Uso de sondas fluorescentes e ensaio de ligação a ovócitos heterólogos e a membrana perivitelínica de ovo de galinha (Gallus gallus) para a avaliação de espermatozoides frescos e descongelados de jaguatirica (Leopardus pardalis)

• Autor(a) principal: Araujo, Gediendson Ribeiro de
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/5096
• topic: Sondas fluorescentes; Reprodução assistida; Felinos silvestres; Fluorescent probes; Assisted reproduction; Wild felines; CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA::REPRODUCAO ANIMAL

Ex situ conservation strategies aim to assist in maintaining a genetically viable population through strategies of assisted reproduction and cryopreservation of genetic resources. We aimed to validate the combination of fluorescents probes and the egg-sperm binding assay using cryopreserved oocytes in the qualification of fresh and frozen-thawed ocelot semen. Were used three captive ocelots for semen collection by electroejaculation. The semen was evaluated by conventional tests routine. Through those tests (motility and sperm progressive motility, hypoosmotic sweling test and morphology) a decrease (p <0.05) of the quality standards of the frozen-thawed semen compared to fresh semen was observed. The combination of the probes propidium iodide, Hoechst 33342 and Pisum sativum Agglutinin lectin conjugated to fluorescent (FITC-PSA) allowed the identification of sperm subpopulations according to the specific location of cell damage and at the same time allowed a more accurate detection of the deleterious effect of semen cryopreservation in ocelots. The use of cryopreserved oocytes of domestic cats allowed the observation of a decreasing on the binding capacity (p <0.05) of frozen-thawed sperm compared to fresh ocelot spermatozoa, and there was a correlation between total binding in fresh semen with the quality standards in frozen-thawed semen. The combination of fluorescent probes used and the use of sperm-egg binding assay were more specific and reliable in detecting the decrease in ocelot s sperm quality after thawing. The ocelot sperm were also able to bind the perivitelline membrane, in both treatments. Although there is no difference in the amount of bound sperm in treatments (p>0.05), there was a positive correlation (r=0.91; p<0.05) between they. Correlation was also observed between bound sperm to periviteline membrane, in fresh and frozen=thawed semen, and bent tail spermatozoa in frozen-thawed semen (r=0.81; p<0.05 and r=-0.86; p<0.05, respectively). There was correlation (r=-0.71; p<0.05) between the proportion of tightly bent tail (major defect) and the bound sperm to periviteline membrane, both in frozen-thawed semen. Although ocelots spermatozoa have bound satisfactorily to periviteline membrane, the small number of sample could not demonstrate correlation with the sperm fertility. However, the device developed for the membrane allowed the upkeep of its stretch during processing and defined an evaluation area. Thus, futures studies, with a larger sample are needed for effective validation of this technique.