Go to Top Go to Bottom
Asian-Australas J Anim Sci > Volume 24(10); 2011 > Article
Poultry and Laboratory Animal Nutrition
Asian-Australasian Journal of Animal Sciences 2011;24(10): 1417-1424.
DOI: https://doi.org/10.5713/ajas.2011.11030    Published online August 24, 2011.
Effects of Dietary Protein and Threonine Supply on In vitro Liver Threonine Dehydrogenase Activity and Threonine Efficiency in Rat and Chicken
C. W. Lee, Y. J. Oh, Y. S. Son, W. G. An
Abstract
This study was conducted to assess the relation between threonine (Thr) oxidation rate and threonine efficiency on rat and chicken fed with graded levels of protein and threonine. The increase in threonine content from 0.28 to 0.72% in a diet containing 12.0% crude protein (CP) caused a gradual increase in threonine dehydrogenase (TDG) activity in rat liver. Similar, but more pronounced results were observed after 18.0% CP in the diet. Both protein levels in combination with the highest level of threonine supplementation increased liver TDG activity significantly, indicating enhanced threonine catabolism. Parameters of efficiency of threonine utilization calculated from parallel nitrogen balance studies decreased significantly and indicated threonine oversupply after a maximum of threonine supplementation. At the lower levels of threonine addition the efficiency of threonine utilization was not significantly changed. In the chicken liver up to 0.60% true digestible threonine (dThr) in the 18.5% CP diet produced no effect on the TDG activity. However, TDG activity in the liver was elevated by the diet containing 22.5% CP (0.60% dThr) and the efficiency of threonine utilization decreased, indicating the end of threonine limiting range. In conclusion, the in vitro TDG activity in the liver of rat and growing chicken has an indicator function for the dietary supply of threonine.
Keywords: Threonine Oxidation; Threonine Efficiency; Threonine Dehydrogenase; Liver of Rat and Chicken


Editorial Office
Asian-Australasian Association of Animal Production Societies(AAAP)
Room 708 Sammo Sporex, 23, Sillim-ro 59-gil, Gwanak-gu, Seoul 08776, Korea   
TEL : +82-2-888-6558    FAX : +82-2-888-6559   
E-mail : jongkha@hotmail.com               

Copyright © 2019 by Asian-Australasian Journal of Animal Sciences. All rights reserved.

Close layer
prev next