Studying the Nutritive Profile of Guar (Cyamopsis tetragonoloba (L.) Taub.] Harvested at Different Ages and Its Potential as a Summer Forage Legume in Egypt

摘要

THE CURRENT study was carried out at the experimental station of the faculty of agriculture, Alexandria University, Alexandria, Egypt, during the summer of 2013 and 2015. The study aimed to assess the nutritive value of guar cut at three plant ages; 45, 60 and 75 days after sowing (DAS), to be used as alternative animal feed for low quality cereal fodder crops in the summer season in Egypt.Guar harvested at 45 and 60 DAS had higher nitrogen (N) accumulation and lower concentration of cell wall components; especially, neutral detergent fiber (NDF), acid detergent fiber (ADF) and cellulose, showing superior quality compared with that harvested at 75 DAS. On the other hand, the dry matter (DM) content significantly increased with maturity, whereas it was significantly low in plants harvested at 45 DAS (232.54 g kg'1) and 60 DAS (265.87 g kg1) making them not suitable for ensiling. The hay quality indices; namely, relative feed value (RFV), and relative forage quality (RFQ) were also evaluated along the three harvesting ages. Results demonstrated that,despite the statistical significance in RFV and RFQ in favour of the early harvests, all harvests produced hay of similar quality according to the American Forage and Grassland Council (AFGC) for hay quality standards. The three harvesting intervals of guar produced "Grade 1" and "Premium" category hay, with regard to the RFV and RFQ grading, respectively. Guar, in general, is a short duration, drought tolerant, high quality leguminous forage crop, thatcould be grown in Egypt to supply the ruminants with relatively high protein and low fiber feed during the summer season, especially when cut at early age (45 and 60 DAS).