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A restraint and transport system was developed for handling large swine during cardiovascular research studies. The major design criteria provided for comfortable, low stress restraint of the swine, safety for laboratory personnel and ability to perform a wide variety of hemodynamic and echocardiographic measurements in the standing, supported standing and sedated, or in Panepinto sling positions. A head gate is provided for venipuncture procedures, and an auxiliary feeding and watering front panel can replace the head gate for use of the system as a post-operative "recovery room". Using this system animals weighing 22 to 150 kg can be easily managed.  相似文献   
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Bovine keratoconjunctivitis (BKC), colloquially referred to as 'pinkeye', is a disease affecting cattle worldwide; it costs cattle producers millions of dollars in economic loss annually. While Moraxella spp. are the primary etiologic agent of pinkeye, surveys of flora from the conjunctivae of livestock from around the world have indicated that a variety of bacterial commensals occupy this niche. We used molecular biology-based methods to determine the composition of bacterial flora in the conjunctivae of normal dairy and beef cattle from Maryland (n=113), and beef cattle with clinical BKC from Louisiana (n=42). Three regimens were used: 16S rRNA PCR and DGGE analysis of amplicons; 16S rRNA PCR and cloning of amplicons into Escherichia coli followed by screening and sequencing of clones harboring inserts; and culture of bacteria on chromogenic agar followed by 16S rRNA PCR and sequencing. Most taxa were comprised of saprophytes found in the environment, such as Bacillus, Pantoea, E. coli, and Exiguobacterium. Moraxella spp. were infrequently observed. Some species, such as Propionibacterium acnes, represent taxa not previously associated with the conjunctivae. Bacillus pumilus and Bacillus licheniformis isolates from the conjunctivae of Maryland cattle were genetically distinct from isolates previously implicated in septic infections in cattle at the same location. We conclude that employing 16S rRNA-based methods for bacterial identification can be useful in defining the flora present in the conjunctivae of normal cattle, and those with BKC.  相似文献   
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Hydrolyzates of aqueous extracts of Apollo 11 fines, an Apollo 12 trench sample, and an Apollo 12 surface sample have been analyzed on an ultrasensitive amino acid analyzer. The total content of amino acids recovered ranged from 20 to 70 parts per billion of lunar soil. Amino acids are not recovered by the direct hydrolysis of lunar fines, presumably because of decomposition in the presence of the large excess of lunar mineral. As judged by retention time, glycine is the dominant amino acid found; alanine is secondarily present in each case in the profile. Only a few amino acids have been recorded in each analysis. The pattern is relatively consistent in the samples from the three locations; the pattern from either hydrolyzed or unhydrolyzed extracts differs markedly from that of hydrolyzed or unhydrolyzed handprints. The evidence is not consistent with contamination of the kind expected by many investigators.  相似文献   
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A short calving to conception interval is of main importance to achieve high economic efficiency in dairy cow industry. In order to reduce this interval, several hormonal treatments have been put on the market, in which cloprostenol, a synthetic analogue of prostaglandin F2alpha (PGF2alpha). The aim of this study was to compare fertility of cloprostenol-induced oestrus to that of spontaneous oestrus in dairy cows. In a group of 525 cows, 280 (treated group) were administered 0.5 mg cloprostenol i.m. after transrectal corpus luteum (CL) detection, and inseminated at detected oestrus during the following week. The other 245 cows (control group) were inseminated during spontaneous oestrus. Whey progesterone concentrations were checked at treatment and at insemination in order to remove from the study cows whose P4 levels indicate a non-functional CL, or a lack of luteolysis respectively. Moreover, cows that were not inseminated due to genital problems were also excluded from this study. Conception (59% vs 54.5%) and calving rates (93.7% vs 93%) were not significantly different between the two groups.  相似文献   
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