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991.
992.
We characterized the nearly complete coding sequence of the pig 2,4-dienoyl CoA reductase 1 (DECR1) gene, which encodes an enzyme involved in the beta-oxidation of polyunsaturated fatty enoyl-CoA esters and maps on a linoleic QTL located on Chromosome 4. Sequencing of a 937-bp fragment encompassing exons 2 and 10 revealed the existence of two missense SNP at exon 2 (C181 --> G181) and exon 5 (C458 -->G458). These two SNP are associated with Val (C) --> Leu (G) and Ser (C) --> Thr (G) conservative AA replacements at positions 61 and 153 of the DECR1 protein, respectively. Moreover, DECR1 genotyping in a representative sample of 184 pigs from the Large White, Pietrain, Iberian, Duroc, and Landrace breeds demonstrated the existence of disequilibrium linkage between these two SNP (Haplotype 1: C181C458; Haplotype 2: G181G458). An association analysis between DECR1 genotype and growth, carcass, and meat quality traits in a highly selected Landrace population (n = 470) revealed differences among genotypes for isocitrate dehydrogenase activity (highest posterior density [HPD] of 90%), longissimus thoracis pH (HPD of 95%), lightness (HPD of 90 to 95%), and redness (HPD of 95%). Because these associations were not consistently found in the three available genotype comparisons, we believe that exon 2 and 5 polymorphisms at the DECR1 gene might be in linkage disequilibrium with the true causal mutation influencing isocitrate dehydrogenase activity and muscle color and pH.  相似文献   
993.
OBJECTIVE: To compare the rate of gastric emptying of a semisolid meal by use of the carbon 13-labeled octanoic acid breath test (13C-OBT) and gastric emptying ultrasonography (GEU) in dogs. ANIMALS: 10 healthy dogs. PROCEDURE: Food was withheld from dogs for 12 hours before ingestion of a test meal (bread, egg, and skimmed milk) containing 13C-octanoic acid. The gastric antrum was visualized by use of a 6.5-MHz microconvex transducer, and the area of the ellipse defined by the craniocaudal and ventrodorsal diameters of the stomach was measured. Samples of expired air and antral images were obtained 30 minutes before ingestion of the test meal and then every 15 minutes for 4 hours and every 30 minutes for a further 2 hours. The half-dose recovery time with the 13C-OBT (t1/2[BT]) and the gastric half emtying time with GEU (t50%[GEU]) was calculated. RESULTS: Mean +/- SD values for the t1/2(BT) and t50%(GEU) were 3.44 +/- 0.48 hours and 1.89 +/- 0.78 hours, respectively. A significant correlation was detected between the t1/2(BT) and t50%(GEU), although there was a large (1.55 hours) mean difference between these indices. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that there was a correlation between the rate of solid-phase gastric emptying assessed by use of GEU and the 13C-OBT in dogs. Gastric emptying ultrasonography may be a useful, noninvasive method for assessment of the rate of solid-phase gastric emptying in dogs.  相似文献   
994.
995.
Four serological tests were evaluated for their ability to detect passively acquired maternal antibodies to Bovine herpesvirus 1. A blocking enzyme-linked immunosorbent assay demonstrated superior sensitivity in the detection of such antibodies in calves up to 9-11 months old, versus calves up to 7 months old for other tests.  相似文献   
996.
997.
998.
This case describes an outbreak of low pathogenic hemagglutinin 9 neuraminidase 2 avian influenza virus (AIV) in two white-bellied bustards (Eupodotis senegalensis), one stone curlew (Burhinus oedicnemius), and a blacksmith plover (Antibyx armatus) in a private zoologic collection in Dubai, United Arab Emirates. The four birds showed signs of respiratory disease, and all died as a result of disease or euthanasia. Attention has been paid to the diagnostic process and common differential diagnosis for upper respiratory tract disease in bustards, curlews, and plovers. To the knowledge of the authors, AIV has not been previously described in these species.  相似文献   
999.
1000.
霉菌毒素研究自20世纪60年代以来一直是个热门课题,世界霉菌毒素研讨会及美国霉菌毒素委员会为我们提供了丰富的资料。在中国,由于实验条件的限制,霉菌毒素研究领域比较落后,饲料业及养殖业对霉菌毒素的了解严重不足,这种认识上不足导致中国市场出现许多低效或无效产品。消费者  相似文献   
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