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581.
The purpose of this study was to evaluate the potential for houseflies (Musca domestica) to mechanically transport and transmit porcine reproductive and respiratory syndrome virus (PRRSV) between pig populations under controlled field conditions. The study employed swine housed in commercial livestock facilities and a release-recapture protocol involving marked (ochre-eyed) houseflies. To assess whether transport of PRRSV by insects occurred, ochre-eyed houseflies were released and collected from a facility housing an experimentally PRRSV-inoculated population of pigs (facility A) and collected from a neighboring facility located 120 m to the northwest that housed a naïve pig population (facility B). All samples were tested for PRRSV RNA by polymerase chain reaction (PCR). To assess transmission between the 2 populations, blood samples were collected from naïve pigs in facility B at designated intervals and tested by PCR. A total of 7 replicates were conducted. During 2 of 7 replicates (1 and 5), PCR-positive ochre-eyed houseflies were recovered in facility B and pigs in this facility became infected with PRRSV. Chi-squared analysis indicated that the presence of PRRSV in an insect sample was significantly (P = 0.0004) associated with infection of facility B pigs. Porcine reproductive and respiratory syndrome virus was not recovered from other reported routes of transmission during the study period, including air, fomites, and personnel. In conclusion, while an insufficient number of replicates were conducted to predict the frequency of the event, houseflies may pose some level of risk for the transport and transmission of PRRSV between pig populations under field conditions.  相似文献   
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This study was carried out to investigate the carcass characteristics of Hanwoo (Korean cattle) from different sex conditions, raising altitudes and slaughter seasons. The total number of cattle used in this study was 3608 heads which comprised of 1336 bulls and 1660 steers. The data was analyzed according to sex condition (bull and steer), raising altitude (low: 0–100 m and high: 700–800 m) and slaughter season (spring, summer, autumn and winter). At 24 h post-slaughter, the carcasses were weighed and evaluated for carcass traits according to the Korean carcass grading standard by an official grader. Carcass weight, ribeye area, yield index and grade, and meat color, firmness and maturity scores of carcass from bulls were significantly higher (P < 0.001) than those from steers. Inversely, the backfat thickness, marbling score and quality grade of carcass from steers were significantly higher (P < 0.001) than those from bulls. The maturity score of carcass from a high area was significantly higher (P < 0.01) than that from a low area. The ribeye area of carcass from summer was significantly smaller (P < 0.05) than that from other seasons. The maturity score of carcass from the summer season was highest among that from other seasons and the lowest was that from the winter season. Marbling score and carcass quality grade from the winter season were highest among those from other seasons and the lowest were those from the autumn season. There were no significant interactions between sex condition and raising altitude on carcass traits except the ribeye area. There were significant interactions between sex condition and slaughter season on marbling score and carcass quality grade. There were no significant interactions between raising altitude and slaughter season on all of the carcass traits. There were significant interactions among sex condition, raising altitude and slaughter season on meat color score. It was concluded that sex condition affected muscle and fat depositions on the carcass, raising altitude affected maturity and slaughter season affected ribeye area, maturity and marbling.  相似文献   
585.
Protamine is a basic protein whose sulfate is used in medical applications as a carrier for injectable insulin and as a heparin antagonist, while its hydrochloride is used as an antibacterial ingredient for some food products. We previously showed that protamine hydrochloride derived from chum salmon milt inhibited pancreatic lipase and reduced plasma triacylglycerol levels in an oral fat tolerance test in humans. The present study evaluated the effect of chum protamine hydrochloride on lipid metabolism in rats. The single oral administration of protamine hydrochloride (500 mg/kg) reduced plasma triacylglycerol levels in a corn oil tolerance test, and repeated oral administration at a dose of 0, 150, 500, or 1,500 mg/kg with a high fat diet for 7 weeks significantly reduced body weight gain, liver weight, and epididymal adipose tissue, whereas total calorie intakes were not significantly different. These findings could be caused by the suppression of lipid digestibility leading to a significant increase in fecal lipid excretion due to the fact that protamine hydrochloride could bind with bile acids to make a complex that is difficult to digest. Protamine hydrochloride, with a considerable history as food, can be considered to be promising as an anti-obesity functional food material.  相似文献   
586.
A 2.5-kg castrated male Maltese dog, suspected to be older than 10 y, was presented with a prolapsed mass at the anus. This had occurred on 2 previous occasions within the last 4 mo and had been managed with manual reduction and purse-string sutures. The rectal prolapse had viable tissue and was reducible but resulted in straining and fecal accumulation. Colopexy (with intracorporeal sutures) was performed laparoscopically using 3 ports; the distal colon was retracted cranially and attached to the abdominal wall with 3 simple interrupted sutures in a single row. The dog recovered uneventfully, had good appetite and normal activity, did not strain, and defecated without issues. There were no wound-healing complications and at 12-month post-operative examination, the patient was in good condition without clinical signs. Based on this case report, laparoscopic colopexy is clinically practical for management of rectal prolapse in small-breed dogs.  相似文献   
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To evaluate the biological effects of Porphyra tenera (P. tenera), we tried to confirm the possibility that the intake of P. tenera could modulate cognitive and intestinal functions in PM2.5-induced cognitive decline mice. P. tenera attenuated PM2.5-induced learning and memory impairment through antioxidant and anti-inflammatory effects by regulating the mitochondrial function and TLR-initiated NF-κB signaling. In addition, P. tenera effectively alleviated Aβ production/tau phosphorylation by inhibiting the JNK phosphorylation. Also, the bioactive constituents of P. tenera determined the sulfated galactan, mycosporine-like amino acids (MAAs), and chlorophyll derivatives. Moreover, the bioactive compounds of P. tenera by gut fermentation protected against gut dysbiosis and intestinal tight junction damage with a decrease in inflammatory response and short-chain fatty acid production. Based on these results, our findings suggest that P. tenera with sulfated galactan and MAAs is a potential material for cognitive function improvement.  相似文献   
589.
Two new lipo-decapeptides, namely taeanamides A and B (1 and 2), were discovered from the Gram-positive bacterium Streptomyces sp. AMD43, which was isolated from a mudflat sample from Anmyeondo, Korea. The exact molecular masses of 1 and 2 were revealed by high-resolution mass spectrometry, and the planar structures of 1 and 2 were elucidated using NMR spectroscopy. The absolute configurations of 1 and 2 were determined using a combined analysis of 1H-1H coupling constants and ROESY correlations, the advanced Marfey’s method, and bioinformatics. The putative nonribosomal peptide synthetase pathway for the taeanamides was identified by analyzing the full genome sequence data of Streptomyces sp. AMD43. We also found that taeanamide A exhibited mild anti-tuberculosis bioactivity, whereas taeanamide B showed significant bioactivity against several cancer cell lines.  相似文献   
590.
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