Seasonal Chemical Composition of Saltbush in Semiarid Grasslands of Jordan
In Jordan, Saltbrush (Atriplex spp.) are considered to be a viable solution to the country’s feed shortages when it suffers from drought or experiences dormant seasons. As the gain maturity, most forages will lose their high nutritive value that they have during their early stages of growth. Saltbrush, like most other shrubs, has a high amount of crude protein, phosphorous and calcium throughout the year, properties that are good for animals who need them.
In 1994, it was estimated that Jordan had to supply over 444 thousand tons of supplemented feed for its 2.6 million sheep and one million goats. Found in the salty and arid regions of the Middle East, Saltbrush is a promising solution as a seasonal feed supplement during harsher times in Jordan. However, it had not been properly examined for nutrimental value until scholars used it in their experiments.
Description of the site:
Scientists used the Saltbrush growing in the boundaries of the Jordan University of Science and Technology (JUST) 22 km east of Irbid. The study included three hectares of A. halimus L. which was protected from the attention of grazing animals. Saltbrush here starts growing in December and will cease in April due to hot weather.
Sampling:
Four 100-m transects were randomly selected from the site. Samples were collected on 28 December, January, February, March, April, June, August, and October. At each time, the stems of the Saltbrush were separated and then dried at 70 degrees for a period of 72 hours.
Chemical Analysis:
“One hundred-gram samples of oven-dry leaves and stems from each shrub were milled to pass a 0.4-mm screen and used for subsequent chemical analyses. Calcium was determined by atomic absorptions pec-trophotometer. Phosphorous was deter-mined following Watanable and Olsen (1965) procedures. Crude protein (Nx6.25), nitrogen free extract (NFE) and fiber were determined according to AOAC (1984) procedures”.
The Leaves:
The leaves showed that they held high levels of crude protein, and nitrogen free extract (NFE) during February to April. However, during June to October, the crude protein levels decreased to 15%.
Results:
“Simple linear correlation analysis showed strong positive relationships between P, Ca, crude protein, and nitrogen free extract, whereas fibre exhibited a strong negative correlation with P, Ca, crude protein, and nitrogen free extract. Analyses of variance did not show a significant year effect, however, there were significant differences between leaves and stems and significant seasonal effects in the composition of leaves and stems during the year at P<O.O1”.
Summary:
Saltbrush has proved itself to be a good supplementary item for sheep and goats when the country is experiencing drought.
Bibliography:
Khair, Moh’D., & El-Shatnawi, J. & Mohawesh, Yaser M. (2000) Seasonal Chemical Composition of Saltbush in Semiarid Grasslands of Jordan, Journal of Range Management, Allen Press and Society for Range Management.
