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Associate Professor

Ph.D. - Iowa State University, 1990

Phone: 301-405-8494
Email: rangel@umd.edu

Research Interest:

Current research focus is in improving nutrient retention and reducing nutrient waste in broilers and laying hens through the use of feed additives, feed nutrient changes and ingredient choice. Primary emphasis is on phosphorus and nitrogen reduction in broiler excreta. Work will also be done with retention of trace elements as well as dietary energy.

Studies will be conducted on the use of exogenous enzymes and vitamin D3 metabolites, alone and/or in combination. A research project, with broilers, has been initiated to determine if a specific probiotic mix can increase overall nutrient retention and to look at changes in the gastrointestinal tract associated with the use of the probiotic.

Prior to joining the Animal and Avian Sciences faculty at the University of Maryland, I worked in research in the feed industry with an emphasis on exotic animal nutrition. Nutrient adequacy projects were done with penguins, large cats, black rhinos, finches, canaries, parakeets, cockatiels, conures, African Grey parrots, macaws, and cockatoos.

Other projects involved work with maned wolf cystinuria, iron storage disease with toucans, urea toxicity in ostriches, feeding to maximize productivity and economic income in ostriches and emus, ostrich and emu egg nutrient determinations as indicators of breeder bird nutrient status, effect of protein level on leg problems in ostrich chicks, age changes in digestibility of nutrients in ostriches, age changes in nutrient digestibility in emus, protein requirement for breeding and growth in parakeets, and effect of probiotics in rabbits.

Awards and Honors:
- Medal of Achievement award, Delmarva Poultry Industry, Inc., 2003.
- Membership Recognition Award for exceptional service to the American Ostrich Association, 1996.
- Poultry Science Graduate Student Research Manuscript Award, 1990.
- Iowa State University, Research Excellence Award, 1990.
- David R. Griffith Research Award presented by Iowa State University's Nutritional Sciences Council, 1990.
- Holco Award for Excellence in Research, Iowa State University, 1990.
- The International Award. Faculty Women's Club of Iowa State University of Science and Technology, 1989.
- Graduate Student Research Paper Certificate of Excellence, Poultry Science Association Annual Meeting, 1989.
- Sigma Xi, The Scientific Research Society Iowa State Chapter, 1989.
- Gamma Sigma Delta, Agricultural Honor Society, Iowa State Chapter, 1987.
- Iowa State University Research Excellence Award, 1987.