Life Sciences Commons^™

Genetic Correlations Among Sex-Limited Traits, Michael D. Macneil

Electronic Theses and Dissertations

Monte Carlo simulation techniques were used to assess the merits of three methods for calculation of the genetic correlation when traits have been measured on half-sibs of each sex. The restricted maximum likelihood, path coefficient and covariance component estimators did not differ significantly in their accuracy. Path coefficient and covariance component methodologies gave nearly unbiased estimators for traits of high heritability. Across both levels of heritability, the restricted maximum likelihood methodology resulted in genetic correlations being estimated with significantly smaller sampling variance than the other methods. Genetic correlations were estimated for age of puberty, weight at puberty, conceptions per service, …

Feeding Value Of High Starch And High Fat Rations For Dairy Calves, G. Duff Stewart

Electronic Theses and Dissertations

Sixty-four Holstein calves were used in a 3 x 2 factorial experiment of 12 wk to evaluate growth performance when fed control, high starch, and high fat pelleted diets separately or with a supplemental concentrate mix offered the first 6 wk. High starch and high fat diets were formulated to .contain more digestible energy than the control diet. Calves received milk the first 5 wk, plus one of the above rations ad libitum wk 1 thru 12. The control diet contained corn, oats, and soybean meal; the high starch diet contained corn and soybean meal; while the high fat diet …

Assessment Of The Impact Of The European Corn Borer At Three Locations In South Dakota, David R. Raemisch

Electronic Theses and Dissertations

The European corn borer (Lepidoptera: Pyralidae) varies as an

economically significant pest in South Dakota from south to north. In

the northern part of the state the European corn borer (ECB) is limited

to one generation per year. In contrast, there are localized sites

along the Missouri River in southern South Dakota which usually

experience a substantial second brood population. Infestation by

either first or second brood ECB occurs at different stages in the

developmental sequence of the corn plant. As such, each brood must be

considered separately when assessing relationships between yield loss

and ECB larval cavities within the …

Dye Marking Of Antibiotics Used In Treatment Of Mastitis In Dry And Lactating Cows, Richard A. Ellefson

Electronic Theses and Dissertations

Mastitis is the one major disease affecting dairy cows; considerable direct and indirect economic losses can be attributed to mastitis (6). Treatment of mastitis with antibiotic preparations will alleviate most disease symptoms. Problems may arise when cows treated with antibiotics have their milk used for commercial milk processes before antibiotics are clear. They are: 1) some people are allergic to penicillin, and 2) cultured dairy products may not grow because of inhibition. The Food, Drug, and Cosmetic Act established that milk and milk products containing antibiotics are considered adulterated. Due to recent innovations in antibiotics testing The National Conference on …

Use Of Dry Whey And Lactose Hydrolysis In Yogurt Bases, Nagendra P. Shah

Electronic Theses and Dissertations

Yogurt is one of the oldest and most traditional fermented dairy products. Since early times it has been an important food item of the people in the Middle East. Except for its refreshing taste and wholesomeness as a food, no special virtues were claimed for it until early in the 20th century when the bacteriologist, Elie Metchnikoff, who shared a Nobel Prize in 1908, concluded from his studies on the effect of lactic acid bacteria of the digestive tract, that yogurt arrests putrefaction in the intestinal tract and thus might be beneficial to health (55). Attempts to popularize yogurt in …

Whey-Caseinate Blends And Lactose Hydrolysis In Yogurt Manufacture, Catherine A. Whalen

Electronic Theses and Dissertations

Yogurt is a highly nutritious cultured dairy product which has been consumed for centuries, particularly in Eastern Europe. Although per capita consumption in the United. States is still far below that of most European countries; yogurt sales in the U.S.A. have increased phenomenally during the past three decades. Yogurt sales in the U.S.A. totaled 7.7 million kg in 1955; 31.8 million kg in 1966; and approximately 227 million kg by 1976 (41). Per capita sales increased 211% from 1970 to 1980 (45). Yogurt is generally manufactured from milk or lowfat milk which has been fortified with extra milk solids. Nonfat …