Arias et al., 2003. Livest. Res. Rural Dev., 15 (2)

A study of eight vegetable wastes and sun-cured Lucerne used as forage sources in urban systems of production of milk of the east of Mexico City was carried out to analyze their chemical composition, fractions of the protein and dry matter and organic matter digestibility coefficients. The contents of DM were low in three vegetables (5.7, 7.9 and 8.7% for nopal-legume, lettuce and radish leaf, respectively). The ranges obtained for the crude protein, crude fat and crude fiber went from 4.5 to 27.5%, 0.5 to 2.9% and 11.8 to 27.9% in the same order. The contents of ash were low in the case of the maize cobs (2.1 and 2.7%) and high for the lettuce and radish leaf (28.5 and 30.7%). The protein fractions ranged from 33 to 69% for the soluble protein and 0.4 to 6.2% for the fraction of the non protein nitrogen. The digestibility coefficients of DM and OM ranged from 61.3 to 85.2% and 66.4 to 99.2%, respectively. The OM digestibility was related positively with the crude protein content and in negative form with the fiber content. The low content of DM of most of these feeds is discussed in relation to possible effects upon voluntary intake of dairy cattle.