1. Abd El-Salam H (1985) Grazing capacity per feddan at Omayed grazing area, the northern coastal zone, western to Alexandria. Ph.D. Thesis, Alexandria Univ. p 166
2. Adesogon AT, Givens DI, Owen E (2000) Measuring chemical composition and nutritive value in forages. In: Mannetje L. t’, Jones RM (Eds.), Field and laboratory methods for grassland and animal production research. CABI Publishing, Wallingford, Oxon, p 263-278
3. Al-Kouthayri GR, Hassan AA (1998) Survey of major weeds in Hadramout Valley. Yemen Arab J Plant Protect 16(1):19–26
4. Allen SE (1989) Chemical analysis of ecological materials. Blackwell Scientific Publications, London
5. Anonymous (1975) Energy allowances and feeding system for ruminants. Ministry of Agriculture, Fisheries and Food, Her Majesty’s Stationary Office, Technical Bulletin, London, p 33