The present study was conducted to clarify whether superovulation is inhibited by the administration of the inhibitor of Prostaglandin biosynthesis. 30 prepubertal gilts were injected intramuscularly with hCG (6IU/kg of body weight; kg.b.w.) 72 hours after receiving PMSG (12IU/kg.b.w.). They were injected either Indomethacin (22 gilts) or Mefenamic acid (8 gilts) 24 hours after hCG injection. Ovulation was verified by laparotomy 72 hours after hCG injection. Ovulation rate was 82.9, 39.3, 13.3 and 0.0% in the gilts which were given 0, 0.76, 2.53 and 7.6mg of Indomethacin per kg of body weight, respectively. Ovulation rate was 84.6, 80.9, 63.1 and 21.7% in the gilts which were given 0, 10, 30 and 100mg of Mefenamic acid per kg of body weight, respectively. It is concluded that Indomethacin and Mefenamic acid inhibit dose-dependently the ovulation.

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In this study, daily intake of essentilal amino acids in sow's milk fed to piglets with ad libitum access was determined at 3, 7 and 14 days of age.
Three sows (L, LW, WL) and their litters (31 piglets) were used. Sow's milk intake of piglets was measured from 10:00 to 18:00 (8 hour) at 3, 7 and 14 days of age by weigh-suckle-weigh method. Three times the value of the measured one was defined as daily sow's milk intake. Piglets had no access to creep feed. Milk samples were obtained by an oxytocin injection on the following day of the measurement of milk intake to determine amino acid concentrations of total protein hydrolysate.
Daily sow's milk intake increased as time progressed: 523±218g, 809±215g and 979±182g at the age of 3, 7 and 14 days, respectively. Sow's milk intake per piglet decreased as litter size enlarged. Daily intake of essential amino acids, except for tryptophan, from sow's milk also increased linerly from 15.7g at 3 days and to 23.2g at 14 days of age. Amino acids ratios to lysine of sow's milk in this study well agreed with those in ARC (1981). Average daily gain of 7 days (BW 2.7±0.3kg) and 14 days of age (BW 3.8±0.7kg) were 237±50g and 254±44g, respectively. When the daily gain of piglets is 237g at 7 days and 254g at 14 days of age, requirements for each essential amino acid ranged from 75% to 96% of amino acid requirements in Japanese Standard for Swine (JFSS: 1993). However, threonine requirements of piglets at the age of 7 days and 14 days were 66% and 71%, and they consumed methionine+cystine of 56% and 59% of JFSS, respectively, which were the lowest rates.
In conclusion, the results of this study indicated that when the daily gain of 1-5kg piglet was 200g, the amino acid requirements met those of JFSS, except for threonine and methionine+cystine.

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Selection index based on family information was used to estimate expected genetic gains resulting from selection based on animal model BLUP of breeding values. The breeding objective was to achieve predetermined desired changes for average daily gain (DG), backfat thickness (BF) and litter size at birth (LS). Information for selection was on the candidate's parents and their full and half sibs found in generation F_-1, grand parents and their full and half sibs found in generation F_-2, F_-i was defined as animals in the i^th generation back. The candidate for selection was found in the current generation F_-0. Records from F_-0 to F_-4 were used in the present study. All animals were assumed to have one record for DG and BF and each female animal except those in current generation was assumed to have one record for LS. Each male was mated to 5 females. The number of candidates for selection per litter was varied from 2 to 4. The respective heritabilities of 0.3, 0.5 and 0.1 for DG, BF and LS, with genetic and phenotypic correlations between DG and BF of 0.2 were used. No correlations between LS and DG and BF were assumed. When desired change of DG, BF and LS was 2:2:1, estimated genetic gain of each trait using selection on restricted BLUP was as large as that on two-trait selection index for DG and BF and individual phenotype for LS. When desired change of DG, BF and LS was 1:1:2, estimated genetic gain of LS using restricted BLUP was equal to that using single trait BLUP for LS. Furthermore, if the population was at the optimum for BF, larger genetic gain was expected for DG and LS.

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This experiment was designed to clarify the optimum concentration of the seminal plasma in Modena extender for the liquid storage of boar semen at 10°C.
The sperm rich fraction was collected from 2 Landrace boars. About half volume of the semen was centrifuged to collect the seminal plasma. Washed spermatozoa were suspended to 1×10⁸ spermatozoa/ml with Modena extender that contained either 0, 1, 5, 15, 25, 50 or 75% seminal plasma. As a control the sperm rich fraction was diluted five fold with Modena extender. Each sperm suspension was stored anaerobicaly in 0.5ml microtube for 28 days at 10°C. The motility and progressive of spermatozoa were analyzed on the 1, 7, 14, 21 and 28 days of storage by Hamilton-Thorn Motility Analyzer. Each stored semen was diluted to 3×10⁷ spermatozoa/ml with Modena extender and incubated for 60 minutes at 38°C prior to analysis.
The motility and progressive of boar spermatozoa stored in Modena extender containing 5 to 25% seminal plasma were maintained better than those stored in Modena extender containing 0, 1, 50 and 75% of seminal plasma.
This result indicates that the optimum concentration of the seminal plasma in Modena extender is 5 to 25%. This state can be accomplished by a general method of diluting the sperm rich fraction in the range of 1:3 to 1:10 with an extender.

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