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81.
A commercial inactivated iron restricted Salmonella Typhimurium and Salmonella Enteritidis vaccine was used to vaccinate chicks at 1 day and again at 4 weeks of age, with challenge by a high and a low dose of S. Typhimurium given either orally or by contact with seeder birds inoculated orally with a high dose of S. Typhimurium. In all three challenge regimes, the shedding of challenge strain was reduced significantly (p < 0.05) in vaccinated birds compared with unvaccinated controls. Vaccination reduced colonisation of internal organs after challenge by contact seeder birds. However, no effect of vaccination upon colonisation of internal organs after either high or low oral challenge was apparent. In conclusion, the data indicate that the vaccine should be a useful tool in the control of S. Typhimurium infection in chickens.  相似文献   
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A seven-year-old neutered/male Siberian Husky-cross dog was referred for evaluation of a gingival mass. Two years previously, the referring veterinarian had resected an ossifying epulis from the same area between the maxillary left first and second premolars. The neoplasm recurred 4-months after the original surgery. En bloc resection provided tumor-free margins. An oral examination 12-months following surgery indicated no gross signs of recurrence.  相似文献   
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Dothistroma needle blight (DNB) is a serious disease of the Pinaceae, mainly Pinus species, caused by the fungi Dothistroma septosporum and D. pini. Both species are regarded as invasive forest pathogens worldwide, with rising incidence in central and northern Europe over the last three decades. In this work, 29 sites were investigated between 2013 and 2015 in south-western Turkey. Morphological examination of needles confirmed DNB infection (i.e., Dothistroma conidiospores observed) at 18 sites, and a total of 108 Dothistroma sp. isolates were obtained from 11 of the sites. Host age seemed to be an important factor in both occurrence and severity of DNB in Pinus brutia forests. Continuous rainy days, especially in December, may increase severity of disease; however, extreme rain events may reduce available conidiospores on plant tissues or in the air. Species-specific mating type primers showed that all isolates were D. septosporum; D. pini was not detected. The mating type ratio was close to 1:1, indicating sexual recombination was occurring. Eleven microsatellite markers revealed 59 unique multilocus haplotypes (MLHs) among the 73 isolates originating from different conidiomata. The majority of MLHs were represented by a single isolate (n = 52) and only one MLH was shared between two localities. Analyses showed high genetic diversity, isolation-by-distance, and clear population clusters. These findings suggest that D. septosporum is well established in south-western Turkey and is probably not a recent introduction.  相似文献   
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Calpastatin activity measured at 24 h postmortem in bovine longissimus muscle (PMLD24) is correlated with Warner-Bratzler shear force (WBS) measurements, an objective measure of tenderness. A live-animal measurement of calpastatin activity that correlates with 24-h postmortem activity would provide information for selection programs without the expense of progeny testing. The purpose of this study was to evaluate the effectiveness of calpastatin activity measurements obtained on tissue samples from live animals and to determine the relationship among various calpastatin activity measures and tenderness determined by WBS and sensory panel. Biopsies (approximately 10 g) were obtained surgically 2 d before slaughter from the supraspinatus muscle on the anterior surface of the scapula (LISH0) from contemporary purebred Angus bulls (n = 12) and steers (n = 17). Biopsies from a subset of these cattle (n = 12) were refrigerated at 4 degrees C to simulate the postmortem cooling process for 24 h (LISH24) prior to extraction. A rib section anterior to the 12 and 13th rib interface was collected from all animals at the commercial abattoir between 22 and 23 h postmortem for PMLD24, sensory panel, and WBS measurements. A postmortem shoulder muscle sample (PMSH24) was collected at the same time. Calpastatin was extracted from all muscle samples using a heated calpastatin activity protocol. Sensory panel tenderness, WBS, LISH0, LISH24, and PMSH24 were not different between bulls and steers. However, PMLD24 values were significantly different. Significant partial correlations were found between WBS and sensory panel tenderness (-.55), between WBS and PMLD24 (-.43), and between LISH24 and PMLD24 (.78). Therefore, similar calpastatin activity values are possible with ante- and postmortem tissue samples, suggesting the possibility of using measurements from live-tissue biopsies from other than the longissimus muscle to predict end product tenderness.  相似文献   
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The fastidious, anaerobic spirochaete Brachyspira is capable of causing enteric disease in avian, porcine and human hosts, amongst others, with a potential for zoonotic transmission. Avian intestinal spirochaetosis (AIS), the resulting disease from colonisation of the caeca and colon of poultry by Brachyspira leads to production losses, with an estimated annual cost of circa £18 million to the commercial layer industry in the United Kingdom. Of seven known and several proposed species of Brachyspira, three are currently considered pathogenic to poultry; B. alvinipulli, B. intermedia and B. pilosicoli. Currently, AIS is primarily prevented by strict biosecurity controls and is treated using antimicrobials, including tiamulin. Other treatment strategies have been explored, including vaccination and probiotics, but such developments have been hindered by a limited understanding of the pathobiology of Brachyspira. A lack of knowledge of the metabolic capabilities and little genomic information for Brachyspira has resulted in a limited understanding of the pathobiology. In addition to an emergence of antibiotic resistance amongst Brachyspira, bans on the prophylactic use of antimicrobials in livestock are driving an urgent requirement for alternative treatment strategies for Brachyspira-related diseases, such as AIS. Advances in the molecular biology and genomics of Brachyspira heralds the potential for the development of tools for genetic manipulation to gain an improved understanding of the pathogenesis of Brachyspira.  相似文献   
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