The objective of this study was to evaluate the effect of retinol (RT) and retinoic acid (RA) on the in vitro development of pre-implantation goat embryos cultured in potassium simplex optimized medium or synthetic oviduct fluid or cocultured in oviductal cells monolayer either in potassium simplex optimized medium or synthetic oviduct fluid. A total of 2407 cumulus-oocyte complexes were aspirated from 2 to 6 mm ovarian follicles from slaughtered animals. Selected cumulus-oocyte complexes were subjected to in vitro maturation in TCM 199 for 24 h at 39 °C in an atmosphere of 5% (v/v) CO(2) in humidified air. In vitro fertilization was performed in modified defined medium. Eighteen hours after in vitro fertilization, cumulus cells were removed and presumptive zygotes were randomly distributed into experimental groups. In Experiment 1, presumptive zygotes were cultured in potassium simplex optimized medium, potassium simplex optimized medium + RT, potassium simplex optimized medium + retinoic acid, synthetic oviduct fluid, synthetic oviduct fluid + RT and synthetic oviduct fluid + RA at 39 °C in a humidified atmosphere of 5% (v/v) CO(2), 5% (v/v) O(2) and 90% (v/v) N(2). In Experiment 2, presumptive zygotes were cocultured in potassium simplex optimized medium + oviductal cells monolayer, potassium simplex optimized medium + RT + oviductal cells monolayer, potassium simplex optimized medium + RA + oviductal cells monolayer, synthetic oviduct fluid + oviductal cells monolayer, synthetic oviduct fluid + RT + oviductal cells monolayer and synthetic oviduct fluid + RA + oviductal cells monolayer in an atmosphere of 5% (v/v) CO(2) in humidified air. In both experiments, media were partially changed on day 2 after in vitro fertilization and unfertilized oocytes were excluded from the experiment. Embryos were cultured or cocultured for 8 days. In Experiment 1, there was no effect of RT or RA supplementation on the proportion of oocytes that reached the morula or blastocyst stages. By contrast, Experiment 2 demonstrated that the addition of 0.28 μg/ml RT and 0.5 μm RA to the embryo culture media stimulated (p < 0.05) development to the morula and blastocyst stages under the coculture conditions tested. In conclusion, retinoids play an important role in pre-implantation development of goat embryos and can be used to enhance in vitro embryo production.
Experiments were carried out to investigate the beneficial effects of retinyl acetate (RAc) and retinoic acid (RA) on goat oocyte maturation as well as the effects of insulin-like growth factor-I (IGF-I), RAc and RA during embryo culture under chemically defined conditions. In Experiment 1, in vitro maturation (IVM) was performed in a chemically defined basic maturation medium (bMM) supplemented with 0.3 μM RAc or 0.5 μM RA. Presumptive zygotes and embryos (2-4 cells) were cultured in droplets of potassium simplex optimised medium (KSOM); however, none of the embryos reached the blastocyst stage. In Experiment 2, oocytes were matured in bMM + RAc or bMM + RA. Presumptive zygotes and 2- to 4-cell embryos were placed in fresh KSOM droplets supplemented with RAc, RA, IGF-I, RAc+IGF-I or RA+IGF-I. In Experiment 1, addition of RAc and RA to bMM increased (P < 0.05) the proportion of 2- to 4-cell embryos reaching the morula stage as compared to the control. In Experiment 2, supplementation of embryo culture media with retinoids and IGF-I increased (P < 0.05) the proportion of 2- to 4-cell stage embryos developing to the morula and blastocyst stage. Our data demonstrate that goat embryo production in chemically defined media could be improved by exogenous RAc or RA and by the interaction between retinoids and IGF-I, and that goat embryos can be produced in vitro from oocytes following protocols similar to those currently used for cattle.
Raw milk is a food with great consumption and economic value in Brazil. However, is susceptible of contamination by pathogenic bacteria. The aimed of this study was to evaluate the quality of in natura milk based on microbiological in three dairy farms, somatic cells counting (SCC), bacterial counting and his physical-chemical composition. Were made the following microbiological analysis: counting of mesophilic and psychrotrophic bacteria, coliforms at 30 ºC, coliforms at 45 ºC, Staphylococcus spp., Listeria spp., and SCC. The physical-chemical analysis was fat, protein, lactose, total solids, urea, and casein. There was no evidence of Salmonella spp. and Escherichia coli were identified in any samples. In accordance to the microbiological standards established by Normative Instruction 76 only coliforms 30 ºC and 45 ºC counts were above the standards. There was a significant difference (p≤0.05) between the three farms studied regarding most microbiological aspects. Also, was observed difference (p≤0.05) for most of physical-chemical aspects. Overall, the milk produced in the regions of Alagoas State fails to meet just a constant criterion in the current legislation.
Infertility and prenatal mortality are the most important causes of production losses in domestic animals. The presence of pathogenic agents in the female reproductive system of cattle can negatively influence the reproductive performance of the herd. The objective of this study was to isolate, quantify, and characterize the components of the vaginal microbiota of multiparous and nulliparous mongrel cows, focusing on proper health and reproductive management. Samples were collected from 20 healthy animals: 10 nulliparous and 10 multiparous cows. The inoculation was performed simultaneously on four different culture media: BBL CHROM agar Candida, BBL Bile Esculin Agar Slants, Baird-Parker Agar, and MacConkey Agar bile salts. The isolated microorganisms were identified according to morphological and biochemical features. Microorganisms were detected in 80% of the nulliparous and 10% of the multiparous cows, with the following frequency: 88.78% of bacteria had morphophysiological characteristics of Staphylococcus spp., 11.22% of Escherichia coli, and 120 isolated yeast colonies which were identified as Candida tropicalis (69%), C. albicans (24%), and C. krusei. Seventeen isolates of Staphylococcus spp. (53.12%) presented sensitivity to all antimicrobials tested: 65.6% to amoxillin, 46.9% to erythromycin, 71.8% to rifampicin, and 46.9% to tetracycline. The rate of resistance to antimicrobials (MDR) was 0.125. The presence of typical microorganisms was detected. The MDR indicated that the isolates did not show multiresistance, with only two (6.25%) resistant to more than one antimicrobial simultaneously. The bacterial isolates studied were sensitive to the antimicrobial drugs tested, demonstrating the potential for use of these active ingredients.
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