The purpose of this study was to assess sperm quality during in vitro storage of miniature-pig semen in order to determine which extender should be used and how extender can be diluted for in vitro storage of miniature-pig semen. Freshly ejaculated miniature-pig's semen was diluted with same volumes of Beltsville Thawing Solution (BTS), Androhep, Modena, Mulberry III and modified-Modena extenders. Sperm quality was evaluated by examining viability, motility, abnormality, acrosome intactness, intensity and capacitation status by chlorotetracycline (CTC) staining. Sperm motility decreased with storage period prolonged and differences among BTS, Androhep, Modena and Mulberry III were apparent On Day 1, approximately 80% of the sperm were motile, but motility decreased to 40% at Day 7. During the 7 days of storage, sperm survival in modified-Modena B extender was higher than another extenders. However, it was not differ significantly among other extenders. The percentage of F and B patterns were not differ significantly among the extenders. However, F pattern in modified-Modena B extender was slightly higher until 3 days of storage than that of Modena extender, modified-Modena A extender and modified-Modena C extender. The percentage of AR patterns in modified-Modena B extender was slightly lower, but did not differ significantly among other extenders. The results of present study suggest that modified-Modena B was effective as new extender for in vitro storage of miniature-pig semen.

In the present study, we investigated the effects of genotypes on in vitro maturation and fertilization in porcine fresh/frozen-thawed oocytes. The porcine cumulus-oocyte complexes (COCs) were divided into four groups according to whether they were: (1) in vitro matured; (2) cryopreserved and in vitro matured; (3) in vitro fertilized and (4) cryopreserved, and in vitro fertilized. Maturation of porcine COCs was accomplished by incubation in NCSU23 medium. Immature oocytes were cryopreserved by Open Pulled Straws (OPS) method according to Vajta et al., (1998). Oocytes stained by Acetic-Orcein method were observed under the microscope. DNA extracted from the ovaries was analyzed by RAPD (random amplified polymorphic DNA) and SSCP (single strand conformational polymorphisrrt) method. The rates of oocytes maturation and fertilization were significantly high in AA genotype. The results indicated that in vitro maturation and fertilization in porcine fresh/frozen-thawed oocytes may be affected by genotypes in pigs.