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The design, construction and use of a device to detect changes in deer pedicle volume are described. The device is highly sensitive for detecting the initiation of pedicle growth. Between-sample differences of 170 mm3 in the pedicle volume of live deer were detected (triplicate measurements) using the detector; these correspond to a change in height of the pedicle of at most 0.67 mm. The within sample coefficient of variation was 1.4%. The pedicle growth detector enables more precise measurements to be obtained for identifying the onset of pedicle development to the nearest week than is currently possible with palpation.  相似文献   
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Heart rate and behaviour during and following velvet antler removal were monitored in yearling red deer stags to determine the extent to which this procedure was perceived by the deer to be aversive. Nine stags normally kept at pasture were habituated over 5 weeks to the following daily handling procedure. Each deer was fitted with a harness containing a heart rate monitor. It was then allowed to run through a fixed course in a deer yard, restrained for 40 s in a mechanical deer crush, and then confined for 3.5 h with the remainder of the group of stags in an indoor pen containing food and water. In Week 6, the deer were subjected to either restraint for 6 minutes (the control treatment) or removal of one velvet antler under local anaesthesia. Each velvet antler was removed on separate occasions, either on Days 1 and 2 (five deer) or Days 3 and 4 (four deer). The control treatment was applied to all deer when velvet antler was not being removed, and on Day 5. Heart rate and behaviour (time taken to enter the treatment area, and number of struggles made during restraint) were measured before and during treatment, and post-treatment activities were recorded at 0, 1 and 3 h (indoors), and at 6 and 9 h (at pasture). Heart rate was higher during the second velvet antler removal treatment than during the first, but lower during the second control treatment than the first (P<0.05). During velvet antler removal, stags struggled more, and after the treatment flicked their ears, shook their heads, and groomed themselves more than control stags (P<0.05). Stags whose velvet antler had been removed spent less time eating than control stags, and spent progressively more time sitting during the 3.5 h of confinement (P<0.05). However, during the paddock observation at 9 h post-treatment, stags which had had their velvet antler removed grazed more than control stags (P<0.05). The increase in heart rate over the two velvet antler removal treatments and the greater amount of struggling during velvet antler removal indicated that it was more aversive than the control treatment. Post-treatment differences in behaviour may have been due to pain following velvet antler removal.  相似文献   
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Since its inception, in 1885 the Buckeye Irrigation Canal has delivered irrigation water in the Buckeye Valley, southwest of Phoenix, Arizona. Throughout its tenure the owners of the canal have consulted design professionals for its engineering needs. Early engineering in 1885 established canal alignments, delivery points and channel capacity. Until recently, the Buckeye Valley was a rural area relying on agricultural revenues to drive the local economy. Now, due to the recent housing market boom new homes started springing up like corn in September driving the existing open-channel laterals below grade into a patch work redesigned pipeline system. Because of these changes, professional construction managers are an enormous benefit to the Buckeye Water Conservation and Drainage District (BWCDD), the owner of the canal.As a result of this urbanization, contractors working for home developers are installing irrigation pipelines and systems with the focus of completing the project as quickly and economically as possible. Irrigation providers, on the other hand, focus on meeting the agricultural needs of their clients with consistent and uninterrupted water delivery. The services of a professional construction manager help both entities achieve their respective goals, shield BWCDD from construction of sub-par systems and risk, maintain uninterrupted service to growers and providing the technical expertise to communicate with both BWCDD and contractors.Construction managers provide a number of services to rural irrigation districts under-going urbanization. They team with an irrigation district by:
  • Understanding irrigation design concepts;
  • Understanding agricultural demands;
  • Providing a thorough knowledge of construction practices and standards;
  • Creating long-term design functionality;
  • Reducing stress on and increasing productivity of personnel;
  • Coordinating construction activities with water deliveries;
  • Verifying constructed facilities perform as designed, which reduces maintenance costs.
Construction managers represent an irrigation district in the field by:
  • Reviewing development plans for adherence to current construction standards and practices and coordinates construction schedules with water delivery needs;
  • Observing construction for proper installation;
  • Clarifying installers understanding of plans and specifications;
  • Coordinating interruptions in service;
  • Tracking multiple construction projects;
  • Explaining agricultural practices to contractor personnel;
  • Providing a single point of contact for construction related correspondence.
These “boots on the ground” create a local presence with a focus on the specific needs unique to an irrigation district. They provide a liaison while minimizing the impact to its growers.This paper will discuss the strain of urbanization on an irrigation district and the benefits of an engineering consulting firm to manage construction projects. The benefits include expertise, technical resources, design capability, coordination and inspection. Construction managers can help protect an irrigation district from being overwhelmed by rapid urbanization.  相似文献   
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A 19-yr-old binturong (Arctictis binturong) with acute upper respiratory disease was euthanized. Postmortem findings included hepatocellular carcinoma, pancreatic islet cell carcinoma, and renal adenocarcinoma with metastasis to the spleen, pleura, and pericardium. A link between primary hepatic and renal neoplasms has been noted in older humans.  相似文献   
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Henneguya pilosa sp. n., a new species of myxosporean from the gill filaments of the white piranha, Serrasalmus altuvei Ramirez, 1965 (Characidae), a freshwater teleost fish collected in the Zoological Garden of the city of Teresina (Piauí), Brazil, is described from light and transmission electron microscope observations. This myxosporean produced small plasmodia (up to 0.2 mm in diameter), each one containing all life-cycle stages of the parasite, including numerous spores. The spores, laterally compressed, averaged 54.2 (52.3-56.0) microm in total length and consisted of two unequal valves adhering together along the suture line and two caudal processes. The spore body measured 21.1 (20.0-23.1) microm in length, 5.9 (5.5-6.3) microm in width, and 2.2 (1.9-2.6) microm in thickness. The two equal ellipsoidal polar capsules of 7.4 (7.1-7.6) microm long and 1.2 (1.0-1.3) microm wide possessed a polar filament with 11-12 (rarely 13) turns. All surfaces of the spores were covered with a tightly adherent complex network of numerous densely ramified granulo-fibrillar masses, the longest measuring 1.5 microm long, observed around the caudal processes. The prevalence of infection was 30%. The taxonomic affinities of this parasite with other of the same genus in freshwater South American fish species are discussed.  相似文献   
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OBJECTIVE: To investigate cryopreservation-induced capacitation-like changes in equine spermatozoa frozen in three different media using chlortetracycline (CTC) fluorescence staining analysis. PROCEDURE: Semen collected from three stallions was diluted in one of three centrifugation media and, after centrifugation and removal of supernatant, extended in corresponding freezing media containing additional egg yolk, glycerol, lactose and Equex paste. The semen was frozen in 5 mL straws and the spermatozoa assessed for motility and membrane quality after thawing. RESULTS: Following centrifugation, spermatozoa diluted with modified Kenney's Centrifugation Medium (MKCM) displayed a higher percentage of (normal) F pattern (94.3%) compared with spermatozoa in Kenney's Centrifugation Medium (KCM) (84.9%) and Glucose-EDTA Centrifugation Medium (GECM) (85.2%). Conversely, the percentage of spermatozoa displaying the (capacitated) B pattern was higher in the KCM (14.1%) and GECM (13.8%) than in the MKCM (5.0%). Following freezing-thawing, there were lower percentages of spermatozoa displaying the AR (acrosome reacted) pattern in modified Kenney's Freezing Medium (MKFM) (45.6%) compared with Kenney's Freezing Medium (KFM) (61.4%) and lactose-EDTA Freezing Medium (LEFM) (61.1%). There was a correspondingly higher percentage of spermatozoa displaying the B pattern in MKFM (52.3%) compared with KFM (37.9%) and LEFM (38.6%). There was no significant difference between the freezing media in the percentage of spermatozoa displaying the F pattern. The percentage of progressively motile spermatozoa was also influenced by the type of freezing medium (P < 0.001). Post-thaw percentages of progressively motile spermatozoa, frozen in MKFM, KFM, and LEFM, were 31.4, 25.8 and 23.3%, respectively. CONCLUSION: MKFM was the preferred medium for cryopreservation of equine spermatozoa due to its superior protection against changes in motility and membrane quality compared with the other freezing media studied.  相似文献   
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