality. Following fertilization, the newly formed embryo must execute a tightly planned program that includes global DNA remodeling, activation of the embryonic genome, and cell fate decisions to form a blastocyst within a few days and cell divisions. The increasing use of assisted reproductive technologies creates an additional layer of complexity to ensure the highest oocyte and embryo quality given that in vitro systems do not faithfully recreate the physiological maternal environment. In this review, we discuss cellular and molecular factors and events known to be crucial for proper oocyte development and maturation, as well as adverse events that may negatively affect the oocyte; and the importance of the uterine environment, including signaling proteins in the maternal-embryonic interactions that ensure proper embryo development. We also discuss the impact of assisted reproductive technologies in oocyte and embryo quality and developmental potential, and considerations when looking into the prospects for developing systems that allow for in vitro gametogenesis as a tool for assisted reproduction in cattle.(AU)


Assuntos
Animais , Feminino , Gravidez , Bovinos/embriologia , Colo do Útero/embriologia , Células Germinativas/citologia , Técnicas de Reprodução Assistida/veterinária , Desenvolvimento Embrionário
3.
Iheringia, Sér. zool ; 112: e2022018, 2022. graf
Artigo em Inglês | VETINDEX | ID: biblio-1421635

Resumo

We provide herein the first report of a nest of Ceratina (Ceratinula) fioreseana Oliveira, 2020, a species that was recently described for the Cerrado domain. The nest was collected in a Passiflora edulis Sims (Passifloraceae) plantation in Minas Gerais State, Brazil and was built in a trap nest, a dry petiole of Cecropia pachystachya Trécul (Urticaceae). Within the nest there was a living female and a brood cell without partition containing a pupa, whose adult female emerged 28 days after pupation. Pollen analysis revealed the dominance of Emilia fosbergii Nicolson (Asteraceae) pollen grains, a weed recorded a few meters from the nest. The record of an adult female within the nest with a pupa and the absence of nest partition might suggest social behavior in this bee species.(AU)


Primeiro registro de um ninho de Ceratina (Ceratinula) fioreseana Oliveira (Hymenoptera: Apidae). É fornecido o primeiro registro de um ninho de Ceratina (Ceratinula) fioreseana Oliveira, 2020, uma espécie que foi recentemente descrita para o domínio do Cerrado. O ninho foi coletado em um cultivo de Passiflora edulis Sims (Passifloraceae) no estado de Minas Gerais, Brasil e foi construído em um ninho-armadilha, um pecíolo seco de Cecropia pachystachya Trécul (Urticaceae). Dentro do ninho havia uma fêmea e uma célula de cria sem partição contendo uma pupa, a qual a fêmea adulta emergiu 28 dias após pupação. A análise polínica revelou a dominância de grãos de pólen de Emilia fosbergii Nicolson (Asteraceae), uma espécie ruderal observada a poucos metros do ninho. O registro de uma fêmea adulta dentro do ninho juntamente com uma pupa e a ausência de partição na célula de cria podem sugerir comportamento social nesta espécie de abelha.(AU)


Assuntos
Animais , Feminino , Pólen , Asteraceae , Himenópteros/classificação , Brasil
4.
Anim. Reprod. (Online) ; 19(4): e20230007, 2022. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1420060

Resumo

At the time of its discovery and characterization in 1994, leptin was mostly considered a metabolic hormone able to regulate body weight and energy homeostasis. However, in recent years, a great deal of literature has revealed leptin's pleiotropic nature, through its involvement in numerous physiological contexts including the regulation of the female reproductive tract and ovarian function. Obesity has been largely associated with infertility, and leptin signalling is known to be dysregulated in the ovaries of obese females. Hence, the disruption of ovarian leptin signalling was shown to contribute to the pathophysiology of ovarian failure in obese females, affecting transcriptional programmes in the gamete and somatic cells. This review attempts to uncover the underlying mechanisms contributing to female infertility associated with obesity, as well as to shed light on the role of leptin in the metabolic dysregulation within the follicle, the effects on the oocyte epigenome, and the potential long-term consequence to embryo programming.(AU)


Assuntos
Animais , Feminino , Leptina/análise , Obesidade Materna/veterinária , Infertilidade Feminina/diagnóstico , Epigenômica/métodos
5.
Braz. j. biol ; 82: e266035, 2022. tab, ilus, mapas
Artigo em Inglês | VETINDEX | ID: biblio-1420684

Resumo

This study aimed to describe and characterize the stages of gonadal development of females of Xiphopenaeus kroyeri caught by artisanal fishers in Espírito Santo state, southeastern region of Brazil. All females (n= 1,831) were subjected to macroscopic and microscopic morphological analysis (n= 333) of the ovaries. From the morphology, coloration and degree of turgidity of the fresh ovary, macroscopic analysis determined five stages of gonadal development. The macroscopic analysis showed difficulties in differentiating the immature and spawning stages due to the similarity between the colors of the ovaries, which confirms the need to perform the macroscopic and histological analysis simultaneously for fisheries management studies. Microscopic observations allowed us to analyze the following six stages of cell development: oogonia, previtellogenic oocytes, primary vitellogenic oocytes, secondary vitellogenic oocytes, mature oocytes and atretic oocytes. From this, five stages of gonadal development were defined, i.e., immature, early development, advanced development, mature and spawned. The presence of peripheral bodies was not observed in this species. These results help to clarify and better understand the reproductive and population aspects of the Atlantic Seabob, which are fundamental for the establishment of management and conservation measures of this resource.


Este estudo teve como objetivo descrever e caracterizar os estágios de desenvolvimento gonadal de fêmeas de Xiphopenaeus kroyeri capturado por pescadores artesanais no Estado do Espírito Santo, região sudeste (Região sudeste = Rio de Janeiro, São Paulo, Minas Gerais e Espírito Santo) do Brasil. Todas as fêmeas (n= 1.831) foram submetidas à análise morfológica macroscópica e microscópica (n= 333) dos ovários. A partir da morfologia, coloração e grau de turgidez do ovário fresco, a análise macroscópica determinou cinco estágios de desenvolvimento gonadal. A análise macroscópica mostrou dificuldades em diferenciar os estágios imaturo e reprodutivo devido à semelhança entre as cores dos ovários, o que confirma a necessidade de realizar a análise macroscópica e histológica simultaneamente para estudos de manejo pesqueiro. As observações microscópicas permitiram analisar os seguintes seis estágios de desenvolvimento celular: oogônias, ovócitos prévitelogênicos, ovócitos em vitelogênese primária, ovócitos em vitelogênese secundária, ovócitos maduros e ovócitos atrésicos. A partir disso, foram definidos cinco estágios de desenvolvimento gonadal, ou seja, imaturo, desenvolvimento inicial, desenvolvimento avançado, maduro e desovado. A presença de corpos periféricos não foi observada nesta espécie. Estes resultados ajudam a esclarecer e compreender melhor os aspetos reprodutivos e populacionais do camarão do Atlântico, que são fundamentais para o estabelecimento de medidas de gestão e conservação deste recurso.


Assuntos
Animais , Feminino , Ovário/crescimento & desenvolvimento , Penaeidae/crescimento & desenvolvimento , Células Germinativas , Gônadas/crescimento & desenvolvimento
6.
Semina ciênc. agrar ; 43(3): 927-942, maio.-jun. 2022. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1369239

Resumo

Research focused on female gamete vitrification has increased attention to develop a reliable cryopreservation method to preserve immature equine oocytes. Despite the intensive implementation of biotechnological procedures for horse breeding, vitrification of immature equine cumulus-oocyte complexes (COCs) remain to be clearly elucidated. We aimed to determine the relative transcript level of target genes Bone morphogenetic protein 15 (BMP15); Bcl-2-associated X protein (BAX); and Caspase 3 (CASP3) in equine COCs prior to and after vitrification. Ovarian follicles were aspirated from ovaries collected from an abattoir. A total of 240 COCs were collected and distributed into vitrified COCs (VIT, n=120) and nonvitrified (Non-VIT, n=120) groups. Then, COCs were preserved and relative transcript expressions of BMP15, BAX, CASP3 were measured and normalized against GAPDH performed by qRT-PCR. In addition, 38 COCs were evaluated to assess chromatin configuration of germinal vesicl e stage prior and after vitrification by exposure to 10 µg/ml of bisbenzimide. A difference was observed in the COCs' mRNA level of abundance for the BAX gene between the VIT (2.05 ± 0.47) and (0.85 ± 0.08) Non-VIT groups. There was no difference in mRNA relative transcript level of CASP3 and BMP15 in Non-VIT (0.63 ± 0.20 and 1.55 ± 0.73, respectively) compared to VIT (0.64 ± 0.01 and 2.84 ± 2.20, respectively) equine COCs. All COCs where considered at immature stage of development even though COCs in Non-VIT group showed higher condensed chromatin configuration compared to VIT (100% vs 60.7%, respectively). We demonstrate that BMP15 and CASP3 are detected in VIT and Non-VIT immature COCs. In conclusion, BAX is expressed highly in vitrified immature equine COCs and indicates that activation of apoptosis signaling cascades in cells exposed to vitrification.(AU)


Pesquisas sobre a vitrificação de gametas femininos estão sendo realizadas para o desenvolvimento de um método confiável de criopreservação dos complexos cumulus-oócitos (CCOs) na espécie equina. Apesar da implementação intensiva de biotecnologias reprodutivas em equinos, a vitrificação dos CCOs imaturos permanece em estágio experimental em relação à competência celular. O objetivo do estudo foi determinar o nível de transcrição relativo dos genes Proteína morfogenética óssea 15 (BMP15); Proteína X associada a Bcl-2 (BAX); e Caspase 3 (CASP3) em CCOs equinos antes e após a vitrificação. Folículos ovarianos foram aspirados de ovários coletados em matadouro. O total de 240 CCOs foi coletado e distribuído em grupos vitrificados (VIT, n=120) e não vitrificados (N-VIT, n=120). Os CCOs foram preservados e as expressões transcritas relativas de BMP15, BAX, CASP3 foram determinadas pela técnica de qRT-PCR sendo normalizadas em relação ao GAPDH. Além disso, 38 CCOs foram avaliados para determinar a configuração da cromatina no estágio de vesícula germinativa antes e após a vitrificação pela exposição a 10 µg/ml de bisbenzimida. Os resultados mostraram uma diferença no nível de abundância de mRNA dos CCOs para o gene BAX entre os grupos VIT (2,05 ± 0,47) e N-VIT (0,85 ± 0,08). Não houve diferença no nível de transcrição relativa do mRNA de CASP3 e BMP15 nos CCOs do grupo N-VIT (0,63 ± 0,20 e 1,55 ± 0,73, respectivamente) em comparação com VIT (0,64 ± 0,01 e 2,84 ± 2,20, respectivamente). Todos os CCOs foram considerados em estágio imaturo de desenvolvimento, embora os CCOs no grupo N-VIT apresentaram a configuração de cromatina condensada em maior número de células avaliadas em comparação com VIT (100% vs 60,7%, respectivamente). Demonstramos que BMP15 e CASP3 são detectados em CCOs imaturos em VIT e N-VIT. Conclui-se que o BAX é altamente expresso em CCOs equinos imaturos vitrificados sendo relacionado à sinalização de apoptose em células expostas ao processo de vitrificação.(AU)


Assuntos
Animais , Feminino , Expressão Gênica , Reação em Cadeia da Polimerase/métodos , Proteína X Associada a bcl-2/classificação , Caspase 3/classificação , Proteína Morfogenética Óssea 15/classificação , Vitrificação
7.
Semina ciênc. agrar ; 42(3): 1379-1386, mai.-jun. 2021. tab
Artigo em Inglês | VETINDEX | ID: biblio-1371328

Resumo

The aim of this study was to evaluate the effects of different levels of bee pollen in the diet of growing Japanese quails on productive performance, relative weight of the gastrointestinal organs and length of small and large intestines. A total of 650 one-day-old female Japanese quails were distributed in a completely randomized design with five treatments according to the dietary levels of bee pollen (0.0, 0.4, 0.8, 1.2, and 1.6%), five replicates, and 26 birds per experimental unit. At the end of the experimental period (35 days of age), the performance and relative weight of the gastrointestinal organs and length of small and large intestines were evaluated. The dietary inclusion of bee pollen did not influence (P > 0.05) performance, relative weight of proventriculus, gizzard, pancreas, liver, and large intestine, as well as the length of small and large intestines. However, a linear reduction (P < 0.05) was observed in the relative weight of small intestine as dietary bee pollen levels increased. The inclusion of bee pollen from 0.4 to 1.6% in the diet of growing Japanese quails did neither improve productive performance nor alter the biometry of digestive organs.(AU)


O objetivo deste estudo foi avaliar os efeitos de diferentes níveis de pólen apícola nas dietas de codornas japonesas em crescimento sobre o desempenho produtivo, peso relativo dos órgãos do trato gastrointestinal e comprimento do intestino delgado e grosso. Um total de 650 codornas japonesas, fêmeas, de um dia de idade, foram distribuídas em um delineamento inteiramente casualizado com cinco tratamentos de acordo com os níveis dietéticos do pólen apícola (0,0; 0,4; 0,8; 1,2 e 1,6%), cinco repetições e 26 aves por unidade experimental. Ao final do período experimental (35 dias de idade), o desempenho e o peso relativo dos órgãos do trato gastrointestinal e o comprimento do intestino delgado e grosso foram avaliados. A inclusão dietética de pólen de abelha não influenciou (P > 0,05) o desempenho, peso relativo do proventrículo, moela, pâncreas, fígado e intestino grosso, bem como o comprimento do intestino delgado e intestino grosso. Entretanto, uma redução linear (P < 0,05) foi observada no peso relativo do intestino delgado de acordo com o aumento dos níveis de pólen apícola. A inclusão dietética de 0,4 a 1,6% de pólen apícola para codornas japonesas em crescimento não melhorou o desempenho produtivo e não alterou a biometria dos órgãos digestivos.(AU)


Assuntos
Animais , Pólen , Biometria , Coturnix/microbiologia , Trato Gastrointestinal , Anti-Infecciosos/imunologia
8.
Anim. Reprod. (Online) ; 17(3): [e20200041], 2020. graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1461515

Resumo

Endocrine-disrupting compounds (EDCs) and foodborne contaminants are environmental pollutants that are considered reproductive toxicants due to their deleterious effects on female and male gametes. Among the EDCs, the phthalate plasticizers are of growing concern. In-vivo and in-vitro models indicate that the oocyte is highly sensitive to phthalates. This review summarizes the effects of di(2-ethylhexyl) phthalate and its major metabolite mono(2-ethyhexyl) phthalate (MEHP) on the oocyte. MEHP reduces the proportion of oocytes that fertilize, cleave and develop to the blastocyst stage. This is associated with negative effects on meiotic progression, and disruption of cortical granules, endoplasmic reticulum and mitochondrial reorganization. MEHP alters mitochondrial membrane polarity, increases reactive oxygen species levels and induces alterations in genes associated with oxidative phosphorylation. A carryover effect from the oocyte to the blastocyst is manifested by alterations in the transcriptomic profile of blastocysts developed from MEHP-treated oocytes. Among foodborne contaminants, the pesticide atrazine (ATZ) and the mycotoxin aflatoxin B1 (AFB1) are of high concern. The potential hazards associated with exposure of spermatozoa to these contaminants and their carryover effect to the blastocyst are described. AFB1 and ATZ reduce spermatozoa's viability, as reflected by a high proportion of cells with damaged plasma membrane; induce acrosome reaction, expressed as damage to the acrosomal membrane; and interfere with mitochondrial function, characterized by hyperpolarization of the membrane. ATZ and AFB1-treated spermatozoa show a high proportion of cells with fragmented DNA. Exposure of spermatozoa to AFB1 and ATZ reduces fertilization and cleavage rates, but not that of blastocyst formation. However, fertilization with AFB1- or ATZ-treated spermatozoa impairs transcript expression in the formed blastocysts, implying a carryover effect. Taken together, the review indicates the risk of exposing farm animals to environmental contaminants, and their deleterious effects on female and male gametes and the developing embryo.


Assuntos
Masculino , Feminino , Animais , Bovinos , Bovinos/anatomia & histologia , Bovinos/embriologia , Células Germinativas/citologia , Células Germinativas/crescimento & desenvolvimento , Desenvolvimento Embrionário , Espermatozoides , Oócitos
9.
Anim. Reprod. ; 17(3): [e20200041], 2020. graf, ilus
Artigo em Inglês | VETINDEX | ID: vti-28528

Resumo

Endocrine-disrupting compounds (EDCs) and foodborne contaminants are environmental pollutants that are considered reproductive toxicants due to their deleterious effects on female and male gametes. Among the EDCs, the phthalate plasticizers are of growing concern. In-vivo and in-vitro models indicate that the oocyte is highly sensitive to phthalates. This review summarizes the effects of di(2-ethylhexyl) phthalate and its major metabolite mono(2-ethyhexyl) phthalate (MEHP) on the oocyte. MEHP reduces the proportion of oocytes that fertilize, cleave and develop to the blastocyst stage. This is associated with negative effects on meiotic progression, and disruption of cortical granules, endoplasmic reticulum and mitochondrial reorganization. MEHP alters mitochondrial membrane polarity, increases reactive oxygen species levels and induces alterations in genes associated with oxidative phosphorylation. A carryover effect from the oocyte to the blastocyst is manifested by alterations in the transcriptomic profile of blastocysts developed from MEHP-treated oocytes. Among foodborne contaminants, the pesticide atrazine (ATZ) and the mycotoxin aflatoxin B1 (AFB1) are of high concern. The potential hazards associated with exposure of spermatozoa to these contaminants and their carryover effect to the blastocyst are described. AFB1 and ATZ reduce spermatozoa's viability, as reflected by a high proportion of cells with damaged plasma membrane; induce acrosome reaction, expressed as damage to the acrosomal membrane; and interfere with mitochondrial function, characterized by hyperpolarization of the membrane. ATZ and AFB1-treated spermatozoa show a high proportion of cells with fragmented DNA. Exposure of spermatozoa to AFB1 and ATZ reduces fertilization and cleavage rates, but not that of blastocyst formation. However, fertilization with AFB1- or ATZ-treated spermatozoa impairs transcript expression in the formed blastocysts, implying a carryover effect. Taken together, the review indicates the risk of exposing farm animals to environmental contaminants, and their deleterious effects on female and male gametes and the developing embryo.(AU)


Assuntos
Animais , Masculino , Feminino , Bovinos , Bovinos/embriologia , Bovinos/anatomia & histologia , Células Germinativas/citologia , Células Germinativas/crescimento & desenvolvimento , Desenvolvimento Embrionário , Espermatozoides , Oócitos
10.
Pap. avulsos zool ; 59: e.20195936, 25 mar. 2019. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1487210

Resumo

Here we provide descriptions of gynandromorphs of two species oil-collecting bees: Lophopedia nigrispinis and Epicharis iheringii, both with partial bilateral phenotypic asymmetry. The bees have a female phenotype predominantly on mesosoma and metasoma. The specimen of L. nigrispinis has distinct characteristics on legs, suggesting a mosaic pattern of gynandromorphism. The pollen and oil loads on legs suggest that the bee was foraging normally. The gynander specimen of E. iheringii has mostly a female phenotype, except for head, with right half female type and left half male type. The specimen of L. nigrispinis was collected foraging on flowers of Bidens sp. at Parque Nacional Iguazú, Argentina with loads of pollen on legs suggesting it was reproductive and was provisioning a nest. The specimen of Epicharis iheriingi has no evidence of any oil or pollen collection, despite its mostly female phenotype.


Assuntos
Animais , Abelhas/anatomia & histologia , Caracteres Sexuais , Polinização/genética , Transtornos do Desenvolvimento Sexual , Pólen
11.
Pap. avulsos Zool. ; 59: e.20195936, Oct. 3, 2019. ilus
Artigo em Inglês | VETINDEX | ID: vti-24643

Resumo

Here we provide descriptions of gynandromorphs of two species oil-collecting bees: Lophopedia nigrispinis and Epicharis iheringii, both with partial bilateral phenotypic asymmetry. The bees have a female phenotype predominantly on mesosoma and metasoma. The specimen of L. nigrispinis has distinct characteristics on legs, suggesting a mosaic pattern of gynandromorphism. The pollen and oil loads on legs suggest that the bee was foraging normally. The gynander specimen of E. iheringii has mostly a female phenotype, except for head, with right half female type and left half male type. The specimen of L. nigrispinis was collected foraging on flowers of Bidens sp. at Parque Nacional Iguazú, Argentina with loads of pollen on legs suggesting it was reproductive and was provisioning a nest. The specimen of Epicharis iheriingi has no evidence of any oil or pollen collection, despite its mostly female phenotype.(AU)


Assuntos
Animais , Abelhas/anatomia & histologia , Caracteres Sexuais , Transtornos do Desenvolvimento Sexual , Polinização/genética , Pólen
12.
Anim. Reprod. (Online) ; 16(3): 485-496, 2019. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1461458

Resumo

Follicles are composed of different interdependent cell types including oocytes, cumulus, granulosa, and theca cells. Follicular cells and oocytes exchange signaling molecules from the beginning of the development of the primordial follicles until the moment of ovulation. The follicular structure transforms during folliculogenesis; barriers form between the germ and the somatic follicular cells, and between the somatic follicular cells. As such, communication systems need to adapt to maintain the exchange of signaling molecules. Two critical barriers are established at different stages of development: the zona pellucida, separating the oocyte and the cumulus cells limiting the communication through specific connections, and the antrum, separating subpopulations of follicular cells. In both situations, communication is maintained either by the development of specialized connections as transzonal projections or by paracrine signaling and trafficking of extracellular vesicles through the follicular fluid. The bidirectional communication between the oocytes and the follicle cells is vital for driving folliculogenesis and oogenesis. These communication systems are associated with essential functions related to follicular development, oocyte competence, and embryonic quality. Here, we discuss the formation of the zona pellucida and antrum during folliculogenesis, and their importance in follicle and oocyte development. Moreover, this review discusses the current knowledge on the cellular mechanisms such as the movement of molecules via transzonal projections, and the exchange of extracellular vesicles by follicular cells to overcome these barriers to support female gamete development. Finally, we highlight the undiscovered aspects related to intrafollicular communication among the germ and somatic cells, and between the somatic follicular cells and give our perspective on manipulating the above-mentioned cellular communication to improve reproductive technologies.


Assuntos
Folículo Ovariano/crescimento & desenvolvimento , Vesículas Extracelulares/genética , Oócitos
13.
Anim. Reprod. ; 16(3): 485-496, 2019. ilus
Artigo em Inglês | VETINDEX | ID: vti-22350

Resumo

Follicles are composed of different interdependent cell types including oocytes, cumulus, granulosa, and theca cells. Follicular cells and oocytes exchange signaling molecules from the beginning of the development of the primordial follicles until the moment of ovulation. The follicular structure transforms during folliculogenesis; barriers form between the germ and the somatic follicular cells, and between the somatic follicular cells. As such, communication systems need to adapt to maintain the exchange of signaling molecules. Two critical barriers are established at different stages of development: the zona pellucida, separating the oocyte and the cumulus cells limiting the communication through specific connections, and the antrum, separating subpopulations of follicular cells. In both situations, communication is maintained either by the development of specialized connections as transzonal projections or by paracrine signaling and trafficking of extracellular vesicles through the follicular fluid. The bidirectional communication between the oocytes and the follicle cells is vital for driving folliculogenesis and oogenesis. These communication systems are associated with essential functions related to follicular development, oocyte competence, and embryonic quality. Here, we discuss the formation of the zona pellucida and antrum during folliculogenesis, and their importance in follicle and oocyte development. Moreover, this review discusses the current knowledge on the cellular mechanisms such as the movement of molecules via transzonal projections, and the exchange of extracellular vesicles by follicular cells to overcome these barriers to support female gamete development. Finally, we highlight the undiscovered aspects related to intrafollicular communication among the germ and somatic cells, and between the somatic follicular cells and give our perspective on manipulating the above-mentioned cellular communication to improve reproductive technologies.(AU)


Assuntos
Folículo Ovariano/crescimento & desenvolvimento , Vesículas Extracelulares/genética , Oócitos
14.
Braz. J. Biol. ; 78(2): 255-264, maio-ago. 2018. graf, tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-735335

Resumo

Mytella guyanensis, consumed and commercialized in coastal regions of Brazil, is one of several bivalve species of socioeconomic interest for coastal communities. Besides serving as a source of income and subsistence for these communities, it also contributes to their food security as it is a source of proteins and micronutrients. Thus, the reproductive cycle of this species was studied aiming to contribute to food security and its preservation. Samples were collected monthly, between March 2014 and March 2015, in a natural stock (12°38'50"S; 38°51'43"W) in a Marine Reserve (RESEX Bay of Iguape) (community Engenho da Ponte), Bahia, Brazil. Mytella guyanensis is collected by women on site, where the artisanal fishing of this resource is performed without following any specific handling procedure. Also, empirical evidence indicates overexploitation. The specimens collected were measured along the anterior-posterior axis (length), and after macroscopic analysis they were fixed in Davidson solution, processed by routine histology techniques and stained with Harris haematoxylin and eosin (H&E). The macroscopic analysis showed sexual dimorphism, with the male and female gonads presenting a milky-white and orange colour, respectively. A 1:1 sex ratio (M: F) was observed and reproduction of the species was continuous all year round. March, April, July and August were the months with highest values of gamete elimination. We suggest that a M. guyanensis management plan should restrict capture during these months, in order to sustainably regulate exploitation of this food resource in this reserve.(AU)


Mytella guyanensis, consumida e comercializada em regiões litorâneas do Brasil, é uma das diversas espécies de bivalves de interesse socioeconômico para comunidades litorâneas. Além de servir como fonte de renda e subsistência para essas comunidades, esta contribui para a sua segurança alimentar, por ser fonte de proteínas e micronutrientes. Assim, o ciclo reprodutivo desta espécie foi estudado visando contribuir com a segurança alimentar e a preservação da mesma. As amostragens foram realizadas mensalmente, entre março de 2014 e março de 2015 em um estoque natural (12°38'50"S e 38°51'43"W) na Reserva Extrativista Marinha Baía do Iguape (comunidade Engenho da Ponte), Bahia. Mytella guyanensis é coletada no local por mulheres, onde a pesca artesanal desse recurso é realizada sem seguir nenhum procedimento específico de manejo e evidência empírica indica sobrexplotação. Os espécimes coletados foram medidos ao longo do eixo ântero-posterior (comprimento) e após a análise macroscópica, foram fixados em solução de Davidson, processados por técnicas rotineiras de histologia e coradas em hematoxilina de Harris e eosina (HE). A análise macroscópica evidenciou dimorfismo sexual, com as gônadas de machos e fêmeas apresentando coloração branco leitosa e alaranjada, respectivamente. Uma proporção sexual (M: F) de 1:1 foi observada e a reprodução foi contínua ao longo do ano. Março, abril, julho e agosto apresentaram os maiores valores de eliminação de gametas. Sugerimos que um plano de manejo de M. guyanensis restrinja a captura deste durante esses meses, a fim de regular de forma sustentável a exploração desse recurso nesta reserva.(AU)


Assuntos
Animais , Mytilidae/crescimento & desenvolvimento , Fenômenos Reprodutivos Fisiológicos , Estágios do Ciclo de Vida , Segurança Alimentar , Conservação dos Recursos Naturais , Brasil
15.
Artigo em Inglês | VETINDEX | ID: vti-694497

Resumo

Abstract Mytella guyanensis, consumed and commercialized in coastal regions of Brazil, is one of several bivalve species of socioeconomic interest for coastal communities. Besides serving as a source of income and subsistence for these communities, it also contributes to their food security as it is a source of proteins and micronutrients. Thus, the reproductive cycle of this species was studied aiming to contribute to food security and its preservation. Samples were collected monthly, between March 2014 and March 2015, in a natural stock (12°38'50S; 38°51'43W) in a Marine Reserve (RESEX Bay of Iguape) (community Engenho da Ponte), Bahia, Brazil. Mytella guyanensis is collected by women on site, where the artisanal fishing of this resource is performed without following any specific handling procedure. Also, empirical evidence indicates overexploitation. The specimens collected were measured along the anterior-posterior axis (length), and after macroscopic analysis they were fixed in Davidson solution, processed by routine histology techniques and stained with Harris haematoxylin and eosin (H&E). The macroscopic analysis showed sexual dimorphism, with the male and female gonads presenting a milky-white and orange colour, respectively. A 1:1 sex ratio (M: F) was observed and reproduction of the species was continuous all year round. March, April, July and August were the months with highest values of gamete elimination. We suggest that a M. guyanensis management plan should restrict capture during these months, in order to sustainably regulate exploitation of this food resource in this reserve.


Resumo Mytella guyanensis, consumida e comercializada em regiões litorâneas do Brasil, é uma das diversas espécies de bivalves de interesse socioeconômico para comunidades litorâneas. Além de servir como fonte de renda e subsistência para essas comunidades, esta contribui para a sua segurança alimentar, por ser fonte de proteínas e micronutrientes. Assim, o ciclo reprodutivo desta espécie foi estudado visando contribuir com a segurança alimentar e a preservação da mesma. As amostragens foram realizadas mensalmente, entre março de 2014 e março de 2015 em um estoque natural (12°38'50S e 38°51'43W) na Reserva Extrativista Marinha Baía do Iguape (comunidade Engenho da Ponte), Bahia. Mytella guyanensis é coletada no local por mulheres, onde a pesca artesanal desse recurso é realizada sem seguir nenhum procedimento específico de manejo e evidência empírica indica sobrexplotação. Os espécimes coletados foram medidos ao longo do eixo ântero-posterior (comprimento) e após a análise macroscópica, foram fixados em solução de Davidson, processados por técnicas rotineiras de histologia e coradas em hematoxilina de Harris e eosina (HE). A análise macroscópica evidenciou dimorfismo sexual, com as gônadas de machos e fêmeas apresentando coloração branco leitosa e alaranjada, respectivamente. Uma proporção sexual (M: F) de 1:1 foi observada e a reprodução foi contínua ao longo do ano. Março, abril, julho e agosto apresentaram os maiores valores de eliminação de gametas. Sugerimos que um plano de manejo de M. guyanensis restrinja a captura deste durante esses meses, a fim de regular de forma sustentável a exploração desse recurso nesta reserva.

16.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467065

Resumo

Abstract Mytella guyanensis, consumed and commercialized in coastal regions of Brazil, is one of several bivalve species of socioeconomic interest for coastal communities. Besides serving as a source of income and subsistence for these communities, it also contributes to their food security as it is a source of proteins and micronutrients. Thus, the reproductive cycle of this species was studied aiming to contribute to food security and its preservation. Samples were collected monthly, between March 2014 and March 2015, in a natural stock (12°38'50S; 38°51'43W) in a Marine Reserve (RESEX Bay of Iguape) (community Engenho da Ponte), Bahia, Brazil. Mytella guyanensis is collected by women on site, where the artisanal fishing of this resource is performed without following any specific handling procedure. Also, empirical evidence indicates overexploitation. The specimens collected were measured along the anterior-posterior axis (length), and after macroscopic analysis they were fixed in Davidson solution, processed by routine histology techniques and stained with Harris haematoxylin and eosin (H&E). The macroscopic analysis showed sexual dimorphism, with the male and female gonads presenting a milky-white and orange colour, respectively. A 1:1 sex ratio (M: F) was observed and reproduction of the species was continuous all year round. March, April, July and August were the months with highest values of gamete elimination. We suggest that a M. guyanensis management plan should restrict capture during these months, in order to sustainably regulate exploitation of this food resource in this reserve.


Resumo Mytella guyanensis, consumida e comercializada em regiões litorâneas do Brasil, é uma das diversas espécies de bivalves de interesse socioeconômico para comunidades litorâneas. Além de servir como fonte de renda e subsistência para essas comunidades, esta contribui para a sua segurança alimentar, por ser fonte de proteínas e micronutrientes. Assim, o ciclo reprodutivo desta espécie foi estudado visando contribuir com a segurança alimentar e a preservação da mesma. As amostragens foram realizadas mensalmente, entre março de 2014 e março de 2015 em um estoque natural (12°38'50S e 38°51'43W) na Reserva Extrativista Marinha Baía do Iguape (comunidade Engenho da Ponte), Bahia. Mytella guyanensis é coletada no local por mulheres, onde a pesca artesanal desse recurso é realizada sem seguir nenhum procedimento específico de manejo e evidência empírica indica sobrexplotação. Os espécimes coletados foram medidos ao longo do eixo ântero-posterior (comprimento) e após a análise macroscópica, foram fixados em solução de Davidson, processados por técnicas rotineiras de histologia e coradas em hematoxilina de Harris e eosina (HE). A análise macroscópica evidenciou dimorfismo sexual, com as gônadas de machos e fêmeas apresentando coloração branco leitosa e alaranjada, respectivamente. Uma proporção sexual (M: F) de 1:1 foi observada e a reprodução foi contínua ao longo do ano. Março, abril, julho e agosto apresentaram os maiores valores de eliminação de gametas. Sugerimos que um plano de manejo de M. guyanensis restrinja a captura deste durante esses meses, a fim de regular de forma sustentável a exploração desse recurso nesta reserva.

17.
Tese em Português | VETTESES | ID: vtt-222240

Resumo

A alta pressão gasosa (HGP, do inglês high gaseous pressure) tem sido descrita como um agente estressante capaz de induzir respostas ao estresse subletal, fornecendo proteção celular e estímulos positivos a desafios subsequentes, como a criopreservação, produção in vitro de embriões (PIVE) , entre outras biotécnicas da reprodução, embora os mecanismos celulares, a modulação epigenética e as modificações no padrão de expressão gênica envolvidos ainda não estejam totalmente elucidados. Este princípio foi investigado em gametas bovinos e embriões murinos no presente trabalho. Foram realizados dois experimentos independentes. No primeiro, avaliou-se o efeito da exposição de oócitos bovinos no estádio de vesículas germinativa à HGP na eficiência e cinética de desenvolvimento da PIVE por fecundação in vitro (FIV). Os resultados revelaram que oócitos expostos a HGP em temperatura ambiente apresentaram taxa de maturação in vitro (MIV) e cinética de desenvolvimento até o estádio de blastocisto semelhantes ao controle mantido em condições ideais durante o tratamento do grupo experimental, diferentemente do observado no grupo com CCOs mantidos em temperatura ambiente durante a exposição à HGP. Em um segundo experimento, observou-se as alterações no padrão de expressão gênica de blastocistos murinos expostos previamente à alta pressão gasosa no estádio de embrião de 8-células, bem como se este desafio alterava a taxa de sobrevivência destes blastocistos após serem submetidos ao processo de criopreservação. A análise do padrão de transcrição revelou que um gene associado ao estresse oxidativo (Sod2) teve sua expressão aumentada, enquanto genes de proliferação e desenvolvimento (Igf2 e Igf2R) tiveram sua expressão reduzida, quando comparados com os embriões no estádio de 8-células, embora a relação Igf2/Igf2R não demonstrou ser afetada. O tratamento por HGP mostrou-se eficiente no aumento da taxa de sobrevivência de blastocistos após a criopreservação. Os experimentos permitiram concluir que a resposta ao estresse subletal estimulada pela HGP é eficiente na melhora da performance de gametas femininos e embriões submetidos a novas situações estressantes.


High gaseous pressure (HGP) has been described as stressor, providing cell protection and positive stimuli to subsequent challenges like cryopreservation, embryo in vitro production (IVP), among other reproduction biotechnologies, although cells mechanisms, epigenetic modulation and transcriptional modifications are not totally elucidated. This principle was investigated in bovine gametes and murine embryos in this report at two independent studies. First, the effect of bovine oocyte exposure to HGP in germinal vesicle stage was evaluated to efficiency and development kinect of IVP by in vitro fertilization (IVF). Results showed that oocytes exposed to HGP at room temperature had in vitro maturation (IVM) rate and developmental kinect to reach the blastocyst stage similar to control group kept in ideal conditions during experimental group treatment, differently that what was observed in the group with COCs just kept at room temperature during HGP exposure. In the second experiment, modifications in transcriptional response were observed in murine blastocysts previously exposed to HGP when embryo 8-cells stage, as well if this challenge modified survival rate of this blastocysts after cryopreservation procedures. The analysis of the transcriptional pattern revealed that a gene associated to oxidative stress (Sod2) was upregulated, while genes of proliferation and development (Igf2 and Igf2R) were downregulated, when compared with 8- cells embryos, even though the ratio Igf2/Igf2R appeared not be affected. HGP treatment showed to be efficient to improve blastocyst survival rate to cryopreservation. The experiments enable inferring that subletal response stimulated by HGP was efficient to enhance performance of female gametes and embryos exposed to new stressor situations.

18.
Anim. Reprod. (Online) ; 12(1): 93-104, Jan.-Mar.2015. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1461148

Resumo

Genetically-modified domestic animal models are of increasing significance in biomedical research and agriculture. As authentic ES cells derived from domestic animals are not yet available, the prevailing approaches for engineering genetic modifications in those animals are pronuclear microinjection and somatic cell nuclear transfer (SCNT, also known as cloning). Both pronuclear microinjection and SCNT are inefficient, costly, and time-consuming. In animals produced by pronuclear microinjection, the exogenous transgene is usually inserted randomly into the genome, which results in highly variable expression patterns and levels in different founders. Therefore, significant efforts are required to generate and screen multiple founders to obtain animals with optimal transgene expression. For SCNT, specific genetic modifications (both gain-of-function and loss-of-function) can be engineered and carefully selected in the somatic cell nucleus before nuclear transfer. SCNT has been used to generate a variety of genetically modified animals such as goats, pigs, sheep and cattle; however, animals resulting from SCNT frequently suffer from developmental abnormalities associated with incomplete nuclear reprogramming. Other strategies to generate genetically-modified animals rely on the use of the spermatozoon as a natural vector to introduce genetic material into the female gamete. This sperm mediated DNA transfer (SMGT) combined with intracytoplasmatic sperm injection (ICSI) has relatively high efficiency and allows the insertion of large DNA fragments, which, in turn, enhance proper gene expression. An approach currently being developed to complement SCNT for producing genetically modified animals is germ cell transplantation using genetically modified male germline stem cells (GSCs). This approach relies on the ability of GSCs that are genetically modified in vitro to colonize the recipient testis and produce donor derived sperm upon transplantation.


Assuntos
Animais , Animais Domésticos/genética , Técnicas de Reprogramação Celular/métodos , Nucleases dos Efetores Semelhantes a Ativadores de Transcrição
19.
Anim. Reprod. ; 12(1): 93-104, Jan.-Mar.2015. ilus
Artigo em Inglês | VETINDEX | ID: vti-745430

Resumo

Genetically-modified domestic animal models are of increasing significance in biomedical research and agriculture. As authentic ES cells derived from domestic animals are not yet available, the prevailing approaches for engineering genetic modifications in those animals are pronuclear microinjection and somatic cell nuclear transfer (SCNT, also known as cloning). Both pronuclear microinjection and SCNT are inefficient, costly, and time-consuming. In animals produced by pronuclear microinjection, the exogenous transgene is usually inserted randomly into the genome, which results in highly variable expression patterns and levels in different founders. Therefore, significant efforts are required to generate and screen multiple founders to obtain animals with optimal transgene expression. For SCNT, specific genetic modifications (both gain-of-function and loss-of-function) can be engineered and carefully selected in the somatic cell nucleus before nuclear transfer. SCNT has been used to generate a variety of genetically modified animals such as goats, pigs, sheep and cattle; however, animals resulting from SCNT frequently suffer from developmental abnormalities associated with incomplete nuclear reprogramming. Other strategies to generate genetically-modified animals rely on the use of the spermatozoon as a natural vector to introduce genetic material into the female gamete. This sperm mediated DNA transfer (SMGT) combined with intracytoplasmatic sperm injection (ICSI) has relatively high efficiency and allows the insertion of large DNA fragments, which, in turn, enhance proper gene expression. An approach currently being developed to complement SCNT for producing genetically modified animals is germ cell transplantation using genetically modified male germline stem cells (GSCs). This approach relies on the ability of GSCs that are genetically modified in vitro to colonize the recipient testis and produce donor derived sperm upon transplantation.(AU)


Assuntos
Animais , Animais Domésticos/genética , Técnicas de Reprogramação Celular/métodos , Nucleases dos Efetores Semelhantes a Ativadores de Transcrição
20.
Tese em Português | VETTESES | ID: vtt-219480

Resumo

A criopreservação de gametas é uma das ferramentas mais promissoras para a preservação de material genético, útil tanto na conservação de espécies ameaçadas de extinção quanto de interesse econômico e agropecuário. Embora a criopreservação de sêmen de peixes já esteja consolidada, são restritos os relativos sucessos na criopreservação de gametas femininos de peixes. Muitos são os problemas acarretados pela não perda de material genético materno tais como, redução na variabilidade genética, perda do material genético mitocondrial e RNAs mensageiros indispensáveis para o desenvolvimento inicial do embrião. Há muitas décadas, pesquisadores tentam encontrar o equilíbrio necessário entre as substâncias utilizadas como crioprotetores e a técnica adequada de resfriamento e aquecimento. No entanto, mesmo com as diversas variações experimentadas, os problemas ainda parecem ser os mesmos: injúrias celulares causadas pela variação de temperatura, estresse osmótico e o alto grau de citotoxicidade dos crioprotetores, além de problemas reportados mais recentemente como a mutagênese, fragmentação de DNA e cromossomos. Alguns criobiologistas e cientistas de áreas afins pesquisam novas alternativas e diferentes conceitos e etapas da criopreservação que vão desde a intensificação das curvas de resfriamento e aquecimento, quanto a busca por novas soluções crioprotetoras que de fato protejam as células. Nesse contexto, o objetivo desse estudo foi avaliar a capacidade crioprotetora do Alginato de Sódio. Trata-se de um polissacarídeo natural extraído de algas marrons, e foi escolhido com agente crioprotetor não permeável por possuir a capacidade de absorver e reter líquidos além de ser uma substância atóxica. Pela primeira vez utilizado na criopreservação de tecido ovariano de peixes, utilizamos o zebrafish como modelo animal. Além disso, avaliamos o potencial comportamento crioprotetor do Alginato de Sódio tanto isoladamente como crioprotetor, quanto em combinações com outros agentes crioprotetores convencionas como o Tese de Doutorado em Zootecnia Produção animal, Faculdade de Agronomia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brasil. (89p.) Dezembro, 2020. C2H6OS (DMSO), propilenoglicol, metanol e sacarose. E os resultados obtidos com a utilização do Alginato de Sódio foram surpreendentes, dado que houve resultados positivos para a criopreservação de folículos em estágios I e II, além de ocorrências, mesmo que isoladas, de oócitos em elevado grau de maturação, sem alterações morfológicas. Embora haja a necessidade de estudos massivos acerca dessa biomolécula na criobiologia, o conteúdo deste estudo sugere que o uso do Alginato de Sódio pode ser uma escolha saudável de agente crioprotetor não permeável, além de torná-lo objeto de pesquisa na área.


Gamete cryopreservation is one of the most promising tools for preserving genetic material, useful both for the conservation of endangered species and for economic and agricultural interest. Although the cryopreservation of fish semen is already consolidated, relative successes in the cryopreservation of female fish gametes are restricted. There are many problems caused by the non-loss of maternal genetic material such as, reduction in genetic variability, loss of mitochondrial genetic material and mRNAs indispensable for the initial development of the embryo. For many decades, researchers have tried to find the necessary balance between the substances used as cryoprotectants and the appropriate cooling and heating technique. However, even with several variations experienced, the problems still seem to be the same, cell injuries caused by temperature variation, osmotic stress and the high level of cryoprotectants cytotoxicity, in addition to other problems that new studies discover with each new result, such as example mutagen, fragmentation of DNA and chromosomes. Some cryobiologists and scientists from related fields are researching new alternatives and different concepts and stages of cryopreservation process, ranging from intensifying the cooling and heating curves, to the search for new cryoprotective solutions that actually protect cells. In this context, the aim of this study was to evaluate the cryoprotective capacity of sodium alginate. Because it is one natural polysaccharide extracted from brown algae, and was chosen as a non-permeable cryoprotective agent because it has the ability to absorb and retain liquids in addition to being a non-toxic substance. For the first time used in the cryopreservation in fish ovarian tissue, we used zebrafish as an animal model. In addition, we evaluated the potential cryoprotective behavior of sodium alginate both alone and with cryoprotectant, and in combinations with other conventional cryoprotectants such as C2H6OS (DMSO), propylene glycol, methanol and sucrose. And the results obtained with the use of sodium alginate were surprising, given that there were positive results for the cryopreservation of follicles in stages I and II, in Doctoral thesis in Animal Science, Faculdade de Agronomia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. (89 p.) Dezember, 2020. addition to occurrences even if isolated from oocytes in a high degree of maturation, without morphological changes. Although there is a need for massive studies about this biomolecule in cryobiology, the content of this study suggests that the use of sodium alginate may be a healthy choice of non-permeable cryoprotective agent, in addition to making it an object of research in this area.

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