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951.
952.
饲料中娄地青霉(P.roqueforti)的检测 总被引:5,自引:0,他引:5
饲料中霉菌及其毒素的污染严重影响畜牧生产和人类健康 ,娄地青霉 (P .roquefortin)是饲料中新近发现的产毒霉菌 ,特别是在青贮饲料中有较高的检出率。其所产毒素对动物有明显的毒性作用 ,值得重视。本试验检测了 1 1 1份饲料样品 ,分别来自德国和中国的猪场、牛场以及鸡场 ,包括玉米、玉米青贮、牧草青贮以及混合饲料和牧草在内的多种饲料。通过霉菌形态学检查 ,对上述样品进行了全面检测 ,确定饲料中霉菌的含量为 2 0 0~ 8 0 0CFU/g饲料 ,青贮料中的优势菌为娄地青霉 相似文献
953.
为使刺网网目受力均匀,改善网目变形和减小目脚张力,作者用理论分析和实验方法说明中层流网处于均流状态的水中与水流没有相对位移;设计制作实验装置,用静力学模拟法试探刺网网衣上受力分布的规律,得出了浮、沉子档间距与网高之间的关系式;进而提出了合理分布浮沉子的三项原则及减小目脚张力的措施。 相似文献
954.
Samples of 51 mink feeds and 101 raw material batches were analysed for pathogenic staphylococci. Of the feed samples 37 % were contaminated with pathogenic staphylococci, the mean count being 3.02 log CFU (colony forming units)/g and the highest count being 4.48 log CFU/g of feed. Of the raw materials investigated, slaughter-house offals were most frequently contaminated and contained highest counts of S. aureus, 60 % of the samples being positive with a mean log count of 3.86/g and a maximum of 5.70/g. Forty-eight staphylococcal isolates were tested for eniterotoxin production. Toxin A, B or G were produced by eight isolates, A being the most common. None of the isolates produced B or E toxins. 相似文献
955.
T Juokslahti 《Acta veterinaria Scandinavica》1979,20(4):562-571
Mink feed raw materials were analyzed for total bacterial count, the number of faecal streptococci, the coliform count, the number of haemolytic bacteria and the number of sulphite reducing bacteria. The investigation comprised samples from the following raw materials: four slaughter-house offal products, preserved and unpreserved slaughter blood, Baltic herring, cod filletting offal, fish silage, blood meal, fish meal, meat-bone meal, protein concentrate, brewer’s yeast and cereal feed.The slaughter-house offals and unpreserved slaughter blood had the poorest quality, in terms of all the bacterial types for which the samples were analyzed. There were statistically significant differences in bacterial contents between slaughter-house offals from different sources. The preserved slaughter blood had significantly lower bacterial contents as compared to the unpreserved slaughter blood. Single samples of the cod filletting offal, Baltic herring and the blood meal had relatively high total bacterial counts, but the specified mean bacterial counts were relatively low. The bacterial counts for the rest of the investigated raw materials were relatively low. 相似文献
956.
957.
Tapio Juokslahti 《Acta veterinaria Scandinavica》1980,21(4):504
Blood samples from 100 minks from a research farm using bacteriologically high quality feed and from 55 minks from another farm supplying bacteriologically inferior feed, as well as from nine minks from Denmark from two farms providing still better quality feed than both Finnish farms – all minks apparently clinically healthy – were analyzed for some haematological and chemical data: total leucocyte count, haemoglobin, ornithine carba-moyltransferase (OCT), alkaline phosphatase (AP), alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT), γ-glutamyl-transferase (Γ-GT), total bilirubin and creatinine. The Finnish minks supplied with high quality feed had more optimal values of total leucocytes, haemoglobin, OCT, AP and creatinine than minks receiving feed with higher bacterial contamination. The Danish minks had better blood values in the investigated parameters except for lower haemoglobin and total bilirubin, which showed no significant difference. 相似文献
958.
Tapio Juokslahti 《Acta veterinaria Scandinavica》1978,19(4):520
Frozen samples of Finnish ready-mixed mink feed were analyzed for total bacterial count, the number of faecal streptococci, the coliform count, the number of haemolytic bacteria and the number of sulphite-reducing bacteria. The investigation comprised 242 feed samples from 38 central kitchens and larger private farm kitchens, the combined feed production of which is about 85 % of the yearly feed production of Finland.Of all samples 48.3 % had a total bacterial count of 106 … 6} × 106 bacteria per g of feed. The total bacterial count was relatively constant during the first four production periods of the year (December-August) and was elevated during the last period (September-November). The percentage of samples containing less than 2.5 × 104 faecal streptococci per g of feed was 49.8 %; 62 % of the samples contained less than 2.5 × 104 coliform bacteria per g. The content of coliform bacteria was lowest during the third production period (May); 48.5 % of the samples contained 5 × 103 … 105 haemolytic bacteria per g, and 4.6 % were negative. The content of haemolytic bacteria was relatively constant during the whole production year; 52.6 % of the feed samples contained 5 × 103 … 105 sulphite-reducing bacteria per g, and 17.2 % were negative. The mean content of sulphite-reducing bacteria was lowest during the second production period (March-April).The results are discussed and compared with corresponding results from Norway and Denmark. 相似文献
959.
对不同温湿度时域对不育系花时的生态效应进行了报道。试验结果表明,当不育系在温高湿大时域抽穗开花时,不育系的花时相对提早且较集中,与恢复系花时相遇率相对要好,不育系的柱头外露率增加,花粉萌发率提高。不育系的异交结实率得到明显提高(提高9.62%~11.46%)。 相似文献
960.
L. O. Wosu 《Comparative immunology, microbiology and infectious diseases》1984,7(3-4):201-206
Standardised procedure for obtaining reproducible haemagglutination-inhibition results for FPV antibody which correlate with serum-neutralization titres was described. Optimal conditions were found to be Alsevers anticoagulant, PBS/0.05% BSA (pH 6.8) as buffer, especially washed round bottom microplates, determination of maximally sensitive porcine erythrocytes, use of reproducible erythrocyte concentrations, inactivation of serum samples at 56 degrees C for 30 min and serum treatment with koalin pH 9.0. The concentration of erythrocyte used for estimation of haemagglutination units in H1 test should not differ from that used as indicator in the test. Predilution of serum beyond 1:4 associated with false results. Reproducible method for removing natural agglutinins in serum by adsorption with erythrocytes was described. 相似文献