D. L. Harris

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VER nearly half a century numerous workers have considered covariances and/or correlations between genotypic values of relatives and have related these population parameters to more basic parameters descriptive of the Mendelian mechanism of inheritance for diploids and the modes of gene action. FISHER (1918) considered random mating populations and(More)
Fifty years of research in animal breeding and genetics are examined from four perspectives: 1) genetic prediction, 2) animal testing and selection schemes, 3) dissemination of genetic improvement, and 4) definition of breeding objectives in economic form. Breeding in all classes of livestock has moved from a purebred appearance orientation to a performance(More)
Genetic diversity of 35 Psidium guajava L. accessions and three related species (P. guineense Sw., P. sartorianum (O. Berg) Nied. and P. friedrichsthalianum (O. Berg) Nied.) maintained at the U.S. Department of Agriculture (USDA), National Plants Germplasm System, Hilo, HI, was characterized using 20 simple sequence repeat (SSR) markers. Diversity analysis(More)
The shift in perspectives about livestock improvement over a 70-yr period is reviewed. The view changes from livestock improvement as an art, through its becoming a science, to its application as a technology in industry. The use of scientific tools in corporate settings for poultry, dairy, and swine breeding usually involves a strong focus on the economics(More)
Genetic evaluations for the U.S. swine industry are conducted by the eight purebred associations of the National Association of Swine Records. Within-herd evaluations of the growth traits (days to 105 kg [market] and backfat depth) were first reported in 1986. Analyses of the maternal traits (litter size at birth and weaning, and litter 21-d weight) were(More)
A dynamic herd simulation model for a swine production unit has been developed. The model is discrete and stochastic and the appropriate random distributions have been defined from the literature or empirically estimated. Theoretical concepts and relationships presented previously are used to simulate growth and the overall life cycle of individual animals.(More)
Theoretical concepts and relationships used to develop a deterministic computer simulation model of female pigs during their reproductive life are described. The model predicts, in a continuous form, body composition and weight of female pigs, fetal development, sow milk yield, and growth of suckling pigs according to genotype, diet, and management(More)
The Hawk operating system kernel was specifically designed and implemented to support real-time applications on the SANDAC V embedded multiprocessor. The kernel provides a tasking model for program decomposition and supports message passing, synchronization, as well as other ancillary services. The kernel primitives have a Unix™-like system call(More)
Two populations of randombred of different origin (P and Q) containing eight lines (MP, WP, BP, CP, MQ, WQ, BQ and CQ) were used to evaluate the growth, feed efficiency and lifetime performance of females from eight pure lines and 16 F1 crosses. Line comparisons within populations (P or Q) revealed that the heaviest line at days 21, 42 and 63 was W,(More)
The linearized two-dimensional hydrodynamic equations are presented in a maliller n-hich displays the principal assumptions involved. Several approximations are developed for the partial derivatives, and boundary coiiditioiis in finite difference form and the associated errors are discussed. The procedure for establishing a finite difference analog of the(More)