Among the biotechnologies of animal reproduction, gamete cryopreservation has become a well
established biotechnology, although it still presents some obstacles when it comes to the
cryopreservation of oocytes and ovarian tissue. Our objective was to evaluate the effect of the
association of the antioxidant resveratrol with sucrose on the vitrification of ovarian tissue of
pre-puberty heifers and adult cows on the morphology and viability of preantral follicles.
Twenty ovaries obtained randomly from the slaughter line in a local refrigerator, 10 ovaries
from pre-puber heifers and 10 ovaries from adult cows were used, these were fragmented and
distributed to different treatments: control (Co), toxicity (T) and vitrification (V), the toxicity
and vitrification treatments submitted to the following vitrification solutions: Vitrification base
solution (SBV) with 0.25M sucrose (VS), SBV with 10 μM resveratrol (VR) and SBV with
sucrose and resveratrol (VS + R) at the same concentrations, after thawing, the ovarian
fragments were evaluated for morphology and follicular viability by light microcopy and
transmission electron microscopy, respectively. The data of the evaluated variables were
submitted to normality tests using the Shapiro-Wilk, the percentage of normal and degenerate
follicles in the experimental groups were analyzed by the Chi-square test, since variables that
did not pass the normality test submitted to the Kruskall-Wallis test, considering (P <0.05) for
determining differences between treatments (InfoStat Statistical Software INFOSTAT, 2012).
Of the total of 2,610 preantral follicles evaluated, the average percentage of normal and
degenerate was 65.51% and 34.49% respectively. And in the different toxicity and vitrification
treatments and in relation to the adult and pre-pubertal groups there was no difference (p> 0.05).
Secondary follicles differed (p≤0.05) in the control group when compared to primordial and
primary follicles, even though these were presented in a smaller proportion in the different
vitrification treatments in both groups of bovine females. The vitrified ovarian tissue fragments
showed similar results to the fresh control. It can be concluded that natural antioxidant
resveratrol when combined with sucrose contributes to the morphological preservation of pre antral follicles of pre-puberty heifers and adult cows when subjected to the process of
vitrification and reheating.
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