Passive immunization with antiserum to adrenocorticotropin increases weight gain in normal female rats.     

M N Sillence  M R Jones  P Lowry  J R Bassett 《Journal of animal science》1992,70(5):1382-1388

Passive immunization against ACTH was used to test the hypothesis that growth in female rats is constrained by physiological concentrations of glucocorticoids. When animals were stressed by 15-min exposure to ether before blood sampling by cardiac puncture, serum concentrations of corticosterone were lower (P less than .05) in immunized rats than in stressed controls. The maximum effect was apparent 2 h after injection of ACTH antiserum, and no effect was apparent 6 h after injection. To examine the effects of ACTH immunization on growth, rats received daily injections of either saline, sheep immunoglobulin G, or ACTH antiserum, 2 h before the afternoon peak in plasma concentrations of corticosterone. After 7 d of treatment, rats treated with ACTH antiserum had gained 37% more body weight than saline-injected controls, and this effect was accompanied by a 59% reduction in peak plasma concentrations of corticosterone. Immunoglobulin G purified from normal sheep serum had no effect on weight gain. It is concluded that growth rate in normal female rats can be stimulated through the suppression of adrenal activity.  相似文献   

SONOGRAPHIC EVALUATION OF URINARY BLADDER WALL THICKNESS IN NORMAL DOGS     

Amy L.  Geisse  DVM  Jennifer E.  Lowry  DVM  MS  David J.  Schaeffer  PHD  Charles W.  Smith  DVM  MS 《Veterinary radiology & ultrasound》1997,38(2):132-137

Urinary bladder wall thickness was evaluated by ultrasonography in 16 normal dogs. Sterile saline solution was administered via urinary catheters to control the degree of bladder distention. Bladder wall thickness was measured on static ultrasound images in 4 locations and at 3 degrees of bladder distention (minimal, mild, and moderate). Four randomized distention sequences with 3 distentions per sequence were performed on each dog and the data were analyzed using Williams' balanced Latin square. Mean bladder wall thickness was 2.3 mm in minimally distended bladders (0.5 ml/kg saline), 1.6 mm in mildly distended bladders (2 ml/kg saline) and 1.4 mm in moderately distended bladders (4 ml/kg saline). Mean bladder wall thickness increased significantly with increasing body weight and with decreasing bladder distention. The caudoventral measurement location produced a statistically significant smaller measurement, with a difference of 0.3 mm. Sex did not affect bladder wall thickness. Distention sequence and repetition of distentions did not affect bladder wall thickness.  相似文献   

Clinical and Immunohistochemical Characterization of Thymic Lymphosarcoma in a Heifer   总被引：1，自引：0，他引：1  

Andrew N. Alexander  Peter D. Constable  William A. Meier  Richard A. French  Dawn E. Morin  Jennifer E. Lowry  Walter E. Hoffman 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1996,10(4):275-278

A 2–year-old Holstein heifer with a swollen brisket, jugular vein distention, muffled heart sounds, tachycardia, and free gas bloat was examined. Thymic lymphosarcoma was suspected based on a negative agar gel immunodiffusion test for bovine leukemia virus, presence of atypical lymphocytes in pleural fluid, and detection of a mass in the thoracic inlet. Right-sided cardiac catheterization was performed, and markedly increased jugular venous pressures (41 mm Hg) with a pressure gradient of 29 mm Hg immediately cranial to the heart indicated constriction of the cranial vena cava. Immunohistochemical staining of formalin fixed, paraffin-embedded tissue sections of the tumor using a rabbit anti-human T cell, CD3 polyclonal antibody confirmed that the neoplastic lymphocytes were of thymic origin. J Vet Intern Med 1996;275–278. Copyright © 1996 by the American College of Veterinary Internal Medicine .  相似文献   

Social dominance difference,given limited access to common food,between hens selected and unselected for increased egg production     

Dorothy C. Lowry  H. Abplanalp 《British poultry science》1972,13(4):365-376

White Leghorn hens, belonging to a population (P) selected on an index for high egg number combined with slightly increased egg size, were compared for social dominance with a control line (R) derived from P in 1958 and reproduced independently over ten generations of random selection. The P line matured 12 d earlier, laid 18 more eggs in the part year to 1st January, had an increased egg production from 1st January to 1st October in the second year, laid heavier (2 g) eggs and had slightly longer shanks than the R line. Body size of the two lines, however, was similar.

Observations on the social dominance of hens were made in pens containing four hungry P‐ and four hungry R‐hens when they were 70 or more weeks of age. Observations focused on the hens’ ability to take and maintain a place at a food trough allowing only limited access. Larger scores, corresponding to high ranks, were given to the hens which were able to spend the most time eating.

Clear‐cut differences of social rank in favour of the selected production line were found in all 20 pens. Phenotypic correlations between production characteristics of individual R‐hens and their social rank scores were in agreement with other studies, showing that within genetic lines hens of high social status matured earlier and had larger body size than the more timid individuals.  相似文献   

Effect of dietary calcium on selenium retention in postweaning swine     

K R Lowry  D C Mahan  J R Corley 《Journal of animal science》1985,60(6):1429-1437

Two experiments were conducted to evaluate the effect of dietary Se and Ca on Se utilization in postweaning swine. Two levels of dietary Se (.3 or 5.0 ppm) supplemented as sodium selenite and four levels of total dietary Ca (.50, .80, 1.10 or 1.40%) in a 20% protein, corn-soybean meal diet were evaluated. Inorganic Ca was supplied from dicalcium phosphate and limestone. In Exp. I, 135 pigs weaned at 4 wk of age were allotted by sex, litter and weight and fed a basal diet for 7 d and then their treatment diets for a 28-d period. Plasma and tissue were collected at the end of the trial for Se concentration and glutathione peroxidase (GSH-Px) activity. Dietary Ca had no effect on gain or feed measurements but 5.0 ppm Se depressed daily gain slightly. When 5.0 ppm dietary Se was fed, there resulted higher liver, kidney, heart and longissimus muscle Se concentrations than when .3 ppm was provided, but dietary Ca had no effect on tissue Se values within each dietary Se level. Plasma GSH-Px increased when higher dietary Se was provided, whereas neither heart nor liver GSH-Px activity was affected by dietary Se or Ca level. In Exp. II, a 5-d balance trial was conducted with 32 barrows after adjustment to their treatment diet for a 28-d period. Selenium retention increased quadratically as dietary Ca increased, whereas Ca retention was not affected by dietary Se. These results suggest that low dietary Ca levels may reduce total Se retention but not Se metabolism within body tissue.  相似文献   

Reducing the mortality of freshwater turtles in commercial fish traps     

M. B. Lowry  B. C. Pease  K. Graham  T. R. Walford 《水产资源保护:海洋与淡水生态系统》2005,15(1):7-21

• 1. Mortality of air‐breathing vertebrates has been recognized for some time as a significant risk in Australian inland fisheries. There has often been conflict between the desires of fishers to maximize catches of their target species and the implementation of effective methods to reduce nontarget bycatch.
• 2. Two trials were conducted to evaluate the effectiveness of modifications to fish traps designed to prevent the capture of freshwater turtles (Emydura macquarii) and to facilitate their release. The first study evaluated the use of 100 mm exclusion rings to prevent turtles entering eel traps. The second study assessed two configurations of a carp trap designed to release the accidental catch of turtles.
• 3. Eel traps fitted with 100 mm exclusion rings significantly reduced the turtle bycatch, with no significant difference being observed between mean size of eels captured in traps fitted with exclusion rings and traps without rings.
• 4. The trials on the modified carp trap confirmed that they effectively retained carp and released a majority (77%) of turtles over a 4 h period. Turtles retained in the carp traps were significantly longer than those that found their way out of the trap.
• 5. This study demonstrates the different approaches that can be taken to achieve a reduction in non‐target bycatch associated with traps, and illustrates the importance of exploiting both the physical and behavioural differences of the target and non‐target species in order to develop appropriate gear designs that effectively restrict the entry, or facilitate the release, of bycatch species.

Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

Effects of sea-level rise and storm-enhanced flooding on Pacific harbour seal habitat: A comparison of haul-out changes at the Russian and Eel river estuaries     

Karen Backe  Ellen Hines  Karina J. Nielsen  Doug George  Elinor Twohy  Mark Lowry 《水产资源保护:海洋与淡水生态系统》2021,31(7):1749-1759

1. Patterns and changes in the distribution of coastal marine mammals can serve as indicators of environmental change that fill critical information gaps in coastal and marine environments. Coastal habitats are particularly vulnerable to the effects of near-term sea-level rise.
2. In California, Pacific harbour seals (Phoca vitulina richardii) are a natural indicator species of coastal change because of their reliance on terrestrial habitats, abundance, distribution, and site fidelity. Pacific harbour seals are marine top predators that are easily observed while hauled out at terrestrial sites, which are essential for resting, pupping, and moulting.
3. Although increasing inundation from recent sea-level rise and storm-driven flooding has changed the Californian coastline, little is known about the effect of future sea-level rise and increased storm frequency and strength on harbour seal haulout site availability and quality in California.
4. Harbour seal habitat was modelled at two sandbar-built estuaries under a series of likely sea-level rise and storm scenarios. The model outputs suggest that, over time, habitat at both estuaries decreased with increasing sea level, and storm-enhanced water levels contributed significantly to habitat flooding. These changes reflect pressures on coastal habitats that have an impact on human and natural systems.

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Land suitability evaluation for multiple crop agroforestry planning using GIS and multi-criteria decision analysis: A case study in Fiji     

Wotlolan  Dean L.  Lowry  John H.  Wales  Nathan A.  Glencross  Kevin 《Agroforestry Systems》2021,95(8):1519-1532

We present novel methods that use geographic information systems (GIS) and multi-criteria decision analysis (MCDA) to evaluate land suitability for a set of seven agroforestry crops, with the aim to differentiate relative land suitability and its potential to achieve different benefit goals for the Sigatoka Valley, Fiji. Our first model (Land Suitability) identifies optimal areas for each crop based on readily available edaphic and environmental cultivation criteria and common GIS datasets. The second model (Weighted Maximum) uses objective approaches for weighting the relative importance of target crops to derive a multi-crop suitability map. We use the analytical hierarchy process (AHP) technique (a form of MCDA) to identify the relative importance of five benefit types (i.e. agroforestry initiative goals/AHP Objectives). AHP criterion weights were used to map the most important crops for different agroforestry goals. Our methods are unique among GIS-MCDA applications of land suitability analysis in that our aim was to investigate and spatially evaluate land use suitability for multiple crops on a per-crop basis, whereas the aim of most GIS-MCDA land suitability analyses is to evaluate relative suitability (e.g. low, medium, high), evaluate potential for different land uses (e.g. production, intensive, or multifunctional) or land suitability for a single crop. We conclude that the methods described can be adapted to agroforestry initiatives and other similar land use suitability applications in the Pacific region and other geographical settings.

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Spin rate of asteroid (54509) 2000 PH5 increasing due to the YORP effect     

Taylor PA  Margot JL  Vokrouhlicky D  Scheeres DJ  Pravec P  Lowry SC  Fitzsimmons A  Nolan MC  Ostro SJ  Benner LA  Giorgini JD  Magri C 《Science (New York, N.Y.)》2007,316(5822):274-277

Radar and optical observations reveal that the continuous increase in the spin rate of near-Earth asteroid (54509) 2000 PH5 can be attributed to the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect, a torque due to sunlight. The change in spin rate is in reasonable agreement with theoretical predictions for the YORP acceleration of a body with the radar-determined size, shape, and spin state of 2000 PH5. The detection of asteroid spin-up supports the YORP effect as an explanation for the anomalous distribution of spin rates for asteroids under 10 kilometers in diameter and as a binary formation mechanism.  相似文献