This study was carried out to evaluate the effects of glucose and sodium phosphate on in vitro development of porcine oocytes matured and fertilized in vitro. When the culture medium was supplemented with various concentrations of glucose, the higher proportions (23 and 26%) of oocytes developed to morular or blastocyst stages were at the concentrations of 2.78 and 5.56 mM than 0 (9%; P<0.05) and 11.12 mM (18%). In experiment to evaluate effect of sodium phosphate during in vitro development of porcine oocytes, a significantly (P<0.05) higher proportions of embryos developed to morular or blastocyst stages was obtained with sodium phosphateof 0.28 (25%) and 0.53 (27％) mM than 0 (15%), 1.05 (19%) and 2.10 (10%) mM. On the other hand, when oocytes were cultured in medium with (0.53 mM) sodium phosphate, the proportions of developed embryos were significantly (P<0.05) higher in medium without (29%) that than with (14%) 5.56 mM glucose. However, a higher proportion of embryos developed to morular or blastocyst stages were obtained in medium with (23%) that than without (8%) glucose (P<0.05). The minimum essential medium (MEM) added to the culture medium were higher regardless of presence of sodium phosphate and glucose on the development of embryos. Although sodium phosphate and glucose could support morular and blastocyst development to a limited extend (10∼24%), significantly higher proportion (36%) at morular or blastocyst stages was obtained by MEM adding in the medium with sodium phosphate and glucose. These results suggest that the early development of in vitro fertilized porcine oocytes can be maintained efficiently by glucose and sodium phosphate when they were cultured in medium with MEM.

This study was performed to test the cellulose digestibility using the transgenic pigs harboring cellulose degradation gene D (CelD). After delivered offsprings between normal pig and transgenic swine, DNA was isolated from piglets tail for PCR analysis. In first generation, five out of 65 piglets showed CelD positive. Unfortunately, four CelD-positive pigs were died during growing, but one survived pig was used as a transgenic founder to produce F₁ descendents. Among 3 F₁ transgenic pigs produced, one died and the remaining two pigs were used to test the fiber digest efficiency. An assorted feed was composite of 5％ fiber with other ingredients. The feed of 3 kg per day was provided to the pigs including transgenic founders and littermate controls. The manure quantity was measured daily for a month, and all manures were dried for three days to analysis nitrogen, phosphate and fiber concentrations. The fiber digestion efficiencies of the transgenic F₁ pigs showed approximately 10％ higher than those of control pigs. Fiber digestion was not greatly improved in transgenic pigs as it had been expected approximately 30％. Nitrogen concentration of transgenic pig′s manure was slowly decreased compare to the control pigs. Because there were only two transgenic pigs tested, a large number of transgenic pigs may be necessary to obtain more reliable data. Breeding of animals to obtain sufficient transgenic pigs subjected for a further study is on progress. Taken together, this study demonstrated successful production of transgenic pigs with increase of cellulose digestibility in the porcine feed.