[in Japanese]

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In order to clarify the influence of anemia on mineral metabolism of piglets, changes in iron, copper, zinc and manganese contents of the liver during the nursing period were investigated using eighty-six pigs. At 3 days of age, pigs were divided into iron-dextran injected (100mg iron, 18pigs) and uninjected (27pigs) groups within litters. Pigs were killed by bleeding at birth, 1, 3, 10, 20, and 30 days of age. The tissue iron, copper, zinc and manganese were determined by atomic absorption spectrophotometry.
1. At birth, iron contents in the liver and total hemoglobin circulating in body were 6.4 and 45mg, respectively. Calculated from the increase of total hemoglobin circulating in body from birth to 30 days of age, the daily iron requirement of pigs was 7-10mg. Accordingly, iron content in the liver at birth cannot meet even the daily iron requirement of pigs.
2. Iron concentration in the liver at birth and 1 day of age persisted at a high level and varied markedly between and within litters. From 3 days of age, liver iron was decreased markedly. There was a time lag between the rapid decreases of hemoglobin concentration in the blood and liver iron. This indicates that, due to the increase of blood volume resultant from ingesting coloctrum, marrow activity was increased rapidly, and thereafter iron was released from the liver to the circulating system. Of the minerals stored in the fetal period, in particular, iron was selectively mobilized. The sign of iron deficiency from hematological parameters were relatively slower as compared with the depletion of the liver iron. By the depletion of the liver iron, the relationships between growth and anemia became clearer.
3. By iron-dextran injection, iron level in the liver was elevated rapidly at 10 days of age. Although iron concentration in the liver decreased consistently to 30 days of age, hemoglobin concentration was maintained at nearly it's original level.
4. No influence of anemia was observed on copper content in the liver during the neonatal period. From 3 days of age, however, copper concentration in the liver was reduced linearly until 30 days of age when it reached one third of that at birth. This indicates that, in the late nursing period, copper supply from sow's milk was rather deficient for pig's copper requirement.
5. No effect of anemia in piglets on zinc and manganese contents in the liver was observed throughout the experiment period.

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Both the phenotypical and genetical correlation matrixes of Large White (LW), British Landrace (BL), and Middle White (MW) pigs were analysed by a succesive factor varimax rotation of principal composites resulting more interpretable positions.
In the phenotypical correlation matrixes, twenty-three of the thirty-two traits of LW were vectorized into seven composite variables, in BL, eleven of the twenty-six traits into three composites, and in MW, twelve of the fourteen traits into five composites. In the genetical correlation matrixes, thirty-one of the thirty-two traits in LW were vectorized into seven composite variables, in BL, twenty-five of the twenty-six into eight composites, and in MW, twelve of the fourteen traits into five composites.
The composite variables may be used as a source of information on the phenotypical associated groups and the genetical correlated groups among the economic traits of the pigs tested.
In addition, the analyses clearly revealed a pattern of correlated groups among the traits belonging to these three breeds.

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