Implicações do uso do extrato de LBD (Lipoproteinas de Baixa Densidade) ou da gema de ovo 'purificada', sobre a motilidade e morfologia espermática no sêmen ovino refrigerado por 24 ou 48 horas

• Autor(a) principal: Falleiros, Marcel Barbosa [UNESP]
• Data de Publicação: 2013
• Outros Autores: Bicudo, Sony Dimas [UNESP], Rodello, Leandro [UNESP], Monteiro, Claudia Dias [UNESP], Sakashita, Sabrina Missae [UNESP], Weiss, Romildo Romualdo
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://revistas.bvs-vet.org.br/rvz/article/view/22960; http://hdl.handle.net/11449/141269
• topic: Low density lipoprotein; Ram; Cooling semen; Lipoproteínas de baja densidad; Ovino; Semen refrigerado; Lipoproteínas de baixa densidade; Ovino; Sêmen refrigerado

The objective was to study the effects of substitution of fresh egg yolk for egg yolk "purified" (EYp) or the extract of low-density lipoprotein (LDL) in extenders on the total motility (TM) and progressive motility (PM), acrosomal retention (AR) and the percentage of sperm tail folded (STF) in sheep semen cooled. Twenty ejaculates from five Dorper sheep were diluted in extender Glycine Yolk Milk (GGL - control), Glycine “purified” Yolk Milk (GGpL) or Glycine Extract Milk (GEL), cooled for 24 or 48 hours and subjected to the test depletion of 120 minutes. Analysis of TM and PM was held in HTMA (IVOS 12) in five moments: M0 - immediately after dilution, M1 and M3 - after refrigeration for 24 or 48 hours respectively, M2 and M4 - after 24 or 48 hours of cooling and incubation for 120 minutes at 37°C. In microscopy of phase contrast, using wet preparations with glutaraldehyde, we assessed the RA and the percentage of the STF at M0 to M4. TM was not affected by chilling time regardless of medium used (P>0.05), but declined (P<0.05) after the cooling / exhaust (M2 and M4). The PM declined by 48 hours regardless of the cooling extender used, obtaining better results using GEL, at the moment (M3), compared to control (P<0.05). The exhaust also decreased the PM after two moments of refrigeration, but in the middle GGpL in M2 showed a value higher than the control (P<0.05). The process of cooling and incubation postcooling is not depreciated substantially the quality of sperm morphology, and in any of the times the mean RA was less than 93.8% and of the STF above 5.4%. The extenders GEL and GGpL preserved unchanged the RA during cooling for 24 or 48 hours. There was a decline after the exhaustion of RA (M2 and M4, P<0.05), but the extender GGpL performed better on the M4 (P<0.05). There was no effect of environment on the occurrence of STF, however the GGpL prevented the increase of the bending of sperm tails at all times studied. Then it's possible to replace the fresh egg yolk by the EYp or the extract of LDL in the extender for cooling GGL sheep semen for up to 48 hours, without altering the parameters of sperm motility and morphology.