Organic acids have been supplemented to weanling pig diets in an attempt to improve postweaning lag. Organic acids have proved beneficial in improving average daily gain (ADG) and increasing nutrient digestibility (Falkowski and Aherne, 1984; Edmonds et al., 1985; Geisting and Easter, 1985). There has also been interest in acidifying grower pig diets in an attempt to increase ADG and improve fe...

The purpose of this study was to estimate components of variance and covariance for backfat and growth rate in swine tested in central test stations in the United States. Data were collected from 26 central boar test stations from 1984 through 1990. The traits analyzed were backfat adjusted to a 104.5-kg basis and ADG adjusted to a 36-kg on-test weight. Records from 7,951 purebred Yorkshire boa...

Interest in improving feed efficiency in cattle is intensifying. Residual feed intake (RFI), which is the difference between expected intake and that predicted based on energy demands, is now the most commonly used measure of feed efficiency over a given time period. However, RFI, as commonly defined, is independent of growth rate, which may affect its acceptance by industry. Residual BW gain (...

Five experiments (five different locations) with a total of 1,230 pigs (135 pens) were conducted in Minnesota, Missouri and Indiana to study the effects of supplementary bambermycins (2.2 ppm) and tylosin (44 or 22 ppm) in swine diets. The antibiotics were fed during the growing and finishing periods, and effects on rate of gain and efficiency of feed conversion were measured. A significant imp...

Data were received from 24 test stations on 3,999 boars tested in fall 1984 and spring 1985. In an effort to increase the connectedness between stations, one reference sire was selected to produce sons (reference boars) through artificial insemination to be tested in the different stations. Fifty-two reference boars were placed across 17 of the test stations. The performance traits analyzed wer...

Three experiments were conducted using crossbred weanling pigs (7.2 to 8.6 kg; 25 to 29 d of age) to determine the effect on performance and nutrient digestibility of .75% yeast culture (YC) additions to starter diets containing whey or one of two fiber sources. An 18% CP corn-soybean meal basal diet was used in all experiments. In Exp. 1 (n = 192), the addition of YC did not affect ADG, ADFI, ...

Crossbred heifers (n = 120; BW = 368 kg, SD = 39 kg) were used to determine effects of dried distillers grains (DDG) and relative contributions of undegradable intake protein (UIP) and fat (ether extract, EE) in DDG on ADG and forage intake (FI). Heifers rotationally grazed six 3.5-ha, smooth bromegrass paddocks (IVDMD = 65.7%, CP = 20.8%, UIP = 2.17%, DM basis). Heifers were blocked by previou...

We report the identification and fine mapping of QTL for birth weight (BWT), preweaning ADG (PWADG), and postweaning ADG on feed (ADGF) in a commercial line of Bos taurus using an identical-by-descent haplotype sharing method. One hundred seventy-six calves of 12 bulls (9 to 30 male calves from each sire) of the Beefbooster, Inc., M1 line were typed using 71 genetic markers from bovine chromoso...

Records from 2,495 litters and 14,605 Landrace and Large White pigs from two farms, but established from the same base population and run as replicated selection lines, were analyzed. Selection within herd was on estimated breeding values weighted by economic values. Animal models and REML procedures were used to estimate genetic, phenotypic, and environmental parameters for the number of pigs ...

The objective of this thesis is to provide a method and tool to leverage computational resources to empower a systems architect to reason about architectural decisions more comprehensively and effectively compared to traditional approaches. This thesis provides a computational framework for decision support called the Architecture Decision Graph framework. It supports human decision-making by p...