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排序方式: 共有343条查询结果,搜索用时 15 毫秒
101.
Tania de Freitas Raso Angelo Berchieri Júnior Aramis Augusto Pinto 《Journal of zoo and wildlife medicine》2002,33(2):118-121
The prevalence of Chlamydophila psittaci (formerly Chlamydia psittaci) infection was assessed in 95 apparently healthy, captive Amazon parrots from three breeder collections in southeastern and west-central Brazil. Cloacal swabs from 95 birds were tested for chlamydial antigen, which was detected by direct immunofluorescence (DIF), and serum samples from 44 of these birds were tested for antibodies to C. psittaci using an enzyme-linked immunosorbent assay. The prevalences of active infection as detected by DIF were 16.7%, 22.2%, and 56.1%, and seroprevalences were 100%, 87.5%, and 60% in flocks A, B, and C, respectively. We can therefore infer that C. psittaci may be widespread in captive parrot populations in Brazil. 相似文献
102.
Ulcerative posthitis in bulls in Uruguay is described; 1096 bulls in 17 different establishments were examined. The incidence of bulls grazing on improved pasture was 32.9% in those under one year and 80.8% in animals of 18 to 36 months of age. Bulls grazing on natural pasture showed an incidence of 63.5% in adult animals irrespective of age. Histologic characteristics of the preputial lesions were acanthosis, parakeratosis and hyperkeratosis followed by invasion of leukocytes in the epithelium and ulceration. Corynebacterium renale was isolated from 59 of 204 prepuces. Based on the isolation of C. renale, histological lesions and the greater incidence in animals on high planes of nutrition, it is postulated that the lesion is due primarily to production of ammonia following the hydrolization of urea by the organism. 相似文献
103.
In the literature reviewed, there are certain differences of opinion with regard tostructural details of the wall of the internal carotid artery in the cervical and petrosalportion. Therefore, histological material of human necropsies was processed in order toobtain 10pm. paraffin sections of the artery and surrounding tissues which were stainedwith orcein, resordn-fuchsine, Verhoeff and picrofuchsine. While in the cervical segment of theartery there is a neat predominance of muscle fibres over elastic ones in the media, the elasticelements can be found especially in the inner layers of the adventitia, and there exist aclearly defined elastica interna and externa. Therefore the authors consider this part ofthe artery as of the transitional type. On the other hand, the petrosal portion must be consideredas of the muscular type, with abundant muscle fibres in the media and a wellformed and even double elastica interna, while the externa is scarcely visible. In bothsegments, the artery is very well fixed with the surrounding connective sheath. 相似文献
104.
105.
High levels of whole raw soybean in diets for Nellore bulls in feedlot: effect on growth performance,carcass traits and meat quality 下载免费PDF全文
N. R. B. Cônsolo R. Gardinal J. R. Gandra J. E. de Freitas Junior F. P. Rennó M. H. de A. Santana S. B. Pflanzer Junior A. S. C. Pereira 《Journal of animal physiology and animal nutrition》2015,99(2):201-209
The objective of this study was to evaluate the effect of whole raw soybean (WRS) in the finishing diet of Nellore cattle on productive performance, carcass traits, meat quality, fatty acid profile of meat, and blood parameters. In a completely randomized design, 52 Nellore bulls (mean body weight ± SD: 380 ± 34 kg) were allotted for 84 days. The animals received the following diets with a forage: concentrate ratio of 40/60: (i) WRS0: control diet without soybean grains; (ii) WRS8: diet containing 8% WRS in dry matter basis; (iii) WRS16: diet containing 16% WRS, and (iv) WRS24: diet containing 24% WRS. At intervals of 28 days, the animals were weighed, muscle and adipose tissue was analysed by ultrasound, and blood samples were collected. The animals were slaughtered on day 85 and liver weight and hot carcass weight were measured during slaughter. The pH and carcass dressing were calculated at 24 h after slaughter. Longissimus dorsi muscle samples were collected for the determination of fatty acid profile of meat, ether extract, tenderness and sensory analysis of meat aged for 14 days. Blood cholesterol content increased linearly with increasing proportion of whole raw soybean grains. The diet did not affect performance or carcass attributes. The WRS8 had the highest shear force values. In fatty acid profile, C14:0 decreased (p = 0.05), whereas 16:1, 20:0 and 20:1 fatty acids increased linearly with increasing proportion of WRS (p < 0.05). However, concentration of conjugated linoleic acid cis 9, trans 11 and 17:0 increased with WRS24 and WRS16. In the sensory analysis, WRS24 was more tender with respect to the other treatments (p < 0.05). Finally, the inclusion of WRS in the finishing diet of feedlot Nellore bulls only evidenced little changes in fatty acid profile and tenderness, in animals fed diets containing 16 or 24% soybean. 相似文献
106.
Alice Maria Melville Paiva Della Libera Fernando Nogueira de Souza Camila Freitas Batista Bruna Parapinski Santos Luis Fernando Fernandes de Azevedo Eduardo Milton Ramos Sanchez Soraia Araújo Diniz Marcos Xavier Silva Jo?o Paulo Haddad Maiara Garcia Blagitz 《Veterinary research》2015,46(1)
The effects of bovine leukemia virus (BLV) on the immune response have been extensively investigated; however, its effects on mammary gland immunity are only speculative. Although BLV has a tropism for B cells, it can affect both adaptive and innate immunities because these systems share many effector mechanisms. This scenario is the basis of this investigation of the effects of BLV on mammary gland immunity, which is largely dependent upon neutrophilic functions. Thus, the present study sought to examine neutrophilic functions and the lymphocyte profile in the milk of naturally BLV-infected cows. The viability of the milk neutrophils and the percentage of milk neutrophils that produced reactive oxygen species (ROS) or phagocytosed Staphylococcus aureus were similar between BLV-infected and BLV-uninfected dairy cows. Furthermore, the expression of CD62L and CD11b by the milk neutrophils and the percentage of milk neutrophils (CH138+ cells) that were obtained from the udder quarters of the BLV-infected cows were not altered. Conversely, the median fluorescence intensity (MFI) representing intracellular ROS production and the phagocytosis of S. aureus, the expression of CD44 by the milk neutrophils and the percentage of apoptotic B cells were lower in the milk cells from BLV-infected dairy cows, particularly those from animals with persistent lymphocytosis (PL). The lymphocyte subsets were not different among the groups, with the exception of the percentage of CD5−/CD11b− B cells, which was higher in the milk cells from BLV-infected cows, particularly those with PL. Thus, the present study provides novel insight into the implications of BLV infection for mammary gland immunity. 相似文献
107.
Duarte Ana Paula Melo Vander Freitas Brown George G. Pauletti Volnei 《Biology and Fertility of Soils》2014,50(5):851-860
Biology and Fertility of Soils - The survival and cast production of the tropical endogeic earthworm Pontoscolex corethrurus and the changes in chemical and physical characteristics induced by gut... 相似文献
108.
Mateus N Silva AM Vercauteren J de Freitas V 《Journal of agricultural and food chemistry》2001,49(10):4836-4840
Several anthocyanin-derived pigments that showed UV-visible spectra different from those of the original grape anthocyanins were detected by HPLC-DAD analysis in 1-year-old bottled Port wines from the Douro region. Among these, three malvidin 3-glucoside derived pigments were detected in large amounts, representing approximately 60% of the total anthocyanidin monoglucosides content. These pigments were isolated, purified, and identified by LSI-MS and NMR ((1)H, DQF-COSY, ROESY, HSQC, and HMBC) techniques. The major pigment is malvidin 3-glucoside pyruvic adduct, previously characterized, and the other two corresponded to its respective acetyl and coumaroyl glucoside derivatives. The latter is reported for the first time in red wines. 相似文献
109.
Modesto Lenon Romano de Almeida Anna Flávia Neri Steiner Daniel Ricardo Maass Ribeiro César Freitas Nodari Rubens Onofre Welter Leocir José da Silva Aparecido Lima 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(3):695-706
European Journal of Plant Pathology - Anthracnose (Elsinöe ampelina) is a major fungal disease in humid regions, causing damage to grapevine berries and decreasing fruit quality. Studies... 相似文献
110.
Rodrigo G. Freitas Pollyane S. Hermenegildo Renan S. Cascardo Lúcio M. S. Guimarães Samuel A. Santos Jorge L. Badel Poliane Alfenas-Zerbini Acelino C. Alfenas 《Plant pathology》2021,70(7):1708-1718
Bacterial wilt caused by Ralstonia solanacearum is a serious disease of eucalypt in humid and high temperature areas worldwide. Spreading of the bacterium in the field or to other nurseries occurs mainly by symptomless infected plant material. The use of pathogen-free propagating material as well as planting of resistant genotypes are currently the only strategies used for disease control. Therefore, a reliable and sensitive method for detection of low titres of R. solanacearum in infected plant tissue is essential for the success of management programmes. In this work, we adapted an efficient intercalating dye-based real-time PCR protocol to detect the bacterium in symptomless eucalypt plants as well as to investigate its movement in eucalypt clones CLR172 and CLR371, which exhibit resistant and susceptible phenotypes, respectively. We found that the bacterium translocates acropetally and basipetally in inoculated but symptomless cuttings of the resistant clone, as in cuttings of the susceptible clone displaying symptoms. Nevertheless, a smaller concentration of bacterial DNA was detected in tissues of the resistant clone. Mature biofilms occluding the xylem vessels were present in the susceptible clone whereas only single cells or small aggregates were observed in the resistant clone. This work contributes to improve our knowledge of the colonization process of R. solanacearum in eucalypt clones with different levels of susceptibility and to understand how the defence mechanisms against bacterial wilt in Eucalyptus work. Our findings could aid in the selection of the most resistant eucalypt clones to be used in wilt disease management programmes. 相似文献