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Flow cytometric sorting technology was used to measure the difference in DNA content between X- and Y-chromosome-bearing spermatozoa in bucks. Spermatozoa were analysed by flow cytometry to characterize X- and Y-chromosome-bearing sperm populations and to quantify the DNA difference between them. Two symmetrical, overlapping and clearly separated peaks, corresponding to X- and Y-bearing spermatozoa, were detected. The difference in fluorescence intensity between the peaks was 4.4 +/- 0.03% without any significant inter- or intra-animal variations. Therefore, the identification and selection of high-purity samples of sperm populations for sex sorting is easier in bucks compared with other domestic species.  相似文献   
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The original article to which this Correction refers was published in Pest Management Science 58 (7): 649–662 (2002).Copyright © 2004 Society of Chemical Industry  相似文献   
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The purpose of this article is to provide a review of the current knowledge and opinions about the epidemiology, clinical findings (including sequelae), diagnosis, treatment and monitoring of equine pituitary pars intermedia dysfunction, particularly in the Australian context. This information and the recommendations provided will assist practitioners in making informed decisions regarding the diagnosis and management of this disorder.  相似文献   
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The purpose of this study was to investigate the effect of seminal plasma (SP) from bulls of known fertility on bovine endometrial epithelial cells (bEEC) in culture. The bEEC from passage 5, approximately 5.0–13 × 105 cells per flask, were challenged with SP from bulls of high or low fertility (n = 3 and 2, respectively) or PBS (control), at 1% (75 μl) or 4% (300 μl) and were incubated for 72 hr (n = 13 per challenge). Total cell number and viability of bEEC after challenge with 1% SP from either high‐ or low‐fertility bulls (75H or 75L, respectively) did not differ from controls. In contrast, challenge with 4% of SP from high‐ or low‐fertility bulls (300H or 300L) negatively affected bEEC cell number and viability. Challenge with 300 L had a greater adverse effect than 300H. These results suggest that the negative effect of bovine SP on bEEC is both dose‐dependent and fertility‐dependent.  相似文献   
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Numerous culture-based diagnostics are available on the Australian and international markets for on-farm detection of bacterial pathogens in milk. Use of such diagnostics may provide an opportunity to improve the prudent use of antimicrobials in udder health management. Farms are low-resource settings in terms of diagnostic microbiology capacity. The World Health Organisation has identified criteria for the evaluation of diagnostic tests in low resource settings based on Accuracy, Sensitivity, Specificity, User-friendliness, being Rapid or Robust, Equipment-free and being Deliverable (ASSURED). Here, we review how those criteria can be interpreted in the context of microbiological diagnosis of mastitis pathogens, and how on-farm diagnostics that are currently available in Australia perform relative to ASSURED criteria. This evaluation identifies multiple trade-offs, both with regard to scientific criteria and with regards to convenience criteria. More importantly, the purpose of testing may differ between farms, and test performance should be evaluated relative to its intended use. The ability of on-farm mastitis diagnostics to inform mastitis treatment decision-making in a timely and cost-effective manner depends not just on test characteristics but also on farm-specific pathogen prevalence, and on the farm enterprise's priorities and the farm manager's potential courses of action. With most assay evaluations to date conducted in professional laboratories, there is a surprising dearth of information on how well any of the diagnostic tests perform on-farm and, indeed, of the on-farm decision-making processes that they aim to inform.  相似文献   
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In an experiment with pure-culture sclerotia of Sclerotium cepivorum and Stromatinia gladioli a large proportion of the sclerotia survived burial for 20 years in the field in the absence of host plants. Some evidence for metabolic activity or leakage leading to the gradual erosion of the sclerotial contents was obtained with S. cepivorum . The results of other experiments suggested that, for unknown reasons, a variable proportion of sclerotia formed naturally on infected plants may decay shortly after their formation, but those which survive beyond this limited period are likely to remain viable for many years. The viability of sclerotia was also reduced by prolonged flooding, but the period for which land would have to be under water excludes this as a method of eliminating sclerotia from infested land in the UK. Treatment with the mycoparasite Teratosperma oligocladum did not affect the survival or infectivity of sclerotia of S. cepivorum or S. gladioli .  相似文献   
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In an investigation conducted over 5 years, tests of samples from the Scottish Seed Potato Classification Scheme showed that when monoclonal antibodies (McABs) were used with the enzyme-linked immunosorbent assay (ELISA), they reliably detected the tobacco veinal necrosis strain of potato virus Y (PVYN). Polyclonal antibodies used in the first 3 years of the investigation were unreliable in differentiating PVYN from the ordinary strain (PVYN). It is suggested that ELISA and McABs be routinely used to diagnose PVYN and that all samples which give negative results be further assayed biologically to identify the virus or to indicate strains of PVYN not detectable by the McAB. Problems encountered with both assay systems are discussed.  相似文献   
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