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51.
AIM: To compare the bacteriological and clinical cure rates for clinical and subclinical mastitis in New Zealand dairy cows following treatment with either an intramammary penicillin-dihydrosptreptomycin preparation or a subcutaneous injection of penethamate hydriodide. METHODS: Milk samples were collected from clinical and subclinical cases of mastitis before and 14 and 21 days after initiation of treatment for bacteriological culture, somatic cell count determination and conductivity testing. RESULTS: No significant differences in the bacteriological cure rate of major Gram-positive pathogens, clinical cure rate, somatic cell count or conductivity were found between treatments. However, the bacteriological cure rate of coagulase-negative staphylococcus infections and the overall bacteriological cure rate was lower for quarters treated with penethamate than with penicillin-dihydrosptreptomycin. CONCLUSIONS: The bacteriological cure rate of mastitis caused by major Gram-positive pathogens, the clinical cure rate, somatic cell count and conductivity did not differ between the two antibiotic treatments. .  相似文献   
52.
将一种蛋白质在亚细胞中定位对于彻底了解其在细胞中的作用很重要。常规用于蛋白质定位的方法包括免疫荧光或免疫金电镜,以及将细胞组分进行免疫印演的方法。这二种方法,都必须利用所研究蛋白的特异抗体。然而,特异抗体的产生存在很多问题,并在许多情况下是定位过程的限速步骤,分离到一个新的CDNA克隆时,通常的做法是进行基因工程操作并做为细菌融合蛋自进行表达,这既耗时又有一定的困难,因为一些蛋白质在大肠杆菌中或是不稳定,或是表达量很低。另一种途径是利用推导的氨基酸顺序来人工合成多肽,再用此多肽来产生特异抗体。此法…  相似文献   
53.
在廉价的双层金属网中包入细刨花,可以用做饲养场鸡舍的挂帘,并可以通过塑料管上的小孔不断地吸收水分。在印度的北部,每年4~6月份为高温季节,而7~8月份是高温高湿期。4~6月份气温在38°—47℃范围间变化。而夜间的温度在30℃以上。  相似文献   
54.
The aim of this study was to examine the blood coagulation profiles of ferrets and compare them with those of rats. The ferret activated partial thromboplastin time (aPTT) was slightly longer than the rat aPTT. In contrast, the ferret prothrombin time and thrombin time were profoundly shorter than the corresponding rat values. The fibrinogen level in ferret plasma was 2 times higher than that in rats. Heparin prolonged all blood coagulation times in a concentration-dependent manner in both ferret and rat plasma. A significantly (P<0.01) higher concentration of heparin was required to double the aPTT in ferrets than rats. These blood coagulation data for ferrets will be useful in experimental animal studies.  相似文献   
55.
In Iberia there are 51 officially recognized cattle breeds of which 15 are found in Portugal and 38 in Spain. We present here a comprehensive analysis of the genetic diversity and structure of Iberian cattle. Forty of these breeds were genotyped with 19 highly polymorphic microsatellite markers. Asturiana de los Valles displayed the greatest allelic diversity and Mallorquina the least. Unbiased heterozygosity values ranged from 0.596 to 0.787. The network based on Reynolds distances was star-shaped with few pairs of interrelated breeds and a clear cluster of 4 breeds (Alistana/Arouquesa/Marinhoa/Mirandesa). The analysis of the genetic structure of Iberian cattle indicated that the most probable number of population clusters included in the study would be 36. Distance results were supported by the STRUCTURE software indicating a relatively recent origin or possible crossbreeding or both between pairs or small groups of breeds. Five clusters included 2 different breeds (Betizu/Pirenaica, Morucha/Avile?a, Parda de Monta?a/Bruna de los Pirineos, Barros?/Cachena, and Toro de Lidia/Brava de Lide), 3 breeds (Berrenda en Negro, Negra Andaluza, and Mertolenga) were divided in 2 independent clusters each, and 2 breeds were considered admixed (Asturiana de los Valles and Berrenda en Colorado). Individual assignation to breeds was not possible in the 2 admixed breeds and the pair Parda de Monta?a/Bruna de los Pirineos. The relationship between Iberian cattle reflects their geographical origin rather than their morphotypes. Exceptions to this geographic clustering are most probably a consequence of crossbreeding with foreign breeds. The relative genetic isolation within their geographical origin, the consequent genetic drift, the adaptation to specific environment and production systems, and the influence of African and European cattle have contributed to the current genetic status of Iberian cattle, which are grouped according to their geographical origin. The greater degree of admixture observed in some breeds should be taken into account before using molecular markers for genetic assignment of individuals to breeds.  相似文献   
56.
57.
ABSTRACT: Although the importance of wild ruminants as potential reservoirs of bluetongue virus (BTV) has been suggested, the role played by these species in the epidemiology of BT in Europe is still unclear. We carried out a serologic and virologic survey to assess the role of wild ruminants in the transmission and maintenance of BTV in Andalusia (southern Spain) between 2006 and 2010.A total of 473 out of 1339 (35.3%) wild ruminants analyzed showed antibodies against BTV by both ELISA and serum neutralization test (SNT). The presence of neutralizing antibodies to BTV-1 and BTV-4 were detected in the four species analyzed (red deer, roe deer, fallow deer and mouflon), while seropositivity against BTV-8 was found in red deer, fallow deer and mouflon but not in roe deer. Statistically significant differences were found among species, ages and sampling regions. BTV RNA was detected in twenty-one out of 1013 wild ruminants (2.1%) tested. BTV-1 and BTV-4 RNA were confirmed in red deer and mouflon by specific rRT-PCR.BTV-1 and BTV-4 seropositive and RNA positive wild ruminants, including juveniles and sub-adults, were detected years after the last outbreak was reported in livestock. In addition, between the 2008/2009 and the 2010/2011 hunting seasons, the seroprevalence against BTV-1, BTV-4 and BTV-8 increased in the majority of provinces, and these serotypes were detected in many areas where BTV outbreaks were not reported in domestic ruminants. The results indicate that wild ruminants seem to be implicated in the dissemination and persistence of BTV in Spain.  相似文献   
58.
The genetic similarity of Campylobacter jejuni isolates from pets, compared to human clinical cases and retail food isolates collected in Ireland over 2001-2006 was investigated by cluster analysis of pulsed-field gel electrophoresis (PFGE) fingerprinting profiles. Comparison of the PFGE profiles of 60 pet isolates and 109 human isolates revealed that seven (4.1%) profiles were grouped in clusters including at least one human and one pet C. jejuni isolate. In total six (1.6%) of 60 pet and 310 food profiles were in clusters with at least one food and one pet C. jejuni isolate. The detection of only a small number of genetically indistinguishable isolates by PFGE profile cluster analysis from pets and from humans with enteritis in this study suggests that pets are unlikely to be an important reservoir for human campylobacteriosis in Ireland. However, genetically indistinguishable isolates were detected and C. jejuni from pets may circulate and may contribute to clinical infections in humans. In addition, contaminated food fed to pets may be a potential source of Campylobacter infection in pets, which may subsequently pose a risk to humans.  相似文献   
59.
There is a global move from individual to group housing of gestating sows. In the European Union, individual gestating stalls will be banned by 2013. Just like in other industrialized regions, these stalls have been the standard housing system for intensively kept sows from the 1960s onward in the Flemish region of Belgium. Because the socioeconomic consequences for the pig industry may be far-reaching and because farmer attitude may influence the realization of the hoped-for improvement in animal welfare in practice, we conducted a survey from 2003 until 2009 among representative samples of Flemish pig producers every 2 yr. The share of farms with group housing increased from 10.5% in 2003 to 29.8% in 2007, but then dropped to 24.6% in 2009. It appears that after 2005 users of old group housing systems in particular stopped farming. Because sow herd size increased more on farms with vs. without group housing and because the proportion of the herd that was group-housed also tended to increase between 2003 to 2009, the change to group housing took place faster when expressed at the level of the sow (from 9.1% in 2003 to 34.1% in 2009) instead of farm. The percentage of farmers planning to convert to group housing within 2 yr was 4.1% in 2003, and 6 to 7% thereafter. These were typically young farmers (P = 0.006) with a large sow herd (P < 0.001) and with a likely successor (P = 0.03). Free access stalls were the most common group housing system (31% of farms, 37% of sows). Their popularity is expected to increase further at the expense of electronic feeding stations, ad libitum feeding, and stalls/troughs with manual feed delivery. User satisfaction was generally high but depended on whether or not all gestating sows were kept in group (P < 0.001), the provisioning of environmental enrichment (P = 0.057), and the age (P = 0.012) and type (P = 0.016) of system. The main criteria for choosing a certain group housing system were the investment costs and sow health and welfare. The importance of economic reasons (P = 0.007) and type of labor (P = 0.043) decreased with the age of the system. In 2003 and 2005 the main reason for not having converted to group housing was that farmers would stop keeping sows by 2013. In 2007 and 2009 the reasons mainly concerned uncertainty about the future and maximally delaying the conversion. Belgium is one of the European Union countries where the pig industry is expected to undergo drastic changes during the few years remaining before the ban on individual housing.  相似文献   
60.
The morphological features of the distal border synovial invaginations (SI) of the distal sesamoid bone (DSB) in horses were described by the use of computed tomography (CT). Transverse CT images were obtained on 50 cadaver forefeet from 25 Warmblood horses. Dorsal and sagittal planes were reformatted. The CT images allowed the evaluation of the number, shape, depth of penetration and direction of the SI into the bone. The total number of SI was 295 (mean 5.9). The number of invaginations in a particular DSB ranged from 3 (n = 3), 4 (n = 6), 5 (n = 11), 6 (n = 12), 7 (n = 13), 8 (n = 3), 9 (n = 1) to 11 (n = 1). The shape of the SI was 'conical' (n = 118), 'linear' (n = 109), 'lollipop' (n = 38) or 'branched' (n = 30). Penetration of the SI into the DSB was 'mild' in 195 cases, 'moderate' in 67 cases and 'deep' in 33 cases. The SI ran in a 'straight', 'dorsoproximal' and 'palmaroproximal' direction in 187, 28 and 80 cases, respectively. In only six DSBs, all SI ran in the same direction. The images obtained in this study may serve as reference for the radiographic evaluation of these SI.  相似文献   
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