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971.
972.
对鸡舍进行良好的消毒,可使每批鸡获得较安全的条件,提高育成率。“禽防二号”按5g/m3用量密闭熏烟消毒12h以上,对鸡细菌病、病毒病病原体均有强烈的杀灭效果。消毒效果不受温湿度影响,消毒后不留残毒,对鸡生长发育及产蛋无不良影响,是一种广谱、高效、使用方便、价格低廉的理想消毒药剂。 相似文献
973.
974.
四种草蛉生活史和习性的研究 总被引:9,自引:2,他引:7
在室内饲养了四种草蛉,观察其生活史和各发育阶段的历期。结合田间消长调查,认为四种草蛉在山东一年主要发生四代,成虫寿命和产卵期长,世代重叠现象严重,且系兼性滞育越冬,部分个体发育至四代以上。对草蛉食棉蚜及棉铃虫卵量作了观察。叶色草蛉是山东麦田、棉田的优势种,其次是中华草蛉。在棉田内自然蛉量以7月中旬至8月上旬最多,应注意保护和繁殖释放,以增加棉田蛉量;这是减轻和防治伏蚜和三代棉铃虫为害的重要措施之一。草蛉是棉蚜、棉铃虫的重要天敌。叶色草蛉(Chrysopa phyllochromaWesmacl)、中华草蛉(C.sinica Tjeder)、大草蛉(C.SeptempunctataWesmael)和丽草蛉(C.formosa Brauer)是我省的主要种类。1976—1978年于临清、泰安等县对其生活史和田间发生情况等作了观察,现整理如下。 相似文献
975.
大白菜传统育种方法受到资源数量所限,品种选育难度持续增大,四倍体大白菜因基因型丰富、剂量高、抗性强、资源范围广,利于新优品种选育.河北省农林科学院经济作物研究所(原蔬菜花卉研究所)以四倍体材料新413为父本,翠绿5-3-2-2-1为母本进行杂交,培育出抗病、优质的四倍体大白菜杂交一代新品种"多维462".生长期70~75d,株型中等,竖心,株高45cm,叶球重3kg.一般亩产6000kg,净菜率80%,适口性好、品质极佳.高抗病毒病、软腐病、霜霉病,抗逆性强,全国各地均可栽培.适合作为礼品菜、特菜、超市用菜,是无公害蔬菜、出口商品菜和中国北方秋早熟大白菜种植的理想品种. 相似文献
976.
López Peña M Muñoz F Alemañ N González A Pereira JL Nieto JM 《Veterinary pathology》2005,42(4):489-491
A 6-month-old female German Shepherd Dog died as a result of profuse oral bleeding. At postmortem examination, the oral cavity showed visible roots of the right mandibular fourth premolar and first molar teeth and, in addition, they were very mobile and compressible. Radiographs showed a generalized radiolucency in the body of the right mandible, with evidence of resorption of the affected alveolar bone. Histologically, the lesion of the right mandible was characterized by the lysis of bony structures and a non-malignant proliferation of blood-filled vascular spaces lined by a single layer of well-differentiated endothelial cells. The clinical, radiographic, and histologic presentation of this dog is consistent with that associated with Gorham-Stout disease, a rare bone disorder in humans. 相似文献
977.
With the aim of achieve a better understanding of the epidemiology and distribution of bovine leukaemia virus (BLV) infection in Chile, we assessed the suitability of using DNA isolated from the leukocyte fraction of bulk milk samples to carry out PCR-RFLP and DNA sequence analysis. The env fragment of BLV was successfully amplified from 33 serologically positive bulk milk samples collected from different geographical areas in the south of Chile. Restriction analysis allowed to classify 17 isolates within the Australian subgroup and 16 within the Belgium subgroup. DNA sequence and multiple alignment analysis of eight Chilean isolates showed a significantly higher frequency of single and double nucleotide substitutions. Most of these mutations were non-silent, resulting in changes at the protein level in several important epitopes of gp51. The Chilean sequences and 59 BLV env sequences available at GenBank, were subjected to a phylogenetic analysis, resulting in four different clusters. The groups identified were not related to those previously defined by restriction analysis. Chilean isolates were included in two different clusters and were genetically not related to isolates collected from neighbouring countries. Considering our results we can conclude: (i) bulk milk samples are suitable to identify the presence of BLV allowing epidemiological and genetic studies to be conducted on large geographical areas; (ii) at least four different genetic groups of BLV were identified by phylogenetic analysis, with Chilean isolates included in two different sub clusters. 相似文献
978.
Castrillo C Baucells M Vicente F Muñoz F Andueza D 《Journal of animal physiology and animal nutrition》2005,89(3-6):194-198
Near-infrared reflectance spectroscopy (NIRS) was used to predict the chemical composition, apparent digestibility and digestible nutrients and energy content of commercial extruded compound foods for dogs. Fifty-six foods of known chemical composition and in vivo apparent digestibility were analysed overall and 51 foods were used to predict gross energy digestibility and digestible energy content. Modified partial least square calibration models were developed for organic matter (OM), crude protein (CP), ether extract (EE), crude fibre (CF), nitrogen free extracts (NFE) and gross energy (GE) content, the apparent digestibility (OMD, CPD, EED, NFED and GED) and the digestible nutrient and energy content (DOM, DCP, DEE, DNFE and DE) of foods. The calibration equations obtained were evaluated by the standard error and the determination coefficient of cross-validation. The cross-validation coefficients of determination (R) were 0.61, 0.99, 0.91, 0.96, 0.94 and 0.92 for OM, CP, EE, CF, NFE and GE, the corresponding standard error of cross-validation (SECV) being 5.80, 3.51, 13.35, 3.64 and 16.95 g/kg dry matter (DM) and 0.29 MJ/kg DM respectively. The prediction of apparent digestibility was slightly less accurate, but NIRS prediction of digestible nutrient (g/kg DM) and DE (MJ/kg DM) gave satisfactory results, with high R (0.93, 0.97, 0.93, 0.83 and 0.93 for DOM, DCP, DEE, DNFE and DE respectively) and relatively low SECV (11.55, 6.85, 12.14 and 22.98 g/kg DM and 0.47 MJ/kg DM). It is concluded that the precision of NIRS in predicting the energy value of compound extruded foods for dogs is similar or better than by proximate analysis, as well as being faster and more accurate. 相似文献
979.
Mainar-Jaime RC Muñoz PM de Miguel MJ Grilló MJ Marín CM Moriyón I Blasco JM 《The Canadian veterinary journal. La revue veterinaire canadienne》2005,46(10):913-916
When brucellosis false positive serological reactions happen in cattle, the serial use of pairs of specificity-correlated serological tests (rose bengal, complement fixation, competitive ELISA) results in specificities lower than expected. In this situation, highly specific tests, such as the indirect ELISA used alone, may be more adequate than serial testing. 相似文献
980.
Relationship between serum acute phase protein concentrations and lesions in finishing pigs 总被引:1,自引:0,他引:1
Pallarés FJ Martínez-Subiela S Seva J Ramis G Fuentes P Bernabé A Muñoz A Cerón JJ 《Veterinary journal (London, England : 1997)》2008,177(3):369-373
To establish the relationship between serum levels of three acute phase proteins, haptoglobin (Hp), C-reactive protein (CRP) and serum amyloid A (SAA), and the occurrence and severity of lesions at slaughter, a study was carried out using 70 fattening pigs from a finishing unit. Pigs were divided into three groups: Group 1 (25 pigs with clinical signs of disease), Group 2 (25 apparently healthy pigs with lesions at slaughter) and Group 3 (20 apparently healthy pigs with no lesions at slaughter). Serum levels of CRP, SAA and Hp were significantly higher in pigs with clinical signs of disease than in apparently healthy animals. Additionally, in apparently healthy pigs, serum levels of Hp and CRP were significantly higher in animals with lesions than those without lesions. The extent and severity of lung lesions were related to serum levels of Hp. 相似文献