Cov txiaj ntsig sustainability ntawm kev siv cov amino acid yog qhov sib npaug. Los ntawm kev ua kom muaj kev txo qis hauv kev noj zaub mov muaj protein ntau thaum tswj lossis txhim kho kev ua tau zoo, cov as-ham no txo qis nitrogen excretion thiab nws cov txiaj ntsig ib puag ncig. Qhov kev noj zaub mov zoo no ua kom zoo nrog cov qauv kev lag luam ncig, hloov pauv cov khoom noj khoom haus zoo dua rau hauv cov tsiaj muaj txiaj ntsig zoo nrog cov pov tseg tsawg. Raws li cov qauv thoob ntiaj teb rau kev tsim cov khoom lag luam txuas ntxiv mus, cov amino acid supplementation tshwm sim los ua cov thev naus laus zis tseem ceeb kom ua tau raws li cov cai tswj hwm thiab cov neeg siv khoom xav tau rau kev tsim cov protein kom ruaj khov.