Review of Regional Project NE62: Relationship between Genetic Markers and Performance in Dairy Cattle

摘要: Abstract Ten stations have cooperated to utilize genetic markers permit selection of animals at an early age. Data from 47 Holstein herds 1960 1973 included 22,000 lactations, on 8600 cows, 4,800 first lactations with associated marker data, and 30,000 services information both the cow service sire. Genetic were 10 loci for blood groups (A, B, C, FV, J, L, M, S, Z, R′ S′), one locus serum protein (transferrin), four milk ( β -lactoglobulin, α s1 -casein, κ -casein). Production variables yield percentages fat, solids-not-fat, protein. Reproduction data dates service, sire, a conception code. Linkage among caseins was extremely close. Phenotypic frequencies combinations J -lactoglobulin differed significantly expected, there evidence other nonrandom within between systems. Preliminary analysis relationships production in lactation indicated that evaluation effects should be models containing several interactions determine additivity effects. results suggest probability some will economic importance. Analysis reproduction has been started.