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101.
The concentration of trimethoprim and sulphadoxine in plasma and tissue from goats and a cow have been determined after a single intravenous injection. Furthermore, the concentration of the two drugs and their metabolites in plasma and tissues have been determined after continuous intravenous infusion for 2½–3 hrs. Trimethoprim was present in all tissues but brain at higher concentrations than in plasma while the concentration of sulphadoxine in the different tissues were lower than in plasma. The highest concentration of the 2 drugs and their metabolites was found in the kidney. The distribution pattern of trimethoprim and sulphadoxine was similar in cow and goats. 相似文献
102.
Agerholm, J.S., A. Basse and K. Christensen: Investigations on the occurrence of hereditary diseases in the Danish cattle population 1989-1991. Acta vet. scand. 1993, 34, 245-253.– The methods of the Danish Bovine Genetic Disease Programme are outlined, and the results obtained during the first 3 years in function are described. The most common disease reported was spinal muscular atrophy in calves of the Red Danish Dairy breed with 312 reports. Necropsy was performed on 162 cases, and spinal muscular atrophy was diagnosed in 82 of these. Bovine progressive degenerative mye-loencephalopathy, rectovaginal constriction, syndrome of arthrogryposis and palatoschisis, hereditary chondrodysplasia (2 different types), syndactylism, epitheliogenesis imperfecta, and osteogenesis imperfecta was diagnosed with 1 case each. Lethal trait A46 was diagnosed in 4 calves. Some of these diseases have not previously been described in Denmark, and epitheliogenesis imperfecta was for the first time diagnosed in the Hereford breed. Chromosome translocation 1/29 was detected in the Blonde d’Aquitaine (BAQ), Limousine, and Red Danish Dairy breed. The aberration occurred frequently in BAQ. Furthermore, a complex chromosome translocation t(l;8;9)(q45;ql3;q26) was detected in the Red Danish Dairy breed. 相似文献
103.
104.
Growing and laying chickens were fed graded levels of selenium in the form of sodium selenite. One day old Norwegian bred broiler chickens and 20 weeks old Norwegian bred White Leghorn chickens were divided into 5 groups each and fed a basal diet supplemented with 0, 0.1, 1.0, 3.0 or 6.0 μg Se/g for 6 and 31 weeks, respectively. At the end of the experiments significantly higher concentrations of selenium were found in the groups fed 1.0, 3.0 and 6.0 μg Se/g diet compared to the control group. Correspondingly higher concentrations of selenium were found in egg samples. The increase in egg yolk selenium was much higher than in egg white. Significant correlations were found between the amounts of selenium added to the ration and the selenium concentrations in liver, kidney, breast muscle, egg white, yolk and homogenized egg. There were no differences in body weight gain and egg production between the groups. A possible positive contribution to animal and human health of selenium supplementation of animals’ diet above the required level is discussed. 相似文献
105.
The attracting effect of paralytic shell poison (PSP) on eight toxic snail species (Polinices didyma, Natica lineata, N. vitellus, Zeuxis sufflatus, Niotha clathrata, Oliva miniacea, O. mustelina, O. hirasei) and two non-toxic species (Pomacea canaliculata, Satsuma bairdi) was investigated. Eight toxic species were reported to contain tetrodotoxin, and three out of these contained minor PSP.
The minimum lethal dose of PSP in most toxic gastropods was estimated to be more than 150 MU PSP/20 g body weight, but in
non-toxic gastropods was less than 15 MU PSP/20 g body weight. After the attracting test, all toxic gastropods showed significant
positive linear relationship (Y=3.716X+0.363, r=0.8427) between comparative attracting variation and the toxicity reported. The relationship between PSP resistance ability
and the toxicity also had a positive correlation (Y=0.91X+210.090, r=0.6803). However, the non-toxic species showed a negative response. This indicates that PSP is an attractant for toxic snails. 相似文献
106.
河蟹溞状幼体培育期使用孔雀石绿杀灭聚缩虫的试验 总被引:1,自引:0,他引:1
孔雀石绿对河蟹(氵蚤)状幼体的48小时半数致死浓度Ⅰ期幼体为1.89ppm,V期幼体为7.45ppm。在河蟹工厂化育苗中如果发生聚缩虫感染,可采用孔雀石绿1ppm浓度全池泼洒、10~12小时内排出药液水、技入新水的方法杀灭聚缩虫,不会影响河蟹(氵蚤)状幼体的变态发育。 相似文献
107.
三种有毒物质对文蛤的毒性试验 总被引:4,自引:1,他引:4
在常温和静水条件下,用通常的生物毒性试验方法进行了H2S、Zn、NH3对文蛤的急性毒性试验,求出了它们对3.60 ̄3.74厘米体长文蛤的半致死浓度和安全浓度,为江苏沿海文蛤大批死亡的原因从侧面提供了分析的依据。 相似文献
108.
海蜇螅状幼体和碟状幼体窒息点和耗氧量的初步测定 总被引:5,自引:0,他引:5
在温度20±1℃和盐度22─24‰条件下,对海蜇螅状幼体和碟状幼体进行了窒息点和耗氧量的初步测定。结果表明:螅状幼体的窒息点低于0.10mg·L,直径3.4─10.2mm碟状幼体的窒息点为0.17─0.20mg·L。螅状幼体的个体耗氧量为2.93μg·d,耗氧率为2.66mg·g·h(干重):直径3.4、4.6和10.2mm碟状幼体的个体耗氧量分别为4.77、25.41和79.45μg·d,耗氧率分别为4.97、2.46和1.12mg·g·h(干重)。 相似文献
109.
110.