Test day SCC records were obtained from the Ontario DHI and converted to somatic cell score using a logarithmic transformation. Adjustment factors for stage of lactation and calendar month were obtained for first and later lactations. Effects of stage of lactation were significant and followed a systematic pattern. Seasonal effects were small. Sire estimated breeding values for lactation mean adjusted test day somatic cell scores were obtained from an animal model based on first, later, and all lactations, assuming a heritability of .11 and repeatability of .27. Mean accuracy of estimated breeding values for sires with at least 30 daughters was .64 for first lactation, .76 for second to fifth, and .86 for all lactations. Genetic trends for somatic cell score were not significant. The correlation of breeding values estimated from first lactations with estimates based on later lactations was .62 for sires with at least 50 daughters, which resulted in an approximate genetic correlation of .72. Correlations of sire estimated breeding values for somatic cell score from first lactation with estimated breeding values for milk, fat, protein, fat percentage, protein percentage, and milking speed were .12, .05, .11, -.09, -.02, and .20. Correlations between sire estimated breeding values for somatic cell score and type traits were generally small, but favorable with mammary system, -.13, and fore udder, -.16, and unfavorable with dairy character, .24. Somatic cell score should be considered as an auxiliary trait in dairy cattle breeding programs.

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In recent years, China’s ship transportation has shown a rapid growth trend, and the accidents of ships hitting bridge piers are becoming more and more frequent. In view of the frequent occurrence of ships hitting bridge piers, this paper selects closed-cell aluminum foam as the anti-collision material of the piers, and conducts cumulative horizontal impact tests on the closed-cell aluminum foam protected concrete piers. The aim of the experimental tests was to study the influence of the stress stage, thickness and density change of the closed-cel laluminum foam on the impact damage of the concrete piers. The test results show that under the cumulative impact, the close-cell aluminum foam at the yield plateau stage can reduce the damage of the pier; the suitable thickness and density of closed-cell aluminum foam can slow down the development of pier cracks and reduce the impact damage of concrete piers; the densification, excessive thickness and density of closed-cell aluminum foam will increase the impact damage of the bridge pier.

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