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排序方式: 共有217条查询结果,搜索用时 265 毫秒
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Xunde Li Kristopher A. Flores Sheila Barry Theresa A. Becchetti Morgan Doran Julie A. Finzel Royce Larsen David Lile Neil McDougald Tran Nguyen Chengling Xiao Edward R. Atwill 《Strength and Conditioning Journal》2019,72(3):461-466
Cryptosporidium spp. and Giardia duodenalis are common protozoal parasites in livestock including beef cattle on rangeland and irrigated pasture. A statewide cross-sectional study was conducted to determine the prevalence, species or genotype, and risk factors for fecal shedding of Cryptosporidium and Giardia by cattle from California cow-calf operations. Species and genotypes of Cryptosporidium and Giardia were determined by molecular fingerprinting. Prevalence of Cryptosporidium (19.8%) and Giardia (41.7%) in fecal samples from calves were approximately twice as high as fecal samples from cows (9.2% and 23.1%, respectively). In addition to age, multivariable logistic regression showed that higher stocking density and a higher number of replacement heifers were positively associated with fecal shedding of Cryptosporidium while longer calving interval, a winter/spring calving season, and higher numbers of replacement heifers were positively associated with shedding of Giardia. The dominant species and genotypes of Cryptosporidium and Giardia in feces from these cow-calf herds were Cryptosporidium ryanae (75%) and assemblage E for Giardia duodenalis (90%), which have low impact on public health compared with other zoonotic species/genotypes of these two parasites. We identified host and potential management practices that can be used to protect cattle health and reduce the risk of surface water contamination with protozoal parasites from cow-calf operations. In addition, this work updated the scientific data regarding the predominance of low zoonotic genotypes of Cryptosporidium and Giardia shed in the feces of commercial cow-calf herds on California rangeland and irrigated pasture. 相似文献
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The potential of peptidase-containing bran extracts from germinated cereals (wheat, emmer, barley) and a peptidase preparation from Aspergillus niger (AN-PEP) to degrade gluten in wheat starch below the threshold for gluten-free foods of 20 mg/kg was compared. The gluten-specific peptidase activity of the peptidases was determined by using gliadin as a protein-based substrate as well as the two celiac-active peptides PQPQLPYPQPQLPY (α-gliadin) and SQQQFPQPQQPFPQQP (γ-hordein). The peptidase activity of AN-PEP exceeded the activities of bran from germinated cereals by a factor up to 690,000. Three wheat starches with initial gluten contents of 110, 1679, and 2070 mg/kg, respectively, were incubated with bran extracts and AN-PEP, lyophilized, and residual gluten was quantitated by a competitive ELISA. Unlike peptidases from bran extracts, AN-PEP was capable of degrading gluten below 20 mg/kg in all starches. The absence of gluten in AN-PEP-treated starches was confirmed by liquid-chromatography-mass spectrometry. The properties of gluten-free starches were comparable to the native starches with the exception of a reduced viscosity after AN-PEP treatment. This problem could be overcome by using higher enzyme concentrations and shorter incubation times or by optimizing AN-PEP production for lower residual α-amylase activity. 相似文献
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Laura Elizabeth Joan Huson Edith Authié Alain Fran?ois Boulangé James Phillip Dean Goldring Theresa Helen Taillefer Coetzer 《Veterinary research》2009,40(6)
The protozoan parasite Trypanosoma congolense is the main causative agent of livestock trypanosomosis. Congopain, the major lysosomal cysteine proteinase of T. congolense, contributes to disease pathogenesis, and antibody-mediated inhibition of this enzyme may contribute to mechanisms of trypanotolerance. The potential of different adjuvants to facilitate the production of antibodies that would inhibit congopain activity was evaluated in the present study. Rabbits were immunised with the recombinant catalytic domain of congopain (C2), either without adjuvant, with Freund’s adjuvant or complexed with bovine or rabbit α2-macroglobulin (α2M). The antibodies were assessed for inhibition of congopain activity. Rabbits immunised with C2 alone produced barely detectable anti-C2 antibody levels and these antibodies had no effect on recombinant C2 or native congopain activity. Rabbits immunised with C2 and Freund’s adjuvant produced the highest levels of anti-C2 antibodies. These antibodies either inhibited C2 and native congopain activity to a small degree, or enhanced their activity, depending on time of production after initial immunisation. Rabbits receiving C2-α2M complexes produced moderate levels of anti-C2 antibodies and these antibodies consistently showed the best inhibition of C2 and native congopain activity of all the antibodies, with maximum inhibition of 65%. Results of this study suggest that antibodies inhibiting congopain activity could be raised in livestock with a congopain catalytic domain-α2M complex. This approach improves the effectiveness of the antigen as an anti-disease vaccine candidate for African trypanosomosis. 相似文献
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Slocum T 《Journal of the American Veterinary Medical Association》2006,228(2):195; author reply 196
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Yoo S Baranowski T Missaghian M Baranowski J Cullen K Fisher JO Watson K Zakeri IF Nicklas T 《Public health nutrition》2006,9(3):384-393
OBJECTIVES: To identify the most common frequency of food-purchasing patterns and relate this pattern to characteristics of individuals and families.DESIGN: A customer-intercept survey was conducted in the greater Houston area, Texas, USA, in 2002. The frequency of food shopping at supermarkets, convenience stores and restaurants to buy food for eating at home was assessed.SUBJECTS: A total of 823 adults (78.5% female; mean age 37.4 years) who went to any of several grocery or convenience stores, including European, Hispanic and African Americans, and Asian/Pacific Islanders.RESULTS: Major food-shopping patterns were a weekly big trip with a few small trips (34.9%), biweekly big trips with a few small trips (21.9%), no big shopping trips (15.4%), a weekly big trip without small trips (13.9%), a monthly big trip (8.3%), and biweekly big trips without small trips (6.4%). While 61.1% of participants never went to convenience stores to buy fruit and vegetables (F&V) for eating at home, 67% went to restaurants for F&V. African American families shopped for food least frequently, while Asian American families shopped for food most frequently. Educational level was negatively associated with the use of convenience stores and positively associated with take-away from restaurants.CONCLUSIONS: There is substantial variability in the frequency of food shopping. Future research on food shopping should incorporate this variable. 相似文献
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Lupu M Sullivan EW Westfall TE Little MT Weigler BJ Moore PF Stroup PA Zellmer E Kuhr C Storb R 《Journal of the American Veterinary Medical Association》2006,228(5):728-732
CASE DESCRIPTION: A 7-year-old Golden Retriever was examined because of anorexia, lethargy, vomiting, and gradual weight loss. CLINICAL FINDINGS: Splenomegaly, pancytopenia, high serum calcium concentration, and high alkaline phosphatase activity were detected. Magnetic resonance imaging revealed an enlarged mesenteric lymph node and increased signals from the bone marrow of the ilium and vertebral bodies. Histologic examination and immunophenotyping of biopsy specimens confirmed a stage V (b) T-cell malignant lymphoma. TREATMENT AND OUTCOME: Clinical remission was attained by use of 2 chemotherapy cycles, followed by an allogeneic hematopoietic cell transplant performed at 18 weeks after diagnosis. A donor was identified by molecular dog leukocyte antigen typing methods. The patient was conditioned with 2 fractions of 4 Gy total body irradiation delivered 3 hours apart at 7 cGy/min, followed by an IV infusion of recombinant canine granulocyte colony-stimulating factor mobilized leukapheresis product and postgrafting immunosuppression with cyclosporine. Chimerism analyses revealed full donor engraftment that has been maintained for at least 58 weeks after transplant. Remission has been confirmed by normal results of serum thymidine kinase assays and the absence of peripheral blood clonal T-cell receptor gene rearrangements. CLINICAL RELEVANCE: Systemic chemotherapy induces remissions; however, most dogs succumb to disease recurrence because of multidrug resistance. Outcome of allogeneic hematopoietic cell transplantation in dogs can be excellent because of improved donor-recipient selection by use of molecular dog leukocyte antigen typing, compared with early attempts, and better prevention of graft versus host disease, better supportive care, and substitution of peripheral blood mononuclear cells for bone marrow. 相似文献