Morphometric analysis of the spinal cord of the Sus scrofa (large white and landrace crossbreed)     

Omowumi Femi-Akinlosotu  Funmilayo Eniola Olopade  Oluwaseun Mustapha  Adejoke Adekanmbi  James O. Olopade 《Anatomia, histologia, embryologia》2023,52(2):289-299

The incidence of spinal cord (SC) injury in developed and undeveloped countries is alarming. The pig (Sus scrofa) has been recommended as a suitable research model for translational studies because of its morphophysiological similarities of organ systems with humans. There is a dearth of information on the SC anatomy of the large white and landrace crossbreed (LW-LC) pigs. We therefore aim to describe the gross morphology and morphometry of its SC. Twelve juvenile LW-LC pigs (six males and six females) were used. The skin and epaxial muscles were dissected to expose the vertebral column. The SC was carefully harvested by laminectomy, and 13 gross SC morphometric parameters were evaluated. Thirty-three spinal nerves were seen emanating from either side of the SC by means of dorsal and ventral spinal roots. The overall average of SC length and weight was 36.23 ± 1.01 cm and 16.60 ± 0.58 g, respectively. However, the mean SC length and weight were higher in females compared with males, with SC weight being statistically significant. A positive relationship between SC length and weight was significant for males (p = 0.0435) but not for females (p = 0.42). Likewise, the strength of the relationship between SC length and weight was significant in males (r = 0.82) but not significant in females (r = 0.41). Baseline data for the morphometric features of the spinal cord in the LW-LC pigs were generated, which will contribute to the knowledge of this species anatomy and useful information on regional anaesthesia that should further strengthen the drive in adopting the pig as a suitable research model for biomedical research.  相似文献   

An evaluation of the Porac River irrigation system     

James A. Weller 《Irrigation and Drainage Systems》1991,5(1):1-17

An irrigation water management research programme was implemented by Hydraulics Research in collaboration with the National Irrigation Administration of the Philippines on the Porac Area of Porac Gumain Rivers Irrigation System. The objectives of the study are to monitor the response of the main canal network to changes in water availability and assess its capability to deliver crop water requirements to sub-areas jointly managed by National Irrigation Administration staff and existing Irrigator Associations. This paper presents an analysis of the response of the main system to the varying irrigation demands, and assesses the conjunctive use of groundwater with surface water and the potential of computer models to assist management with the preparation of the annual irrigation schedules.  相似文献   

Welfare and environmental benefits of integrating commercially viable free-range broiler chickens into newly planted woodland: A UK case study     

Tracey Jones  Ruth Feber  Gabriel Hemery  Paul Cook  Katy James  Curt Lamberth  Marian Dawkins 《Agricultural Systems》2007

The commercial, welfare and environmental impacts of rearing small colonies of free-range chickens in newly planted woodland at two sites in the UK, during the first 2 years of the enterprise, were investigated. Newly planted rather than established trees were used so that commercially viable species could be planted in a way that would suit the management of the chicken enterprise, and small colonies were used so that farmers wishing to diversify could buy into the system progressively. It was anticipated that marketing a high specification product would provide an immediate income, whilst waiting for the future investment in trees to grow.  相似文献   

Controlled water table management as a strategy for reducing salt loads from subsurface drainage under perennial agriculture in semi-arid Australia   总被引：2，自引：0，他引：2  

John?W.?HornbuckleEmail author  Evan?W.?Christen  James?E.?Ayars  Richard?D.?Faulkner 《Irrigation and Drainage Systems》2005,19(2):145-159

Recent community based actions to ensure the sustainability of irrigation and protection of associated ecosystems in the Murrumbidgee Irrigation Area (MIA) of Australia has seen the implementation of a regional Land and Water Management Plan. This aims to improve land and water management within the irrigation area and minimise downstream impacts associated with irrigation. One of the plan objectives is to decrease current salt loads generated from subsurface drainage in perennial horticulture within the area from 20 000 tonnes/year to 17 000 tonnes/year. In order to meet such objectives Controlled Water table Management (CWM) is being investigated as a possible ‘Best Management Practice’, to reduce drainage volumes and salt loads.During 2000–2002 a trial was conducted on a 15 ha subsurface drained vineyard. This compared a traditional unmanaged subsurface drainage system with a controlled drainage system utilizing weirs to maintain water tables and changes in irrigation scheduling to maximize the potential crop use of a shallow water table. Drainage volumes, salt loads and water table elevations throughout the field were monitored to investigate the effects of controlled drainage on drain flows and salt loads.Results from the experiment showed that controlled drainage significantly reduced drainage volumes and salt loads compared to unmanaged systems. However, there were marked increases in soil salinity which will need to be carefully monitored and managed.  相似文献   

Simulation of the soil-water dynamics and corn yields under deficit irrigation   总被引：2，自引：0，他引：2  

Jan Dierckx  James R. Gilley  Jan Feyen  Chris Belmans 《Irrigation Science》1988,9(2):105-125

Summary A simulation model capable of predicting the yield response of corn to a limited water supply was developed by combining two existing mathematical models. The resulting computer model was evaluated using experimental data taken under a wide range of soil moisture conditions. The soil profile water balances was simulated using SWATRE and SUCROS was used to model the crop growth in response to environmental conditions. In addition to the integration of the two existing models, some minor changes were made to each in an effort to improve the accuracy of the combined models. The model input parameters were derived entirely from published literature. The experimental data necessary for model validation were available from irrigation studies at the Sandhills Agricultural Laboratory of the University of Nebraska. These experiments not only provided the required input soil and climatic data, but also the observed irrigation levels, soil moisture distributions and crop yield required for model validation. Initial evaluation of the computer model indicates that the combined model adequately describes crop evapotranspiration, soil moisture extraction and crop yield under a fairly wide range of soil moisture stress. Additional modifications for the prediction of leaf area expansion and senescence, especially under moisture stress, are needed to improve the accuracy of the model.  相似文献   

Visits to the U.S. Bureau of Reclamation from South Asia and the Middle East, 1946–1990: An indicator of changing international programs and politics     

James L. Wescoat Jr.  Roger Smith  David Schaad 《Irrigation and Drainage Systems》1992,6(1):55-67

International study programs have contributed to the diffusion of modern irrigation technologies, approaches, and problems. But the patterns and processes of international travel have received little attention to date. This paper examines foreign visits to the US Bureau of Reclamation (USBR) from South Asia and the Middle East from 1946 to 1990. Using data from the Foreign Activities Branch of the USBR, we compare the participation rates from 16 countries in South Asia and the Middle East. India, Turkey, and Egypt had the highest rates of participation, followed by Pakistan, Iran, and Israel. The frequency of visits is influenced by political, economic, cultural, and institutional factors. But the most important factors appear to be foreign relations and geopolitics. Given the problems faced by national irrigation bureaucracies around the world, there is a need to focus more directly on political factors than in the past.  相似文献   

Histological and immunohistochemical features of cutaneous mast cell tumor in six captive four-toed hedgehogs (Atelerix albiventris)     

Nguyen Vu SON  James Kenn CHAMBERS  Makoto NAKATA  Yasutsugu MIWA  Hiroyuki NAKAYAMA  Kazuyuki UCHIDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(2):208

This report described the histopathological and immunohistochemical features of cutaneous mast cell tumor (MCT) in six hedgehogs. The hedgehogs presented single cutaneous mass with ulcer and crusting. Histologically, the neoplastic lesions were characterized by the proliferation of well-differentiated mast cells (3 cases), and atypical mast cells (3 cases) with one atypical histiocytic morphology. Immunohistochemically, tumor cells were positive for KIT and mast cell tryptase, and were negative for Iba-1. In well-differentiated MCT, all patients were clinically improved and survived more than 365 days after surgical excision, whereas an atypical histiocytic MCT showed aggressive behavior with re-recurrence, and the animal died 115 days after surgery. These findings suggest that, compatible with other animals, well-differentiated MCT has a better prognosis in hedgehogs.  相似文献   

Host Plant-Based Artificial Diets Enhance Development,Survival and Fecundity of the Edible Long-Horned Grasshopper Ruspolia differens (Orthoptera: Tettigoniidae)     

Alfonce Leonard  James P Egonyu  Chrysantus M Tanga  Samuel Kyamanywa  Sunday Ekesi  Fathiya M Khamis  Sevgan Subramanian 《Journal of insect science (Online)》2022,22(2)

Wild swarms of the long-horned grasshoppers Ruspolia differens (Serville) which are widely harvested for consumption and sale in Africa are seasonal and unsustainable, hence the need for innovative ways of artificially producing the insects. We investigated the development, survival, and reproduction of R. differens in the laboratory on diets mixed with host plants [Digitaria gayana Kunth, Cynodon dactylon (L.) and Megathyrsus maximus Jacq (Poales: Poaceae); Ageratum conyzoides L. (Asterales: Asteraceae)] identified from guts of their wild conspecifics with a view to developing a suitable diet for artificial mass rearing of the edible insect. A standard diet comprising ground black soldier fly, Hermetia illucens L. (Diptera: Startiomyidae) larvae, soybean flour, maize flour, vitamin premix, and ground bones was tested for rearing R. differens as a control against the same ingredients incorporated with individual powders of the different host plants. Whereas R. differens developed more slowly in the diet mixed with D. gayana than in the control diet; its development was faster in the diet mixed with C. dactylon. Mortalities of R. differens in host plant-based diets were 42.5–52.5%, far lower than in the control diet with 71% mortality. The insects raised on the diet mixed with M. maximus laid approximately twice more eggs compared to R. differens fecundities from the rest of the diets. However, inclusion of host plants in the diets had no detectable influence on R. differens adult weight and longevity. These findings support inclusion of specific host plants in artificial diets used for mass rearing of R. differens to enhance its survival, development, and fecundity.  相似文献   

Insular pest control within a metapopulation context     

James C. Russell  Jamie W.B. Mackay  Jawad Abdelkrim 《Biological conservation》2009,142(7):1404-1410

Introduced pests threaten many species and their control is generally beneficial for conservation, particularly on islands where complete eradication is possible. Unfortunately on ‘nearshore’ islands neighbouring source populations exist and unaided reinvasion is likely. Pest control programmes at these sites thus require a metapopulation context to adequately manage movements between source and sink populations. We investigated the ecology of introduced ship rats (Rattus rattus) on a nearshore island, and gene flow with adjacent mainland populations, in order to understand the metapopulation dynamics and relative levels of pest control required within the landscape. We sampled the entire population by trapping (n = 30), achieving eradication, and found a low rat density (3.2 ha⁻¹) indicative of a sink population. Seed and other plant material constituted the major dietary component of rats. Despite its proximity to mainland source populations, the island population was genetically distinct with reduced allelic diversity caused by a recent reinvasion founder effect. Genetic analyses also detected recent migrants between the populations. In contrast, two mainland populations separated by a similar distance displayed complete genetic mixing. The small water gap therefore provides a sufficient barrier to lower the migration rate to the island and delay reinvasion, which nonetheless eventually happens. In order to maintain nearshore islands pest-free, conservation management will require a metapopulation approach simultaneously focusing on both island and source population pest control.  相似文献   

Soil nitrogen availability alters rhizodeposition carbon flux into the soil microbial community     

Yaying Li  Juan Wang  Fuxiao Pan  Stephen James Chapman  Huaiying Yao 《Journal of Soils and Sediments》2016,16(5):1472-1480

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