English

Abstract

This study assessed the effects of storage method and storage duration on the dynamics in nutritional qualities of tef (Eragrostis tef-cereal indigenous to Ethiopia) and wheat straws in Ejere woreda, central highlands of Ethiopia. The trial was designed with a factorial combination of two storage methods (shelter shade, open-air) and four storage durations (zero, two, four and six months). A total of 12 farmers (six conserving tef straw and the rest six conserving wheat straw) were selected for sampling and evaluation of the crop residues. Among the six farmers conserving each of the crop residues, three of them stored the straws in open-air while the other three used shelter shade. All the measured parameters (DM, ash, CP, IVOMD, ME, NDF, ADF and lignin contents) were significantly (p<0.05) affected by storage method and storage durations. The CP, IVOMD and ME contents showed consistently decreasing trends with prolonged storage durations, with higher nutrient losses in straws stored in open air than those stored under shelter. The estimated losses in CP contents during the six months storage period, respectively when stored under shelter and in open air were 30.2 and 41% in tef straw; and 22.3 and 46.9% in wheat straw. Similarly, IVOMD was reduced by 35.8 and 41.1% in tef straw and by 33.3 and 42.6% in wheat straw when stored under shelter and in open air, respectively during the six months storage period. On the other hand, the fiber fractions showed increasing trends with prolonged storage durations, with higher rates of increase in straws stored in open air than those stored under shelter. During the six months storage period, NDF content was increased by 8.5 and 13.6% in tef straw and by 8.9 and 12.9% in wheat straw, respectively when stored under shelter and in open air. The ADF content was increased by 8.4 and 12.2% in tef straw and by 14.9 and 19.3% in wheat straw when stored under shelter and in open air condition, respectively. Lignin content was also increased by 14.2 and 53.1% in tef straw and by 37.7 and 32.2% in wheat straw when stored under shelter and in open air, respectively. The decrease in CP and IVOMD, and the increase in fiber fractions with prolonged storage durations in the crop residues could be attributed to the loss of readily soluble nutrients and the higher concentration of the fibrous materials in the feed DM mainly when stored in open air. The result revealed that quality of crop residues which is inherently low would be substantially reduced further during storage especially when stored in open air. Therefore, supplementation schemes should consider the storage method, storage duration and the associated dynamics in nutritional quality in crop residue-based feeding system of dairy cattle. Key words: Crop residues, nutritional quality, storage method, storage duration, tef and wheat straws.