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201.
Neospora caninum is known to cause abortion in cattle. This study demonstrated the presence of specific IgG to Neospora in milk and serum samples obtained from three dairy farms in Georgia and two in Texas. Samples from four hundred fourteen dairy cows were examined using a western blot assay of which 362 were milk and 87 were serum. Samples with antibodies to Neospora were identified in 32.1% (105/327) of the examined animals in Georgia, whereas in Texas it was identified in 10.3% (9/87). Positive Georgia samples were found in 24.4% from farm A (28/115), 21.6% from farm B (30/139), and 64.4% from farm C (47/73). In Texas, 13.5% (7/52) of animals in farm D and 5.71% (2/35) from farm E also had specific antibodies to Neospora. The number of animals from Georgia dairy farms with antibodies to Neospora was significantly higher than the Texas dairy farms. This may be related to the age of the animals examined in this study (more than 2 years old). Antibodies present in sera had excellent agreement with the antibodies present in milk. Collection of milk samples for serological testing is easier and less invasive than obtaining bovine sera, therefore offering an alternative for animal testing. 相似文献
202.
Ortega J Daft B Assis RA Kinde H Anthenill L Odani J Uzal FA 《Veterinary pathology》2007,44(3):269-275
Omphalitis and the resulting septicemia contribute to perinatal mortality in several animal species. In foals, the most important causes of omphalitis are Escherichia coli and Streptococcus zooepidemicus. However to date, no information has been published about the role of Clostridium sordellii in these infections. In this paper, we describe 8 cases of perinatal mortality in foals associated with internal umbilical remnant infection by C. sordellii. The foals studied were between 12 and 21 days old at the time of death, and various breeds were represented in the group. Five of the foals were male and 3 were female. The diagnosis was established on the basis of the detection of C. sordellii by 3 methods (culture, fluorescent antibody test, and immunohistochemistry) and on gross and histopathologic findings. All foals had acute peritonitis, and the internal umbilical remnant was thickened by edema, hemorrhage, and fibrosis. A moderate amount of serosanguinous fluid with fibrin strands was present in the pericardial sac and pleural cavity. Histopathologically, the urachus and umbilical arterial walls were thickened by edema and exhibited hemorrhage, fibrin, and leukocytic infiltration. Gram-positive bacterial rods were observed in subepithelial areas of the urachus, the adventicia of umbilical arteries, and interstitium of the internal umbilical remnant. On the basis of these findings, we suggest that C. sordellii should be considered in the differential diagnosis for infections of the internal umbilical remnant in foals. 相似文献
203.
Buendía AJ Nicolás L Ortega N Gallego MC Martinez CM Sanchez J Caro MR Navarro JA Salinas J 《Veterinary immunology and immunopathology》2007,115(1-2):76-86
Mouse models have been widely used to test candidate vaccines against Chlamydophila abortus infection in mice. Although the induction of a systemic infection by endogenous or intraperitoneal inoculation is a useful tool for understanding the immune mechanism involved in the protection conferred by the vaccination, a different approach is necessary to understand other factors of the infection, such as mucosal immunity or the colonization of target organs. To test whether C. abortus intranasal model of infection in mice is a useful tool for testing vaccines in a first group of experiments mice, were infected intranasally with C. abortus to characterize the model of infection. When this model was used to test vaccines, two inactivated experimental vaccines, one of them adjuvated with QS-21 and another with aluminium hydroxide, and a live attenuated vaccine (strain 1B) were used. Non-vaccinated control mice died within the first 8 days, after displaying substantial loss of weight. Histologically, the mice showed lobar fibrinopurulent bronchointerstitial pneumonia. Prior immunization with QS-21 adjuvated vaccine or 1B vaccine presented mortality and the recipients showed a greater number of T cells in the lesions, especially CD8(+) T cells, than the control mice and mice immunized with vaccine adjuvated with aluminium hydroxide. The results confirm that the C. abortus intranasal model of infection in mice is a useful tool for testing vaccines. 相似文献
204.
Moreno LA González-Gross M Kersting M Molnár D de Henauw S Beghin L Sjöström M Hagströmer M Manios Y Gilbert CC Ortega FB Dallongeville J Arcella D Wärnberg J Hallberg M Fredriksson H Maes L Widhalm K Kafatos AG Marcos A;HELENA Study Group 《Public health nutrition》2008,11(3):288-299
OBJECTIVES: To identify the main knowledge gaps and to propose research lines that will be developed within the European Union-funded 'Healthy Lifestyle in Europe by Nutrition in Adolescence' (HELENA) project, concerning the nutritional status, physical fitness and physical activity of adolescents in Europe. DESIGN: Review of the currently existing literature. RESULTS: The main gaps identified were: lack of harmonised and comparable data on food intake; lack of understanding regarding the role of eating attitudes, food choices and food preferences; lack of harmonised and comparable data on levels and patterns of physical activity and physical fitness; lack of comparable data about obesity prevalence and body composition; lack of comparable data about micronutrient and immunological status; and lack of effective intervention methodologies for healthier lifestyles. CONCLUSIONS: The HELENA Study Group should develop, test and describe harmonised and state-of-the-art methods to assess the nutritional status and lifestyle of adolescents across Europe; develop and evaluate an intervention on eating habits and physical activity; and develop and test new healthy food products attractive for European adolescents. 相似文献
205.
Evaluating the effects of climate change in the southern Benguela upwelling system using the Atlantis modelling framework
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Kelly Ortega‐Cisneros Kevern L. Cochrane Elizabeth A. Fulton Rebecca Gorton Ekaterina Popova 《Fisheries Oceanography》2018,27(5):489-503
The ocean is affected by multiple anthropogenic stressors including climate change, the effects of which are already evident in many ocean ecosystems. The ABACuS v2 end‐to‐end model together with climate projections from the NEMO‐MEDUSA 2.0 model were used to evaluate the effects of fishing, warming and horizontal and vertical mixing on the southern Benguela upwelling system. Of the drivers examined in this study, warming had the greatest effect on species biomass, with mainly negative effects. The magnitude of the impacts of warming intensified from the RCP 2.6 to the 8.5 emission scenario. Fishing negatively affected demersal and large pelagic fish, which in turn resulted in a biomass increase of forage fish due to a decrease in predation pressure. Water mixing was found to have minor indirect effects on zooplankton biomass and fish. The responses of species and species groups to the combined effects of fishing and warming were approximately equally divided between additive, synergistic and antagonistic. Interpretation of our model results suggests that the southern Benguela system is likely to be affected by climate change, including substantial changes in the abundance of some species important to the region's fisheries. Future planning for fisheries needs to take this into account, including through management that strives to maintain the resilience of key species and the system as a whole. In line with previous studies on the southern Benguela, the results reinforce the importance of including consideration of the indirect and combined impacts of climate change and fishing in management and planning. 相似文献
206.
207.
Romn Makarov Carlos Omar Lomelí‐Ortega Lina Anglica Zermeo‐Cervantes Eugenio García‐lvarez Jesús Neftalí Gutirrez‐Rivera Csar Salvador Cardona‐Flix Sergio Francisco Martínez‐Díaz 《Aquaculture Research》2019,50(11):3107-3116
Shrimp culture is a well‐established and fast‐growing industry that produces economic and social benefits in many countries. However, during the last years, it was severely affected by the emergence of the Early Mortality Syndrome (EMS) or Acute Hepatopancreatic Necrosis Disease (AHPND). This disease is mainly attributed to Vibrio parahaemolyticus, and currently, there is no effective cure or treatment. In this study, the use of T2A2 and VH5e bacteriophages was evaluated to control different AHPND‐positive strains (presumptively identified as V. parahaemolyticus, VPAHPND) under laboratory conditions. Lytic effect of T2A2 and VH5e bacteriophages against different strains isolated from AHPND outbreaks was corroborated. In addition, the effectiveness of the mixture of both phages was tested on a brine shrimp experimental infection model using three highly virulent VPAHPND strains. It has been found that phage‐treated brine shrimp had significantly higher survival percentage compared with non‐treated groups (p < .001). Also, phage cocktail was found to be harmless to the organisms. These results suggest that the phage mixture is worth considering as a possible control measure for positive AHPND strains, although it is clear that further and more extensive testing is needed. 相似文献
208.
Lipids and essential fatty acids are determinants of the reproductive process in marine fish, affecting fecundity, egg quality,
hatching performance, pigmentation and larval malformation. We have analyzed and characterized the lipids of eggs and unfed
larvae of two wild caught scombroid fish, the Atlantic northern bluefin tuna (Thunnus thynnus) and Atlantic bonito (Sarda sarda). Dry matter and total lipid contents, polar and neutral lipid classes and total lipid fatty acid contents were determined
in the eggs of bluefin tuna and eggs and unfed larvae during the development of Atlantic bonito. Bluefin tuna eggs had slightly
but significantly more dry mass than bonito eggs but very similar lipid content. However, bluefin tuna eggs presented a higher
polar lipid content due to increased proportions of phosphatidylethanolamine (PE), phosphatidylserine (PS) and phosphatidylinositol
(PI). Bonito eggs and larvae showed increasing dry mass and decreasing lipid content with development. The proportion of polar
lipids increased due to increased PE, PS and PI, whereas choline-containing polar lipids (phosphatidylcholine and sphingomyelin)
remained relatively constant. Free cholesterol also increased, whereas the levels of other neutral lipids, especially triacylglycerol
and steryl ester fractions, decreased, presumably due to utilization for energy to drive development. Bluefin tuna eggs had
higher levels of n − 3 and n − 6 highly unsaturated fatty acids due to higher docosahexaenoic and arachidonic acid contents, respectively, than bonito eggs.
The results are discussed in relation to the lipid and fatty acid requirements of larval scombroid fish in comparison to those
of other larval marine finfish species under culture conditions. 相似文献
209.
Mónica B. Betancor Aurelio Ortega Fernando de la Gándara Douglas R. Tocher Gabriel Mourente 《Fish physiology and biochemistry》2017,43(2):493-516
The present study is the first to evaluate lipid metabolism in first-feeding Atlantic bluefin tuna (ABT; Thunnus thynnus L.) larvae fed different live prey including enriched rotifers Brachionus plicatilis and Acartia sp. copepod nauplii from 2 days after hatch. Understanding the molecular basis of lipid metabolism and regulation in ABT will provide insights to optimize diet formulations for this high-value species new to aquaculture. To this end, we investigated the effect of dietary lipid on whole larvae lipid class and fatty acid compositions and the expression of key genes involved in lipid metabolism in first feeding ABT larvae fed different live prey. Additionally, the expression of lipid metabolism genes in tissues of adult broodstock ABT was evaluated. Growth and survival data indicated that copepods were the best live prey for first feeding ABT and that differences in growth performance and lipid metabolism observed between larvae from different year classes could be a consequence of broodstock nutrition. In addition, expression patterns of lipid metabolic genes observed in ABT larvae in the trials could reflect differences in lipid class and fatty acid compositions of the live prey. The lipid nutritional requirements, including essential fatty acid requirements of larval ABT during the early feeding stages, are unknown, and the present study represents a first step in addressing these highly relevant issues. However, further studies are required to determine nutritional requirements and understand lipid metabolism during development of ABT larvae and to apply the knowledge to the commercial culture of this iconic species. 相似文献
210.
Raúl Ortega Isabel Miralles David Erik Meca Juan Carlos Gázquez Miguel Ángel Domene 《Communications in Soil Science and Plant Analysis》2016,47(10):1216-1226
Nowadays farmers are interested in moving to organic cultivation. The purpose of this experiment was to compare two organic, with or without effective microorganisms (EM), and one conventional greenhouse pepper cropping systems. We focused on the study of the macronutrients nitrogen, phosphorus, and potassium (N, P, K) concentrations in leaves plants, soil, and soil solution during the full production cycle to detect any plant nutrient deficiencies and differences in crop yield for the three different treatments. Foliar analyses showed good concentrations of nutrients with conventional treatment, but P was low with organic ones. However, P content in soil was high, because this element is easily precipitated in carbonated soil. Pepper yield was higher in conventional treatment and no differences in productivity were found between the two organic treatments. The role of EM was not clear on the development of plants and fruits; however it seems to influence the N mineralization in organic treatments. 相似文献