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71.
James E. Smallwood DVM MS Sandra M. Albright DVM Michael R. Metcalf DVM MS Donald E. Thrall DVM PHD Ben D. Harrington DVM 《Veterinary radiology & ultrasound》1989,30(3):98-110
The purpose of the project was to provide a reference for radiographic anatomy of the developing equine foredigit and metacarpophalangeal region. Using xeroradiographic techniques, both foredigits and meta-carpophalangeal regions of six Quarter Horse foals were radiographed at one day of age and at two-week intervals until the foals were six weeks old. The foals were then radiographed at four-week intervals until they were 12 months old. This report deals specifically with the first six months of postnatal development. Lateromedial and dorsopalmar xeroradiographs of each foredigit and metacarpophalangeal region and a dorsal 65° proximal-palmarodistal oblique view of the distal part of the digit were made for each examination. The foals were weighed and measured at the withers immediately prior to each examination. Representative xeroradiographs were selected and appropriately labeled to demonstrate normal radio-graphic anatomy of these regions. First radiographic appearance of distal epiphyseal ossification in metacarpal 2 and metacarpal 4 was extremely variable and ranged from four to 38 weeks. Radiographic closure of the proximal physis of the middle phalanx ranged from 18 to 30 weeks (mean = 26 weeks). Radiographic closure of the proximal physis of the proximal phalanx ranged from 22 to 38 weeks (mean = 30 weeks). Radiographic closure of the distal physis of metacarpal 3 ranged from 18 to 38 weeks (mean = 29 weeks). When xeroradiographic physeal closure times were compared with scintigraphic closure times from a companion study, results correlated very well. A crena marginis solearis was observed in ten of 12 forelimbs (83.3%); its first radiographic appearance ranged from four to 22 weeks (mean = 11–12 weeks). A consistent groove in the hoof wall, which formed near the time of birth and moved distally at about 3 mm per week, was noted. The groove's distance from the proximal hoof border may be useful in age estimation of foals less than 18–20 weeks old. 相似文献
72.
Ceratocystis cacaofunesta (= Ceratocystis fimbriata ) causes a lethal wilt disease of cacao ( Theobroma cacao ) in Latin America. Polymorphic microsatellite markers, (CAT)5 nuclear DNA fingerprints and Hae III mitochondrial DNA fingerprints were used to compare genetic diversity among isolates of C. cacaofunesta collected from populations in western Ecuador, Costa Rica, Colombia, and Rondônia and Bahia in Brazil. Microsatellite markers and nuclear DNA fingerprints separated Ecuadorian isolates from isolates of the other four populations, and these two major groups correspond to genetic lineages already identified from ITS-rDNA sequences and intersterility groupings. Mitochondrial DNA fingerprints also demonstrated substantial diversity and split the Ecuadorian isolates into two groups. All marker types showed limited variation in the Colombian, Costa Rican and Bahian populations, as might be expected for introduced populations that have gone through recent genetic bottlenecks. In contrast, the Rondonian and western Ecuadorian populations showed gene diversity values similar to natural populations of other Ceratocystis species. The Rondonian population was the only sampled population in the native range of T. cacao (the Upper Amazon), and the putatively introduced populations were more closely related to the Rondonian population than to the western Ecuadorian population. The Ecuadorian population is in an area with other native Theobroma species, which may serve as natural hosts. 相似文献
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The occurrence of salmonellas and Erysipelothrix rhusiopathiae in tissues of swine was determined by bacteriologic and fluorscent antibody examination of 5,297 specimens from herds investigated for hog cholera. Of the specimens examined, 35.5% were positive for salmonellas, 21.1% were positive for E rhusiopathiae, and 8.3% were positive for both salmonellas and E rhusiopathiae. 相似文献
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Eric A. S. la Croix Solomon E. Mhasalkar Patrick Mamalis Frank P. Harrington 《Pest management science》1975,6(5):491-496
A series of analogues of the larvicide tenuazonic acid [3-acetyl-5-(l-methylpropyl)-pyrrolidine-2,4-dione] was prepared in an attempt to increase its activity and breadth of spectrum. Substitution brought about some changes in specificity, the greatest improvement being obtained with chlorophenyl substituents. 相似文献
80.
: Tetanus with hiatal hernia was diagnosed in a four-month-old female sheepdog pup. The animal was treated with tetanus antitoxin, antibiotics, fluids and intensive nursing care for three weeks and subsequently made a full recovery. 相似文献