In vitro- and in vivo-derived early antral follicles have comparable in vitro follicular growth and oocyte maturation rates in goats.

Recent in vitro follicle culture (IVFC) studies in caprine have yielded lower maturation rates using late preantral follicles compared to early antral follicles. Thus, research focusing on developing stage-specific customized culture systems able to improve the efficiency of IVFC for late preantral follicles are warranted. This study aimed to compare the morphometric features, estradiol production, and gene expression between early antral caprine follicles produced in vitro and in vivo. In vitro-derived early antral follicles were produced after a 6-day in vitro culture of late preantral follicles, while in vivo-derived early antral follicles were yielded immediately after isolation from the ovaries; antral follicles were, thereafter, cultured for 18 days. In vitro-derived antral follicles were cultured either in a medium developed for preantral follicles (PF medium) or in a medium developed for antral follicles (AF medium). In vivo-derived early antral follicles, on the other hand, were cultured in AF medium (Control treatment). Results demonstrated that in vitro-derived antral follicles cultured in PF medium produced higher estradiol concentration, and m-RNA expression for matrix metalloproteinase-9 (MMP-9), and insulin receptor when compared to both in vitro- and in vivo-derived antral follicles cultured in AF medium. Remarkably, in vitro-derived antral follicles cultured in PF medium had similar MII and oocytes ≥110 µm rates compared with in vivo-derived antral follicles (Control treatment). In conclusion, when cultured in a single and appropriate medium (i.e., PF medium), in vitro-derived early antral follicles had comparable oocyte maturation rates to the in vivo-derived early antral follicles.

Methicillin-Resistant Staphylococcus aureus from Brazilian Dairy Farms and Identification of Novel Sequence Types.

The aim of this study was to investigate the phenotypic and genotypic diversity and anti-microbial resistance among staphylococci of dairy herds that originated from Paraiba State, north-eastern Brazil, a region where such studies are rare. Milk samples (n = 552) were collected from 15 dairy farms. Isolates were evaluated for anti-microbial susceptibility by Kirby-Bauer disc diffusion method. Confirmation of methicillin-resistant Staphylococcus aureus (MRSA) was performed using multiplex PCR targeting mecA and nuc genes in addition to phenotypic assay based on PBP-2a latex agglutination. Clonal relatedness of isolates was determined by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) genotyping. Staphylococci were detected in 269 (49%) of the samples. Among these, 65 (24%) were S. aureus. The remaining 204 isolates were either coagulase-negative staphylococci (n = 188; 70%) or coagulase positive other than S. aureus (n = 16; 6%). Staphylococci were cultured in seven (35%) of the 20 hand swab samples, from which five isolates were S. aureus. The isolates were most commonly resistant against penicillin (43%), ampicillin (38%) and oxacillin (27%). The gene mecA was detected in 21 S. aureus from milk and in one isolate from a milker's hand. None of the isolates were resistant to vancomycin. PFGE findings showed high clonal diversity among the isolates. Based on MLST, we identified a total of 11 different sequence types (STs 1, 5, 6, 83, 97, 126, 1583, 1622, 1623, 1624 and 1625) with four novel STs (ST1622-ST1625). The findings show that MRSA is prevalent in milk from semi-extensive dairy cows in north-eastern Brazil, and further investigation on its extent in various types of milk production systems and the farm-to-table continuum is warranted.

Avaliação in vitro da sensibilidade da Corynebacterium pseudotuberculosis frente a diferentes tipos de antissépticos e desinfetantes e determinação de sua curva de crescimento / In vitro evaluation of the susceptibility of Corynebacterium pseudotuberculosis to different kinds of antiseptics and disinfectants, and the determination of its growth curve

O objetivo deste estudo foi avaliar o efeito in vitro de antissépticos e desinfetantes contra a Corynebacterium pseudotuberculosis e descrever a curva de crescimento deste micro-organismo em caldo de infusão de cérebro e coração adicionado de 0,1% de Tween 80 (BHI + T), ao longo de 48 horas. Foram avaliados tintura de iodo a 10%, hipoclorito de sódio a 2,5%, permanganato de potássio a 5%, sabonete líquido antisséptico Aseptol® e álcool etílico absoluto (99,8%), por meio da metodologia da disco-difusão. Um swab estéril foi imerso na suspensão bacteriana produzida e semeado em placa de ágar Mueller-Hinton. Discos estéreis foram embebidos em cada solução a ser testada e distribuídos na superfície do ágar. Os resultados foram obtidos de acordo com o diâmetro do halo produzido ao redor dos discos. Para obtenção da curva de crescimento, colônias isoladas do micro-organismo foram inoculadas em frasco contendo BHI + T. A cada quatro horas, 2 mL eram retirados para medição da massa celular em espectrofotômetro e 1 mL para realização das diluições seriadas, plaqueamento em ágar sangue e contagem de células viáveis. Observou-se que, para a obtenção de uma concentração máxima de C. pseudotuberculosis, próxima a 1.200 x 105 células viáveis/mL, deve-se manter o inóculo sob incubação adequada por um período de 28 a 40 horas. Quanto à prova de sensibilidade, verificou-se que a tintura de iodo a 10%, seguida pelo hipoclorito de sódio a 2,5% e permanganato de potássio a 5%, foram os antissépticos e desinfetantes com maior poder bactericida in vitro contra a C. pseudotuberculosis.

The aim of this study was to evaluate the in vitro effect of antiseptics and disinfectants against Corynebacterium pseudotuberculosis, and to define the growth curve of this microrganism inoculated in brain heart infusion broth plus 0.1% of Tween 80 (BHI + T), for 48 hours incubation. For the susceptibility test, evaluations were made using 10% iodine, 2.5% sodium hypochlorite, 5% potassium permanganate, Aseptol® liquid soap, and absolute ethyl alcohol (99.8%), by way of the disc-diffusion method. A sterile swab was immersed in a bacterial suspension and plated in Mueller-Hinton agar. Sterile discs were immersed in each solution to be tested and distributed on the agar surface. The results were obtained according to the inhibition circle diameter formed around the disc. For the growth curve determination, colonies were inoculated in a bottle containing BHI + T. Every 4 hours, 2 mL was withdrawn to evaluate the cell mass in a spectrophotometer, and 1 mL was taken to perform serial dilutions, blood agar base plating and counting of viable cells. It was observed that in order to reach the maximum concentration of C. pseudotuberculosis, close to 1,200 x 105 viable cells/mL, the inoculum must be maintained at appropriate incubation for a period of 28-40 hours. The sensibility test indicated.