A. Karimi, E. Rowghani, M. J. Zamiri, M. Zahedifar,
Volume 8, Issue 1 (4-2004)
Abstract
An experiment was carried out to determine the effect of substituting alfalfa hay (Medicago sativa) with Gundelia tournefortii hay (a range forage in Fars Province) in the ration of fattening lambs. Alfalfa hay was substituted with Gundelia tournefortii harvested at the final stages of flowering at various ratios (0, 25, 50, 75, and 100% dry matter basis) in the ration of fattening lambs. The rations (iso-nitrogenous and iso-energetic) were pelleted and each ration was fed for 75 days to 12 Shirazi Grey ram lambs with an average age of 136 days. The lambs were slaughtered and their feedlot performance and carcass characteristics were measured. Substituting alfalfa hay with Gundelia tournefortii hay did not significantly affect the mean daily weight gain, feed consumption, feed conversion ratio, dressing percentage, internal fat weight, carcass meat content, or meat DM and CP contents (p>0.05). However, backfat depth was significantly different among various rations (p<0.01). At present costs, the inclusion of Gundelia tournefortii in the ration of fattening lambs seemed to be cost-effective the cost of one kg DM of ration was 1266, 1155, 1050, 924, and 787 Rials for rations 1 to 5, respectively.
M. Akhondi, A. Safarnejad, M. Lahouti,
Volume 10, Issue 1 (4-2006)
Abstract
Drought stress is one of the most important environmental stresses in reduce of growth and plants production. Determination of resistance mechanisms to environmental stress in plant improvement is very important. In order to , experiment with osmotic potentials of PEG (zero (control), -4, -8 & -12 bar) and alfalfa genotypes was done. The selected alfalfa genotypes namely, Yazdi(tolerant), Nikshahri(moderate) and Ranger(sensitive) were grown in hydroponic culture. After 4 weeks, they were harvested in order to determination of proline accumulation and Ca+2, K+ and Na+ concentration. The data showed with increasing of drought stress, proline accumulation were increased, but its rate was different among genotypes and organelles. Concentrations of K+, Na+ and Ca2+ increased with increasing of osmotic stress and there was significant different between genotypes. The K+/Na+ ratio in the shoots and roots of plant was decreased, when drought stress increased. Morphological and biochemical data showed Yazdi genotype was more tolerant to drought stress in compare with studied genotypes.
