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981.
A second gene conferring resistance to the chickpea wilt pathogen, Fusarium oxysporum f. sp ciceris race 0, has been mapped to linkage group 2 (LG2) of the chickpea genetic map. Resistance to race 0 is controlled by two genes which segregate independently; one present in accession JG62 (Foc0 1 /foc0 1 ) and mapping to LG5 and the second present in accession CA2139 (Foc0 2 /foc0 2 ) but remaining unmapped. Both genes separately confer complete resistance to race 0 of the wilt pathogen. Using a Recombinant Inbred Line (RIL) population that segregated for both genes (CA2139 × JG62) and the genotypic information provided by two markers flanking Foc0 1 /foc0 1 ten resistant lines containing the resistant allele Foc0 2 /foc0 2 were selected. Genotypic analysis using these ten resistant lines paired with ten susceptible RILs, selected in the same population, revealed that sequence tagged microsatellite sites (STMS) markers sited on LG2 were strongly associated with Foc0 2 /foc0 2 . Linkage analysis, using data from two mapping populations (CA2139/JG62 and CA2156/JG62), located Foc0 2 /foc0 2 in a region where genes for resistance to wilt races 1, 2, 3, 4 and 5 have previously been reported and which is highly saturated with tightly-linked STMS markers that could be used in marker-assisted selection (MAS).  相似文献   
982.
Feces from 1,451 horses entering a veterinary hospital over a 13-month period were cultured for salmonella. A total of 46 horses (3.2%) yielded 1 or more salmonella-positive fecal cultures. Twenty horses were found to be excreting salmonella in the feces on admission, and 5 of these later had severe diarrhea associated with enteric salmonellosis. Abdominal surgery and other severe stresses were associated with all cases of severe enteric salmonellosis. Serotypes of salmonella isolated included Salmonella agona (15), S anatum (14), S typhimurium (7), S typhimurium var copenhagen (4), S infantis (2), S montevideo (1), S meleagridis (1), S drypool (1), and an unnamed Salmonella serotype (1). Seven deaths were attributed to 4 serotypes (S typhimurium, 3; S anatum, 2; S typhimurium var copenhagen, 1; and S montevideo, 1). A marked seasonal incidence is isolations was found with isolations highest in later summer to early fall and lowest in the spring. It was also found that horses can shed salmonella intermittently, and a minimal of 5 consecutive negative fecal cultures is recommended before considering a horse not to be infected with salmonella.  相似文献   
983.
Food systems educators face a double challenge: (1) the inherent change in scope and perspective from raising animals to producing safe food in an environmentally conscientious manner; and (2) the unprecedented demand for higher education, both nationally and internationally. In the modern world, small numbers of producers are capable of feeding a growing population. As demographics have shifted from rural to urban areas, more global livelihoods are derived from manufacturing and services than from agriculture. Education, as one of those services, is accounting for an increasing percentage of world trade, through the physical translocation of students and, more recently, through online education. Within the veterinary realm, colleges outside the United States seek accreditation to better compete for students, and there is increasing pressure from private schools. Today's food systems require a high level of veterinary expertise, with specialization in a particular production system as well as the ability to contribute as part of a larger team that can address economic, bio-security, biological-waste, animal-welfare, food-safety, and public-health concerns. The need for different expertise from food systems specialists (indeed, shortages of all types of veterinary specialists), combined with global competition in education, is a call to action for the veterinary profession. This is an opportunity to revisit and reorganize the delivery of veterinary education, making use of new collaborative technologies for greater efficiency and effectiveness.  相似文献   
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988.
History, physical examination, and bone scintigraphy were used to diagnose central and/or third tarsal bone trauma in 3 acutely lame horses. In all 3 cases, the results of initial radiographic examination were negative. Bone scintigraphy revealed focal, intense radioisotope uptake at the level of the distal tarsal bones in the 3 horses. Radiographs obtained 4 weeks after injury in one horse demonstrated a slab fracture of the central tarsal bone. Conservative management of the tarsal bone disease resulted in acceptable return to function in all 3 horses.  相似文献   
989.
We describe a rare case of a concurrent demodectic and sarcoptic mange in a 2-year-old heifer in Khartoum, Sudan. The lesions were massive lumps of granulomatous tumour-like dermatitis with thick, nodular folds mainly covering the head, neck and shoulders. Histopathological examination of the lesions revealed the presence of both Demodex bovis and Sarcoptes scabiei. The animal died regardless of the anti-parasitic treatment it received.  相似文献   
990.
The phylogeny of the genus Udonella has been disputed for quite some time, but recent phylogenetic analysis of molecular data confirms that the genus is a monopisthocotylean monogenean. Specimens of Udonella myliobati parasitizing the copepod Lepeophtheirus natalensis, an ectoparasite of the spotted ragged-tooth shark, (Carcharias taurus), were collected and studied. A total of 771 monogenean specimens were recovered from 54 infected copepods examined, with a mean intensity of 14,3 worms per copepod. Most of the monogeneans were found attached to the dorsal surface of the lateral and frontal marginal membranes of the copepod carapace. Eggs, with filaments and adhesive discs, were found ventrally on the host, mainly attached to the maxillae and maxillipeds, in clusters of 12-14. Observations on the morphology, distribution and behaviour of this monogenean are presented with the aid of light and scanning electron microscopy.  相似文献   
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