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71.
Combined quantitative (real-time) polymerase chain reaction and immunohistochemistry were used to evaluate the expression of the minor acute phase protein alpha 1-acid glycoprotein (AGP, orosomucoid) in bovine extrahepatic tissues. AGP was produced mainly in the salivary glands and spleen, whereas minor expression was detected in all other tissues sampled, including lung, lymph nodes, uterus, ovary, kidney and tongue. The findings were consistent with immunohistochemical results. In view of the immunomodulatory and direct antibacterial activity of AGP, its expression in the salivary glands may signal an involvement in the regulation of the local immunity, even in non-pathological conditions.  相似文献   
72.
Dehydration, to varying degrees, will inevitably occur in horses participating in endurance trail rides. This water loss is directly related to the amount of body water lost through evaporative cooling, that in turn being related to the amount and rate of work performed, and to the environmental temperature and humidity.An electronic apparatus that can substitute for the conventional and time-consuming venous haematocrit was developed to measure the animals' hydration status. The mechanism of this electrometer is based upon the relationship between the red cell content and the electrical conductivity of the blood. The electrometer reading gave a significant correlation (p<0.001) with the venous haematocrit, thus indicating that the electrometer is a reliable apparatus for determining the animals' hydration status within seconds of venepuncture.  相似文献   
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Decreased calving performance not only directly impacts the economic efficiency of dairy cattle farming but also influences public concern for animal welfare. Previous studies have revealed a QTL on Bos taurus autosome (BTA) 18 that has a large effect on calving traits in Holstein cattle. In this study, fine mapping of this QTL was performed using imputed high‐density SNP chip (HD) genotypes followed by imputed next‐generation sequencing (NGS) variants. BTA18 was scanned for seven direct calving traits in 6113 bulls with imputed HD genotypes. SNP rs136283363 (BTA18: 57 548 213) was consistently the most significantly associated SNP across all seven traits [e.g. p‐value = 2.04 × 10?59 for birth index (BI)]. To finely map the QTL region and to explore pleiotropic effects, we studied NGS variants within the targeted region (BTA18: 57 321 450–57 625 355) for associations with direct calving traits and with three conformation traits. Significant variants were prioritized, and their biological relevance to the traits was interpreted. Considering their functional relationships with direct calving traits, SIGLEC12, CD33 and CEACAM18 were proposed as candidate genes. In addition, pleiotropic effects of this QTL region on direct calving traits and conformation traits were observed. However, the extent of linkage disequilibrium combined with the lack of complete annotation and potential errors in the Bos taurus genome assembly hampered our efforts to pinpoint the causal mutation.  相似文献   
75.
We report the results of a 6-year serological and virological monitoring performed in ducks and coots in Italy, in order to assess the degree of influenza A virus circulation in these birds during wintering. A total of 1039 sera collected from 1992 to 1998 was screened by a double antibody sandwich blocking ELISA (NP-ELISA): seroprevalence of antibodies to influenza A viruses was significantly higher in ducks compared to coots (52.2% vs. 7.1%, respectively). The hemagglutination-inhibition (HI) assay, performed on NP-ELISA positive sera, showed that 16.9% of these duck sera and 33.3% of these coot sera had antibodies to at least one influenza virus HA subtype: ducks showed HI antibodies against most of the HA subtypes, except for the H3, H4, H7, and H12; coots were seropositive to the H3 and H10 subtypes, only. From 1993 to 1998, 22 virus strains were obtained from 802 cloacal swabs, with an overall virus isolation frequency of 2.7%. Viruses belonging to the H1N1 subtype were by far the most commonly circulating strains (18/22) and were isolated mainly from ducks (17/18). The remaining viruses were representative of the H10N8, H5N2 and H3N8 subtypes. Our data indicate some differences between influenza A virus circulation in sympatric ducks and coots and a significant antigenic diversity between some reference strains and viruses recently isolated in Italy.  相似文献   
76.
Histomoniasis or blackhead is a disease of gallinaceous birds, caused by the protozoon Histomonas meleagridis. Since traditional diagnostics for the detection of this disease are complex and far less sensitive than molecular tools, a PCR would provide a more rapid and sensitive alternative. However, intestinal material and droppings, which are preferably used in epidemiological studies of histomoniasis, often contain PCR inhibitory substances. To detect these false negative results, the use of an internal amplification control is essential. Nevertheless, the recently developed PCR tests lack this internal control. Therefore, a new PCR assay with H. meleagridis specific primers was developed which does include an internal amplification control. The diagnostic value of the PCR assay was evaluated in comparison to three other conventional H. meleagridis specific PCR tests (HIS5, HM1 and HM2). None of the organ samples originating from uninfected turkeys, showed positive PCR results in any of the tests. Among the lesion-positive, inhibition-free samples, 95.4% were positive by our PCR assay, while only 50, 66.7 and 83.3% of the lesion-positive organs tested positive by the HM1, the HIS5 and the HM2 PCR respectively. In conclusion, our PCR offers the use of the internal control to detect false negative results and an increased sensitivity, and thus should be useful for routine diagnosis of H. meleagridis in poultry.  相似文献   
77.
Viruses have evolved different strategies to interfere with apoptotic pathways in order to halt cellular responses to infection. One previous study showed that transient transfection of bovine herpesvirus type-1 (BHV-1) UL14 protein is efficient in protecting Madin Darby kidney (MDBK) and human chronic myelogenous leukemia (K562) cells from sorbitol-induced apoptosis. This protein corresponds to a putative protein of BHV-1, which shares aminoacid sequence with a part of the peptide-binding domain conserved in human heat shock protein (HSP70) family. The pBK-CMV-UL14 plasmid transfected MDBK cells treated with sorbitol did not show caspase-3 and caspase-9 activation with respect to non-transfected MDBK cells (UL14 negative). Furthermore, we report that the expression of the full length sequence of BHV-1 UL14 is evident after 7 h of infection of BHV-1 on MDBK cells which were then treated with sorbitol. These results indicate that UL14 gene product has important implications to enhance cell survival in response to apoptotic stimuli.  相似文献   
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A total of 595 faecal samples from raptorial birds, either captive or free‐living, residing in GREFA Wildlife Hospital were bacteriologically examined using various selective media and an Automated Diagnostic Assay System for Salmonella detection. Serotype and phage type of the strains identified as Salmonella was determined. In the captive group, of the 285 samples examined, 21 (7.36%) were positive for Salmonella. Serotyping revealed that most of the individuals were infected by Salmonella serotype Havana. This result suggested that there could be a source of contamination in the Hospital although it could not be established. In the wild free‐living group, over 310 samples examined (4.19%) were positive for Salmonella. The Salmonella isolates showed a major variety of serotypes: Enteritidis, Adelaide, Brandenburg, Newport, Typhimurium, Hadar, Saintpaul and Virchow. Most of them are similar to those commonly described in isolates from human and domestic animals. These results indicate that wild birds could be involved in the dissemination of Salmonella in humans or domestic animals or vice versa.  相似文献   
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