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1.
Anim Reprod ; 20(1): e20230017, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37101424

RESUMO

The puma population is constantly decreasing, and cloning by somatic cell nuclear transfer can be used to conserve the species. One of the factors determining the success of the development of cloned embryos is the cell cycle stage of the donor cells. We evaluated the effects of full confluency (~100%), serum starvation (0.5% serum), and roscovitine (15 µM) treatments on the cell cycle synchronization in G0/G1 of puma skin-derived fibroblasts by flow cytometric analysis. Also, we assessed the effects of these synchronization methods on morphology, viability, and apoptosis levels using microscopy tools. The results showed that culturing the cells to confluence for 24 h (84.0%), 48 h (84.6%), and 72 h (84.2%) and serum starvation for 96 h (85.4%) yielded a significantly higher percentage of cells arrested in the G0/G1 (P 0.05) phase than cells not subjected to any cell cycle synchronization method (73.9%). Nevertheless, while serum starvation reduced the percentage of viable cells, no difference was observed for the full confluence and roscovitine treatments (P 0.05). Moreover, roscovitine for 12 h (78.6%) and 24 h (82.1%) was unable to synchronize cells in G0/G1 (P 0.05). In summary, full confluency induces puma fibroblast cell cycle synchronization at the G0/G1 stage without affecting cell viability. These outcomes may be valuable for planning donor cells for somatic cell nuclear transfer in pumas.

2.
Anim. Reprod. (Online) ; 20(1): e20230017, 2023. graf, ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1427272

RESUMO

The puma population is constantly decreasing, and cloning by somatic cell nuclear transfer can be used to conserve the species. One of the factors determining the success of the development of cloned embryos is the cell cycle stage of the donor cells. We evaluated the effects of full confluency (~100%), serum starvation (0.5% serum), and roscovitine (15 µM) treatments on the cell cycle synchronization in G0/G1 of puma skin-derived fibroblasts by flow cytometric analysis. Also, we assessed the effects of these synchronization methods on morphology, viability, and apoptosis levels using microscopy tools. The results showed that culturing the cells to confluence for 24 h (84.0%), 48 h (84.6%), and 72 h (84.2%) and serum starvation for 96 h (85.4%) yielded a significantly higher percentage of cells arrested in the G0/G1 (P < 0.05) phase than cells not subjected to any cell cycle synchronization method (73.9%). Nevertheless, while serum starvation reduced the percentage of viable cells, no difference was observed for the full confluence and roscovitine treatments (P > 0.05). Moreover, roscovitine for 12 h (78.6%) and 24 h (82.1%) was unable to synchronize cells in G0/G1 (P > 0.05). In summary, full confluency induces puma fibroblast cell cycle synchronization at the G0/G1 stage without affecting cell viability. These outcomes may be valuable for planning donor cells for somatic cell nuclear transfer in pumas.(AU)


Assuntos
Animais , Feminino , Panthera/genética , Fibroblastos/fisiologia , Pele , Sincronização do Estro/genética , Técnicas de Transferência Nuclear/veterinária , Roscovitina/efeitos adversos
3.
Rev. bras. reprod. anim ; 47(2): 286-293, abr.-jun. 2023.
Artigo em Português | VETINDEX | ID: biblio-1435393

RESUMO

A criação de cães de raça vem aumentando significativamente, consequentemente a exigência de serviços veterinários no mercado para lidar com essa categoria específica também aumentou. Em especial, temos os serviços de reprodução que crescem devido a procura por melhoria da qualidade de plantel, uma vez que pela incrementação de biotécnicas é possível dinamizar o potencial de crescimento da criação. Logo, é ideal que o profissional que irá prestar este serviço seja altamente capacitado para sua realização, tendo noções não somente de reprodução, mas também de outras necessidades que a criação de cães requer. É importante que o profissional saiba selecionar os animais adequados a reprodução, tanto reprodutores, quanto matrizes, além de quando realizar os procedimentos, assim, evitar protocolos desnecessários e que possam comprometer a criação. Desta forma, o profissional pode fornecer o serviço mais completo possível, fazendo com que esse profissional seja referência no mercado.(AU)


The breeding of purebred dogs has increased significantly, consequently the demand for veterinary services on the market to deal with this specific category has also increased. In particular, we have reproduction services that grow due to the demand for improving the quality of the herd, since by increasing biotechniques it is possible to boost the growth potential of creation. Therefore, it is ideal that the professional who will provide this service is highly qualified for its performance, having notions not only of reproduction, but also of other needs that dog breeding requires. It is important that the professional knows how to select the appropriate animals for reproduction, both breeders and matrices, in addition to when to perform the procedures, thus avoiding unnecessary protocols that could compromise the creation. In this way, the professional can provide the most complete service possible, making this professional a reference on the market.(AU)


Assuntos
Animais , Cães , Médicos Veterinários , Neonatologia/métodos , Obstetrícia/métodos
4.
Rev. bras. reprod. anim ; 47(2): 294-299, abr.-jun. 2023. tab
Artigo em Português | VETINDEX | ID: biblio-1435412

RESUMO

Poucas informações a respeito da biologia dos procionídeos estão disponíveis para quem busca conhecer mais sobre essas espécies. Entretanto, alguns estudos a respeito da reprodução destes animais foram realizados. As principais espécies encontradas no Brasil são o quati, o guaxinim e o jupará, e, dentre esses, o quati se destaca por ser o que possui o maior número de informações reprodutivas. A maioria dos procionídeos aparece como espécies não ameaçadas, porém a falta de informações sobre estes animais pode fazer com que estes dados possam estar defasados. É importante o conhecimento reprodutivo dos procionídeos pois, devido as ações antrópicas que ocasionam a perda de habitat natural, essas espécies, em breve, podem entrar para a lista de animais ameaçados de extinção. Assim, esse artigo tem como objetivo descrever alguns dados por meios de estudos reprodutivos que podem auxiliar ao desenvolvimento de estratégias de conservação dessas espécies.(AU)


Little information about the biology of procyonids is available for those who want to know more about these species. However, some studies regarding the reproduction of these animals were developed. The main species found in Brazil are coati, raccoon, and kinkajou, among which the coati stands out for being the one with the highest number of reproductive information. Most procyonids appear as non-threatened species, but the lack of information about these animals may cause these data to be outdated. Reproductive knowledge of procyonids is important because, due to anthropic actions that cause loss of natural habitat, these species may soon enter on the list of endangered animals. Thus, this article aims to describe some data by means of reproductive studies that can help to develop conservation strategies for these species.(AU)


Assuntos
Animais , Comportamento Sexual Animal , Procyonidae/fisiologia , Brasil
5.
Anim Reprod ; 19(3): e20210069, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36156885

RESUMO

Morphological sperm evaluation supported by the morphometry can be used in the determination of the seminal quality and in the investigation of potential extenders. Although there are studies comparing TRIS and ACP extenders, there are no comparative studies between them for the computerized assisted semen analysis (CASA), sperm viability, membrane functionality and sperm morphometry parameters of cryopreserved canine semen. Hence, we aimed to evaluate the effects of ACP-106c and TRIS on post-freezing canine sperm quality. Five dogs were submitted to semen collection twice with one-week interval. The semen was evaluated within the parameters: total motility, vigor, concentration, viability, plasma membrane functionality, morphology and morphometry. In the morphometric evaluation, the morphologically normal sperm was measured as: length, width, area and perimeter of the head and the midpiece, tail length and total length. The parameters of ellipticity, elongation, regularity and roughness were determined. Then, the semen was divided into two aliquots that were diluted in TRIS or ACP-106c, with the addition of egg yolk and glycerol. The diluted semen was refrigerated and frozen. The thawed samples were evaluated. Total motility, viability, sperm membrane functionality and normal morphology reduced after thawing in both extenders (morphology reduced from 89.60 ± 1.3% to 84.40 ± 1.8 and 84.60 ± 1.1% in TRIS and ACP-106c, respectively). However, it did not differ between TRIS and ACP-106c. In the ACP-106c the sperm head defects in cryopreserved semen were higher compared to fresh semen (P < 0.05). For all the morphometric parameters evaluated, there were no differences between fresh and cryopreserved samples (3.70 ± 0.4% vs. 2.30 ± 0.5%). In kinetics, with an interval of one week statistical differences between the extenders were found only in the parameters ALH and LIN (P < 0.05). Regardless of the extender, there were no changes in the morphometric parameters of sperm after thawing.

6.
Anim Reprod ; 19(1): e20210093, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35371300

RESUMO

Heterologous in vitro fertilization (IVF) is an important tool for assessing fertility of endangered mammals such as the jaguar, considering difficult access to females for artificial insemination and to obtain homologous oocytes. We aimed to evaluate the fertility of jaguar sperm cryopreserved with different extenders, using domestic cat oocytes to assess the development of hybrid embryos. Semen from four captive jaguars was obtained by electroejaculation. Samples were cryopreserved in powdered coconut water (ACP-117c) or Tris extender containing 20% egg yolk and 6% glycerol. Thawed spermatozoa were resuspended (2.0 × 106 spermatozoa/mL) in IVF medium and co-incubated with cat oocytes matured in vitro for 18 h. Presumptive zygotes were cultured for 7 days. After 48 h, cleavage rate was evaluated, and non-cleaved structures were stained for IVF evaluation. On days 5 and 7, the rate of morula and blastocyst formation was assessed. Data were analyzed using the Fisher exact test (p < 0.05). No difference was observed between ACP-117c and Tris extenders, respectively, for oocytes with 2nd polar body (2/51, 3.9 ± 2.9% vs. 2/56, 3.6 ± 3.1%), pronuclear structures (5/51, 9.8 ± 4.7% vs. 8/56, 14.3 ± 8.0%), and total IVF rates (7/36, 19.4 ± 5.0% vs. 10/37, 27.0 ± 13.8%). All the samples fertilized the oocytes, with 22.9 ± 3.2% (16/70) and 16.7 ± 3.6% (12/72) cleavage of mature oocytes for ACP-117c and Tris extenders, respectively. Morula rates of 4.3 ± 2.3% (3/70) and 5.6 ± 2.2% (4/72) were observed for ACP-117c and Tris, respectively. Only the Tris extender demonstrated blastocyst production (2/12, 16.7 ± 1.5% blastocyst/cleavage). We demonstrated that jaguar ejaculates cryopreserved using ACP-117c and Tris were suitable for IVF techniques, with blastocyst production by ejaculates cryopreserved in Tris. This is a first report of embryos produced in vitro using jaguar sperm and domestic cat oocytes through IVF.

7.
Anim. Reprod. (Online) ; 19(3): e20210069, set. 2022. tab
Artigo em Inglês | VETINDEX | ID: biblio-1393202

RESUMO

Morphological sperm evaluation supported by the morphometry can be used in the determination of the seminal quality and in the investigation of potential extenders. Although there are studies comparing TRIS and ACP extenders, there are no comparative studies between them for the computerized assisted semen analysis (CASA), sperm viability, membrane functionality and sperm morphometry parameters of cryopreserved canine semen. Hence, we aimed to evaluate the effects of ACP-106c and TRIS on post-freezing canine sperm quality. Five dogs were submitted to semen collection twice with one-week interval. The semen was evaluated within the parameters: total motility, vigor, concentration, viability, plasma membrane functionality, morphology and morphometry. In the morphometric evaluation, the morphologically normal sperm was measured as: length, width, area and perimeter of the head and the midpiece, tail length and total length. The parameters of ellipticity, elongation, regularity and roughness were determined. Then, the semen was divided into two aliquots that were diluted in TRIS or ACP-106c, with the addition of egg yolk and glycerol. The diluted semen was refrigerated and frozen. The thawed samples were evaluated. Total motility, viability, sperm membrane functionality and normal morphology reduced after thawing in both extenders (morphology reduced from 89.60 ± 1.3% to 84.40 ± 1.8 and 84.60 ± 1.1% in TRIS and ACP-106c, respectively). However, it did not differ between TRIS and ACP-106c. In the ACP106c the sperm head defects in cryopreserved semen were higher compared to fresh semen (P < 0.05). For all the morphometric parameters evaluated, there were no differences between fresh and cryopreserved samples (3.70 ± 0.4% vs. 2.30 ± 0.5%). In kinetics, with an interval of one week statistical differences between the extenders were found only in the parameters ALH and LIN (P < 0.05). Regardless of the extender, there were no changes in the morphometric parameters of sperm after thawing.(AU)


Assuntos
Animais , Masculino , Cães , Processamento de Imagem Assistida por Computador , Criopreservação/veterinária , Análise do Sêmen/veterinária , Sobrevivência Celular
8.
Anim. Reprod. (Online) ; 19(1): e20210093, 2022. tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1363335

RESUMO

Heterologous in vitro fertilization (IVF) is an important tool for assessing fertility of endangered mammals such as the jaguar, considering difficult access to females for artificial insemination and to obtain homologous oocytes. We aimed to evaluate the fertility of jaguar sperm cryopreserved with different extenders, using domestic cat oocytes to assess the development of hybrid embryos. Semen from four captive jaguars was obtained by electroejaculation. Samples were cryopreserved in powdered coconut water (ACP-117c) or Tris extender containing 20% egg yolk and 6% glycerol. Thawed spermatozoa were resuspended (2.0 × 106 spermatozoa/mL) in IVF medium and co-incubated with cat oocytes matured in vitro for 18 h. Presumptive zygotes were cultured for 7 days. After 48 h, cleavage rate was evaluated, and non-cleaved structures were stained for IVF evaluation. On days 5 and 7, the rate of morula and blastocyst formation was assessed. Data were analyzed using the Fisher exact test (p < 0.05). No difference was observed between ACP-117c and Tris extenders, respectively, for oocytes with 2nd polar body (2/51, 3.9 ± 2.9% vs. 2/56, 3.6 ± 3.1%), pronuclear structures (5/51, 9.8 ± 4.7% vs. 8/56, 14.3 ± 8.0%), and total IVF rates (7/36, 19.4 ± 5.0% vs. 10/37, 27.0 ± 13.8%). All the samples fertilized the oocytes, with 22.9 ± 3.2% (16/70) and 16.7 ± 3.6% (12/72) cleavage of mature oocytes for ACP-117c and Tris extenders, respectively. Morula rates of 4.3 ± 2.3% (3/70) and 5.6 ± 2.2% (4/72) were observed for ACP-117c and Tris, respectively. Only the Tris extender demonstrated blastocyst production (2/12, 16.7 ± 1.5% blastocyst/cleavage). We demonstrated that jaguar ejaculates cryopreserved using ACP-117c and Tris were suitable for IVF techniques, with blastocyst production by ejaculates cryopreserved in Tris. This is a first report of embryos produced in vitro using jaguar sperm and domestic cat oocytes through IVF.(AU)


Assuntos
Animais , Masculino , Sêmen , Blastocisto , Inseminação Artificial , Fertilização in vitro , Panthera , Técnicas In Vitro
9.
Reprod Domest Anim ; 56(10): 1342-1348, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34333798

RESUMO

Testicular vitrification is an alternative to preserve the genetic material of pre-pubertal animals. However, there are few studies on post-vitrification warming. Hence, the aim was to compare the influence of different warming temperatures on vitrified testicular fragments from pre-pubertal cats. The testicles were fragmented and divided into a control group (non-vitrified) and vitrified, using an association between dimethylsulphoxide and glycerol. The vitrified fragments were warmed at 50, 55 and 60°C/5 s. Morphological and morphometric evaluations were carried out using classical histology. Afterwards, the mitochondrial activity was evaluated using Rhodamine 123. The data were expressed in mean and standard error. The differences were considered significant when p < .05. In the histomorphological analysis, the testicular fragment presented seminiferous tubules with poorly developed germinal epithelium, compatible with pre-pubertal animals. The group warmed at 50°C presented similar to the control regarding the maintenance of the integrity of the tubules and cells, without stromal rupture and lamina propria alteration, as well as regarding the maintenance of the junctions between the cells. The group warmed at 55°C showed reduction of the cell junctions, and the one warmed at 60°C had increased detachment of the basement membrane (p < .05). The warming caused a reduction in the tubular diameter inversely proportional and progressive to the increase in temperature, with the highest diameter in the control group and the lowest in the 60°C group. The control group showed a lower incidence of Rhodamine 123, followed in ascending order of the warmings at 55 and 60°C. The higher mitochondrial activity was obtained with 50°C, showing an increase of the metabolic cell function at this temperature. It was concluded that the testicular fragment of pre-pubertal cats presents a better preserved morphology, morphometry and viability when warmed at 50°C.


Assuntos
Gatos , Criopreservação/veterinária , Temperatura , Testículo , Vitrificação , Animais , Sobrevivência Celular , Criopreservação/métodos , Masculino , Mitocôndrias/metabolismo , Túbulos Seminíferos
10.
Cryobiology ; 101: 52-60, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34118241

RESUMO

Somatic resource banks play a crucial role in the conservation of genetic diversity, allowing for the preservation of biological samples from different populations. Puma somatic cells can be recovered from these banks and used in assisted techniques toward enhancing their multiplication and conservation. In response to the population reduction of this ecologically importance species, we aimed to evaluate the capacity of cryopreservation of somatic tissues on the maintenance of the integrity and quality of the cells recovered after culture, with the aim of establishing a somatic tissue bank that will allow for the safeguarding of a wide genetic sampling of pumas. Cryopreservation increased the thickness of the corneum layer in the tissues, and the number of perinuclear halos and empty gaps. Nevertheless, cryopreservation was able to maintain normal fibroblast patterns, even showing an increase in the percentage of collagen fibers. Cryopreservation maintained the proliferative potential of the tissues and the parameters evaluated during in vitro culture, mainly regarding the viability, proliferative activity, and apoptosis levels. Nevertheless, cells from cryopreserved tissues showed decreased metabolism and mitochondrial membrane potential when compared to cells from non-cryopreserved tissues. In summary, we demonstrated for the first time that puma somatic tissues subjected to cryopreservation are viable and maintain tissue integrity, featuring minimal changes after warming. Although viable somatic cells are obtained from these tissues, they undergo alterations in their metabolism and mitochondrial membrane potential. Improvements in the conservation conditions of somatic samples are needed to increase the quality of somatic tissue banks in this species.


Assuntos
Criopreservação , Puma , Animais , Criopreservação/métodos , Fibroblastos , Bancos de Tecidos , Vitrificação
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