Abstract

Two three week feeding trials tested the effects of dietary soybean trypsin inhibitors (SBTI) and/or DL-ethionine (methionine antagonist) on growth, protein digestibility, and clinical parameters in young male and female Sprague Dawley and Wistar rats. SBTI-fed rats had decreased weight gain, feed efficiency, protein digestibility and increased serum urea nitrogen relative to casein-fed control animals. Ethionine without SBTI also had negative effects. Combination of the two factors resulted in greatest growth deficits and increased serum levels of urea nitrogen, triglycerides, alkaline phosphatase and glutamate pyruvate transaminase. Dietary inadequacy or unavailability of sulfur amino acids in rats fed SBTI and ethionine was suggested by poor growth and serum accumulation of total essential amino acids, methionine sulfoxide, and several amino acid precursors of the methionine transsulfuration pathway. DL-methionine supplementation of diets containing SBTI or SBTI + ethionine or use of a soy protein isolate + ethionine diet (low in SBTI) improved growth and feed efficiency and normalized clinical chemistry parameters and serum free amino acid levels further suggesting that a deficit in supply or availability of sulfur amino acids was a factor in the observed changes.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.