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101.
Megan E. Pozza Thattawan Kaewsakhorn Chumnan Trinarong Nongnuch Inpanbutr Ramiro E. Toribio 《Veterinary journal (London, England : 1997)》2014,199(3):451-456
Vitamin D is essential in calcium and phosphorus regulation, bone physiology, cell proliferation and epithelial integrity. Literature on vitamin D in growing horses is sparse, and the effect of age on vitamin D has not been evaluated in equids in the United States or in tropical countries. The goal of this study was to determine if there was an effect of age on serum 25(OH)D3 concentrations in equids in the US (Ohio/Kentucky) and Thailand (Chiang Rai and Kanchanaburi) during the same time of the year. Blood samples were collected from healthy ponies (n = 21) and Thoroughbred foals (n = 13), yearlings (n = 10), and horses (n = 20) in Thailand and from Thoroughbred foals (n = 10) and horses (n = 17) in the US. Serum concentrations of 25(OH)D3, calcium and phosphorus were measured.In both countries, serum 25(OH)D3 concentrations were lower in foals than in yearlings and adult horses. Serum 25(OH)D3 concentrations were higher in horses than in ponies in Thailand, but were not different between horses from either country. Calcium concentrations were not different between groups or location. In both countries, phosphorus concentrations were higher in foals than in older groups; however, were not different between ponies and horses. This study shows that independent of geography there are age-related differences in 25(OH)D3 concentrations in horses and further confirms that 25(OH)D3 concentrations are lower in horses compared to other species. The information will serve as the basis for future clinical studies and to help understand better the pathophysiology of equine disorders associated with calcium and phosphorus dysregulation. 相似文献
102.
The intestine and the gut-associated lymphoid tissue (GALT) are essential components of whole body immune defense, protecting the body from foreign antigens and pathogens, while allowing tolerance to commensal bacteria and dietary antigens. The requirement for protein to support the immune system is well established. Less is known regarding the immune modifying properties of individual amino acids, particularly on the GALT. Both oral and parenteral feeding studies have established convincing evidence that not only the total protein intake, but the availability of specific dietary amino acids (in particular glutamine, glutamate, and arginine, and perhaps methionine, cysteine and threonine) are essential to optimizing the immune functions of the intestine and the proximal resident immune cells. These amino acids each have unique properties that include, maintaining the integrity, growth and function of the intestine, as well as normalizing inflammatory cytokine secretion and improving T-lymphocyte numbers, specific T cell functions, and the secretion of IgA by lamina propria cells. Our understanding of this area has come from studies that have supplemented single amino acids to a mixed protein diet and measuring the effect on specific immune parameters. Future studies should be designed using amino acid mixtures that target a number of specific functions of GALT in order to optimize immune function in domestic animals and humans during critical periods of development and various disease states. 相似文献
103.
Lídia Gual-Gonzalez Maggie S. J. McCarter Megan Peebles Melissa S. Nolan 《Zoonoses and public health》2023,70(1):103-110
Animal rabies cases have increased steadily in South Carolina (SC) for the past decade. An understanding of the population's awareness and understanding of the disease is needed to tailor public health interventions. A marketing list-serv of SC residents' email addresses was used to recruit anonymous respondents for a Knowledge Attitudes and Practices (KAP) electronic survey. A total 516 South Carolinians completed the 31-question survey. Quantile regression and a Pearson's correlation evaluated potential associations between respondent's rabies knowledge and their attitudes and practices. Knowledge was assessed on topics of rabies biology, state animal case counts and rabies pet-related laws. Level of concern and level of knowledge were positively correlated. Additionally, statewide hotspot analysis revealed geographic areas warranting targeted public health interventions; counties with low public concern juxtapositioned with high animal rabies case counts. This study demonstrates the utility of statewide KAPs to gauge populations rabies perception and related preventative actions to tailor appropriate educational programs to limit human-animal rabies exposures. 相似文献
104.
Fine root electrolyte leakage and moisture content: indices of Sitka spruce and Douglas-fir seedling performance after desiccation 总被引:1,自引:0,他引:1
In spring 1992, 2-year-old bare-rooted seedlings of Sitka spruce (Picea sitchensis (Bong.) Carr.) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) were exposed for 0, 0.5, 1.0, 1.5, or 3 h in a controlled environment room at 20°C. Plants were desiccated in batches during February and March; 100 seedlings of each species were planted in 5 20-plant plots at each of 6 planting sites using the normal planting times and methods of each area. The effect of exposure was assessed within 24 h of desiccation on a subsample of plants by measuring fine root moisture content and electrolyte leakage and, in a limited number of cases, needle water potential. These measures were related to survival and growth after the first and second growing seasons.There were significant interactions between the effect of desiccation and site. The measurements following desiccation were significantly related to survival and growth on some but not all sites; in general, the effect of condition was more pronounced on sites with low spring rainfall than on sites with greater than 100 mm rainfall per month during the spring of planting. Root electrolyte leakage was significantly related to performance in slightly more cases than needle water potential or root moisture content. 相似文献
105.
106.
Megan Carney 《Agriculture and Human Values》2012,29(2):185-201
Santa Barbara County exhibits some of the highest rates of food insecurity in California, as well as in the United States. Through ethnographic research of three low-income, predominantly Latino communities in Santa Barbara County, this study examined the degree to which households had been experiencing heightened levels of food insecurity since the economic recession and ensuing coping strategies, including gender-specific repercussions and coping strategies. Methods included administering a survey with 150 households and conducting observation and unstructured interviews at various local food-centered venues. Results indicated that households from the three communities were experiencing heightened levels of food insecurity and that all three communities were employing diversification of procurement, adjustments to a reduced or limited food budget, reliance on food assistance, and revitalization of the home as a site of domestic food production and preparation as coping strategies. The results also suggested that women suffered disproportionately higher psychological and physical costs associated with compounding crises. In conclusion, the experiences narrated by low-income households reflect a form of citizenship that appears compromised by a host of variables perceived to exist outside the realm of local control. Shifting toward an operational framework of food sovereignty may allow these communities to become more resilient in the face of future political, environmental, social, and economic stressors. 相似文献
107.
Megan I. Gerber Ann M. Swinker W. Burton Staniar Jacob R. Werner Edward A. Jedrzejewski Ann L. Macrina 《Journal of Equine Veterinary Science》2012
The objectives of this study were to characterize the inflammatory response after microchip insertion, evaluate pain response and swelling at the microchip insertion site, and measure migration of the microchips. Eighteen mature Quarter Horse mares were separated by expected parturition dates and then assigned randomly to treatment groups. The microchip group (n = 7) had microchips inserted using a sterile needle and syringe; the sham group (n = 7) had a needle inserted but no microchip; and the control group (n = 4) had no insertion. The inflammatory response was measured over a 2-week period by measuring dermal temperature, response to pressure, and swelling at the insertion site and plasma serum amyloid A (SAA). For the migration component of the study, radiographs of the seven microchipped horses were taken over 6 months after insertion. These radiographs allowed measurement between a select vertebral point and the microchip. The microchip and sham insertion did not cause a detectable increase in temperature. Algometer readings, used to quantify pressure necessary to induce a pain threshold response, indicated that microchip insertion area was more sensitive than sham insertion at 2 hours, day 1, and day 3 post insertion. Visible swelling began 2 hours postinsertion and resolved by day 3. SAA concentrations were affected by day following insertion, but not by treatment group. Increases in SAA concentration could not be matched with local insertion reactions. Migration was not detected in any of the horses during the 6 months within a 0.7-cm margin of error. 相似文献
108.
IV lipid emulsion (ILE) therapy is emerging as a potential antidote for lipophilic drug toxicities in both human and veterinary medicine. ILE has already gained acceptance in human medicine as a treatment of local anesthetic systemic toxicity, but its mechanism of action, safety margins, and standardized dosing information remains undetermined at this time. Experimental and anecdotal use of ILE in the human and veterinary literature, theorized mechanisms of action, current dosing recommendations, potential adverse effects, and indications for use in human and veterinary emergency medicine are reviewed herein. 相似文献
109.
110.
Francisca Samsing Megan Rigby Hedda K. Tengesdal Richard S. Taylor Daniela Farias Richard N. Morrison Scott Godwin Carla Giles Jeremy Carson Chloe J. English Roger Chong James W. Wynne 《Journal of fish diseases》2021,44(1):73-88
The Tasmanian salmon industry had remained relatively free of major viral diseases until the emergence of pilchard orthomyxovirus (POMV). Originally isolated from wild pilchards, POMV is of concern to the industry as it can cause high mortality in farmed salmon (Salmo salar). Field observations suggest the virus can spread from pen to pen and between farms, but evidence of passive transmission in sea water was unclear. Our aim was to establish whether direct contact between infected and naïve fish was required for transmission, and to examine viral infection dynamics. Atlantic salmon post‐smolts were challenged with POMV by either direct exposure via cohabitation or indirect exposure via virus‐contaminated sea water. POMV was transmissible in sea water and direct contact between fish was not required for infection. Head kidney and heart presented the highest viral loads in early stages of infection. POMV survivors presented low viral loads in most tissues, but these remained relatively high in gills. A consistent feature was the infiltration of viral‐infected melanomacrophages in different tissues, suggesting an important role of these in the immune response to POMV. Understanding POMV transmission and host–pathogen interactions is key for the development of improved surveillance tools, transmission models and ultimately for disease prevention. 相似文献