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81.
Two vaccines, based on formalin-killed whole cells of toxigenic Pasteurella multocida type D and Bordetella bronchiseptica combined with a partially toxoided cell extract of P multocida, were prepared with Freund's incomplete adjuvant (vaccine 1) or by alum precipitation (vaccine 2). Each was tested for safety and efficacy in reducing the severity of nasal turbinate atrophy and improving the growth rate of pigs in three Western Australian commercial piggeries with endemic atrophic rhinitis. In safety experiments with vaccine 1, no adverse clinical effects were observed in vaccinated sows or their progeny. Piglets receiving vaccine 2 showed no injection site abnormalities, pyrexia or turbinate atrophy. In field trials, vaccine 1 significantly reduced the prevalence of moderate to severe nasal turbinate atrophy (Done score 3 to 5) when used in two piggeries (A and B). Progeny from vaccinated sows in piggery B also grew significantly faster than controls. When vaccine 2 was used in piggery A at a later date and in another piggery (C), growth rate was not improved in either piggery and the prevalence of moderate to severe turbinate atrophy was reduced only in piggery C.  相似文献   
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With the commercial release in Australia in 2004 of a vaccine against feline immunodeficiency virus (FIV; Fel‐O‐Vax FIV®), the landscape for FIV diagnostics shifted substantially. Point‐of‐care (PoC) antibody detection kits, which had been the mainstay for diagnosing FIV infection since the early 1990s, were no longer considered accurate to use in FIV‐vaccinated cats, because of the production of vaccine‐induced antibodies that were considered indistinguishable from those produced in natural FIV infections. Consequently, attention shifted to alternative diagnostic methods such as nucleic acid detection. However, over the past 5 years we have published a series of studies emphasising that FIV PoC test kits vary in their methodology, resulting in differing accuracy in FIV‐vaccinated cats. Importantly, we demonstrated that two commercially available FIV antibody test kits (Witness? and Anigen Rapid?) were able to accurately distinguish between FIV‐vaccinated and FIV‐infected cats, concluding that testing with either kit offers an alternative to PCR testing. This review summarises pertinent findings from our work published in a variety of peer‐reviewed research journals to inform veterinarians (particularly veterinarians in Australia, New Zealand and Japan, where the FIV vaccine is currently commercially available) about how the approach to the diagnosis of FIV infection has shifted. Included in this review is our work investigating the performance of three commercially available FIV PoC test kits in FIV‐vaccinated cats and our recommendations for the diagnosis of FIV infection; the effect of primary FIV vaccination (three FIV vaccines, 4 weeks apart) on PoC test kit performance; our recommendations regarding annual testing of FIV‐vaccinated cats to detect ‘vaccine breakthroughs’; and the potential off‐label use of saliva for the diagnosis of FIV infection using some FIV PoC test kits. We also investigated the accuracy of the same three brands of test kits for feline leukaemia virus (FeLV) diagnosis, using both blood and saliva as diagnostic specimens. Based on these results, we discuss our recommendations for confirmatory testing when veterinarians are presented with a positive FeLV PoC test kit result. Finally, we conclude with our results from the largest and most recent FIV and FeLV seroprevalence study conducted in Australia to date.  相似文献   
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A 13‐year‐old Romanov sheep presented for evaluation of vaginal discharge, depression and anorexia. Blood work demonstrated mature neutrophilia and marked hyperlactatemia. Transrectal and transabdominal ultrasound revealed echogenic fluid (pus) within the uterus. Purulent uterine fluid culture yield Escherichia coli. A diagnosis of pyometra was made. After medical treatment without clinical improvement, an exploratory laparotomy was performed, and a 360‐degree uterine left horn torsion was identified with the pyometra and multiple corpora lutea on both ovaries. Ovariohysterectomy was performed and the ewe recovered uneventfully.  相似文献   
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To clarify the early steps of symbiotic establishment, we studied the dynamics of Pinus pinaster (Ait.) Sol. tap root colonization and mycorrhiza formation by an IAA-overproducing mutant of the ectomycorrhizal fungus Hebeloma cylindrosporum Romagnesi and by the corresponding wild type strain. Differences between wild type and mutant strains were quantitative rather than qualitative and were detected two days after inoculation. Both fungal strains established a typical Hartig net when they colonized the tap roots. Consequently, colonized tap roots exhibited features of a true mycorrhiza and fungal colonization enhanced plant growth. Fungal colonization and Hartig net formation were more rapid with the mutant than with the wild type. Colonization, especially with the mutant strain, increased rhizogenesis and the production of mycorrhizas. The mutant formed a hypertrophic Hartig net in tap roots and mycorrhizal short roots and we obtained evidence that the process of short root transformation into mycorrhiza started before their emergence from the tap root. Hyphae of the Hartig net in the tap root penetrated the cortex of young lateral roots at the beginning of their elongation, after the endodermis layer broke under the pressure of the elongating lateral root. Colonization was inhibited when triiodobenzoic acid was added to the culture medium, providing circumstantial evidence that auxin is involved in mycorrhiza formation.  相似文献   
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As the demand for food-supply veterinarians changes, while the level of expertise necessary in this field markedly increases, there is a need to examine alternative modalities for delivering food-supply veterinary education. It seems clear that not all veterinary schools in the United States can sustain optimally sized facilities for the broad-based training in all species of food animals that the current and future food-supply veterinarian needs. An alternative model is for select schools to establish consortial centers of excellence in specific food-animal species, to which students from other schools can go for optimum final-year education. This alternative mode of food supply-veterinary medical education is discussed here.  相似文献   
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