An animal experiment was carried out with piglets in order to make clarify the effects of iron administrations on vitamin B₁₂ contents in blood, body weight, and other characteristics of blood. The experiment was comprised of two treatments; muscle injection of iron administrations with vitamin B₁₂ and without vitamin B₁₂ under the control condition, no injections of iron administrations were provided. As a result, it was suggested that the iron administrations with vitamin B₁₂ reinforce the effects of the anti-anemia and increase the body weight.

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We conducted five rearing experiments with 259 finishing pigs to determine the effects of wet/dry feeding on the growth, feed conversion, variations among the herds, and the quality of carcasses. Effects of feeder types were tested across four sections with different feeders: Conventional ad lib hoppers (control section), ledge type wet/dry feeders of Company A and Company B (wet/dry feeder sections A and B), and nose operated flap type wet/dry feeder of Company C (wet/dry feeder section C). Effects of the number of pigs per single feeding space were also examined by pooling the wet/dry feeder sections.
Effects of the feeder type on the average daily gain (DG) of the finishing pigs were not significantly different across the sections, although the superior results were obtained for the wet/dry feeder sections compared with the control section. While the improvement of DG was not observed in the castrated hogs, it was clearly observed in the females. As for the feed conversion, significant effects were obtained in the wet/dry feeder sections, showing the improvement of 6-9% throughout the period of the experiment. As for the change of the variations in weight among the herds, a tendency was observed that in the wet/dry feeder sections, the variations in the weight became small, compared to the variations in the control section, as the pigs gained weight.
The number of pigs per single feeding space in the wet/dry feeder sections had significant effects on the DG. The DG decreased as the number of pigs per single feeding space in the wet/dry feeder sections was increased.
The back and belly fat of the carcasses were thinner in the castrated hogs but thicker in the females in wet/dry feeder sections compared to those in the control section, although these differences were not statistically significant.

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“Restricted best linear unbiased prediction” (RBLUP) with genetic gains of traits restricted by desired levels and “linear programming (LP)”, which maximize an aggregate genotype (H) under the proportinal restriction on genetic gains of traits, based on estimated breeding values (EBV) and frequency of mating were compared. And these selection methods with restricted genetic gains were compared with that for H based on multi-traits best linear unbiased prediction with an animal model (MBLUP). The traits considered were daily gain (DG) and backfat thickness (BF). Selection of the best ten from 30 boars in 1st generation of a closed herd of swine in Kumamoto was examined in alternative selection methods. The results obtained were summarised as follows: 1) The fixed effects were not estimated in RBLUP and RBLUP of breeding values were proportional in every boar. 2) Eighty percent of the boars selected by RBLUP, and 70% of the boars selected by MBLUP were selected also by LP. 3) The average of H in the boars selected by RBLUP and LP under the proportional resteiction on genetic gains of traits were respectively 55% and 71% of H in the ones selected by H based on MBLUP. From these results, it is concluded that the selection method with LP based on EBV is equivalent to RBLUP and is usuful for a closed herd in swine in case of need for restrictions on genetic gains of traits.

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