Hosein Arzani; Javad Motamedi; Taghi Mirhaji
Volume 25, Issue 3 , November 2018, , Pages 657-670
Abstract
Knowledge of the animal daily requirement in rangelands is one of the essential requirements to calculate the grazing capacity in rangeland plans. In this regard, the daily metabolizable energy requirements of different Sangesary sheep (ewe, ram, and lamb) were investigated. For ...
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Knowledge of the animal daily requirement in rangelands is one of the essential requirements to calculate the grazing capacity in rangeland plans. In this regard, the daily metabolizable energy requirements of different Sangesary sheep (ewe, ram, and lamb) were investigated. For this purpose, according to the average values of forage quality indices and the proportion of species in the plant composition, the amount of metabolizable energy in one kilogram of dry forage at different growth stages was estimated, and considering the daily metabolizable energy requirement, the amount of forage that supplies the animal was estimated. The daily metabolizable energy requirement was calculated according to the proposed MAFF (1984) equation under grazing condition regarding the physical properties of the rangelands, water distribution intervals, plant density, and applying an incremental coefficient of 70%. Based on the results, the amount of forage needed to meet the daily needs of the ewe of the Sangesary sheep with a mean weight of 37 kg in the early, mid, and late growing season was estimated to be 1.6, 2.1 and 2.3 kg dry matter, respectively. The values for adult rams with an average weight of 48.75 kg were estimated to be 1.9, 2.5 and 2.9 kg in different growth stages. The lambs' daily requirement with an average weight of 19.88 kg was estimated to be 1.3, 1.7, and 1.9 in each growing season. The results showed that considering the amount of 1.5 kg of dry matter forage to meet the daily requirements of different kinds of animals grazing in rangelands is not correct and animal requirement need be determined based on forage quality in phenologiacal stages.In addition, the results emphasize that in order to adapt the daily requirements of animal to the forage quality, it is necessary to consider the values of forage quality indices and the proportion of all species grazed in the plant composition, so that the results should not be limited to the species in animal diet. Otherwise, as in the present study, the estimated requirement is more than the daily intake of animal grazing on rangelands.
Daryoush Ghorbanian; Ehsan Zandi Esfahan; Mohamad Amirjan
Volume 23, Issue 1 , June 2016, , Pages 177-187
Abstract
Aellenia subaphylla is a perennial plant species and resistant to drought and salinity, distributed in the winter rangelands and at the margins of the interior deserts such as Damghan desert. In early autumn that available forage is reduced in rangelands, this species produces a considerable forage in ...
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Aellenia subaphylla is a perennial plant species and resistant to drought and salinity, distributed in the winter rangelands and at the margins of the interior deserts such as Damghan desert. In early autumn that available forage is reduced in rangelands, this species produces a considerable forage in addition to a good annual growth. To study the forage quality of Aellenia subaphylla at three growth stages of vegetative, flowering and seeding stages, the branches of 10 species were randomly sampled with three replications. Then the samples were dried and milled. Six forage quality traits including DMD, WSC, CP, CF, ME and ADF were measured. The average of DMD, CP, CF, WSC, Ash, ME, and ADF were estimated to be 35.14%, 17.35%, 40.93%, 13.9%, 6.58%, 3.97 MJ kg-1 dry matter, and 60.45%, respectively. The results of ANOVA and mean comparisons of the traits studied indicated that the forage quality of Aellenia subaphylla was affected by phenological stages. The highest and the lowest CP content were observed at flowering and seeding stages, respectively. The minimum amount of CP for most domestic or wild herbivores for maintenance is reported to be 7.5%. Therefore, this species could supply the CP requirements of livestock. In the flowering stage, ADF and CP increased significantly while a significant reduction was observed in CF, indicating that flowering stage could be recommended for forage utilization. In addition, the average values of DMD, WSC and ME at seeding stage were significantly higher than those of vegetative and flowering stages. Therefore, seeding stage could also be recommended for livestock nutrition. Our results clearly showed that the best time for forage utilization of Aellenia subaphylla, distributed widely in the winter rangelands, was consistent with flowering and seeding stages. On the other hand, this species produces a large amount of seeds, increasing the forage quality at seeding stage. Given that the forage quality of the species studied here was acceptable during flowering and seeding stages, a proper use of this species could be taken into consideration for livestock feed through a sound range management.
Hosein Arzani; Farajollah Tarnian; Javad Motamedi; Morteza Khodagholoi
Volume 21, Issue 2 , August 2014, , Pages 198-207
Abstract
Forage quality is one of the most important factors in determination of the rangeland grazing capacity and also indicates the sufficiency of nutritive requirements of grazing animals. In this research, the samples of range species (including; Acantholimon festucaceum, Andrachne fruticulosa, Artemisia ...
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Forage quality is one of the most important factors in determination of the rangeland grazing capacity and also indicates the sufficiency of nutritive requirements of grazing animals. In this research, the samples of range species (including; Acantholimon festucaceum, Andrachne fruticulosa, Artemisia sieberi, Euphorbia decipiens, Noaea mucronata, Scariola orientalis, Stachys inflate, Stipa Arabica and Stipa barbata) in Maime, which were dominant in region, were collected in three phenological stages (vegetative, flowering and seeding) in three replications, and five individual plants were collected in each replication. Then, plant samples were chemically dissolved to measure the nitrogen (N) and acid detergent fiber (ADF). A split plot in a completely randomized design was used to analyze the data. Results indicated that the mean of effective indices on forage quality had considerable changes in phenological stages and it had significant influence on the forage quality. With progress of growth stages, the amount of crude protein (CP), dray mater digestibility (DMD) and metabolism energy (ME) decreased and the amount of acid detergent fiber (ADF) increased. In addition, results showed that crude protein amounts of all studied species in vegetative and flowering stage swere more than critical level (7%) for need of daily animal requirement and in seeding stage was less than animal requirement. Mean value of dray mater digestibility (DMD) in vegetative stage was more than critical level (50%), and in flowering stage and seeding stage were less than its critical level for need of maintenance. The mean value of metabolism energy in all three phenological stages was less than critical level (8 Mj/Kg/DM) for need of maintenance of single animal unit. This suggests that desirable quality of pasture forage at different grazing times is not same and determination of daily animal unit requirement based on forage quality is needed. In general, the studied ranges are desirable in terms of supplying the required daily crude protein for animal units, grazing in rangelands, but in terms of providing metabolism energy are undesirable.
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.
Hossein Arzani; Javad Motamedi (Torkan); Ali Nikkhah; Hossein Azarnivand; Mehdi Ghorbani
Volume 19, Issue 4 , March 2013, , Pages 557-570
Abstract
Information on animal requirements is essential to calculate rangeland grazing capacity. Therefore, animal weight and animal unit equivalent (AUE) of each breed should be determined independently. In this research, live weight of Kabodeh sheep was determined based on average live weight of 3 and 4 years ...
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Information on animal requirements is essential to calculate rangeland grazing capacity. Therefore, animal weight and animal unit equivalent (AUE) of each breed should be determined independently. In this research, live weight of Kabodeh sheep was determined based on average live weight of 3 and 4 years old ewes. For this purpose, two herds of Kabodeh breed were selected. In each herd, 15 three–year-old ewes, 15 four-year-old ewes, 5 three-year-old rams, 5 four year-old-rams, 10 three-month-old lambs and 10 six-month--old lambs were selected. They were weighed two times including at the time of grazing season in lowland and highland rangelands. For determination of dry matter requirement, forage quality was taken into consideration. According to the results, animal weight for herds (three and four years old ewe) was 52.66±0.86 kg. Therefore, animal unit equivalent (AUE) for rams, ewes, 3 and 6-month-old lambs were 1.07, 1.66, 0.38 and 0.51, respectively. According to MAFF equation (1984), daily metabolizable energy requirement for maintenance condition was calculated 9.89 and 10.60 Mj (including that multiplied by 1.4 and 1.5) by considering condition of rangelands and distances from watering points and plant density in lowland and highland rangelands. Dry matter requirement was calculated 1.98 and1.80 kgbased on forage quality in lowland and highland rangelands.