Efeitos da bioestimulação a laser nas taxas de maturação, fertilização e cultivo de embriões bovinos produzidos in vitro

Abstract

Foram investigados os efeitos da irradiação com diodos lasers operando em 780 nm (infravermelho) e 660 nm (visível) na maturação, fertilização e cultivo in vitro de embriões bovinos. Verificou-se que a irradiação de oócitos com ambos os lasers, durante 30, 60, 120 e 180 segundos (L30, L60, L120, L180) não afetou (p>0,05) as taxas de maturação nuclear (Infravermelho: L30 - 88,92% vs. C30 – 81,84%; L60 – 83,56% vs. C60 – 87,40%; L120 – 76,06% vs. C120 – 85,30%; L180 – 77,42% vs. C180 - 80,16%; e Visível: L30 – 65,81% vs. C30 – 71,59%; L60 – 62,75% vs. C60 – 69,62%; L120 – 70,38% vs. C120 – 64,04%; L180 – 56,72% vs. C180 – 67,41%), e de maturação citoplasmática, avaliada por meio da distribuição dos grânulos corticais (Infravermelho: L30 – 86,18% vs. C30 – 61,04%; L60 – 66,03% vs. C60 – 56,16%; L120 – 53,75% vs. C120 – 79,81%; L180 – 57,70% vs. C180 – 82,04% e Visível: L30 – 81,08% vs. C30 – 74,42%; L60 – 68,11% vs. C60 – 61,63%; L120 – 75,95% vs. C120 – 48,33%; L180 – 77,77% vs. C180 – 59,52%). As porcentagens de produção embrionária ao sétimo dia de cultivo in vitro não foram alteradas (p>0,05) após a irradiação de oócitos com laser infravermelho (L30 – 29,20% vs. C30 – 42,60%; L60 – 32,0% vs. C60 – 31,0%; L120 – 38,0% vs. C120 – 35,0%; L180 – 37,0% vs. C180 – 32,0%), mas foram reduzidas após a irradiação com laser visível durante 180 seg. (L180 – 36,0% vs. C180 – 56,0 %). A irradiação em espermatozóides com ambos os lasers não afetou (p>0,05) as taxas de clivagem ao terceiro dia de cultivo in vitro (Infravermelho: L30 – 90,0% vs. C30 – 95,83%; L60 – 85,56% vs. C60 – 98,33%; L120 – 90,83% vs. C120 – 90,83%; L180 – 89,72% vs. C180 – 97,50%; e Visível: L30 – 82,96% vs. C30 – 85,61%; L60 – 82,10% vs. C60 – 82,53%; L120 – 80,48% vs. C120 – 82,44%;...

The diodo lasers irradiation effects, operating in 780nm (infrared light) and 660 nm (visible light), were evaluated on in vitro maturation, fertilization and culture rates of bovine embryos. Both infrared and visible laser irradiation on oocytes, during 30, 60, 120 and 180 seconds (30, 60, 120, 180) did not change (p>0,05) the rates of nuclear maturation (Infrared: L30 – 88.92% vs. C30 – 81.84%; L60 – 83.56% vs. C60 – 87.40%; L120 – 76.06% vs. C120 – 85.30%; L180 – 77.42% vs. C180 – 80.16%; and Visible: L30 – 65.81% vs. C30 – 71.59%; L60 – 62.75% vs. C60 – 69.62%; L120 – 70.38% vs. C120 – 64.04%; L180 – 56.72% vs. C180 – 67.41%), and the cytoplasmic cortical granule distribution (Infrared: L30 – 86.18% vs. C30 – 61.04%; L60 – 66.03% vs. C60 – 56.16%; L120 – 53.75% vs. C120 – 79.81%; L180 – 57.70% vs. C180 – 82.04% and Visible: L30 – 81.08% vs. C30 – 74.42%; L60 – 68.11% vs. C60 – 61.63%; L120 – 75.95% vs. C120 – 48.33%; L180 – 77.77% vs. C180 – 59.52%). The in vitro embryo production rates measured on seventh day of culture were not changed (p.0,05) after the infrared laser irradiation (L30 – 29.20% vs. C30 – 42.60%; L60 – 32.0% vs. C60 – 31.0%; L120 – 38.0% vs. C120 – 35.0%; L180 – 37.0% vs. C180 – 32.0%), but they were reduced (p<0,05) after the visible laser irradiation during 180 seconds (L180 – 36.0% vs. C180 – 56.0 %). When spermatozoa were irradiated, both lasers did not change the rates of cleavage (p>0,05) on third day of in vitro culture (Infrared: L30 – 90.0% vs. C30 – 95.83%; L60 – 85.56% vs. C60 – 98.33%; L120 – 90.83% vs. C120 – 90.83%; L180 – 89.72% vs. C180 – 97.50%; and Visible: L30 – 82.96% vs. C30 – 85.61%; L60 – 82.10% vs. C60 – 82.53%; L120 – 80.48% vs. C120 – 82.44%; L180 – 83.53% vs. C180 – 87.15%), the embryo production percentages on seventh day ...(Complete abstract, click electronic access below)