QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Poor, C. L. Articles by Erdman, J. W. Search for Related Content PubMed PubMed Citation Articles by Poor, C. L. Articles by Erdman, J. W., Jr.

Evaluation of the Preruminant Calf as a Model for the Study of Human Carotenoid Metabolism^1,2,

Christopher L. Poor^*, Tiffany L. Bierer, Neal R. Merchen^*,,, George C. Fahey, Jr.^*,,, Michael R. Murphy^*,, and John W. Erdman, Jr.^*,,3

^* Division of Nutritional Science Department of Food Science Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, IL 61801

This study evaluated the preruminant calf as an animal model for the study of human carotenoid metabolism. Fifteen newborn male Holstein calves were fed a carotenoid-free milk replacer diet to maintain them in the preruminant state. After a 7-d adjustment period, three calves were killed and 12 calves received a single oral dose (20 mg) of ß-carotene in the form of water-soluble beadlets. Blood samples were collected periodically and samples of various tissues were collected when the calves were killed. Three animals each were killed by exsanguination at 1, 3, 6 and 11 d post-dosing. Serum ß-carotene concentrations peaked between 12 and 30 h post-dosing and declined slowly afterwards. Serum data were fitted to a two-compartment model and yielded an elimination constant (k₂) that was similar to reported human values. Adrenal tissue showed significant concentrations of ß-carotene by 24 h post-dosing, and levels were still elevated at 264 h. Liver, spleen and lung ß-carotene concentrations were significantly elevated by 24 h and rapidly declined thereafter. Adipose and kidney peak ß-carotene concentrations were observed at 72 and 144 h, respectively. Heart and muscle did not display significant changes in ß-carotene concentrations. The preruminant calf shows promise as an animal model for the study of absorption and metabolism of carotenoids by humans.

KEY WORDS: • beta-carotene • calves • vitamin A • absorption kinetics • animal models

¹ Supported by Cooperative State Research Service-USDA under agreement #89-37200-4452.

² Portions of this work previously reported in: Poor, C. L., Bierer, T. L., Gugger, E. T., Merchen, N., Fahey, G. C., Jr. & Erdman, J. W., Jr. (1990) The pre-ruminant calf and the ferret as models for the study of human carotenoid metabolism. FASEB J. 4(4): A1055 (abs. 4577), and Poor, C. L., Bierer, T. L., Merchen, N., Fahey, G. C., Jr. & Erdman, J. W., Jr. (1991) ß-Carotene concentrations in tissues of pre-ruminant calves following a single oral dose of ß-carotene. FASEB J. 5(5): A1322 (abs. 5517).

³ To whom correspondence should be addressed.

Manuscript received 19 April 1991. Revision accepted 29 July 1991.