Serum neutralization of cytotoxin from Pasteurella haemolytica, serotype 1 and resistance to experimental bovine pneumonic pasteurellosis   总被引：13，自引：0，他引：13  

M J Gentry  A W Confer  R J Panciera 《Veterinary immunology and immunopathology》1985,9(3):239-250

Sera from several groups of experimental calves were tested for cytotoxin neutralizing capacity. The relationship between this capability and resistance of the animals to an experimental challenge was examined. All undiluted bovine sera tested, other than fetal bovine serum, neutralized cytotoxin. Preadsorption of selected sera with formalin-killed P. haemolytica did not reduce their neutralizing capacity. Crude IgG fractions extracted from bovine sera retained neutralizing capacity as well. Cytotoxin neutralization titers were determined by serial dilution of sera from cattle which were previously unexposed, naturally exposed, or exposed by vaccination to the organism. Both live and killed vaccines were used. Prior exposure to live organisms resulted in the production of antibodies to both cell surface antigens and cytotoxin, whereas exposure to the killed vaccine resulted in the production of antibodies primarily to cell surface antigens. Resistance to experimental challenge with the organism correlated directly with serum cytotoxin neutralizing titers.  相似文献   

Versatility of the Angularis Oris Axial Pattern Flap for Facial Reconstruction          下载免费PDF全文

Sara L. Losinski  Bryden J. Stanley  Sandra P. Schallberger  Laura L. Nelson  Heather A.M. Towle Millard 《Veterinary surgery : VS》2015,44(8):930-938

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Adaptation and evaluation of the National Cancer Institute's Diet History Questionnaire and nutrient database for Canadian populations     

Csizmadi I  Kahle L  Ullman R  Dawe U  Zimmerman TP  Friedenreich CM  Bryant H  Subar AF 《Public health nutrition》2007,10(1):88-96

BACKGROUND AND OBJECTIVE: Despite assumed similarities in Canadian and US dietary habits, some differences in food availability and nutrient fortification exist. Food-frequency questionnaires designed for the USA may therefore not provide the most accurate estimates of dietary intake in Canadian populations. Hence, we undertook to evaluate and modify the National Cancer Institute's Diet History Questionnaire (DHQ) and nutrient database. METHODS: Of the foods queried on the DHQ, those most likely to differ in nutrient composition were identified. Where possible these foods were matched to comparable foods in the Canadian Nutrient File. Nutrient values were examined and modified to reflect the Canadian content of minerals (calcium, iron, zinc) and vitamins (A, C, D, thiamin, riboflavin, niacin, B6, folate and B12). DHQs completed by 13 181 Alberta Cohort Study participants aged 35-69 years were analysed to estimate nutrient intakes using the original US and modified versions of the DHQ databases. Misclassification of intake for meeting the Dietary Reference Intake (DRI) was determined following analysis with the US nutrient database. RESULTS: Twenty-five per cent of 2411 foods deemed most likely to differ in nutrient profile were subsequently modified for folate, 11% for vitamin D, 10% for calcium and riboflavin, and between 7 and 10% for the remaining nutrients of interest. Misclassification with respect to meeting the DRI varied but was highest for folate (7%) and vitamin A (7%) among men, and for vitamin D (7%) among women over 50 years of age. CONCLUSIOn: Errors in nutrient intake estimates owing to differences in food fortification between the USA and Canada can be reduced in Canadian populations by using nutrient databases that reflect Canadian fortification practices.  相似文献   

COMPARISON BETWEEN COMPUTED TOMOGRAPHY,FLUOROSCOPY, AND ULTRASONOGRAPHY FOR GUIDING PERCUTANEOUS INJECTION OF THE CANINE INTERVERTEBRAL DISC     

Shawn D. MacKenzie  Jeff L. Caswell  Brigitte A. Brisson  Luis Gaitero  Heather J. Chalmers 《Veterinary radiology & ultrasound》2014,55(5):571-581

A minimally invasive method for delivering injectable therapeutic agents would be desirable for the treatment of intervertebral disc disease in dogs. The purpose of this study was to compare computed tomography (CT), ultrasonography (US), and fluoroscopy modalities for guiding percutaneous injection into canine intervertebral discs. Intervertebral discs of 14 dog cadavers were injected with a gelified ethanol therapeutic agent. Successful injectate placement and injectate leakage were determined based on necropsy inspection of discs. Injection into the nucleus pulposus was successful in 55 of 78 (71%) of all injected discs. Injections guided using CT and fluoroscopy were significantly more successful than US‐guided injections. Odds of successful injection without leakage were greater for CT vs. US (P = 0.0026) but there was no significant difference between CT and fluoroscopy (P = 0.0620). Injection success rates did not differ among vertebral sites or dog cadavers of varying weights. Forty‐nine (63%) of injection sites had injectate leakage outside the disc and 10 of these involved structures within the vertebral canal. The highest rate of injection success with the least amount of leakage was achieved with CT guidance. Findings indicated that CT, fluoroscopy, and US are feasible modalities for guiding percutaneous injection of a gelified ethanol therapeutic agent into the canine intervertebral disc, with moderate to high success rates for different regions of the spine. However, a moderately high rate of injectate leakage occurred outside of the disc and this should be taken into consideration for future safety and efficacy studies.  相似文献   

Heat stress: A major contributor to poor animal welfare associated with long-haul live export voyages     

Malcolm P. Caulfield  Heather Cambridge  Susan F. Foster  Paul D. McGreevy 《Veterinary journal (London, England : 1997)》2014,199(2):223-228

Recent investigations by the Australian Department of Agriculture, Fisheries and Forestry into high mortalities on live export voyages from Australia to the Middle East during the Northern hemisphere summer suggest that animal welfare may be compromised by heat stress. The live export industry has generated a computer model that aims to assess the risk of heat stress and to contain mortality levels on live export ships below certain arbitrary limits. Although the model must be complied with under Australian law, it is not currently available for independent scientific scrutiny, and there is concern that model and the mandated space allowances are inadequate. This review appraises the relevant literature on heat stress in sheep and cattle, including laboratory studies aimed at mimicking the ambient temperatures and humidity levels likely to be encountered on live export voyages. Animal welfare is likely to be very poor as a result of heat stress in some shipments.  相似文献   

Aloe vera: an in vitro study of effects on corneal wound closure and collagenase activity     

Elizabeth M. Curto  Amber Labelle  Heather L. Chandler 《Veterinary ophthalmology》2014,17(6):403-410

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A weight‐of‐evidence approach for defining thermal sensitivity in a federally endangered species     

Heather S. Galbraith  Carrie J. Blakeslee  Daniel E. Spooner  William A. Lellis 《水产资源保护:海洋与淡水生态系统》2020,30(3):540-553

1. Managing for threatened and endangered species under changing environmental conditions is a challenge faced by resource managers worldwide. Lack of basic knowledge of the biology and habitat requirements of these species can contribute to this difficulty but is exacerbated by the limitations of working with rare species (i.e. few individuals) or unrefined and non‐lethal methods for evaluating stress.
2. A weight‐of‐evidence approach was used to evaluate the thermal biology of the federally endangered dwarf wedgemussel (Alasmidonta heterodon), using cumulative results from multiple experimental assessments, co‐occurring species, and their host fish to begin defining the thermal limits and optimal conditions for the species.
3. Results suggest that dwarf wedgemussel and its host fish are thermally sensitive species compared with other Atlantic‐slope mussels, with a lower critical thermal maximum (CTM) and the selection of reduced temperatures during choice experiments.
4. Physiological studies resulted in a lack of statistical significance, primarily owing to low power, which was a function of sample size – an unavoidable problem when studying rare species. Given these limitations, thermal choice and CTM may be more useful end points than physiological processes such as clearance and respiration rates when dealing with sample‐size limitations.
5. These results suggest that management strategies that avoid exposing dwarf wedgemussel and its thermally sensitive host fish to extreme temperatures could be important for species conservation.

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Conservation status of the world's hagfish species and the loss of phylogenetic diversity and ecosystem function     

Landon Knapp  Michael M. Mincarone  Heather Harwell  Beth Polidoro  Jonnell Sanciangco  Kent Carpenter 《水产资源保护:海洋与淡水生态系统》2011,21(5):401-411

Effects of modulatory agents on neurally-mediated responses of trout intestinal smooth musclein vitro     

Dr. John F. Burka  Heather A. Briand  Cheryl Ann Wartman  Jeffrey G. Hogan  William P. Ireland 《Fish physiology and biochemistry》1996,15(2):95-104

Mediators and mechanisms responsible for the inhibitory modulation of trout intestinal smooth muscle were examined using a series of putative mediators and substances known to modulate neurotransmission in mammalian systems. Frequency response relationships to transmural stimulation and concentration response relationships to 5-hydroxytryptamine, carbachol, and substance P were established on paired segments of rainbow trout intestinein vitro in the presence and absence of putative modulatory agents. Modulation of neurally-mediated contractions of trout intestine was achieved with dibutyryl cyclic AMP and forskolin, agents that increase intracellular levels of cyclic AMP. The effect appears to be at the level of the smooth muscle, since the adenylate cyclase activator, forskolin, inhibited muscarinic and serotoninergic contractions as well as transmurally stimulated contractions. Substance P-induced contractions were unaffected by forskolin. The endogenous agonists/neurotransmitters which would increase cyclic AMP levels in rainbow trout intestinal smooth muscle are as yet unknown. The effects do not appear to be modulated by vasoactive intestinal peptide (VIP), calcitonin, calcitonin gene-related peptide (CGRP), or agents that activate -adrenoceptors. Prostaglandin E₂ (PGE₂) and ₂-adrenergenic agonists are possible agents which will decrease contractility of the smooth muscle. They were only active in the proximal intestine and on transmurally stimulated contractions. The effects of both PGE₂ and ₂-agonists appear to be prejunctional, decreasing release of contractile neurotransmitters in the enteric nervous system.  相似文献   

Effect of vaccination with live or killed Pasteurella haemolytica on resistance to experimental bovine pneumonic pasteurellosis   总被引：13，自引：0，他引：13  

A W Confer  R J Panciera  R W Fulton  M J Gentry  J A Rummage 《American journal of veterinary research》1985,46(2):342-347

Using 6- to 8-month-old beef calves, 3 experiments were conducted to compare the effect of vaccination with live or killed Pasteurella haemolytica on resistance to a transthoracic challenge exposure with the organism and to correlate serum antibody response with resistance. In each experiment, calves were vaccinated twice at 1-week intervals and were challenge exposed 21 days after the first inoculation. Lung lesions were evaluated by a system, such that higher scores indicated the more severe lesions. In each experiment, calves immunized with live P haemolytica had lower lesion scores than calves vaccinated with saline solution or bacterin. In 2 of the experiments, the differences were significant (P less than 0.05). In all experiments, calves vaccinated parenterally with a commercial P haemolytica/P multocida bacterin or with a formalin-killed P haemolytica bacterin had lesion scores that were not significantly different (P greater than 0.05) than for control calves vaccinated with saline solution. Live and killed bacterial preparations induced a significant serum antibody response to P haemolytica as measured by a quantitative fluorometric immunoassay. The antibody response to vaccination was not affected by preexisting titers to P haemolytica. Serum antibody titers were not consistently as high for calves vaccinated with bacterins as for calves vaccinated with live organisms. Although high antibody titers correlated with low lesion scores when calves vaccinated with saline solution or live organisms were analyzed collectively, there was not a significant correlation between the 2 variables when calves, vaccinated with saline solution or with bacterin, were analyzed collectively. These data indicate that, although bacterins may induce a detectable serum antibody response, they do not induce protection against transthoracic challenge exposure to P haemolytica.  相似文献