• Asian-Australasian Journal of Animal Sciences
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• v.17 no.9
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• pp.1227-1231
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• 2004

Pig oocytes contain high levels of lipids in the ooplasm, which reduces the visibility of the germinal vesicle (GV) under microscopic examination. Therefore, the purposes of this study were to investigate the effects of relative centrifugation force (RCF) on the visibility and maturation rates of the GV stage oocytes after centrifugation. In Experiment 1, cumulus-oocyte-complexes (COCs) were collected from slaughterhouse ovaries and randomly allocated to different RCFs (3,000 rpm: 970 g; 6,000 rpm: 3,900 g; or 10,000 rpm: 10,840 g) for 10 or 20 min. Percentages of visible GV were 76-79% in the oocytes centrifuged with 10,000 rpm, which were significantly higher (p<0.01) than those with 3,000 and 6,000 rpm. No significant differences in GV visibility were observed among oocytes with different lengths of centrifugation (p<0.05) regardless of the RCFs. In esperiment 2, the maturation rate of the oocyte was found significantly lower in the 20 min than in the 10 min group received 10,840 g of RCF (30 vs. 75%, p<0.05). In conclusion, the GV of porcine oocytes can be clearly visible by centrifugation at 10,840 g for 10 min without compromising their subsequent maturation rates and a longer centrifugation time (20 min) had no beneficial influence on the visibility of GV stage pig oocytes.

• Korean Journal of Veterinary Research
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• v.29 no.2
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• pp.33-39
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• 1989

Pure separation of various leukocytes is required for the assessment of their roles in immunological and phisiological function. In this study, pure separation of monocytes from canine peripheral blood was attempted. At first, mononuclear cells (PBMC) were separated by ficoll-hypaque gradient method and then monocytes were recovered from PBMC suspensions in sucrose gradient Sol. (PBMC-Sucrose), autologous plasma (PBMC-Plasma) and autologous serum (PBMC-Serum) incubated at $37^{\circ}C$ for 2 hours. 1. In the separation of PBMC by ficoll-hypaque gradient method in canine blood, higher relative centrifugal force (RCF) was required, as high as more than 1,300xg RCF for 40 minutes, for clear formation of PBMC layer than that in human blood as usually used 400xg RCF for 40 minutes. 2. In monocytes-separation from three PBMC suspensions following PBMC separation, recovery-, purity- and viability-rate of monocytes showed better results in PBMC-Plasma and PBMC-Serum than in PBMC-Sucrose suspension, particulary showing better results from PBMC suspensions performed by centrifugation at 1,500xg RCF for 40 minutes.