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排序方式: 共有442条查询结果,搜索用时 15 毫秒
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Olga Blanco Prieto Jaime Cataln Marcel Lleonart Sergi Bonet Marc Yeste Joan E. Rodríguez‐Gil 《Reproduction in domestic animals》2019,54(8):1145-1148
A survey of in vivo fertility data from 31 pig farms distributed worldwide was conducted to determine whether stimulating boar semen with LED‐based red light increases its reproductive performance following artificial insemination (AI). Red‐light stimulation with MaXipig® was found to increase farrowing rates (mean ± SEM, control: 87.2% ± 0.4% vs. light stimulation 90.3% ± 0.5%) and the number of both total and live newborn piglets. Red‐light stimulation increased farrowing rates in 27 farms, with an increase ranging from 0.2% to 9.1%. Similar results were observed in litter sizes. Suboptimal management after AI was suggested in those farms with no response to red‐light stimulation. Our results indicate that a routine use of red‐light stimulation of boar semen can have a positive effect on the reproductive performance. However, the effectiveness of this system appears to highly rely upon proper management of pig farms. 相似文献
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Birkenheuer AJ Le JA Valenzisi AM Tucker MD Levy MG Breitschwerdt EB 《Journal of the American Veterinary Medical Association》2006,228(4):568-571
OBJECTIVE: To describe the demographic and clinical characteristics of feline cytauxzoonosis in the mid-Atlantic states and compare the Cytauxzoon felis 18S rRNA gene sequences from affected cats with sequences reported from affected cats in other regions. DESIGN: Retrospective case series. ANIMALS: 34 cats with C. felis infection. PROCEDURE: Medical records of cats in which C. felis infection was diagnosed from May 1998 through June 2004 were reviewed; data collected included signalment, month of diagnosis, geographic location, clinicopathologic abnormalities, medical treatments, outcome, and necropsy findings when applicable. Cytauxzoon felis DNA was amplified, cloned, and sequenced from 4 of these cats and compared with previously reported C. felis DNA sequences. RESULTS: Of 34 C. felis-infected cats, 28 resided in North Carolina, 3 resided in South Carolina, and 3 resided in Virginia; in 32 cats, a diagnosis of C. felis infection was made in April through September. Pancytopenia and icterus were the most common clinicopathologic abnormalities. Thirty-two cats either died or were euthanatized, and 2 cats survived. At 5 veterinary hospitals, multiple cases were identified, and 4 multicat households had > 1 cat infected with C. felis. The 18S rRNA gene sequences characterized in organisms obtained from 4 cats were nearly identical to C. felis DNA sequences reported from other US regions. CONCLUSIONS AND CLINICAL RELEVANCE: Data indicate that veterinarians in the mid-Atlantic region of the United States should consider C. felis infection in cats that become ill with fever, icterus, and pancytopenia or bicytopenia, especially in the spring and summer months. 相似文献
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Jaime Maldonado Pere Riera Marta Sitja Narcis Saubi Enric Espuna Carlos Artigas 罗天海 《国外畜牧学(猪与禽)》2006,26(6):35-38
本文报道了对西班牙养猪密集地区进行的猪流感病毒(SIV)血清学和病毒学调查结果,其目的是检测H1N2亚型猪流感病毒是否和在欧洲其它地区一样也流行于这些地区。在西班牙北部和东部地区100个未接种猪流感疫苗的繁育群采集了600份母猪血清,以进行抗H1N1、H3N2和H1N2亚型病毒的血凝抑制试验(HI);再借助鸡胚病毒分离法和商品薄膜免疫分析法,对采自有呼吸道疾患的225份病猪肺样本进行检测以确定是否存在猪流感病毒。通过HI和逆转录酶-聚合酶链式反应(RT-PCR)方法,再辅以cDNA部分序列的测定,对分离毒株进行鉴定。对血清所作的HI试验表明,在83%受测猪群和76·3%受测猪中至少存在抗一种猪流感病毒亚型的抗体。在受检的600份母猪血清中,仅含抗H1N2、H3N2或H1N1亚型病毒抗体的样本数分别为109份(占总样本比例的18·2%)、60份(10%)和41(6·8%)。从有呼吸道疾患的猪肺样本中分离到12株H3N2亚型病毒、9株H1N1亚型病毒和1株H1N2病毒。对H1N2亚型分离株的神经氨酸酶基因436个核苷酸序列进行的分析,进一步证实了其身份。显然,猪流感依然流行于所研究猪群中,同时一种新的亚型病毒(即H1N2亚型病毒)可能正在开始流行,并且也在西班牙引起了临床发病。 相似文献
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Jaime Rábago‐Castro Jesús Genaro Sánchez‐Martínez Jorge Loredo‐Osti Ricardo Gomez‐Flores Patricia Tamez‐Guerra Carlos Ramírez‐Pfeiffer 《Journal of the World Aquaculture Society》2011,42(3):406-411
Studies in cage‐cultured fish have reported spatial and temporal variations on parasite prevalence; however, most of these studies have been carried out in cold water and marine environments. Channel catfish, Ictalurus punctatus, is the main floating cages‐raised species used in intensive fish culture in Tamaulipas. In Mexico, there are no seasonal reports on fish parasites in this type of cage system. The aim of the present study was to determine the prevalence and mean intensity of ectoparasites of cage‐cultured channel catfish in a year. Fish were sampled bimonthly from six locations in Tamaulipas and measured and evaluated for ectoparasites. Results showed the presence of two gill‐dwelling metazoans, Ligictaluridus floridanus and Ergasilus cerastes and one skin‐dwelling protozoan, Trichodina sp.; a pattern characterized by peaks in prevalence in early autumn for L. floridanus and late autumn for E. cerastes was observed. In addition, geographic location had a significant effect on the prevalence of L. floridanus and E. cerastes. It was also observed that presence of these parasites was not associated with any fish mortality. To our knowledge, this is the first seasonal study on ectoparasite prevalence on channel catfish reared in cages in México. 相似文献
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Marcelo A. German Saul Burdman Y. Okon Jaime Kigel 《Biology and Fertility of Soils》2000,32(3):259-264
The effects of inoculation with Azospirillum brasilense Cd on root morphology and growth of common bean (Phaseolus vulgaris L.) were studied under different growth systems and water regimes. The root systems were evaluated by image analysis. In
a PVC-tube growth system, inoculation with A. brasilense at 107 colony forming units (CFU) ml–1 increased root length, root projection area, specific root length (m g–1) and specific root area (cm2 g–1), as compared with non-inoculated controls, resulting in root systems with longer and thinner roots. Water stress induced
similar root responses to those observed after inoculation with A. brasilense. No increase in plant biomass was observed in inoculated plants, suggesting that under the tested growth conditions, a relatively
larger amount of resources is required for the maintenance of the thinner roots. In water-stressed potted plants, the effect
of A. brasilense on tap root length was inoculum-concentration dependent. At 107 CFU ml–1 this effect was significant as compared to non-inoculated controls. In a pouch system without water stress, inoculation with
A. brasilense at a concentration of 105–107 CFU ml–1 2 days after germination resulted initially (2 days after inoculation) in an increase in root length (95%) and root fresh
weight (66%), but reduced root diameter (20%), compared to controls. At this early stage of growth the distribution of root
length among the different root diameter classes changed: the thinner-root classes had the largest proportion of longer roots.
Received: 3 January 2000 相似文献