Publications by authors named "J W Oltjen"

A mechanistic, dynamic model was developed to calculate body composition in growing lambs by calculating heat production (HP) internally from energy transactions within the body. The model has a fat pool (f) and three protein pools: visceral (v), nonvisceral (m), and wool (w). Heat production is calculated as the sum of fasting heat production, heat of product formation (HrE), and heat associated with feeding (HAF).

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Updating the static model by Beckett and Oltjen (1993), we determined that from 1991 to 2019, U.S. beef cattle blue water consumption per kg of beef decreased by 37.

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Till date, with over 137,000 certified members, the most successful rancher educational program has been the Beef Quality Assurance (BQA) program. The BQA program was established in the mid-1990's to improve animal health and welfare with a primary objective to reduce the incidence of injection site lesions by instructing producers to administer injections in the neck only. The present study investigated the drivers of this success to inform future rancher education programs around agricultural sustainability.

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Consumer interest in grass-fed beef has been steadily rising due to consumer perception of its potential benefits. This interest has led to a growing demand for niche market beef, particularly in the western United States. Therefore, the objective of this study was to assess the impact of feeding systems on the change in microbial counts, color, and lipid oxidation of steaks during retail display, and on their sensory attributes.

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Variation in nutrition is a key determinant of growth, body composition, and the ability of animals to perform to their genetic potential. Depending on the quality of feed available, animals may be able to overcome negative effects of prior nutritional restriction, increasing intake and rates of tissue gain, but full compensation may not occur. A 2 × 3 × 4 factorial serial slaughter study was conducted to examine the effects of prior nutritional restriction, dietary energy density, and supplemental rumen undegradable protein (RUP) on intake, growth, and body composition of lambs.

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