Essential and sulfur amino acid composition of five commonly fed tree leaves to rabbits in the coastal savannah zone of Ghana

Abstract

Despite the importance of essential amino acids (EAA) as building blocks of protein and the criti-cal role played by sulfur-containing amino acids (SAA) in protein synthesis and functions, there is not much information available on the contents of these amino acids in leaves of trees grown in Ghana and fed to rabbits. The EAA and the major SAA (methionine and cysteine) contents in Moringa oleifera, Gliricidia sepium, Carica papaya and Musa paradisiaca leaves were determined. The EAA contents ranged 0.28 to 2.45% dry matter (DM) for methionine in Gliricidia sepium and leucine in Carica papaya leaves respectively. The total EAA contents ranged from 7.24% to 12.86% DM for Gliricidia sepium and Carica papaya leaves respectively. The EAA contents of crude pro-tein (CP) in the leaves ranged from 1.59 to 8.58% for methionine in Gliricidia sepium and leucine in Musa paradisiaca leaves respectively. The methionine plus cysteine % DM was lowest for Gliri-cidia sepium leaves, and that of total nitrogen was lowest in Musa paradisiaca leaves. The mean methionine plus cysteine and total nitrogen percentage DM in the leaves were 0.68 ± 0.3 and 0.42 ± 0. 1% respectively, whilst the corresponding mean percentage CP were 3.0 ± 0.3 and 1.89 ± 0. 2% respectively. The results obtained in the study suggest that the leaves of the selected trees are good sources of CP, EAA and methionine plus cysteine, and are capable of meeting the requirements of rabbits when fed as sole diets or incorporated into concentrate diets at appropriate inclusion levels.