Hosein Arzani; Javad Moetamedi; Seyed Ali Hoseini
Volume 21, Issue 4 , March 2015, , Pages 651-662
Abstract
Knowledge of forage quality is of paramount importance for livestock and rangeland management. For this purpose, the forage quality of range species was investigated in summer rangelands of Saraliabad, Golestan province to meet daily animal unit requirement. In the present study, 12 rangeland species ...
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Knowledge of forage quality is of paramount importance for livestock and rangeland management. For this purpose, the forage quality of range species was investigated in summer rangelands of Saraliabad, Golestan province to meet daily animal unit requirement. In the present study, 12 rangeland species including Achillea millifolium, Agropyron trichophorum, Centurea zuvandica, Crepis khorassanica, Koeleria cristata, Medicago sativa, Poa angustifolia, Taraxacum brevidens, Thymus transcaspicus, Tragopogon graminifolius, Trifolium repens and Artemisia aucheri were sampled at three different phenological stages (vegetative, flowering and seeding) in 2009. In each stage, three samples and for each sample three individuals were cut. Then, forage quality indices were calculated. Results showed that the crude protein values at all growth stages were higher than the critical level (7.0%) to meet daily animal unit requirement. In addition, dry matter digestibility values in vegetative and flowering stages were higher than the critical level (50%) to meet daily animal unit requirement, contrary to the seeding stage. Metabolisable energy values in vegetative stage were higher and in flowering and seeding stages were lower than the critical level (8Mj) to meet daily animal unit requirement. Our results clearly showed that the forage quality of range species varied at different growth stages, indicating that daily animal unit requirement need be determined based on forage quality. The results of this study could be used in determining the daily animal unit requirement in different years since measuring forage quality is costly.
Hosein Arzani; Javad Moetamedi; Hasan Yeghaneh; Hamzeh Ali Shirmardi
Volume 21, Issue 2 , August 2014, , Pages 221-233
Abstract
Being informed about the sufficiency of forage required for the daily need of the animal unit grazing on the rangeland is of paramount importance in animal and rangeland management. Therefore, in the current study, 32 important plant species grazed by animals on semi-steppe rangelands of Karsank in Chaharmahal-o-Bakhtiari ...
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Being informed about the sufficiency of forage required for the daily need of the animal unit grazing on the rangeland is of paramount importance in animal and rangeland management. Therefore, in the current study, 32 important plant species grazed by animals on semi-steppe rangelands of Karsank in Chaharmahal-o-Bakhtiari were sampled during three growth stages (vegetative growth, flowering and seeding). During each stage, three samples were taken and three plant bases were cut for each sample. Having measured the percentage of nitrogen (N) and acid detergent fiber (ADF) of the studied species, the amount of their crude protein (CP), dry matter digestibility (DMD) and metabolisable energy (ME) were determined to know their critical level for meeting animals’ daily requirements. In order to analyze the data, analysis of variance (ANOVA) was used and to observe the within-groups differences Duncan's test was employed. Results showed that the maximum crude protein (23.87%), dry matter digestibility (74.35%) and metabolisable energy (6.73 Mj/Kg/DM) belonged to Bellevalia glauca. The minimum crude protein (9.81%) belonged to Thymus daenensis and the minimum dry matter digestibility (51.38%) and metabolisable energy (6.73 Mj/Kg/DM) were recorded for Asperula molluginoides. The average crude protein for vegetative, flowering and seeding stages were 20.92, 13.03 and 8.89%, respectively, that at all three growth stages, it was higher than its critical level (7.0%) to meet the daily maintenance requirement of an animal unit. Average dry matter digestibility values for the three phenological stages were 62.48, 55.02 and 46.18%, respectively, that its amount was higher than the critical level (50%) for vegetative and flowering stages and was lower than the critical amount at the seeding stage for meeting the daily maintenance requirements of an animal unit. Metabolisable energy in vegetative, flowering and seeding stages were 8.62, 7.35 and 5.85%, respectively, which were higher than the critical level (8Mj) during the vegetative growth and flowering stages and lower than the same critical level at the seeding stage for meeting the daily maintenance requirements of an animal unit. This is an indicator of the fact that desirability of range forage at different grazing times is not the same and it is necessary to determine the daily requirement of animal unit on the basis of forage quality. In general, the studied rangelands are considered to be desirable in terms of supplying required daily crude protein and metabolisable energy for an animal unit. Results presented in this paper are important for livestock and range management in the studied area.