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961.
The aim of the study was to evaluate the occurrence of mycotic and protohecal mastitis in herds in south-eastern part of Poland. A total of 3091 milk samples from udder quarters with clinical and subclinical mastitis from 29 dairy herds was investigated in this survey. Milk samples were plated as soon as possible on blood agar (BA), Mac Conkey agar, aesculin-tallium acetate-crystal violet agar, and Sabouraud agar. A hundred and thirty one yeast (4.23%) and eleven Protoheca zopfii (0.35%) strains were isolated from cows with clinical and subclinical mastitis. All the isolated fungi were the yeast classified into 4 genera (Candida, Trichosporon, Saccharomyces and Rhodotorula). The most frequently isolated yeasts were Candida sp., C. kefyr, C. humicola, C. rugosa and C. inconspicua. Both fungi and algae were isolated first of all during a confinement-housing season.  相似文献   
962.
OBJECTIVE: To compare gravimetric and colorimetric methods of quantifying surgical blood loss, and to determine if there is a correlation between preoperative hemostatic tests (buccal mucosa bleeding time [BMBT] and intraoperative blood loss). STUDY DESIGN: Prospective clinical study. ANIMALS: Dogs (n=15) admitted for cutaneous tumor excision, orthopedic procedure, or exploratory laparotomy. METHODS: Intraoperative blood loss was quantified by measuring irrigation fluid and weighing surgical sponges used for blood and fluid collection during surgery. Results of gravimetric measurements were then correlated to blood loss quantified using spectrophotometric analysis of hemoglobin (Hb) content. Hemostatic variables including BMBT were measured before surgery and compared with the calculated amount of blood loss. RESULTS: Blood loss quantified by gravimetric measurement showed a significant correlation with colorimetric determination of Hb content in surgical sponges and collected irrigation fluid (r=0.93, P<.0001). BMBT correlated weakly but significantly with intraoperative blood loss (r=0.56, P<.05). CONCLUSIONS: Quantifying intraoperative blood loss using spectrophotometric Hb analysis accurately assessed the amount of blood loss; however, it is a time-consuming procedure, primarily applicable as a research tool. Gravimetric evaluation of intraoperative blood loss was found to be an accurate method, which can be recommended for use in a clinical setting. CLINICAL RELEVANCE: Estimation of blood loss using a gravimetric method is accurate and applicable in the clinical setting and provides surgeons with a simple and objective tool to evaluate intraoperative blood loss.  相似文献   
963.
The inter- and intra-species differences in the response to lipopolysaccharides (LPS) are well recognised in mammalian species. It has been hypothesized that these differences can be attributed to genetic polymorphisms in the components involved in LPS signal transduction. These components include the cluster of differentiation factor 14 (CD-14), a membrane bound protein on the surface of mononuclear cells that recognises LPS and a receptor complex consisting of Toll-like receptor-4 (TLR-4) and myeloid differentiation factor-2 (MD-2). Sequencing of these three proteins in humans and mice revealed that all three are susceptible to polymorphic alterations, influencing the response to LPS. Previous experiments in the horse showed large inter-individual variations in the response to LPS. With the aim to assess this inter-individual variation, we performed a whole blood assay in 10 healthy horses as a functional assay to study the responsiveness to LPS. In 3 out of the 10 horses, LPS-induced TNF-alpha production was significantly lower compared to the overall mean. Subsequently the entire cDNA sequence encoding for the TLR-4, MD-2 and CD-14 protein was documented for each horse. Although mutations were observed in the sequence of TLR-4, these could not be related to an altered response to LPS in the concentration used in this study, as determined in the whole blood assay. Despite the various mutations found in the TLR-4 receptor protein, no alterations could be found in either the MD-2 or CD-14 gene, which are obviously more conserved structures.  相似文献   
964.
965.
蚕品种选育多用途化发展趋势   总被引:4,自引:0,他引:4  
为了满足蚕桑生产发展多元化和提升改造传统蚕桑业发展需要开展的特殊用途蚕品种选育进展迅速,本文就以蚕丝生产为目的如雄蚕品种、细纤度蚕品种、粗纤度蚕品种、人工饲料育品种及广食性蚕品种、天然彩色茧蚕品种等的选育,以及非蚕丝生产为目的如吐平面丝蚕品种、吐丝胶茧蚕品种、生物反应器专用蚕品种、药食专用蚕品种等育种研究进展进行概述.  相似文献   
966.
The pathology of African bovine trypanosomosis was compared in Zebu cattle subcutaneously inoculated with three clones of trypanosomes corresponding to the three genetically distinct types of Trypanosoma congolense; savannah-type, west African riverine/forest-type and kilifi-type. All inoculated animals became parasitaemic between 7 and 11 days post-infection (dpi). The savannah-type showed consistently higher levels of parasitaemia and lower packed red cell volume percentages and leukocyte counts than the other two types. The syndrome was also more severe in the savannah-type and led inexorably to death between 29 and 54 dpi while animals with the forest or the kilifi-types recovered from earlier symptoms and haematological alterations after 3 months of infection. By the end of the experiment, the animals self-cured from the forest-type infection and the kilifi-type passed under control. The results of the present study indicated clear difference in pathogenicity between the three types of T. congolense; the savannah-type was virulent while the forest-type was of low pathogenicity and the kilifi-type was non-pathogenic.  相似文献   
967.
The graft-versus-host reaction (GVHR) was demonstrated in a salmonid model system of clonal diploid and triploid amago salmon. Triploid operculum grafts on clonal diploid evoked an acute rejection within 12 days. Grafts exchanged among triploid amago salmon exhibited prolonged survival for 18 days. In contrast, diploid grafts on triploid, and allografts among clonal diploid amago salmon were accepted. A typical GVHR was induced in triploid recipients by intraperitonal injection of head kidney cells from sensitised diploid donors. The clinical signs of graft-versus-host disease (GVHD) were observed in the recipients after 1 week of cell injection as a loss of appetite and appearance of solid faeces, followed by haemorrhage, local swelling of ventral skin and an enlarged spleen. Three of six fish died within 1 month. Water temperature and frequency of sensitisation are critical to induce GVHR. Diploid donors had to be sensitised three times at 20 degrees C to induce the typical GVHR. GVHR was most effectively induced by head kidney cells, followed by peripheral blood leucocytes (PBL) and spleen cells. Ploidy analysis by flow cytometry revealed that the donor head kidney cells greatly increased in the recipient liver, head kidney and spleen, and reached the peak after 9 days of donor cell injection. The results in the present study are quite similar to the findings in ginbuna and ginbuna-gold fish hybrid system, suggesting the presence of T cells in salmonid as well as cyprinid fish.  相似文献   
968.
969.
Enteral nutrition coupled with bacterial colonization has been shown to have major functional and developmental effects during the postnatal period of neonates. In this study, we developed a highly sensitive premature pig model to elucidate the specific developmental impact of initial bacterial colonization on premature neonates by comparing germ-free and conventionally reared pigs. Thirty-eight preterm pigs (93% gestation) were delivered via caesarean section and reared in either germ-free or conventional isolators for 40–48 h. Pigs were fed either infant milk formula or sow's colostrum. Enteral feeding for two days had trophic effects on gastrointestinal weights, particularly for pancreas, stomach and small intestine (SI). The absence of bacteria in formula fed pigs resulted in a mucosa that appeared more robust and had higher weights for both SI and pancreas, compared to conventional formula fed pigs (P < 0.05). Colostrum fed pigs also had markedly increased mucosal SI proportions, lung and spleen weights compared to conventional formula fed pigs. Colostrum fed pigs and germ-free pigs were similar although stomach, pancreas and distal SI weights were highest for germ-free pigs. The results demonstrate that the initial bacterial colonization interacts with diet to modulate the early neonatal organ development, particularly of the GIT.  相似文献   
970.
The objective of this study was to characterize a group of small dairy producers in the central coast of Peru and determine the most important limiting factors that affect animal productivity, using Participatory Rural Appraisal methodologies. The information collected during a year included biological and socio-economic characteristics. Inappropriate nutrition, management, health and reproduction were observed in most farms. The average number of animals per family was 17.3, of which 40% were bulls and growing calves. Milk production and net cash income were reduced in the summer. The feeding programme for lactating and growing females of forage exchanged for labour and purchased concentrates did not theoretically or practically meet the cows’ needs. All water was carried to the site on donkeys from one kilometre distance. All cows were negative for a number of potential infectious diseases. By California Mastitis Test of routine samples 7.1% of cows had clinical mastitis and 66.1% subclinical. Taking notional labour and forage costs into account, milk production was at a loss but the farmers considered neither and were satisfied with a net cash income from milk sales three times the average agricultural wage.  相似文献   
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