The present invention provides a method for lowering the feed conversion rate in a vertebrate comprising inhibiting the function of secreted protein acidic and rich in cysteine (SPARC), wherein the feed conversion rate is defined as the mass of the feed eaten divided by the body mass gain.本發明係提供一種於脊椎動物體中降低飼料轉換率之方法,其包含抑制富含半胱胺酸的酸性分泌蛋白(secreted protein acidic and rich in cysteine,SPARC)之功能,其中飼料轉換率係定義為(飼料投餵重量)/(體重增加重量)。(無元件符號說明)