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Infectious bronchitis virus CA99 serotype was isolated from several broiler flocks in Northern California. The virus caused late-onset respiratory disease and increased airsacculitis condemnation in affected flocks despite the use of an established infectious bronchitis virus vaccination program. An experimental study compared Holland/Arkansas and Massachusetts/Arkansas vaccination protocols to determine the efficacy of commercial infectious bronchitis virus vaccines in reducing respiratory disease and airsacculitis lesions found at processing that were associated with a CA99 field isolate. All vaccination groups were given Massachusetts/Connecticut strains of infectious bronchitis virus vaccines at age 1 day followed by vaccination with either Holland/ Arkansas or Massachusetts/Arkansas vaccine strains at 18 days of age. Birds were challenged at age 31 days with a CA99 field isolate. Gross pathology, histopathology, and virus isolation were evaluated. Chickens vaccinated with Holland/Arkansas had marginally better protection against CA99 challenge than chickens vaccinated with Massachusetts/Arkansas, although differences were not statistically significant.  相似文献   
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In this study, we characterized three variant infectious bronchitis virus (IBV) strains isolated in 2003 and 2004 from broiler chickens in California and compared them to previously isolated California variant viruses and to common vaccine serotypes used in the United States. We conducted genetic, serologic, and pathogenicity studies on all three isolates, then tested different vaccines against one of the viruses. Genetically the three variant IBV strains, designated CA557/03, CA706/03, and CA1737/04, were not related to each other. GenBank BLAST database search and phylogenetic analysis of the hypervariable region of the S1 subunit of the spike gene to determine the most closely related viruses to the three variants showed the CA557/03 variant to be 81.8% similar to the CAV/CA56b/91 whereas the CA706/03 and CA1737/04 variant viruses were only distantly related to Dutch/D1466/81 (72.2%), a vaccine strain used in Europe, and Korea/K142/02 (72.7%), a Korean field isolate, respectively. Cross virus-neutralization testing showed that none of the 2003-04 California IBV variant viruses were serologically related to each other or to Ark, Conn, or Mass vaccine strains. In addition the CA1737/04 isolate was also tested against DE072 and found not to be serologically related. All three variant viruses were pathogenic in 1-wk-old broilers and vaccination with Mass/Conn followed by Holland/Conn provided 80% protection against the CA1737/04 virus. The 2003-04 California variant viruses were not compared with variants isolated in California during 1970s and 1980s because, to our knowledge, no genetic information is available and those viruses are no longer obtainable. This study shows that the CA557/03 virus was distantly related to the CAV-type viruses isolated in California in the early 1990s, but that none of the 2003-04 viruses were similar genetically or serologically to the CAL99-type viruses, indicating that new IBV variants continue to emerge and cause disease in commercial chickens in California.  相似文献   
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A moribund juvenile gray squirrel (Sciurus carolinensis) with numerous skin fibromas was submitted to the Northeastern Research Center for Wildlife Diseases. Necropsy revealed multiple firm white nodules in the lungs. On histologic examination, in addition to the skin lesions, fibromatous proliferations were seen in the wall of the alimentary tract, in 1 mesenteric lymph node, and in the myocardium. Tubular adenomas were seen in the renal cortex, and the lung nodules were bronchoalveolar adenomas. Eosinophilic intracytoplasmic poxvirus inclusion bodies were seen in both the mesenchymal and epithelial tumors.  相似文献   
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The efficacy of trilostane in the treatment of canine pituitary-dependent hyperadrenocorticism (PDH) was evaluated in 78 dogs with the condition which were treated for up to three years. The drug appeared to be well tolerated by almost all the dogs, and only two developed clinical signs and biochemical evidence of hypoadrenocorticism. Polyuria and polydipsia completely resolved in 70 per cent of the dogs that had these problems, and skin changes resolved in 62 per cent of the dogs that had skin abnormalities. There was a significant reduction (P<0.001 in each case) in both the mean basal and post-adrenocorticotrophic hormone (ACTH) cortisol concentrations after a mean of 12.3 days of treatment. The post-ACTH cortisol concentration decreased to less than 250 nmol/litre in 81 per cent of the dogs within one month of the start of treatment and in another 15 per cent at some later time. The median survival time of the 26 dogs which died was 549 days, and 51 of the dogs were alive at the completion of the study. One was lost to follow up after 241 days treatment.  相似文献   
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Participants playing the computer game Tetris reported intrusive, stereotypical, visual images of the game at sleep onset. Three amnesic patients with extensive bilateral medial temporal lobe damage produced similar hypnagogic reports despite being unable to recall playing the game, suggesting that such imagery may arise without important contribution from the declarative memory system. In addition, control participants reported images from previously played versions of the game, demonstrating that remote memories can influence the images from recent waking experience.  相似文献   
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A 2-week-old Toggenburg kid was evaluated for persistent diarrhea and poor body condition. The herd had high morbidity and mortality associated with diarrhea in neonatal kids. Lactose intolerance was diagnosed on the basis of results of a lactose tolerance test and glucose absorption test. Clinically normal herdmates were used as control animals. The kid responded to lactase supplementation. Cryptosporidium organisms were detected in feces of several affected kids during episodes of acute diarrhea. Lactose intolerance was presumed to have developed secondary to intestinal cryptosporidiosis.  相似文献   
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U.S. packers must have quantitative criteria for selection of pork bellies and Boston butts for export to South Korea. Pork bellies (IMPS 409A) and Boston butts (IMPS 409A, 406B, 407) were selected from normal production in a U.S. pork packing plant and transported to Seoul, South Korea, via seafreighter in refrigerated containers (frozen < -5 degrees C) or via air freight (fresh > 0 degrees C; frozen < -5 degrees C). Participants at the Seoul Food Show were surveyed about their preferences for specific quality attributes of these cuts. Bellies were selected to differ in seam fat content (low = < 20%, moderate = 20 to 40%, high = > 40% extractable fat), lean color (pale = L* > 50, medium = L* 48-50, dark = L* < 48), weight (3.36, 4.04, or 5.36 kg), state of refrigeration and packaging (frozen, poly-wrapped; chilled, poly-wrapped; frozen, vacuum-packaged; chilled, vacuum-packaged), shape (round, wavy, square), and belly thickness (3.81, 4.32, or 4.90 cm). Boston butts were selected to differ in USDA marbling score (Slight, Small, Modest, Moderate, and Slightly Abundant), seam fat content (low = < 10%, moderate = 10 to 20% fat, high = > 20% extractable fat), lean color (pale = L* > 44, medium = L* 40-42, dark = L* < 38), weight (2.91, 3.82, or 4.66 kg), state of refrigeration and packaging (frozen, poly-wrapped; chilled, poly-wrapped; frozen, vacuum-packaged; chilled, vacuum-packaged), and shape (square, oblong, round). In Seoul, pork subprimals were tempered (if frozen), sliced, and arrayed by quality attribute and category in a retail display case. Over 4 d of testing, attendees (n = 210) of the food show were asked to rate the displayed samples for each quality attribute on a standardized ballot. Mid-weight (3.82 kg) Boston butts that displayed Moderate or higher USDA marbling scores with moderate amounts of seam fat, Japanese lean color scores of 2 or 4, round geometric shape, and that were vacuum-packaged and transported to Korea in the freshly chilled state best characterized the quality attribute preferences of respondents. Pork bellies that exhibited moderate amounts of seam fat, Japanese lean color scores of 3, square shape, belly thickness of 3.94 cm, approximate weight of 4.04 kg, and that were vacuum-packaged and transported to Korea in the freshly chilled state best met the quality needs of South Korean customers.  相似文献   
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