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21.
A 19-year-old horse that was one of a group of six horses infected experimentally with Anaplasma phagocytophilum for a study of the pathogenesis of equine granulocytic ehrlichiosis died suddenly two days after first showing clinical signs of disease. The clinical signs and laboratory findings observed before its death were similar to all those of the other infected horses, and to previous reports of this disease. A postmortem examination revealed widespread haemorrhaging in its internal organs, and vasculitis and thrombosis in the kidneys. These changes are consistent with disseminated intravascular coagulation, which has previously been reported in human beings infected with the presumably identical agent of human granulocytic ehrlichiosis.  相似文献   
22.
OBJECTIVE: To determine the effect of dietary supplemental lipoic acid (LA) on serum concentrations of metabolic hormones and acute-phase proteins of steers challenged with infectious bovine rhinotracheitis virus (IBRV). ANIMALS: 32 steers. PROCEDURES: Steers were randomly assigned to 4 treatments: negative control (NC; no LA, no IBRV challenge), control (CON; no LA, IBRV challenge), 16 mg of LA/kg of body weight (BW)/d plus IBRV challenge (LA16), and 32 mg of LA/kg of BW/d plus IBRV challenge (LA32). Following a 21-day adaptation period, CON, LA16, and LA32 steers received IBRV (2 mL/nostril [day 0]); NC steers received saline (0.9% NaCl) solution. Blood samples, nasal swab specimens, BW, and rectal temperatures were obtained 0, 1, 3, 5, 7, 14, and 21 days after challenge. Serum was analyzed for concentrations of haptoglobin, amyloid-A, leptin, and anti-IBRV antibodies. RESULTS: Steers fed LA32 began gaining BW by day 7, whereas BW of CON and LA16 steers declined. Serum haptoglobin concentration of LA32 steers was lower than that of CON and LA16 steers on day 7. Serum neutralization titers for 30 of 32 steers were negative for anti-IBRV antibodies before challenge; however, all steers (including NCs) had antibodies on day 21. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that LA supplementation augmented certain aspects of the immune response; LA32 steers had a more rapid recovery from IBRV viral challenge than did others.  相似文献   
23.
Progeny (n = 70) from unrelated, DNA tested, Rendement Napole carrier (RN-/rn+) Hampshire sires, and DNA tested, Rendement Napole normal (rn+/rn+) Yorkshire dams were genotyped for the segregating RN- allele via DNA marker-assisted methodology. Six slaughter groups ensued, with littermates all being represented within the same slaughter group. Boneless pork loins were removed from right carcass sides after a 48-h chill at 2 degrees C. The anterior portions of the loins were not enhanced, whereas the posterior sections were enhanced with a solution containing 0.5% sodium chloride and 0.5% sodium tripolyphosphate to 110% of their initial weight. Carcasses of carrier pigs had less (P < 0.05) 10th rib fat depth and a greater (P < 0.01) percentage carcass lean than carcasses of normal pigs. Postmortem LM pH of carrier pigs was lower (P < 0.002) at 3, 6, 12, and 24 h, and tended to be lower (P = 0.062) at 48 h compared with that of normal animals. Samples of LM from carrier pigs had greater (P < 0.01) glycolytic potential values, drip loss percentages, and a* values, and lower pH values at fabrication than LM from normal pigs. No genotype differences (P > 0.05) were found for LM lactate, L*, or b* values. Nonenhanced semimembranosus samples from carrier pigs exhibited greater (P < 0.05) purge loss percentages and L* values, and lower (P < 0.01) pH values than samples from normal pigs. Enhanced LM samples exhibited greater (P < 0.05) drip and purge loss percentages, greater pH, and lower L* values at fabrication, regardless of Napole status. These findings suggest that the Napole gene has a positive influence on carcass leanness but detrimental effects for lean quality, which were often further compounded when meat was subjected to enhancement treatment.  相似文献   
24.
AZD3783, a cationic amphiphilic drug and a potent inhibitor of the 5-hydroxytryptamine (5-HT1B) receptor, was explored as a potential treatment for depression. To support clinical trials, repeat dose toxicity studies in rats and dogs were conducted. Here we report toxicity findings in dogs after dosing from 1 to 3 months. In the 1-month study, there were minimal neuronal vacuolation in the brain, a marked increase in liver enzymes accompanied by hepatocellular degeneration/necrosis and phospholipidosis (PLD), and PLD/cholecystitis in the gallbladder of animals dosed at 47 mg/kg/day. In the 3-month study, neurotoxicity resulted in euthanasia of one animal dosed at 30 mg/kg/day after 86 days. Extensive pathologic changes were seen in all animals in retina epithelium (inclusion bodies), brain (neuronal vacuolation, degeneration, or necrosis and nerve fiber degeneration), spinal ganglia (vacuolation, degeneration, or necrosis), as well as sciatic and optic nerves (degeneration). Pigment-laden macrophages were observed in the lung, kidney, liver, gallbladder, bone marrow, gastrointestinal tract, and lymphoid tissues. Also seen were vitrel and retinal hemorrhage in the eyes. A brain concentration and pathology study showed that the concentration of AZD3783 in the brain was approximately 4 times higher than in the plasma after 4 weeks of dosing, however, they were similar in all regions examined, and did not correlate with areas with pathologic findings. Our findings with AZD3783 in dogs have not been reported previously with other CNS compounds that effect through serotonergic pharmacology.  相似文献   
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26.
Epizootic ulcerative syndrome was diagnosed, and the presence of Aphanomyces invadans confirmed, from an outbreak of clinical disease in wild‐caught bony bream (Nematalosa erebi) from the Darling River near Bourke, in New South Wales, Australia, during 2008. This confirms a significant extension of the agent beyond its historical range.  相似文献   
27.
tests, based on the polymerase chain reaction ( ), were developed for the detection of two breed-specific mutations responsible for the autosomal recessive disorder bovine α-mannosidosis. The tests involve separate amplification of two exons of the lysosomal α-mannosidase gene followed by restriction enzyme digestion of the amplicons. We demonstrate that one of the mutations, the 662G→A transition, is responsible for α-mannosidosis in Galloway cattle. The other mutation, the 961T→C transition, is uniquely associated with α-mannosidosis in Angus, Murray Grey and Brangus cattle from Australia. The 961T→C mutation was also detected in Red Angus cattle exported from Canada to Australia as embryos. All 39 animals classified as heterozygotes on the basis of biochemical assays were heterozygous for one of the two mutations. None of 102 animals classified as homozygous-normal on the basis of biochemical assays possessed the mutations. Our results indicate that the two breed-specific mutations may have arisen in Scotland and by the export of animals and germplasm disseminated to America, New Zealand and Australia.  相似文献   
28.
This study was carried out to assess the effects of variety, year, location and level of fertilizer application on chemical composition and in sacco dry matter (DM) degradability of durum wheat straw as well as to understand the relationship between straw quality and agronomic traits of the crop and to assess the possibilities of selecting wheat varieties that combine high grain yield with desirable straw quality. Two local (Arendeto and Tikur sinde) and two improved (Boohai and Gerardo) varieties of durum wheat (Triticum turgidum Desf.) were used in the experiment. The four varieties were grown at two locations (Akaki and Ejere) in the years 2001/2002 and 2002/2003 in 5 x 5 m plots in three replications. Diammonium phosphate and urea fertilizers were applied at four levels (0/0, 32/23, 41/23 and 64/46 kg/ha of nitrogen/phosphorus). Straw quality was assessed based on chemical composition and in sacco DM degradability. Correlation of straw quality with grain and straw yield and with other agronomic characteristics of the crop was determined. The potential utility index (a measure that integrates grain and digestible straw yield) was used for ranking of the varieties. The local varieties had higher crude protein (CP) and lower neutral detergent fibre contents and higher digestibility than the improved varieties. The cropping year and location had significant effect on CP content and degradability of the straw, which could be due to climatic variation. However, the fertilizer level did not have any significant effect on straw quality except that the CP content of the straw tended to increase with increasing level of fertilizer application. Based on the potential utility index the varieties ranked, in a decreasing order, as Tikur sinde > Arendeto > Gerardo > Boohai and the ranking was consistent across years and locations. Except the CP content, straw quality was not negatively correlated with grain and straw yield. This indicates that there is a possibility of selecting varieties of wheat that combine high grain and straw yield with desirable straw quality.  相似文献   
29.
Radioimmunochemical detection (RIA) following fractionation of urine extracts via high performance liquid chromatography (HPLC) turned out to be a very specific method for the identification of stilbene derivatives in bovine urine. Combination of the high resolution of the HPLC with a specific RIA is a suitable method to discriminate between the presence of different stilbene derivatives like diethylstilboestrol (DES), dienoestrol (DE) and hexoestrol (HEX) or other unknown compounds interfering in the celite-RIA used in the screening. Using this screening method 8200 samples of bovine urine were investigated on the presence of stilbene derivatives of which 133 were classified as 'positive'. In 106 'positive' urines the presence of DES was shown and in 19 'positive' urines the presence of DE or HEX, using the method described in this report whereas in 8 'positive' urines an unknown immunochemical active compound was detected. During 1.5 year of comparative investigation no qualitative discrepancies occurred between the results of the HPLC-immunogram procedure and the final confirmation by high resolution gas chromatography-mass spectometry (GCMS).  相似文献   
30.
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