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71.
Christopher D. Morhart Gerry C. Douglas Christian Dupraz Anil R. Graves Michael Nahm Pierluigi Paris Udo H. Sauter Jonathan Sheppard Heinrich Spiecker 《Annals of Forest Science》2014,71(5):527-542
Context
Current production from natural forests will not satisfy future world demand for timber and fuel wood, and new land management options are required.Aims
We explore an innovative production system that combines the production of short rotation coppice in wide alleys with the production of high-value trees on narrow strips of land; it is an alternative form of alley cropping which we propose to call ‘alley coppice’. The aim is to describe this alley coppice system and to illustrate its potential for producing two diverse products, namely high-value timber and energy wood on the same land unit.Methods
Based on a comprehensive literature review, we compare the advantages and disadvantages of the alley coppice system and contrast the features with well-known existing or past systems of biomass and wood production.Results
We describe and discuss the basic aspects of alley coppice, its design and dynamics, the processes of competition and facilitation, issues of ecology, and areas that are open for future research.Conclusion
Based on existing knowledge, a solid foundation for the implementation of alley coppice on suitable land is presented, and the high potential of this system could be shown. 相似文献72.
Uttarani Maibam Sohan Vir Singh Anil Kumar Singh Suresh Kumar Ramesh Chandra Upadhyay 《Tropical animal health and production》2014,46(7):1155-1160
To evaluate difference in the expression of skin color genes (melanocortin 1 receptor (MC1R) and premelanosome (PMEL)) in lymphocytes during winter and summer season and their correlation with tyrosinase enzyme and cortisol, ten Karan-Fries heifers were selected from National Dairy Research Institute (NDRI) cattle farm. Blood samples were collected from the animals during winter (THI?=?60) and summer (THI?=?83) season at weekly intervals. Relative MC1R and PMEL messenger RNA (mRNA) expression of Karan Fries cattle was found to be significantly (P?0.01) higher during winter than summer. Similarly, tyrosinase activity during winter was found to be significantly (P?0.01) higher than summer season. However, plasma cortisol level was significantly (P?0.01) higher during summer than winter. Thus, expression of the skin color genes showed positive correlation with tyrosinase enzyme, but negative correlation with cortisol level. Expression of MC1R and PMEL in lymphocytes and tyrosinase activity of Karan Fries cattle was highly reduced during summer. The present study showed that the ability of Karan Fries cattle to protect themselves from the harmful radiation of sunlight by melanization decreased with increased heat stress on them. 相似文献
73.
Zelealem Tesfay Gebretsadik Anil Kumar Anal 《Tropical animal health and production》2014,46(2):341-347
A study was conducted in Tigrai, Northern Ethiopia to describe the sheep breeds and their production system. The survey was done in selected districts known for their high sheep population density. The phenotype characterization identified distinct features for each breed. The breeds are Aberegelle, Ille, Begait, and the common Tigrai highland sheep. The strong discriminating phenotypes are face profile, tail type, and compactness; accounting for 83.48, 17.95, and 2.93 % respectively of the total variability among breeds. The flock structure are affected by the market demand; requirements of breeding females and feed availability. Farmers tend to keep more female sheep for longer (culling age of 5.9?±?0.4 and 1.9?±?0.5 for females and males, respectively) for the reasons of feed shortage and need to maximize number of breeding female. The ratio of male to overall female is large (1:6) and thus a single ram gets maximum contact time with ewes and ewe lambs. The overall average age at puberty for females is 9–14 months. However, the presence of very young lamb rams and uncontrolled mating system lead to early breeding of females which results in low conception rate, low birth weight, poor survival rates, and in extreme cases causing inbreeding. It was also possible to identify the critical control points such as breed, age of animals, nutrition, and feeding systems affecting the provision of live animals for good meat quality. 相似文献
74.
C Feltrin CA Cooper N Mohamad‐Fauzi VHV Rodrigues LH Aguiar S Gaudencio‐Neto LT Martins CEM Calderón AS Morais IS Carneiro TM Almeida ING Silva JL Rodrigues EA Maga JD Murray AB Libório LR Bertolini M Bertolini 《Reproduction in domestic animals》2014,49(4):648-656
The presence of the zona pellucida has been perceived as a requirement for the oviductal transfer of cloned embryos at early stages of development while protecting the embryo from an immune system response. We hypothesized that steroid hormone therapy could reduce a potential cellular immune response after the transfer of zona‐free cloned embryos into the oviduct of recipient female goats. In Experiment 1, seven does were used to study the systemic immunosuppressant effect of the methylprednisolone administration (for 3 days) on blood cell counts. Whole blood was collected prior to treatment with methyprednisolone and then on Days 1, 2, 3, 4, 7, 14, 21 and 28 after the first dose of methylprednisolone for the analysis of haematological parameters. Methylprednisolone treatment significantly reduced circulating white blood cells and neutrophils in comparison with pre‐treatment levels, demonstrating a systemic immunosuppressant effect. In Experiment 2, a group of 58 does were used as recipient females to study the effect of administration of methylprednisolone for 3 days on the establishment of pregnancies after the transfer of zona‐free cloned embryos into the oviducts. No effects on pregnancy rates on Day 30 were observed regarding the distinct treatment groups (control vs. methylprednisolone), the source of oocytes (in vivo‐ vs in vitro‐matured) or the presence or absence of the zona pellucida in embryos. In summary, methylprednisolone was effective at inducing a systemic immunosuppressed state in goats, but the treatment prior to embryo transfer did not affect pregnancy rates. Moreover, pregnancy rates were similar between zona‐free and zona‐intact goat cloned embryos. 相似文献
75.
JB Siqueira E Oba RO Pinho SEF Guimarães TM Neto JD Guimarães 《Reproduction in domestic animals》2014,49(5):851-857
The objective of this work was to verify that mothers classified as super precocious (M1) and precocious (M2) produce more precocious bulls than females classified as normal (M3). This study included 21 186 animals with an average age of 21.29 ± 1.77 months that underwent a breeding soundness evaluation from 1999 to 2008. Of these animals, 2019, 6059 and 13 108 were offspring of M1, M2 and M3 females, respectively. In the breeding soundness examination, the animals were classified as sound for reproduction, sound under a natural mating regime, unsound for reproduction and discarded. To compare the averages obtained for each category of mother within the individual breeding soundness classes, a chi‐square test with a 5% error probability was used, considering the effects of year and month of birth and farm. For the three classes of mothers (M1, M2 and M3), 67.26, 67.22 and 64.16% of bull calves were considered sound for reproduction and 19.71, 19.46 and 21.90% were considered unsound for reproduction, respectively. There was no difference in the frequency of animals that were sound for reproduction under the natural breeding regime between the three classes of mothers (8.87, 9.31 and 9.19%, respectively). There was a difference between the numbers of precocious and normal females that were discarded, with frequencies of 4.01 and 4.75%, respectively (p < 0.05). There were differences in year and month of birth and farm between super precocious and precocious cows in relation to the breeding soundness classification of the animals. It was concluded that the bull offspring of super precocious and precocious cows presented a higher percentage of approval in the breeding soundness examination than the bull offspring of normal cows, demonstrating that the selection for precocity of females has contributed to an increase in the sexual precocity of the herd in relation to the sexual maturity of bulls. 相似文献
76.
When large carnivores cause socioeconomic losses in a community, conflict increases, retaliatory killing of the carnivore can occur, and conservation efforts are undermined. We focused on Participatory Rural Appraisal (PRA) and economic compensation schemes as approaches for managing conflict. PRA is a tool for collecting data on the large carnivore–human conflict and economic compensation schemes for those affected negatively by carnivore presence. We reviewed published papers and reports on large carnivore–human conflicts, PRA, and compensation schemes. This article details insights into common pitfalls, key lessons learned, possible solutions including new approaches for compensation and protocols to be followed while managing large carnivore–human conflict. We hope to contribute to a meaningful dialogue between locals, managers, and researchers and help in effective implementation of conservation programs to mitigate large carnivore–human conflict around the protected areas. 相似文献
77.
A Gonzalez JH Lawton FS Gilbert TM Blackburn I Evans-Freke 《Science (New York, N.Y.)》1998,281(5385):2045-2047
The experimental fragmentation of landscapes of a natural ecosystem resulted in declines in the abundance and distribution of most species in the multispecies animal community inhabiting the landscapes and the extinction of many species. These declines caused the deterioration of the positive interspecific relation between local population abundance and distributional extent in this community. However, when patches were connected by habitat corridors, an immigration "rescue effect" arrested declines in both abundance and distribution and maintained the observed positive relation between them. These results demonstrate the importance of metapopulation dynamics and landscape connectivity for the persistence of populations in fragmented landscapes. 相似文献
78.
79.
Sagar Sharath V. Saini Kuldeep Sharma Anil Kumar Kumar Sachin Kumar Rinesh Fular Ashutosh Shakya Mukesh Upadhaya Deepak Nagar Gaurav C. Shanmuganath Samanta Subhamoy Kumar Suman Ghosh Srikant 《Tropical animal health and production》2020,52(2):611-618
Tropical Animal Health and Production - The isolates of Rhipicephalus microplus collected from Madhya Pradesh (MP), Punjab (PJB) and Uttar Pradesh (UP) states of India were characterized using... 相似文献
80.
Anil Mohapatra T.R. Rautray V. Vijayan Rajeeb K. Mohanty S.K. Dey 《Aquaculture (Amsterdam, Netherlands)》2007,270(1-4):552-558
The trace elemental analysis of two species of mud crab and three species of prawn samples from Chilika lagoon, Orissa, India has been carried out by using Energy Dispersive X-ray Fluorescence (EDXRF) technique available at Institute of Physics, Bhubaneswar. Elements namely K, Ca, Mn, Fe, Cu, Zn, Se, Br, Sr and Pb have been measured in the present investigation. The study indicates the effectiveness of the technique in analyzing biological materials like tissue samples and opens a door for easy analysis of seafood items with a easy, fast, sensitive, simultaneous multi-elemental technique with a simple sample preparation procedure without any chemical treatment. Though all the specimens were collected from the same environment of the lagoon the elemental variation might be due to the differential migration pattern and metabolism or other biological factors. 相似文献