Kazem Saedi
Volume 22, Issue 1 , June 2015, , Pages 131-142
Abstract
In this study, samples were collected in several phenological stages (in two growing seasons of 2010 and 2011) to assess the effects of two grazing systems (continuous and short-term) on forage quality of three key range species of Bromus tomentellus, Cephalaria kotschyi and Ferula haussknechtii ...
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In this study, samples were collected in several phenological stages (in two growing seasons of 2010 and 2011) to assess the effects of two grazing systems (continuous and short-term) on forage quality of three key range species of Bromus tomentellus, Cephalaria kotschyi and Ferula haussknechtii in Zardawan ranch, and two species of Bromus tomentellus and Ferula haussknechtii in Baharestan ranch. The grazing systems are short-term and continuous in Zardawan and Baharestan, respectively. The studied traits were dry matter digestibility (DMD), acid detergent fibers (ADF), water-soluble carbohydrates (WSC), ash and crude protein (CP). Near infra-red spectroscopy (NIRS) was used to measure these traits. A combined analysis based on unbalanced completely randomized design was conducted for statistical analysis. Mean comparisons were made by Duncan's multiple range test. Results indicated that for all species, phenological stages affected all studied traits, without any exception, so that the late vegetative growth stage could be recommended as a proper time for livestock entry to the rangeland. In the face of variation sources studied, different species showed different responses. The comparison of species habitats showed that none of forage quality traits of B. tomentellus and F. haussknechtii differed in the two sites studied. The mean of most forage quality traits were similar in the two years. According to the results, short-duration grazing system of the Shagaldari did not affect the measured traits negatively, but continuous heavy grazing caused to decreased forage quality.
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.
Kourosh Behnamfar; Khalil Alemi Saeed
Volume 21, Issue 2 , August 2014, , Pages 260-273
Abstract
Knowledge of digestibility of different plant species and relationship between digestibility and chemical composition of forage is one of the basic requirements in order to qualitative and quantitative management of livestock nutrition in rangelands. This research was aimed to evaluate the changes in ...
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Knowledge of digestibility of different plant species and relationship between digestibility and chemical composition of forage is one of the basic requirements in order to qualitative and quantitative management of livestock nutrition in rangelands. This research was aimed to evaluate the changes in chemical composition of forage during the growth stage and relationship between forage digestibility and forage chemical composition in most important tropical range grasses including Cenchrus ciliaris , Panicum antidotale, Pennisetum divisum and Cymbopogon olivieri. Sampling was replicated every two weeks. Forage quality parameters including CP, WSC, CF, ADF, Ash, and DMD were measure using NIR technique. Results showed that forage quality differed significantly in the studied species and growth stages. According to the obtained results the highest and lowest forage quality was obtained for Cenchrus ciliaris and Pennisetum divisum. The results of correlation between forage quality parameters and growth stages of the studied species showed a significant negative correlation between dry matter digestibility and growth stage progress in the first three species but it was not significant for Cymbopogon olivieri. CP and ash showed a significant negative correlation with the progress of time in all three studied species. However, CF and ADF were positively correlated with the progress of time.
Hosein Arzani; Mohammad reza Sadeghi manesh; Hosein Azarnivand; Ghasem Asadian; Ehsan Shahriari
Volume 15, Issue 1 , January 2008, , Pages 42-50
Abstract
Determination of grazing capacity depends on information about various factors such as forage quality and species nutrient values, and for achieve to ideal animal production information about nutrient value are very important. In this trial, nutrient values of twelve species were to evaluate, that were ...
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Determination of grazing capacity depends on information about various factors such as forage quality and species nutrient values, and for achieve to ideal animal production information about nutrient value are very important. In this trial, nutrient values of twelve species were to evaluate, that were grazed by Mehraban sheep in two phenological stages (vegetative and maturity) in two sites of AghDagh & Galebor at Hamadan province. Forage quality indices as Crude protein (CP), acid detergent fiber (minus Hemicelluloses) (ADF),dry matter digestibility (DMD) and metabolisable energy (ME) were measured respectively. According to the results, significant differences were observed among the species and phonological stages for all measured and calculated forage quality factors (p<0.05). Generally, Information about forage quality factors is essential for animal nutrition management in rangeland and it should be considered in range and animal management designs.