The effect of cyclopiazonic acid on the development of pale, soft, and exudative pork from pigs of defined malignant hyperthermia genotype     

Byrem TM  Booren AM  Hill GM  Chu FS  Strasburg GM 《Journal of animal science》1999,77(1):166-172

Malignant hyperthermia (MH) and the mycotoxin cyclopiazonic acid (CPA) are each associated with abnormal calcium homeostasis in skeletal muscle, a key underlying factor in the development of pale, soft, and exudative (PSE) pork. To determine whether the natural presence of CPA in livestock feed ingredients contributes to the varying incidence of PSE in the pork industry, various levels of CPA (.1 to 50 mg/kg of diet) were included in the diets of market weight hogs (n = 52) of defined malignant hyperthermia genotype (NN = normal, Nn = a MH carrier, and nn = MH-positive). Animals with two copies of the MH mutation (nn) displayed improved live animal performance compared with NN and Nn animals (increased feed intake, average daily gain, and feed efficiency) but yielded lower quality loin chops as indicated by lower 45-min pH (P<.01), higher Commission Internationale de l'Eclairage (CIE) L* color coordinate values (P<.05), and higher drip losses (P<.01). The effects of CPA varied. In the first feeding trial, conducted under normal outside temperatures (2 degrees C), CPA had no effect (P> .2) on either live animal performance or meat quality. During the second trial, conducted under extreme outside temperatures (-18 degrees C), CPA-dependent reductions (P<.05) in feed intake, average daily gain, and 45-min pH in nn hogs support the possibility of interactions between malignant hyperthermia and dietary CPA on skeletal muscle calcium homeostasis and the development of PSE pork. These results suggest that this interaction may require stressful environmental conditions or the ingestion of CPA doses much higher than occur under natural conditions.  相似文献   

北京栽培白蘑菇病害的研究   总被引：3，自引：0，他引：3  

朱慧贞 《植物病理学报》1982,12(3):54-58

 1979~1980年进行箱式栽培白蘑菇的试验,并同时调查对比病害发生情况,和采用各种措施的效果。  相似文献   

Recombinant equine growth hormone administration: effects on synovial fluid biomarkers and cartilage metabolism in horses     

Dart AJ  Little CB  Hughes CE  Chu O  Dowling BA  Hodgson DR  Rose RJ  Johnson KA 《Equine veterinary journal》2003,35(3):302-307

REASONS FOR PERFORMING STUDY: Recombinant equine growth hormone (reGH) has recently been evaluated for effects on body condition and wound healing. It has the potential to influence articular cartilage via stimulation of IGF-1. OBJECTIVES: To investigate effects of administration on synovial joint metabolism. METHODS: Six mature horses were given 20 microg/kg bwt reGH daily for 8 weeks by i.m. injection. Three control horses were injected with sterile water. Serum and synovial fluid samples were collected at 6, 8, 11 and 16 weeks for GH and IGF-1 assays. Articular cartilage harvested at week 16 was evaluated by Western analysis using monoclonal antibodies BC-13, BC-4, 8-A-4 and CH-3. RESULTS: Concentrations of IGF-1 in serum and synovial fluid were significantly elevated (P < 0.05) at 6 and 8 weeks in the reGH group. Glycosaminoglycan concentrations in synovial fluid were significantly less than controls at these time points, suggesting that reGH may modulate proteoglycan metabolism in articular cartilage. In the reGH group, there were not any alterations in synovial fluid content of 3B3(-) epitope or aggrecan metabolite, or in aggrecan or link protein catabolites retained within cartilage, that might be expected with development of osteoarthritis. CONCLUSIONS: Intramuscular administration of reGH may be a more efficient means of delivery of IGF-1 to joints for cartilage resurfacing initiatives. POTENTIAL RELEVANCE: We found no alterations in cartilage metabolism indicative of development of osteoarthritis.  相似文献   

Effect of tumor infiltrating lymphocytes on the expression of MHC molecules in canine transmissible venereal tumor cells     

Hsiao YW  Liao KW  Hung SW  Chu RM 《Veterinary immunology and immunopathology》2002,87(1-2):19-27

Canine transmissible venereal tumor (CTVT) can be allo-transplanted across major histocompatibility complex barriers. The expression of MHC molecules is usually low in the progression (P) stage and then greatly increases during tumor regression (R). We investigated the effects of tumor infiltrating lymphocytes (TIL) on the expression of MHC molecules of CTVT cells. Isolated, viable CTVT cells were inoculated at each of 12 sites (1 x 10(8) CTVT cells per site) on the back of six, mixed-breed dogs. Tumor masses were collected every 2-3 weeks and prepared for histopathologic, immunocytochemistry, flow cytometry and immunoblotting studies. The level of MHC expression on tumor cells from different stages of growth was measured. Initially, expression of MHC I and II molecules in P phase CTVT was low. Twelve weeks post-inoculation (PI), expression increased dramatically and it continued to increase during R phase. Tumor growth slowed after 12 weeks PI and tumors entered R phase around 17 weeks PI. We hypothesize that CTVT evades host immunosurveillance and grows progressively for 12 weeks, when it becomes vulnerable and subject to the host's anti-tumor immune responses. We further demonstrated that R phase, but not P phase, TIL were closely associated with the over-expression of MHC I and II molecules by CTVT cells. The number and proportion of TIL were higher in R phase tumors. Supernatants, from R phase co-cultures (CTVT+TIL) and TIL only, promoted MHC I and II expression on P phase CTVT cells. After culturing alone for 1 month, expression of MHC classes I and II molecules in R phase CTVT cells decreased to the level of P phase CTVT cells. However, the above-mentioned supernatants restored their expression of MHC I and II molecules. In contrast, supernatants from P phase TIL or CTVT cells increased expression slightly or had no effect. Therefore, TIL, not CTVT cells, produce the effective substance (s) to promote the expression of MHC molecules by the tumor cells. Heat treated supernatant was unable to promote the expression of MHC I and II molecules by CTVT cells. In conclusion, TIL isolated from R phase CTVT secreted a heat-sensitive, soluble substance(s) that triggered over-expression of MHC I and II after 12 weeks PI. This caused the tumor to enter R phase and helped stop CTVT growth. Our findings will facilitate the understanding and further investigation of the mechanisms that initiate host immune surveillance against tumors.  相似文献   

孝感市农药市场管理现状及对策     

丁金元  楚天敏  聂琪 《湖北植保》2007,(3):9-10

1997年5月8日,国务院发布实施《农药管理条例》,明确赋予农业行政主管部门负责农药监督管理工作。孝感市农业局授权孝感市农药监督管理站具体承担监督管理任务。几年来,由于各级农业行政主管部门高度重视,各级农药管理部门积极开展工作,取得了明显的成效。突出表现在全市农药市  相似文献   

Comparison of ambisense m RNA of watermelon silver mottle virus with other tospoviruses     

Chu FH  Yeh SD 《Phytopathology》1998,88(4):351-358

ABSTRACT Double-stranded genomic RNAs (dsRNAs) extracted from Chenopodium quinoa infected with watermelon silver mottle virus (WSMV) were similar to those of tomato spotted wilt virus (TSWV, serogroup I) and impatiens necrotic spot virus (INSV, serogroup III), except that the S dsRNA of WSMV is 0.75 and 0.6 kbp longer than those of TSWV and INSV, respectively. The complete nucleotide sequence of the genomic M RNA of WSMV was determined from cDNA clones generated from separated M dsRNA. The M RNA is 4,880 nucleotides in length with two open reading frames (ORFs) in an ambisense organization. The M RNA-encoded nonstructural (NSm) ORF located on the viral strand encodes a protein of 312 amino acids (35 kDa), and the G1/G2 ORF located on the viral complementary strand encodes a protein of 1,121 amino acids (127.6 kDa). The RNA probe corresponding to the NSm or G1/G2 ORF of WSMV failed to hybridize with the M dsRNAs of TSWV and INSV. Comparison of M and S RNAs of WSMV, TSWV, INSV, and peanut bud necrosis virus (PBNV, serogroup IV) revealed a consensus sequence of eight nucleotides of 5'-AGAGCAAU...-3' at their 5' ends and 5'-...AUUGCUCU-3' at their 3' ends. The low overall nucleotide identities (56.4 to 56.9%) of the M RNA and the low amino acid identities of the NSm and G1/G2 proteins (30.5 to 40.9%) with those of TSWV and INSV indicate that WSMV belongs to the Tospovirus genus but is phylogenetically distinct from viruses in serogroups I and III. The M RNA of WSMV shares a nucleotide identity of 79.6% with that of PBNV, and the two viruses share 83.4 and 88.7% amino acid identities for their NSm and G1/G2 proteins, respectively. It is concluded that they are two related but distinct species of serogroup IV. In addition to the viral or viral complementary full-length M RNA, two putative RNA messages for the NSm gene and the G1/G2 gene, 1.0 and 3.4 kb, respectively, were detected from the total RNA extracted from WSMV-infected tissue of Nicotiana benthamiana. The 1.0- and 3.4-kb RNAs were also detected in the viral RNAs extracted from purified nucleocapsids, suggesting that the putative messages of the M RNA of WSMV can also be encapsidated by the nucleocapsid protein.  相似文献   

“龙江清酒”的加工与营销策略     

孙楚  杨辉 《黑龙江农业科学》2013,(8)

为研制并开发地产新饮品，以黑龙江地产稻米为原料，采取制酒的工艺流程，研制香气独特的龙江清酒。提出了龙江清酒的加工工艺及技术要点，并策划了该产品的营销策略。加工工艺关键是筛选优良的酒曲霉菌和特定酵母菌、优化制曲工艺和发酵工艺条件等；营销关键是打品牌、强宣传、重营销。  相似文献   

姥山马尾松1代种子园良种选育     

秦国峰  徐高建 《浙江林业科技》1999,19(6):37-42

经过１０多年努力，姥山马尾松１代无性系种子园建成投产，经造林测定，６年生子代林的树高、胸径、村积生长量分别比对照提高１５．２％、１８．４％、５６．８％．良种效益显著，并经浙江省林木良种审定委员会审定通过。  相似文献   

秋延迟中小棚芹菜栽培技术   总被引：2，自引：0，他引：2  

楚继承  曹恒瑞  陈会宽 《北京农业》2010,(30)

中小棚秋延后芹菜是河南省蔬菜的主要栽培类型,栽培好延后的芹菜需要选用适宜品种,培育壮苗,秧苗基本达到适龄壮苗标准,应及时安排定植,覆盖草苫等不透明覆盖物后,要根据天气状况及时揭盖草苫、苇毛苫,当芹菜植株高达60.0cm以上时,可根据市场需要,选晴暖天气收获上市。  相似文献   

绵羊BMP15基因FecXL突变的检测     

储明星  孙洁  陈宏权  方丽 《勤云标准版测试》2007,(10)

【目的】旨在寻找与产羔数相关的遗传标记,为绵羊高繁殖力的标记辅助选择提供科学依据。【方法】以控制Lacaune绵羊高繁殖力的骨形态发生蛋白15(bonemorphogenetic protein15,BMP15)基因为候选基因,采用PCR-SSCP方法在绵羊(Ovisaries)高繁殖力品种(小尾寒羊和湖羊)和低繁殖力品种(多赛特、特克塞尔、考力代、杜泊、南非肉用美利奴和中国美利奴绵羊)中检测BMP15基因的FecXL突变,同时研究该基因突变对小尾寒羊和湖羊高繁殖力的影响。【结果】这8个绵羊品种都没有发生与Lacaune绵羊相同的FecXL突变(C53Y)。【结论】BMP15基因中影响Lacaune绵羊高繁殖力的突变位点对小尾寒羊和湖羊的高繁殖力都没有显著影响。  相似文献