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1.
Ciênc. rural (Online) ; 53(11): e20220508, 2023. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1439877

Resumo

ABSTRACT: Spermatozoa experience oxidative, osmotic, chemical, and thermal stresses when cooled, which degrade the quality and fertilizing capacity of the cells. Adding antioxidants to the sperm extender mitigates these alterations. This study evaluated the effect of isoespintanol (ISO) on boar semen subjected to cooling. Fifteen ejaculates from five boars (Susscrofadomestica) were extended in Beltsville thawing solution (BTS) supplemented with 0 µM (control), 5 µM (ISO5), 10 µM (ISO10), 15 µM (ISO15), 20 µM (ISO20), 25 µM (ISO25), and 30 µM (ISO30) of ISO, which were then cooled for five days at 16 °C. Sperm kinetics, total motility (TM), and progressive motility (PM) were evaluated every 24 h using an IVOS computer-assisted sperm analysis (CASA) system. On day 1 and day 5 of cooling, a hypoosmotic test, spectrofluorometry, and flow cytometry were performed to evaluate the following: membrane functionality, measured as a function of hypoosmotic swelling (HOS); total antioxidant capacity (TAC); reactive oxygen species (ROS); and mitochondrial membrane potential (Δ¥M). Regression analysis and comparison of means using the Duncan test were performed. The ISO added had a slight impact on sperm motility, as evidenced by a reduction in TM at 24 h of cooling (but not prior) with the addition of 20 µM of ISO. Similarly, no effect of the ISO on the kinetics and functional integrity of the sperm membrane was observed at 96 h of cooling; however, the regression coefficients indicated that the ISO lowered the rate of decrease in sperm motility and the proportion of rapid spermatozoa relative to the concentration of ISO used. The ISO did not affect the TAC of the cooled semen; however, different concentrations of ISO lowered ROS production in the semen after 96 h of cooling. ISO also impacted the Δ¥M of the spermatozoa at 0 h of cooling, increasing the proportion of low Δ¥M cells and decreasing the proportion of high Δ¥M cells. In conclusion, ISO can reduce the loss of quality and oxidative stress occurring in boar semen during cooling and can modulate the mitochondrial activity of sperm.


RESUMO: Durante a refrigeração, os espermatozoides sofrem estresse oxidativo, osmótico, químico e térmico, que diminuem sua qualidade e afetam sua capacidade de fertilização. A adição de antioxidantes ao diluente espermático é uma alternativa para mitigar essas alterações. O objetivo desta pesquisa foi avaliar o efeito do isospintanol (ISO) na refrigeração do sêmen suíno. Quinze ejaculados de cinco varrascos (Sus scrofa domestica) foram diluídos em BTS suplementado com ISO a 0 (controle), 5 (ISO5), 10 (ISO10), 15 (ISO15), 20 (ISO20), 25 (ISO25) e 30 (ISO30) µM e foram refrigerados por cinco dias a 16 °C. A motilidade total (MT), motilidade progressiva (MP) e cinética dos espermatozóides foram avaliadas a cada 24 h com um sistema CASA IVOS. Nos dias um e cinco de refrigeração, foram avaliadas a funcionalidade da membrana, a capacidade antioxidante total (CAT), as espécies reativas de oxigênio (ROS) e o potencial de membrana mitocondrial (Δ¥M), através do teste hiposmótico (HOS), espectrofluorimetría e citometria de fluxo. Foram realizadas análises de regressão e comparação de médias, pelo teste de Duncan. A adição de ISO teve pouca influência na motilidade espermática, apresentando apenas redução na MT em 24 h de refrigeração, devido à adição de 20 µM. Da mesma forma, não foi observada influência de ISO na cinética e integridade funcional da membrana em 96 horas de refrigeração; porém, os coeficientes de regressão mostraram que ISO produziu menor taxa de diminuição da motilidade e proporção de espermatozoides rápidos dependendo da concentração utilizada. ISO não influenciou significativamente na CAT do sêmen refrigerado; entretanto, diferentes concentrações de ISO reduziram a produção de EROs a partir do sêmen após de 96 h de refrigeração. ISO também influenciou o Δ¥M dos espermatozóides em 0 h de refrigeração, com aumento das células de baixo Δ¥M e diminuição das células de alto Δ¥M. Em conclusão, o isospintanol pode reduzir a perda da qualidade e o estresse oxidativo do sêmen suíno durante a refrigeração e pode modular a atividade mitocondrial do esperma.

2.
Arq. bras. med. vet. zootec. (Online) ; 73(5): 1047-1057, Sept.-Oct. 2021. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345276

Resumo

Colostrum is the main source of immunoglobulins (Ig) for neonate piglets and plays a crucial role within the health and growth of the piglet. Currently in pig farming, there are still no widespread practical methods for measuring the Ig concentration in colostrum at herd level. We evaluated sows' colostrum IgG concentration using an optical and a digital Brix refractometer and their performance was correlated to an IgG ELISA test, and flow cytometry. Colostrum concentrations of IgG and IgA averaged 74.05 ± 21.37mg/mL and 20.2 ± 5.32mg/mL respectively. The mean value of the Brix percentages for optical refractometer was 26.32%, and for digital was 28.32%. The Brix refractometer measurements of colostrum samples presented high correlation for IgG content analyzed by ELISA (Optical = 0.74, Digital = 0.87; P <0.001). Considering the immunophenotyping, the values for IgG and IgA lymphoblasts indicated a highly significant relationship to ELISA (IgG=0.77, IgA=0.84; P<0.001). The Brix refractometer can be considered a useful tool to be included in a colostrum monitoring program to improve potentially neonatal health. In addition, we demonstrated that flow cytometry can be an important tool to analyze and characterize the immunological potential of sow colostrum.(AU)


O colostro é a principal fonte de imunoglobulinas (Ig) para leitões recém-nascidos e desempenha um papel crucial na saúde e no crescimento dos leitões. Atualmente, na suinocultura, ainda não existem métodos amplamente utilizados na prática de produção para medir a concentração de imunoglobulinas no colostro suíno. Avaliou-se a concentração de IgG no colostro de porcas usando refratômetros Brix óptico e digital, e o desempenho foi comparado com ELISA e citometria de fluxo. As concentrações de IgG e IgA no colostro foram 74,05 ± 21,37mg/mL e 20,2 ± 5,32mg/mL, respectivamente. A percentagem de Brix média das amostras de colostro para o refratômetro óptico foi 26,32%, e para o digital foi 28,32%. As medições dos refratômetros de Brix apresentaram elevada correlação com a concentrações de IgG medidas por ELISA (óptico=0,74, digital=0,87; P<0,001). Considerando a imunofenotipagem, os valores dos linfoblastos IgG e IgA apresentaram alta correlação com o ELISA (IgG=0,77, IgA=0,84; P<0,001). O refratômetro Brix pode ser considerado uma ferramenta útil para ser incluída em um programa de monitoramento de colostro para melhorar a saúde neonatal. Além disso, foi demonstrado que a citometria de fluxo pode ser uma ferramenta importante para analisar e caracterizar o potencial imunológico do colostro de porcas.(AU)


Assuntos
Animais , Feminino , Gravidez , Imunoglobulina G , Colostro , Sus scrofa/imunologia , Imunoglobulina A , Citometria de Fluxo/veterinária
3.
Anim. Reprod. ; 18(4): e20200257, 2021. graf, ilus
Artigo em Inglês | VETINDEX | ID: vti-765787

Resumo

The access to sufficient numbers of spermatogonial stem cells (SSCs) is a prerequisite for the study of their regulation and further biomanipulation. Rho kinase (ROCK) belongs to a family of serine/threonine kinases and involves in a wide range of fundamental cellular functions. The aim of the present study was to study the effect of ROCK inhibitor, Y-27632 (0.1-40 µM), during the primary culture of ovine SSCs. SSCs were collected from 3-5-month-olds lamb testes. The viability of SSCs, the apoptosis assay of SSCs, the intracellular reactive oxygen species (ROS) analysis, and the SSCs markers and apoptosis-related gene expressions were detected by MTT reduction assay, Annexin V–FITC/ Propidium Iodide (PI) dual staining, flow cytometry and real-time-PCR studies, respectively. Morphological analyses indicated that the 5-10 µM Y-27632 had an optimal effect on the number of presumptive SSCs colonies and the area covered by them after a 10 days culture. The cell viability, apoptosis and necrosis of SSCs after 10 days culture were not affected in comparison with the control group, and the 20 µM of Y-27632 resulted in significantly decreased cell viability (P<0.05) and an increased necrosis of cells. On day 10 after culture, the expression of P53 was decreased with an increase from 0 to 10 µM in the Y-27632 dose. In the 20 µM Y-27632 group, the expressions of P53 and Bax were higher and the Bcl-2 was lower than other groups and these values were significantly different from 5 and 10 µM Y-27632 groups (P<0.05). The level of intracellular ROS was decreased with an increase in the Y-27632 dose from 5 to 20 µM in comparison with the control group. In conclusion, the present study demonstrated that Y-27632 at a concentration of 5-10 µM provided optimal culture conditions for the primary culture of ovine SSCs.(AU)


Assuntos
Animais , Masculino , Ovinos , Células-Tronco , Inibidores de Proteínas Quinases/análise , Espermatogônias , Citometria de Fluxo
4.
Anim. Reprod. (Online) ; 18(4): e20200257, 2021. graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1355651

Resumo

Abstract The access to sufficient numbers of spermatogonial stem cells (SSCs) is a prerequisite for the study of their regulation and further biomanipulation. Rho kinase (ROCK) belongs to a family of serine/threonine kinases and involves in a wide range of fundamental cellular functions. The aim of the present study was to study the effect of ROCK inhibitor, Y-27632 (0.1-40 µM), during the primary culture of ovine SSCs. SSCs were collected from 3-5-month-old's lamb testes. The viability of SSCs, the apoptosis assay of SSCs, the intracellular reactive oxygen species (ROS) analysis, and the SSCs markers and apoptosis-related gene expressions were detected by MTT reduction assay, Annexin V-FITC/ Propidium Iodide (PI) dual staining, flow cytometry and real-time-PCR studies, respectively. Morphological analyses indicated that the 5-10 µM Y-27632 had an optimal effect on the number of presumptive SSCs colonies and the area covered by them after a 10 days culture. The cell viability, apoptosis and necrosis of SSCs after 10 days' culture were not affected in comparison with the control group, and the 20 µM of Y-27632 resulted in significantly decreased cell viability (P<0.05) and an increased necrosis of cells. On day 10 after culture, the expression of P53 was decreased with an increase from 0 to 10 µM in the Y-27632 dose. In the 20 µM Y-27632 group, the expressions of P53 and Bax were higher and the Bcl-2 was lower than other groups and these values were significantly different from 5 and 10 µM Y-27632 groups (P<0.05). The level of intracellular ROS was decreased with an increase in the Y-27632 dose from 5 to 20 µM in comparison with the control group. In conclusion, the present study demonstrated that Y-27632 at a concentration of 5-10 µM provided optimal culture conditions for the primary culture of ovine SSCs.

5.
Acta sci. vet. (Impr.) ; 49: Pub. 1820, 2021. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1363850

Resumo

Sperm sexing aims to separate sperm populations in carriers of the "X" or "Y" chromosome. Currently, flow cytometry is a technique that allows greater accuracy; however, it causes structural changes in sperm, reduces viability, and has a high cost. As a result, other methods have been researched, including immunosexing, which uses monoclonal antibodies to detect sex-specific surface antigens. Thus, the objective of this study was to evaluate the immunosexing technique using a monoclonal antibody against sex-specific protein (HY) in the conservation of ram and goat semen in ACP101/102c. Ejaculates from five rams and five goats were collected with the aid of an artificial vagina; they were evaluated and submitted to the immunosexing protocol, according to the manufacturer's recommendations, using the Monoclonal Antibody Kit specific for mammalian sperm with "Y" chromosomes (HY; HY Biotechnology, Rio de Janeiro, RJ, Brazil). After sexing, the supernatant was resuspended in the cryopreservation diluent: ACP ram (ACP101/102c + 20% egg yolk + 7% glycerol) and ACP goat (ACP101/102c + 2.5% egg yolk + 7% glycerol), packaged in 0.25 mL straws, refrigerated at 4°C, stabilized for 30 min, frozen in liquid nitrogen vapor (-60°C) for 15 min, immersed in liquid nitrogen, and stored in cryogenic cylinders. The samples were evaluated in natura (T1), after immunosexing (T2) and after thawing (T3) for sperm motility subjectively using conventional microscopy (40x). Plasma membrane integrity (IMP) and sperm cell morphology were evaluated by the smear staining technique using eosin-nigrosine dye, and the percentages of healthy and morphologically defect spermatozoa were determined. In the evaluation of ram semen regarding sperm motility and IMP, no statistically significant differences were observed between treatments after sexing in the evaluation of absolute data (P > 0.05), with the difference being observed only between T1 and T2, and T3 (P < 0.05). Regarding the relative percentage and sperm morphology, no statistically significant differences were observed (P > 0.05). Regarding the evaluation of goat semen samples, the motility parameters were consistent with the technique submitted; however, the IMP data did not appear as expected, requiring further evaluation for a better assessment of the technique for this species. The data obtained from ram semen submitted to the immunosexing protocol, regarding the absolute evaluation of motility and IMP, demonstrated that the non-sexed semen (T1) was superior to the sexed treatments (T2 and T3); however, it is noteworthy that freezing started with approximately 50% of the cells, since the immunosexing technique results in a loss of viability of approximately 50% of the sperm, which corresponds to the ratio of sperm carrying the X chromosome. In addition, when the data in this study were transformed into relative values, no statistical differences were observed, indicating that the immunosexing protocol, as well as the freezing protocol, did not significantly affect the quality of ram sperm cells. In relation to the immunosexing of goat semen, future studies should be conducted in vitro to define a more appropriate protocol for the species and, in addition, in vivo studies should be performed to prove the quality of the technique. It was concluded that the immunosexing process using a monoclonal antibody against sex-specific protein (HY) associated with the use of powdered coconut water diluent (ACP101/102c) in the cryopreservation of semen proved to be efficient in the in vitro evaluation of ovine species.(AU)


Assuntos
Animais , Masculino , Sêmen , Análise para Determinação do Sexo/métodos , Análise para Determinação do Sexo/veterinária , Ruminantes , Ovinos , Criopreservação/tendências , Técnicas In Vitro
6.
Anim. Reprod. (Online) ; 17(2): e20190130, 2020. tab
Artigo em Inglês | VETINDEX | ID: biblio-1461498

Resumo

Boar spermatozoa are very susceptible to cryopreservation injuries and, for this reason, pig remains one of the few species in which fresh semen is still preferred to thawed one for routine artificial insemination (AI). The present work evaluated the effect of supplementing boar sperm thawing medium with Silvafeed SP (SSP), a mixture of Chestnut and Quebracho wood extracts (60/40 w/w) rich in polyphenols (92.4% tannin content) on in vitro fertilization (IVF) and on the following sperm parameters: sperm motility (assessed by CASA), viability, acrosome integrity, mitochondrial function and lipid peroxidation (assessed by flow cytometry) and capacitation status (immunolocalization of tyrosine phosphorylated proteins). Thawed spermatozoa were incubated 1 h at 37°C in BTS without (CTR) or with (5, 10, 20 µg/mL) SSP. After incubation sperm suspension was divided in three aliquots: one was used for IVF trials, one for sperm analysis, and the last one was capacitated for 1 h at 39°C 5% CO2 in IVF medium. Sperm motility parameters, viability, acrosome integrity, mitochondrial functionality, lipid peroxidation and tyrosine phosphorylated protein immunolocalization, used as capacitation parameter, were not influenced by SSP. However, oocytes inseminated with thawed spermatozoa pretreated with all the different SSP concentrations presented a significant (P < 0.01) increase in penetration rate compared to CTR. In addition, 5 µg/mL SSP exerted a positive effect (P<0.05) on the total efficiency of fertilization. These results encourage the use of SSP in the thawing medium since post-thawing fertility is a limit for the large-scale use of boar frozen semen.


Assuntos
Masculino , Animais , Fertilização in vitro/métodos , Preservação do Sêmen/veterinária , Sus scrofa/fisiologia , Extratos Vegetais
7.
Anim. Reprod. ; 17(2): e20190130, 2020. tab
Artigo em Inglês | VETINDEX | ID: vti-28119

Resumo

Boar spermatozoa are very susceptible to cryopreservation injuries and, for this reason, pig remains one of the few species in which fresh semen is still preferred to thawed one for routine artificial insemination (AI). The present work evaluated the effect of supplementing boar sperm thawing medium with Silvafeed SP (SSP), a mixture of Chestnut and Quebracho wood extracts (60/40 w/w) rich in polyphenols (92.4% tannin content) on in vitro fertilization (IVF) and on the following sperm parameters: sperm motility (assessed by CASA), viability, acrosome integrity, mitochondrial function and lipid peroxidation (assessed by flow cytometry) and capacitation status (immunolocalization of tyrosine phosphorylated proteins). Thawed spermatozoa were incubated 1 h at 37°C in BTS without (CTR) or with (5, 10, 20 µg/mL) SSP. After incubation sperm suspension was divided in three aliquots: one was used for IVF trials, one for sperm analysis, and the last one was capacitated for 1 h at 39°C 5% CO2 in IVF medium. Sperm motility parameters, viability, acrosome integrity, mitochondrial functionality, lipid peroxidation and tyrosine phosphorylated protein immunolocalization, used as capacitation parameter, were not influenced by SSP. However, oocytes inseminated with thawed spermatozoa pretreated with all the different SSP concentrations presented a significant (P < 0.01) increase in penetration rate compared to CTR. In addition, 5 µg/mL SSP exerted a positive effect (P<0.05) on the total efficiency of fertilization. These results encourage the use of SSP in the thawing medium since post-thawing fertility is a limit for the large-scale use of boar frozen semen.(AU)


Assuntos
Animais , Masculino , Sus scrofa/fisiologia , Fertilização in vitro/métodos , Preservação do Sêmen/veterinária , Extratos Vegetais
8.
Acta sci. vet. (Impr.) ; 48: Pub.1740-Jan. 30, 2020. ilus, tab
Artigo em Português | VETINDEX | ID: biblio-1458263

Resumo

Background: Sperm sexing is increasing in use because pre-determining the sex of the calf allows greater profitability and promotes significant gains in the productive systems that utilize the technique. Deployment of a low-cost and practical preservation methodol-ogy may further favor the cost-benefit ratio. Flow cytometry, the most commonly used sexing technique, has high costs and is very restricted. As an alternative, immunosexing has been studied, which uses sex-specific monoclonal antibodies. Thus, the objective of this study was to evaluate the immunosexing technique in conjunction with cryopreservation in ACP-102c and examine its economic aspects with regard to ram semen.Materials, Methods & Results: Ejaculates from two ram individuals were collected with the aid of an artificial vagina, evaluated, and submitted to the immunosexing protocol, according to the manufacturer’s recommendations, using the Monoclonal Antibody Kit specific for mammalian sperm with “Y” chromosomes (HY; HY Biotechnology, Rio de Janeiro-RJ, Brazil). After sexing, the supernatant was resuspended in the cryopreservation diluent: ACP (ACP-102c + 20% egg yolk + 7% glycerol), packaged in 0.25 mL straws, refrigerated to 4°C, stabilized for 30 min, frozen in liquid nitrogen vapors (-60°C) for 15 min, immersed in liquid nitrogen, and stored in cryogenic cylinders. The samples were thawed and evaluated for sperm kinetics both by using computerized semen analysis with SCA® software (Sperm Class Analyzer version 5.0) and subjectively comparing specimens from the two animals using conventional microscopy (40x). Plasma membrane integrity (IMP) and sperm cell morphology were evaluated by the smear staining technique...


Assuntos
Animais , Alimentos de Coco , Criopreservação/veterinária , Espermatozoides , Ovinos , Preservação do Sêmen/economia , Preservação do Sêmen/veterinária , Cocos , Custos e Análise de Custo
9.
Arq. bras. med. vet. zootec. (Online) ; 71(3): 752-760, May-June 2019. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1011321

Resumo

O objetivo do presente estudo foi avaliar o efeito da adição de plasma seminal de garanhões de alta e baixa fertilidade sobre a congelabilidade e a viabilidade de espermatozoides do ejaculado (EJ) e do epidídimo (EP) de garanhões subférteis. Foram utilizados seis garanhões com histórico de subfertilidade. Após coleta, espermatozoides do ejaculado foram divididos em três alíquotas: BotuSêmen® (EJ-CT); plasma seminal de alta qualidade espermática (EJ-PS1); e plasma seminal de baixa qualidade espermática (EJ-PS2). O mesmo protocolo foi realizado com espermatozoides da cauda do epidídimo após orquiectomia (EP-CT; EP-PS1; EP-PS2). Foram realizadas avaliações da cinética espermática pelo CASA e análises de integridade de membrana, acrossoma, fragmentação de DNA, capacitação espermática e peroxidação espermática por citometria de fluxo. Não foram observadas diferenças na cinética espermática entre EJ e EP, logo após a descongelação. Porém, foi observada maior (P<0,05) porcentagem de células com membranas plasmática e acrossomal íntegras nos grupos EP (EP-CT:31,7±7,5b; EP-PS1:35,2±7,0b; EP-PS2:33,9±7,2b) em comparação aos grupos EJ (EJ-CT:15,1±4,9a; EJ-PS1:11,7±4,5a; EJ-PS2:13,1±5,2a). Adicionalmente, foram observadas diferenças no índice de fragmentação de DNA (EJ-CT:2,6±0,6a; EJ-PS1:2,4±0,8a; EJ-PS2:3,0±0,8a; EP-CT:1,4±0,4b; EP-PS1:1,2±0,3b; EP-PS2:1,3±0,2b). Concluiu-se que a adição de 20% de plasma seminal, oriundo de animais férteis ou subférteis, previamente à congelação de espermatozoides epidídimários de animais subférteis não interfere na qualidade espermática.(AU)


The aim of this study was to compare the effect of the addition of seminal plasma from high and low fertility stallions on sperm viability of frozen-thawed sperm cells from ejaculate and from epididymal tail of subfertile stallions. Six stallions with a history of subfertility were used. After collection, ejaculate spermatozoa were divided into three aliquots: Botu-Semen® (EJ-CT); High-quality seminal plasma (EJ-PS1); Low-quality seminal plasma (EJ-PS2). The same was done with sperm cells from epididymis tail after orchiectomy (EP-CT; EP-PS1; EP-PS2). Evaluations of sperm kinetics were assessed by CASA and membrane and acrosome integrity, DNA fragmentation, sperm capacitation and sperm peroxidation were assessed by flow cytometry. After thawing, no differences were observed between ejaculated sperm (EJ) and epididymal sperm (EP) in any CASA evaluations. However, higher (P< 0.05) percentage of cells with intact plasma and acrossomal membranes was observed in EP groups (EP-CT:31.7±7.5b; EP-PS1:35.2±7.0b; EP-PS2:33.9±7.2b) compared to EJ groups (EJ-CT:15.1±4.9a, EJ-PS1:11.7±4.5a, EJ-PS2:13.1±5,2a). In addition, differences in DNA fragmentation index were observed (EJ-CT:2.6±0.6a; EJ-PS1:2.4±0.8a; EJ-PS2:3.0±0.8a; CT:1.4±0.4b; EP-PS1:1.2±0.3b; EP-PS2:1.3±0.2b). It was concluded that the addition of 20% seminal plasma from fertile or subfertile animals prior to the freezing of epididymal spermatozoa from subfertile animals does not interfere in sperm quality.(AU)


Assuntos
Animais , Masculino , Sêmen , Criopreservação/veterinária , Epididimo , Análise do Sêmen/veterinária , Cavalos , Infertilidade Masculina/veterinária
10.
Arq. bras. med. vet. zootec. (Online) ; 71(3): 752-760, May-June 2019. tab
Artigo em Português | VETINDEX | ID: vti-25532

Resumo

O objetivo do presente estudo foi avaliar o efeito da adição de plasma seminal de garanhões de alta e baixa fertilidade sobre a congelabilidade e a viabilidade de espermatozoides do ejaculado (EJ) e do epidídimo (EP) de garanhões subférteis. Foram utilizados seis garanhões com histórico de subfertilidade. Após coleta, espermatozoides do ejaculado foram divididos em três alíquotas: BotuSêmen® (EJ-CT); plasma seminal de alta qualidade espermática (EJ-PS1); e plasma seminal de baixa qualidade espermática (EJ-PS2). O mesmo protocolo foi realizado com espermatozoides da cauda do epidídimo após orquiectomia (EP-CT; EP-PS1; EP-PS2). Foram realizadas avaliações da cinética espermática pelo CASA e análises de integridade de membrana, acrossoma, fragmentação de DNA, capacitação espermática e peroxidação espermática por citometria de fluxo. Não foram observadas diferenças na cinética espermática entre EJ e EP, logo após a descongelação. Porém, foi observada maior (P<0,05) porcentagem de células com membranas plasmática e acrossomal íntegras nos grupos EP (EP-CT:31,7±7,5b; EP-PS1:35,2±7,0b; EP-PS2:33,9±7,2b) em comparação aos grupos EJ (EJ-CT:15,1±4,9a; EJ-PS1:11,7±4,5a; EJ-PS2:13,1±5,2a). Adicionalmente, foram observadas diferenças no índice de fragmentação de DNA (EJ-CT:2,6±0,6a; EJ-PS1:2,4±0,8a; EJ-PS2:3,0±0,8a; EP-CT:1,4±0,4b; EP-PS1:1,2±0,3b; EP-PS2:1,3±0,2b). Concluiu-se que a adição de 20% de plasma seminal, oriundo de animais férteis ou subférteis, previamente à congelação de espermatozoides epidídimários de animais subférteis não interfere na qualidade espermática.(AU)


The aim of this study was to compare the effect of the addition of seminal plasma from high and low fertility stallions on sperm viability of frozen-thawed sperm cells from ejaculate and from epididymal tail of subfertile stallions. Six stallions with a history of subfertility were used. After collection, ejaculate spermatozoa were divided into three aliquots: Botu-Semen® (EJ-CT); High-quality seminal plasma (EJ-PS1); Low-quality seminal plasma (EJ-PS2). The same was done with sperm cells from epididymis tail after orchiectomy (EP-CT; EP-PS1; EP-PS2). Evaluations of sperm kinetics were assessed by CASA and membrane and acrosome integrity, DNA fragmentation, sperm capacitation and sperm peroxidation were assessed by flow cytometry. After thawing, no differences were observed between ejaculated sperm (EJ) and epididymal sperm (EP) in any CASA evaluations. However, higher (P< 0.05) percentage of cells with intact plasma and acrossomal membranes was observed in EP groups (EP-CT:31.7±7.5b; EP-PS1:35.2±7.0b; EP-PS2:33.9±7.2b) compared to EJ groups (EJ-CT:15.1±4.9a, EJ-PS1:11.7±4.5a, EJ-PS2:13.1±5,2a). In addition, differences in DNA fragmentation index were observed (EJ-CT:2.6±0.6a; EJ-PS1:2.4±0.8a; EJ-PS2:3.0±0.8a; CT:1.4±0.4b; EP-PS1:1.2±0.3b; EP-PS2:1.3±0.2b). It was concluded that the addition of 20% seminal plasma from fertile or subfertile animals prior to the freezing of epididymal spermatozoa from subfertile animals does not interfere in sperm quality.(AU)


Assuntos
Animais , Masculino , Sêmen , Criopreservação/veterinária , Epididimo , Análise do Sêmen/veterinária , Cavalos , Infertilidade Masculina/veterinária
11.
Acta sci. vet. (Impr.) ; 46: 1-6, 2018. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1457810

Resumo

Background: Over the years, the most commonly used extenders for semen cryopreservation contain egg yolk as cryoprotectant. However, more recent studies have used the low density lipoproteins, extract of hen egg yolk which is responsible for the cryoprotective effect. Nevertheless, little was known about its required minimum concentration as well as its interaction with other extra cellular cryoprotectants, like skimmed milk. The present study aimed at investigating the effect of replacing whole egg yolk by adding low density lipoproteins at low concentrations, in TES-Tris-skim milk based extender, on the post-thaw quality of buffalo bull sperm.Materials, Methods & Results: Eighteen ejaculates were collected from six buffalo bulls and diluted with TES-Tris-skim milk based extender containing LDL, extracted from hen egg yolks, at the concentrations of 2%, 4%, 8% and 14%, against a control extender containing 20% fresh egg yolk. After semen collection, analyses of subjective motility, vigor, force tourbillon, sperm concentration (Neubauer chamber) and sperm morphology (phase contrast microscopy) were performed. The diluted semen was packaged in 0.25 mL straws, and cooling was performed on computerized machine (TK 4000®), using a cooling rate of -0.25°C/min to 5°C. Semen was kept in balance at 5°C for 4 h. The straws were frozen in an ice chest, kept at 5 cm from the surface of liquid nitrogen for 20 min and then immersed in liquid nitrogen. The samples were kept in cryogenic container until thawing. Post-thaw kinetic parameters during incubation at 37°C (CASA), sperm membrane integrity (SYBR-14/PI), membrane functionality (hypo-osmotic swelling test) and DNA fragmentation (%DFI - SCSA) were evaluated after thawing. Immediately post-thaw, total motility was higher in the control (56.53 ± 9.73) than in the tested extenders; however, after 30 min the difference was no longer detected.[…]


Assuntos
Masculino , Animais , Bovinos , Criopreservação/métodos , Criopreservação/veterinária , Lipoproteínas LDL/análise , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Citometria de Fluxo/veterinária , Motilidade dos Espermatozoides , Proteínas do Ovo/análise
12.
Acta sci. vet. (Online) ; 46: 1-6, 2018. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-17895

Resumo

Background: Over the years, the most commonly used extenders for semen cryopreservation contain egg yolk as cryoprotectant. However, more recent studies have used the low density lipoproteins, extract of hen egg yolk which is responsible for the cryoprotective effect. Nevertheless, little was known about its required minimum concentration as well as its interaction with other extra cellular cryoprotectants, like skimmed milk. The present study aimed at investigating the effect of replacing whole egg yolk by adding low density lipoproteins at low concentrations, in TES-Tris-skim milk based extender, on the post-thaw quality of buffalo bull sperm.Materials, Methods & Results: Eighteen ejaculates were collected from six buffalo bulls and diluted with TES-Tris-skim milk based extender containing LDL, extracted from hen egg yolks, at the concentrations of 2%, 4%, 8% and 14%, against a control extender containing 20% fresh egg yolk. After semen collection, analyses of subjective motility, vigor, force tourbillon, sperm concentration (Neubauer chamber) and sperm morphology (phase contrast microscopy) were performed. The diluted semen was packaged in 0.25 mL straws, and cooling was performed on computerized machine (TK 4000®), using a cooling rate of -0.25°C/min to 5°C. Semen was kept in balance at 5°C for 4 h. The straws were frozen in an ice chest, kept at 5 cm from the surface of liquid nitrogen for 20 min and then immersed in liquid nitrogen. The samples were kept in cryogenic container until thawing. Post-thaw kinetic parameters during incubation at 37°C (CASA), sperm membrane integrity (SYBR-14/PI), membrane functionality (hypo-osmotic swelling test) and DNA fragmentation (%DFI - SCSA) were evaluated after thawing. Immediately post-thaw, total motility was higher in the control (56.53 ± 9.73) than in the tested extenders; however, after 30 min the difference was no longer detected.[…](AU)


Assuntos
Animais , Masculino , Bovinos , Criopreservação/métodos , Criopreservação/veterinária , Lipoproteínas LDL/análise , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Proteínas do Ovo/análise , Citometria de Fluxo/veterinária , Motilidade dos Espermatozoides
13.
Pesqui. vet. bras ; 37(6): 643-649, jun. 2017. graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-895450

Resumo

Mesenchymal stem cells (MSC) reside in small numbers in many adult tissues and organs, and play an active role in the homeostasis of these sites. Goat derived multipotent MSC have been established from bone marrow, adipose tissues and amniotic fluid. Umbilical cord blood (UCB) is considered an important source of these cells. However, the MSC isolation from the goat UCB has not been demonstrated. Therefore, the aim of the present study was to isolate, culture and characterize goat umbilical cord blood derived mesenchymal stem cells. MSC were isolated from UCB by Ficoll-Paque density centrifugation and cultured in DMEM supplemented with 10% or 20% FBS. FACS analysis was performed and induction lineage differentiation was made to characterize these cells. They exhibited two different populations in flow cytometry, and revealed the positive expression of CD90, CD44 and CD105, but negative staining for CD34 in larger cells, and positive stained for CD90 and CD105, but negative for CD44 and CD34 in the smaller cells. MSC from goat UCB showed capability to differentiate into chondrocytes and osteoblasts when incubated with specific differentiation medium. Present study established that goat mesenchymal stem cells can be derived successfully from umbilical cord blood.(AU)


As células tronco mesenquimais (MSC) residem em pequenas quantidades em muitos tecidos e órgãos adultos, desempenhando um papel ativo na homeostase destes locais. O isolamento de MSC já foi demonstrado em amostras de medula óssea, tecido adiposo e fluido amniótico de cabras. O sangue de cordão umbilical é considerado uma fonte importante desse tipo de células. No entanto, até o presente momento, não foi demonstrado o isolamento de MSC provenientes do sangue de cordão umbilical de cabras. Dessa forma, o objetivo do presente estudo foi isolar, cultivar e caracterizar células tronco mesenquimais provenientes do sangue do cordão umbilical caprino. As MSC foram isoladas utilizando o gradiente de densidade Ficoll-Paque e cultivadas em DMEM suplementado com 10% ou 20% de FBS. A caracterização desse tipo celular foi realizada através de análise por citometria de fluxo e diferenciação em linhagens celulares mesodermais. A analise no citômetro de fluxo demonstrou a presença de duas populações distintas, um grupo com células maiores e outro com células menores; observando expressão positiva de CD90, CD44 e CD105, e negativa para CD34 nas células maiores; enquanto que as menores foram positivas para CD90 e CD105, mas negativas para CD44 e CD34. As células isoladas demonstraram capacidade de se diferenciar em condrócitos e osteoblastos quando incubadas com meio de diferenciação específico. O presente estudo demonstrou que células tronco mesenquimais podem ser obtidas com sucesso do sangue do cordão umbilical caprino.(AU)


Assuntos
Animais , Células-Tronco , Cabras/sangue , Linhagem Celular , Sangue Fetal , Organogênese , Citometria de Fluxo/veterinária
14.
Pesqui. vet. bras ; 37(6): 643-649, jun. 2017. graf, ilus
Artigo em Inglês | VETINDEX | ID: vti-23634

Resumo

Mesenchymal stem cells (MSC) reside in small numbers in many adult tissues and organs, and play an active role in the homeostasis of these sites. Goat derived multipotent MSC have been established from bone marrow, adipose tissues and amniotic fluid. Umbilical cord blood (UCB) is considered an important source of these cells. However, the MSC isolation from the goat UCB has not been demonstrated. Therefore, the aim of the present study was to isolate, culture and characterize goat umbilical cord blood derived mesenchymal stem cells. MSC were isolated from UCB by Ficoll-Paque density centrifugation and cultured in DMEM supplemented with 10% or 20% FBS. FACS analysis was performed and induction lineage differentiation was made to characterize these cells. They exhibited two different populations in flow cytometry, and revealed the positive expression of CD90, CD44 and CD105, but negative staining for CD34 in larger cells, and positive stained for CD90 and CD105, but negative for CD44 and CD34 in the smaller cells. MSC from goat UCB showed capability to differentiate into chondrocytes and osteoblasts when incubated with specific differentiation medium. Present study established that goat mesenchymal stem cells can be derived successfully from umbilical cord blood.(AU)


As células tronco mesenquimais (MSC) residem em pequenas quantidades em muitos tecidos e órgãos adultos, desempenhando um papel ativo na homeostase destes locais. O isolamento de MSC já foi demonstrado em amostras de medula óssea, tecido adiposo e fluido amniótico de cabras. O sangue de cordão umbilical é considerado uma fonte importante desse tipo de células. No entanto, até o presente momento, não foi demonstrado o isolamento de MSC provenientes do sangue de cordão umbilical de cabras. Dessa forma, o objetivo do presente estudo foi isolar, cultivar e caracterizar células tronco mesenquimais provenientes do sangue do cordão umbilical caprino. As MSC foram isoladas utilizando o gradiente de densidade Ficoll-Paque e cultivadas em DMEM suplementado com 10% ou 20% de FBS. A caracterização desse tipo celular foi realizada através de análise por citometria de fluxo e diferenciação em linhagens celulares mesodermais. A analise no citômetro de fluxo demonstrou a presença de duas populações distintas, um grupo com células maiores e outro com células menores; observando expressão positiva de CD90, CD44 e CD105, e negativa para CD34 nas células maiores; enquanto que as menores foram positivas para CD90 e CD105, mas negativas para CD44 e CD34. As células isoladas demonstraram capacidade de se diferenciar em condrócitos e osteoblastos quando incubadas com meio de diferenciação específico. O presente estudo demonstrou que células tronco mesenquimais podem ser obtidas com sucesso do sangue do cordão umbilical caprino.(AU)


Assuntos
Animais , Células-Tronco , Cabras/sangue , Linhagem Celular , Sangue Fetal , Organogênese , Citometria de Fluxo/veterinária
15.
Acta cir. bras. ; 32(11): 984-994, nov. 2017. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-728461

Resumo

Purpose: To investigate the use Aldefluor® and N, N - Dimethylaminobenzaldehyde (DEAB) to design a protocol to sort keratinocyte stem cells from cultured keratinocytes from burned patients. Methods: Activated Aldefluor® aliquots were prepared and maintained at temperature between 2 to 8°C, or stored at -20°C. Next, the cells were collected following the standard protocol of sample preparation. Results: Best results were obtained with Aldefluor® 1.5µl and DEAB 15 µl for 1 x 106 cells, incubated at 37°C for 15 minutes. Flow cytometer range for keratinocyte stem cells separation was evaluated. There were 14.8% of stem cells separated in one sample of keratinocyte culture used to pattern the protocol. After being defined the ideal concentration, the same test pattern was performed in other keratinocyte samples. We observed a final mean of 10.8%. Conclusion: Aldefluor® has been shown as a favorable marking of epidermal keratinocyte stem cells for subsequent separation on a flow cytometer, with detection of 10.8% of epidermal keratinocyte stem cells, in this protocol.(AU)


Assuntos
Humanos , Queratinócitos , Células-Tronco Adultas , Aldeído Desidrogenase/análise , Citometria de Fluxo/métodos , Protocolos Clínicos
16.
Pesqui. vet. bras ; 37(6)2017.
Artigo em Inglês | VETINDEX | ID: vti-743656

Resumo

ABSTRACT: Mesenchymal stem cells (MSC) reside in small numbers in many adult tissues and organs, and play an active role in the homeostasis of these sites. Goat derived multipotent MSC have been established from bone marrow, adipose tissues and amniotic fluid. Umbilical cord blood (UCB) is considered an important source of these cells. However, the MSC isolation from the goat UCB has not been demonstrated. Therefore, the aim of the present study was to isolate, culture and characterize goat umbilical cord blood derived mesenchymal stem cells. MSC were isolated from UCB by Ficoll-Paque density centrifugation and cultured in DMEM supplemented with 10% or 20% FBS. FACS analysis was performed and induction lineage differentiation was made to characterize these cells. They exhibited two different populations in flow cytometry, and revealed the positive expression of CD90, CD44 and CD105, but negative staining for CD34 in larger cells, and positive stained for CD90 and CD105, but negative for CD44 and CD34 in the smaller cells. MSC from goat UCB showed capability to differentiate into chondrocytes and osteoblasts when incubated with specific differentiation medium. Present study established that goat mesenchymal stem cells can be derived successfully from umbilical cord blood.


RESUMO: As células tronco mesenquimais (MSC) residem em pequenas quantidades em muitos tecidos e órgãos adultos, desempenhando um papel ativo na homeostase destes locais. O isolamento de MSC já foi demonstrado em amostras de medula óssea, tecido adiposo e fluido amniótico de cabras. O sangue de cordão umbilical é considerado uma fonte importante desse tipo de células. No entanto, até o presente momento, não foi demonstrado o isolamento de MSC provenientes do sangue de cordão umbilical de cabras. Dessa forma, o objetivo do presente estudo foi isolar, cultivar e caracterizar células tronco mesenquimais provenientes do sangue do cordão umbilical caprino. As MSC foram isoladas utilizando o gradiente de densidade Ficoll-Paque e cultivadas em DMEM suplementado com 10% ou 20% de FBS. A caracterização desse tipo celular foi realizada através de análise por citometria de fluxo e diferenciação em linhagens celulares mesodermais. A analise no citômetro de fluxo demonstrou a presença de duas populações distintas, um grupo com células maiores e outro com células menores; observando expressão positiva de CD90, CD44 e CD105, e negativa para CD34 nas células maiores; enquanto que as menores foram positivas para CD90 e CD105, mas negativas para CD44 e CD34. As células isoladas demonstraram capacidade de se diferenciar em condrócitos e osteoblastos quando incubadas com meio de diferenciação específico. O presente estudo demonstrou que células tronco mesenquimais podem ser obtidas com sucesso do sangue do cordão umbilical caprino.

17.
B. Inst. Pesca ; 43(2): 257-265, abr.-jun. 2017. ilus, graf
Artigo em Português | VETINDEX | ID: vti-16399

Resumo

Avaliou-se a eficiência do choque térmico duplo para induzir tetraploidia em jundiá Rhamdia quelen em diferentes tempos pós-fertilização. Vinte mililitros de ovos (10, 15, 20, 25, 30 e 35 mpf minutos pós-fertilização) foram tratados com choque térmico quente (39±0,2ºC) durante 3 min seguido de choque térmico frio (1,0±0,1ºC) durante 30 min. Um grupo controle foi utilizado. As taxas de fertilização e de eclosão foram medidas 12 hpf (horas pós-fertilização) e 30 hpf, respectivamente. Decorridas 60 hpf, 25 larvas de cada unidade experimental foram fixadas para verificação da ploidia, por citometria de fluxo. A taxas de fertilização foram de 87,83% para o controle e de 23,4%; 28,5%; 30,4%; 20,0%; 30,3% e 36,7%, para os grupos tratados com choque térmico aos 10, 15, 20, 25, 30, 35 mpf, respectivamente. Encontraram-se tetraploides apenas nos grupos de ovos tratados aos 15 mpf e 20 mpf. Este é o primeiro trabalho de indução de tetraploidia em jundiá por choques térmicos quente e frio, o qual possibilitou o aperfeiçoamento dessa técnica.(AU)


The efficiency of double thermal shock to induce tetraploidy in Rhamdia quelen (jundiá) at different post-fertilization periods was assessed. Each test was performed with 20 mL of eggs (10, 15, 20, 25, 30 and 35 mpf minutes post-fertilization) exposed to hot thermal shock (39±0.2ºC) for 3 min, followed by cold thermal shock (1.0±0.1ºC) for 30 min. A control group was also employed. Fertilization and hatching rates were evaluated 12 and 30 hours post-fertilization (hpf), respectively. After 60 hpf, twenty-five larvae from each experimental unit were fixed to verify the ploidy by flow cytometry. Control fertilization rate was 87.83% and reached 23.4%, 28.5%, 30.4%, 20.0%, 30.3%, 36.7% respectively for 10, 15, 20, 25, 30, 35 mpf. Tetraploids were detected only at 15 mpf and 20 mpf. This is the first research of tetraploidy in jundiá obtained by hot and cold shocks, making possible the improvement of this technique.(AU)


Assuntos
Animais , Peixes-Gato , Resposta ao Choque Frio , Tetraploidia , Poliploidia
18.
Bol. Inst. Pesca (Impr.) ; 43(2): 257-265, 17. 2017. 2017. ilus, graf
Artigo em Português | VETINDEX | ID: biblio-1465259

Resumo

Avaliou-se a eficiência do choque térmico duplo para induzir tetraploidia em jundiá Rhamdia quelen em diferentes tempos pós-fertilização. Vinte mililitros de ovos (10, 15, 20, 25, 30 e 35 mpf – minutos pós-fertilização) foram tratados com choque térmico quente (39±0,2ºC) durante 3 min seguido de choque térmico frio (1,0±0,1ºC) durante 30 min. Um grupo controle foi utilizado. As taxas de fertilização e de eclosão foram medidas 12 hpf (horas pós-fertilização) e 30 hpf, respectivamente. Decorridas 60 hpf, 25 larvas de cada unidade experimental foram fixadas para verificação da ploidia, por citometria de fluxo. A taxas de fertilização foram de 87,83% para o controle e de 23,4%; 28,5%; 30,4%; 20,0%; 30,3% e 36,7%, para os grupos tratados com choque térmico aos 10, 15, 20, 25, 30, 35 mpf, respectivamente. Encontraram-se tetraploides apenas nos grupos de ovos tratados aos 15 mpf e 20 mpf. Este é o primeiro trabalho de indução de tetraploidia em jundiá por choques térmicos quente e frio, o qual possibilitou o aperfeiçoamento dessa técnica.


The efficiency of double thermal shock to induce tetraploidy in Rhamdia quelen (jundiá) at different post-fertilization periods was assessed. Each test was performed with 20 mL of eggs (10, 15, 20, 25, 30 and 35 mpf – minutes post-fertilization) exposed to hot thermal shock (39±0.2ºC) for 3 min, followed by cold thermal shock (1.0±0.1ºC) for 30 min. A control group was also employed. Fertilization and hatching rates were evaluated 12 and 30 hours post-fertilization (hpf), respectively. After 60 hpf, twenty-five larvae from each experimental unit were fixed to verify the ploidy by flow cytometry. Control fertilization rate was 87.83% and reached 23.4%, 28.5%, 30.4%, 20.0%, 30.3%, 36.7% respectively for 10, 15, 20, 25, 30, 35 mpf. Tetraploids were detected only at 15 mpf and 20 mpf. This is the first research of tetraploidy in jundiá obtained by hot and cold shocks, making possible the improvement of this technique.


Assuntos
Animais , Peixes-Gato , Resposta ao Choque Frio , Tetraploidia , Poliploidia
19.
Acta sci. vet. (Impr.) ; 45: 1-8, 2017. tab
Artigo em Inglês | VETINDEX | ID: biblio-1457634

Resumo

Background: Milk quality is considered unsatisfactory in Brazil due to factors of a social, economic, cultural, and climatic nature. Mastitis is the main disease that affects dairy herds. Microorganisms of the genus Staphylococcus are the most frequently isolated pathogens in cases of mastitis in bovines. Staphylococcus aureus requires more attention because they have the ability to develop resistance to antimicrobials used in the treatment of mastitis. Thus, the aim of the present study was to evaluate virulence factors in isolates of S. aureus as well as analyze the hygienic-sanitary quality of raw milk produced on dairy farms in a semiarid region of northeastern Brazil.Material, Methods & Results: Samples were taken from milk containers at 44 properties. Fifty-eight isolates of Staphylococcus spp. were analyzed and genotypically identified as S. aureus. In the phenotypic characterization, 56.8% (33/58) of the isolates demonstrated moderate biofilm production. In the genotypic characterization (icaA, icaD and bap genes), icaA was the most representative among the isolates. No resistance to cephalothin or oxacillin was found, but 62% (36/58) of the isolates exhibited resistance to ampicillin, amoxicillin, and penicillin. In the genotypic evaluation in response to β-lactam antibiotics, 50% (29/58) of the isolates exhibited the blaZ gene. Total bacterial counts were determined based on the standard plate count and flow cytometry, for which a significant positive correlation was found (r = 0.61, P < 0.01). The somatic cell count was also performed using flow cytometry and demonstrated that 6.8% (3/44) of the properties had values above one million cells per mL. The analysis of Staphylococcus spp. revealed that 20% (9/44) of the properties had significant counts for the production of staphylococcal enterotoxins. Regarding total coliforms, 56.8% (25/44) of the milk analyzed had counts above 1.0 x 103 CFUs/mL.[...]


Assuntos
Feminino , Animais , Bovinos , Fatores de Virulência , Leite/microbiologia , Qualidade dos Alimentos , Staphylococcus aureus/patogenicidade , Alimentos Crus/microbiologia , Mastite Bovina
20.
Acta sci. vet. (Online) ; 45: 1-8, 2017. tab
Artigo em Inglês | VETINDEX | ID: vti-20296

Resumo

Background: Milk quality is considered unsatisfactory in Brazil due to factors of a social, economic, cultural, and climatic nature. Mastitis is the main disease that affects dairy herds. Microorganisms of the genus Staphylococcus are the most frequently isolated pathogens in cases of mastitis in bovines. Staphylococcus aureus requires more attention because they have the ability to develop resistance to antimicrobials used in the treatment of mastitis. Thus, the aim of the present study was to evaluate virulence factors in isolates of S. aureus as well as analyze the hygienic-sanitary quality of raw milk produced on dairy farms in a semiarid region of northeastern Brazil.Material, Methods & Results: Samples were taken from milk containers at 44 properties. Fifty-eight isolates of Staphylococcus spp. were analyzed and genotypically identified as S. aureus. In the phenotypic characterization, 56.8% (33/58) of the isolates demonstrated moderate biofilm production. In the genotypic characterization (icaA, icaD and bap genes), icaA was the most representative among the isolates. No resistance to cephalothin or oxacillin was found, but 62% (36/58) of the isolates exhibited resistance to ampicillin, amoxicillin, and penicillin. In the genotypic evaluation in response to β-lactam antibiotics, 50% (29/58) of the isolates exhibited the blaZ gene. Total bacterial counts were determined based on the standard plate count and flow cytometry, for which a significant positive correlation was found (r = 0.61, P < 0.01). The somatic cell count was also performed using flow cytometry and demonstrated that 6.8% (3/44) of the properties had values above one million cells per mL. The analysis of Staphylococcus spp. revealed that 20% (9/44) of the properties had significant counts for the production of staphylococcal enterotoxins. Regarding total coliforms, 56.8% (25/44) of the milk analyzed had counts above 1.0 x 103 CFUs/mL.[...](AU)


Assuntos
Animais , Feminino , Bovinos , Staphylococcus aureus/patogenicidade , Leite/microbiologia , Qualidade dos Alimentos , Fatores de Virulência , Alimentos Crus/microbiologia , Mastite Bovina
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