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miRNAs are small non‐coding regulatory RNAs that play key roles in diverse biological processes. In this study, we used the Solexa sequencing technique to profile miRNAs in breeder cock testes to illustrate their functions. A total of 663 co‐expressed miRNAs and 3,180 co‐expressed piRNAs were detected in three libraries. Based on Mir‐X? miRNA qRT‐PCR, three miRNAs representing low, medium and high expression levels according to the sequencing results were selected randomly to validate the miRNAs' expression profiles. Results suggested that the miRNA expression profiles data could represent actual miRNA expression levels. Moreover, target genes prediction of the co‐expressed miRNAs and further Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were performed, which revealed that some candidate miRNAs were involved in the regulation of the spermatogenesis process, spermatozoa function and testicular metabolism. In conclusion, we provided a useful resource for further elucidation of the miRNAs' regulatory role in spermatogenesis, contributing to a preliminary database for functional and molecular mechanistic studies in testicular metabolism, spermatogenesis and other testes functions.  相似文献   
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Salmonella in cattle herds may behave as epidemic or endemic infections. An intensive longitudinal sampling study across all management groups and ages on six dairy farms in the UK was used to examine patterns of Salmonella shedding, following the prior identification of either Salmonella Dublin (SD) (three farms) or Salmonella Typhimurium (ST) (three farms) on the premises in the context of clinical salmonellosis. Individual faeces, pooled faeces and environmental samples (total 5711 samples), taken approximately every six weeks for 15-24 weeks, were cultured for Salmonella. SD was detected at low frequency (on any visit, 0.5-18.3 per cent of samples positive) and most consistently in calves. By contrast, ST was isolated at higher frequency (on any visit, 6.8-75 per cent of samples positive), and in higher numbers, up to 10(7) cfu/g faeces. Significantly more samples from calves were positive for ST than were positive for SD (50.6 per cent v 3.1 per cent; P?相似文献   
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REASONS FOR PERFORMING STUDY: A detailed review of laboratory records for equine abortion is fundamental in establishing current disease trends and suggesting problems important for further research. OBJECTIVES: To review the causes of abortion and neonatal death in equine diagnostic submissions to the Animal Health Trust over a 10 year period. METHODS: The diagnoses in 1252 equine fetuses and neonatal foals were reviewed and analysed into categories. RESULTS: Problems associated with the umbilical cord, comprising umbilical cord torsion and the long cord/cervical pole ischaemia disorder, were the most common diagnoses (38.8%: 35.7% umbilical cord torsion and 3.1% long cord/cervical pole ischaemia disorder). Other noninfective causes of abortion or neonatal death included twinning (6.0%), intrapartum stillbirth (13.7%) and placentitis, associated with infection (9.8%). E. coli and Streptococcus zooepidemicus were the most common bacteria isolated. Neonatal infections not associated with placentitis accounted for 3.2% of incidents; and infections with EHV-1 or EHV-4 for 6.5%. CONCLUSIONS: Definitive diagnosis of equine abortion is possible in the majority of cases where the whole fetus and placenta are submitted for examination. Potential relevance: Given the high incidence of umbilical cord torsion and related problems as causes of abortion in UK broodmares, more research on factors determining umbilical cord length and risk of torsion is essential.  相似文献   
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