Amino acid profile of chaya and its protein degradation rates in dairy cattle

Abstract

Chaya (Cnidoscolus aconitifolius, family Euphorbeaceae), is a perennial shrub, the leaves of which are eaten by the Mayan people in central America. To explore its potential use as livestock fodder, the amino acid profile and protein degradation rates in fodder chaya containing leaves and succulent stems were analyzed. The amino acid contents (g/100 g protein) in chaya fodder were methionine (0.61), lysine (5.90), arginine (3.62), threonine (2.12), leucine (5.29), isoleucine (3.20), valine (3.73), histidine (1.42) and phenylalanine (4.23). Chaya fodder was rich in lysine, leucine, phenylalanine and valine. The lysine, lucine and valine content in chaya fodder were similar to soybean meal and alfafa hay. Chaya fodder contains 47.7% of rumen undegradable protein which may be useful in high milk producing cattle. In addition, chaya fodder protein solubility in the rumen is 27.95% of CP (Fraction A 5.72% plus Fraction B1 22.23%). Protein Fraction B2, which is intermediately degraded in the rumen, was 33.77% of CP and Fraction B3, most of which escapes degradation was 24.72% of CP. Fraction C, which is unavailable to the animal was 13.56% of protein. This study showed that all the amino acids required to support 10 kg/d of milk production were met by feeding a diet composed solely of chaya fodder.