This study was carried out to determine suitable selection factors for recipients and embryos which could improve pregnancy rates following bovine embryo transfer. The experiment included 52 surgical transfers from February, 1985 through June, 1986 performed on Kyongbuk Breeding Center in southern Korea. The pregnancy rate was highest when recipients were in estrus within 6 hours before the donor to 12 hours after the donor (78.3 % versus 50 % for recipients in estrus earlier or later). Pregnancy rates were acceptable following culture under field conditions for up to 17 hours. More recipients over 15 months of age (76.1 %) remained pregnant than those under 15 months (66.7 %). Embryos transferred during the months from February to July resulted in higher pregnancy rates than those transferred during the remaining 6 months (77.3 % versus 57.1 %). Transferrable embryos were classified A (best) to C (worst); those graded A or B resulted in significantly higher pregnancy rates than those graded C (81.8 % and 73.3 % versus 25.0 %, p0.05). Pregnancy rates among recipients of the Korean native breed tended to be higher than among Holstein recipients (100 % versus 71.1 %). Similarly, when the embryo was transferred to the right uterine horn, pregnancy rates tended to be higher than when it was transferred to the left (81.3 % versus 65 %). Pregnancy rates did not differ according to the stage of development of the embryo; they were for morulae, tight morulae, blastocysts, and advanced blastocysts, respectively : 75.0 %, 66.7 %, 75.0 %, and 77.4 %

This investigation was conducted on 249 Jindo dogs aging from 2 to 12 months to determine body type and external appearance of the dogs. The withers height of male dogs growed rapidly during the period between 2 months and 7 months of age, and was 22.94cm and 49.77cm, respectively. Afterward the growth rate slowed down up to 12 months, 53.33cm. The growth rate of female was similar to male, and the withers height was 22.91cm, 46.81cm, 48.70cm at 2, 6 and 12 months of age. For male and female the body length was 27.21, 27.23cm at 2 months, 51.40cm, 51.62cm at 6 months, 58.33, 52.15cm at 12 months, respectively. Growth rate of the body length was very rapid from 2 to 6 months of age, but afterwards the growth rate was slow and somewhat retarded. For male and female, the withers height to body length ratio was 100 : 109.4 and 100 : 107.1 in 12 months old group. Cross over between the sexes in growth rate occurred between 5.3 to 6.5 months of age for wither height, between 6.0 to 7.2 months for body length, respectively. The average chest girths of male and female were 31.46, 30.46cm at 2 months, 54.92, 52.20cm at 7 months, 60.25, 57.90cm at 12 months, respectively. The growth rate of chest girth was rapid between 2 to 7 months of age and gradual between 7 to 12 months. The average skull lengths of male and female were 11.76, 11.32cm at 2 months, 21.83, 19.60cm at 12 months, respectively. The average head widths of male and female were 8.37, 7.94cm at 2 months, 15.47, 12.46cm at 12 months. Erected type of ear was completed from oblique type at 6 months in male and 7 months in female. On our detailed examinations, we concluded that Jindo dogs completed their growth at 6 to 7 months of age