Senecio jacobaea: deceiving beauty. Senecio jacobaea poisoning

In a cattle herd problems were noticed during 1.5 years, characterised by emaciation and loss of milk production with lower fat- and protein%, tenesmus, central nervous symptoms (aggression, circling and blindness), diarrhoea, eczema solare and death. Clinical, laboratory and post mortem examinations did not reveal a specific cause at first. An intoxication was suspected based on the clinical symptoms, the course of the disease in sick animals and severe liver cirrhosis found in a sudden death cow: The animals were fed grassilage derived from an air force base on which an overwhelming amount of tansy ragwort (Senecio jacobaea) was present. On subsequent microscopic examination of the livers of 11 slaughtered clinically healthy animals all of these showed fibrosis in varying extension. Cirrhosis and fibrosis of the liver and the clinical symptoms are all features of chronic pyrrolyzidine alkaloidosis. Tansy ragwort poisoning has not been diagnosed in the Netherlands for years. The rise in cases is due to more extensive use of land.     

Effects of dietary copper and molybdenum on tansy ragwort (Senecio jacobaea) toxicity in sheep

Dried tansy ragwort (Senecio jacobaea), which contains pyrrolizidine alkaloids (PA), was fed to sheep to determine whether PA consumption influenced liver Cu concentrations. Nine Polypay wether lambs were allotted to 3 groups according to the diets: control diet + 50 micrograms of Cu/g of feed (control + Cu); tansy ragwort (TR) diet + 50 micrograms of Cu/g of feed (TR + Cu); and TR diet + 50 micrograms of Cu/g of feed and 10 micrograms of Mo/g of feed (TR + Cu + Mo). Liver Cu concentrations were sharply increased (13-fold) after 8 weeks of feeding the diets, and then decreased slightly. There were no significant differences in concentrations of liver Cu among treatment groups. All lambs in the group fed TR + Cu + Mo died by the end of 23 weeks, with the usual signs of PA poisoning, including liver necrosis, hepatic megalocytosis, and biliary hyperplasia. The TR intake was about 2.7 to 3.0 kg/kg of their initial body weight. All lambs in the group fed the control + Cu diet survived. The results indicated that sheep fed TR do not preferentially accumulate liver Cu. There was an indication that dietary Mo increased susceptibility to TR intoxication.     

峨眉千里光对小鼠急性毒性及蓄积毒性研究

评价峨眉千里光毒性作用,采用机率单位法（Bliss法）和固定剂量蓄积系数法考察了峨眉千里光叶和全草水提物对小鼠经口急性毒性及蓄积毒性。急性毒性结果显示,不同剂量的峨眉千里光叶和全草水提物均能导致小鼠发生中毒和死亡,引起小鼠肺和肝脏损伤;叶水提物LD50为62.28 g/kg,95%可信限为52.68-73.65 g/kg;全草水提物LD50为81.65 g/kg,95%可信限为70.15-94.53 g/kg。蓄积毒性结果显示,峨眉千里光叶和全草的蓄积系数K〉5。结果表明,峨眉千里光叶和全草水提物对小鼠有急性毒性作用,叶的毒性比全草强,肺和肝脏为毒性靶器官;两种水提物均有轻度蓄积毒性。     

千里光抗菌有效部位化学成分及其急性毒性研究

用60％乙醇作溶剂制备千里先抗菌有效部位冻干粉（即千里光60％乙醇提取物）．分析其化学成分．并用改良寇氏法测定其对小鼠腹腔注射的急性半数致死量（LD50）。结果发现,千里光60％乙醇提取物合有生物碱、黄酮类化合物,但不含双稠吡咯啶生物碱;测得千里光60％乙醇提取物对小鼠腹腔注射的LD50为2206mg／kg,95％可信限为1867—2607mg／kg。表明千里光60％乙醇提取物属低毒性物质,并可保留千里光的有效成分生物碱和黄酮类化合物而排除其中的双稠吡略啶生物碱．进一步提高了千里光的安全性。     

Protective effects of antioxidants on bitterweed (Hymenoxys odorata DC) toxicity in sheep

Antidotal effects of the 2 antioxidants butylated hydroxyanisole (BHA) and ethoxyquin (EQ) were evaluated in bitterweed (Hymenoxys odorata DC) toxicosis in sheep. Bitteerweed contains a toxic sesquiterpene lactone, hymenoxon, the toxicity of which is reduced by cysteine. Both BHA and EQ are known to induce hepatic glutathione production in rodents. Treatment of sheep with EQ (2.5 g/sheep/day for 9 days before poisoning) gave significant protection from toxic doses of bitterweed, but the protective effect of BHA was insignificant. Of 6 sheep given EQ in the feed, 5 survived 7 doses of bitterweed (4 g/kg/day or higher for 7 days), whereas 5 of 7 controls and 4 of 7 sheep given feed with added BHA died. The added EQ in the feed decreased the serum alkaline phosphatase activity and total protein, albumin, and calcium concentrations. Seemingly, EQ is the first protective agent with field application potential for bitterweed toxicity.     

千里光的化学成分鉴定及体外抗菌试验

用分项试管预试法和圆形滤纸层析法对千里光的化学成分进行了检验;进行了千里光全草水煎剂及贡酮提取物的体外抗菌试验,结果表明,千里光全草含有黄酮及其甙类,酚性物质,鞣质,挥发油及生物碱等化学成分;千里光全草及其黄酮提取物对金黄色葡萄球菌,大肠埃希氏菌,肠炎沙门氏菌,炭疽杆菌,溶血性链球菌均有明显的抗菌作用。     

Pyrrolizidine alkaloidosis of cattle associated with Senecio lautu

Summary Serious incidents of pyrrolizidine alkaloidosis of cattle in 10 herds exposed to the Australian native plant, Senecio lautus (Asteraceae), were seen in central Queensland during 1988–1992. The deaths of 226 cattle were recorded. A mean of 8% of cattle died in affected groups (range 2 to 58%). Sickness and deaths usually occurred some months after access to S lautus. Typically, affected cattle lost body condition to the point of emaciation before dying and had persistent diarrhoea. Some animals developed abnormal behaviour and died after a shorter illness. Liver specimens from affected cattle in all herds contained lesions consistent with pyrrolizidine alkaloidosis. Thin layer chromatography of extracts of blood and liver samples from cattle from 5 herds detected pyrrolic metabolites. The identity of these was confirmed by mass spectroscopy on samples from one herd. Unseasonal autumn and winter rain after a dry summer appeared to favour growth of S lautus at the expense of other pasture species. A subsequent dry period promoted consumption of S lautus and was followed by a cluster of poisoning incidents.     

昆仑山小花棘豆生物碱提取及其对小鼠毒性试验

为进一步研究小花棘豆有毒成分提取方法及毒性作用,将昆仑山小花棘豆全草粉用不同浓度乙醇提取,以提取温度、超声时间和料液比等因素进行正交试验,考察对小花棘豆活性成分提取率的影响,并通过毒性试验对小花棘豆生物碱毒性进行评价。结果表明,提取温度、超声时间、料液比对小花棘豆生物碱提取率影响不显著。小花棘豆生物碱是其主要毒性成分,按1∶10浓度注射小花棘豆生物碱约3 mL可致小鼠死亡。     

千里光超微粉的镇痛机制研究

为研究中草药千里光（Senecio scandens Buch.-Ham）超微粉的镇痛机制,为千里光镇痛剂的开发利用提供参考依据,本研究以6周龄昆明小鼠为试验动物,制备千里光超微粉混悬液,设千里光超微粉高（360 mg/kg体重）、中（180 mg/kg体重）、低（90 mg/kg体重）剂量组,以灌胃方式连续给药7 d后进行后续相关试验,通过甲醛致痛模型和热浴甩尾法验证其镇痛作用并用以区分中枢镇痛和外周镇痛作用,通过纳洛酮颉颃试验、利血平颉颃试验及对小鼠血清和脑组织中五羟色胺（5-HT）和一氧化氮（NO）浓度的检测等方法来探究其中枢镇痛和外周镇痛机制。结果显示,千里光超微粉能提高甲醛致痛模型和热浴甩尾法中小鼠的痛阈值,且呈剂量-效应关系;纳洛酮和利血平分别作为阿片受体阻断剂和抗去甲肾上腺素能神经末梢药,可部分颉颃千里光超微粉的镇痛作用;千里光超微粉可显著提高脑组织5-HT的浓度,降低血清中5-HT的浓度（P<0.05）,但对于脑组织和血清中NO的浓度调节效果不明显。结果表明,千里光超微粉具有中枢性和外周性镇痛作用,其镇痛途径与阿片受体存在一定关系,可通过抑制囊泡膜对递质去甲肾上腺素（NE）的主动摄取过程而间接发挥镇痛作用;还可通过升高中枢NO和5-HT的浓度及降低外周NO和5-HT的浓度来发挥其镇痛作用,但对于NO的浓度调节效果不明显。     

藤本植物千里光的无性扦插繁殖技术

千里光(Senecio scandens)是一种药用价值和观赏价值较高的园林藤本植物。采用4因素3水平正交试验设计,以生根率、平均根长和平均生根数为扦插生根质量的指标,并构建生根质量指数,评价总的生根质量,研究NAA浓度、扦插基质、插穗类型和处理时间对千里光无性扦插繁殖生根的影响。结果表明,NAA浓度对生根质量指数影响的效果最大,处理时间次之,插穗类型居第3位,扦插基质影响最小。当NAA浓度为600 mg·L-1,扦插基质为红黄壤,插穗类型为带顶芽茎段,处理时间为1 h时,千里光无性扦插繁殖的生根质量最好。     

Toxicity of Riddell's groundsel (Senecio riddellii) to cattle

The toxicity of Riddell's groundsel (Senecio riddellii) fed to calves in gelatin capsules, by gavage, or mixed in their hay ration was determined. Dosages were varied according to the pyrrolizidine alkaloid (PA) content of the plant, and the calves' responses were measured by clinical signs, serum enzyme changes, survival time, and histopathologic changes. Calves fed S riddellii to provide 10 mg of PA/kg of body weight/day in capsules or by gavage for 20 consecutive days did not develop clinical signs of seneciosis and did not have meaningful serum enzyme changes. However, feedings of the plant that provided 15 to 20 mg of PA/kg/day or more (gavaged or fed in capsules for the same time period) resulted in high mortality. The Senecio plant mixed in calves' hay ration was eaten slowly and reluctantly and was tolerated at dosages greater than 20 mg/kg/day, emphasizing that the toxicity was dependent on the rate at which the dosage was consumed and that mortality was not necessarily dependent on the cumulative dosage. Because of its high PA content, S riddellii presents a great hazard to cattle managed under conditions where they can consume quantities of the plant in short periods of time.     

Echium vulgare and Senecio vulgaris poisoning in fighting bulls

An unusual case of poisoning by simultaneous ingestion of Echium vulgare L. and Senecio vulgaris L. in a herd of Spanish fighting bulls is described. Ten animals died from a herd of 700 in an area located in Sierra Norte, Seville (Constantina) in Spain. The interest of this case lies both in the breed affected (this is the first report on fighting bulls) and the lack of information about bovine poisoning by these plants in Spain. Animal samples were obtained from October to March. All the dead animals were 1 year old and had grazed at the farm. The diagnosis was made by determining the plant species and studying its distribution in the pastureland, and also by performing blood analysis of the sick animals in addition to an anatomopathological study of the carcasses. Tuberculosis, brucellosis, salmonellosis, IBR/BVD and also the presence of aflatoxins in the forage were all ruled out.     

The toxicity of phomopsin for sheep

Pure phomopsin was administered to young Merino x Border Leicester wethers by single subcutaneous (SC) and by single and multiple intraruminal (IR) injection. The toxicity after IR injection was influenced by the size of individual doses and the time over which the total dose was given. At high levels of ingestion the toxicity of phomopsin may be limited by absorption rates; with low daily doses the capacity to repair liver damage may be sufficient to prevent cumulative effects. By SC injection a single dose of 10 micrograms/kg approximated the LD50. By IR injection the overall clinical, biochemical and histological responses closest to these of this SC dose resulted from a single dose of 1,000 micrograms/kg. The same total dose administered at daily rates of 50 or 200 micrograms/kg was more toxic and killed all sheep. A single dose of 500 micrograms/kg caused significant liver damage, but no deaths. Single doses of 125 and 250 micrograms/kg and repeated daily doses of 12.5 micrograms/kg over 16 weeks caused no detectable tissue damage. Inappetence was the most sensitive indicator of phomopsin toxicity. About 10% of the sheep differed substantially from the rest of the flock in their susceptibility to phomopsin poisoning.     

Oxidative stress in the erythrocytes of cattle intoxicated with Senecio sp

BACKGROUND: Intoxication caused by Senecio sp is characterized by irreversible damage to liver cells and may be associated with oxidative stress. OBJECTIVES: The aim of this study was to evaluate the effects of intoxication by Senecio sp on lipoperoxidation, antioxidant defenses, and the osmotic resistance of erythrocytes in cattle. METHODS: Blood samples from 30 intoxicated animals (group 1) and 30 healthy animals (group 2) were analyzed. The diagnosis of poisoning by Senecio sp was based on histopathologic lesions verified through hepatic biopsy. The following biochemical parameters of oxidative stress in the erythrocytes were determined: thiobarbituric acid-reactive substances (TBARS), copper-zinc superoxide dismutase (CuZnSOD) activity, and nonprotein sulfhydryl (NPSH) groups. Erythrocyte osmotic fragility also was evaluated. RESULTS: TBARS concentration and CuZnSOD activity were significantly (P <.001) higher in group 1 when compared with group 2. The concentration of erythrocyte NPSH groups was significantly (P <.03) lower in group 1 when compared with group 2. Osmotic fragility was more pronounced in the erythrocytes of group 1 when compared with group 2 (P < .001). CONCLUSIONS: The results of this study indicate that poisoning by Senecio sp causes an increase in lipoperoxidation, oxidation of NPSH groups, and consequently, oxidative stress in bovine erythrocytes that may contribute to hemolysis. These findings may contribute to a better understanding of the mechanisms involved in cell damage in animals intoxicated by Senecio sp.     

The toxicity of Aristolochia bracteata in goats

Diarrhea, dyspnea, tympany, arching of the back, loss of condition, and loss of hair from the back were the prominent signs when Aristolochia bracteata was given orally to goats. The main lesions were hemorrhages in the lungs, heart, and kidneys, fatty change and congestion in the liver, mucoid abomasitis and enteritis and straw-colored fluid in serous cavities. An increase in aspartate aminotransferase activity, ammonia and urea concentrations and a decrease in the concentrations of total protein and magnesium were detected in detected in the serum.