液相色谱-电喷雾质谱检测猪尿液中的蓖麻碱

试验建立了猪尿液中蓖麻碱的液相色谱-电喷雾质谱检测方法。尿液样本经聚合物填料固相萃取小柱(反相保留机制)净化,消除了基质的离子抑制效应,达到使用外标法定量蓖麻碱的目的。蓖麻碱的检测使用阳离子方式,以m/z165为定量离子,m/z138、84和82为佐证离子,做选择离子检测。在考察的浓度范围内(0.005～1.00μg/ml),方法有良好的线性(R2>0.99),检出限为6pg,定量限为15pg,添加回收率96.4%～101%,相对标准偏差3.74%～5.29%。动物试验显示,猪每千克体重饲喂0.2g的蓖麻粕后,在监测的5～20h内,其尿液中蓖麻碱保持相对较高的浓度。     

奶牛血液中蓖麻碱含量的HPLC检测

建立了血液中蓖麻碱残留量的高效液相色谱（HPLC）检测法。用三氯甲烷提取蓖麻碱，除去蛋白质和脂肪后，用HPLC法对其进行测定。采用Hypersil ODSC C18色谱柱（250mm×4．6mm，25μm），水-乙腈（9：1，V/V）为流动相，流速0．8mL／min，检测波长为220nm。结果显示，在0．26—5．2μg范围内，蓖麻碱峰面积与质量的线性关系良好，回归方程为y=1．57×10^4 x-4．93×10^5，r=0．999，RSD=3．82％。牛血中蓖麻碱平均回收率为72．1％，RSD为2．54％（n=5）。饲喂蓖麻粕的牛血液中蓖麻碱的含量为0．512μg／mL。     

夹心ELISA快速检测蓖麻粕中残留的蓖麻毒素

通过实验建立了蓖麻粕中残留蓖麻毒素的夹心ELISA检测方法(双抗原夹心法)。蓖麻粕样品经pH值7.4的磷酸盐缓冲液(PBS)提取,使蓖麻毒素充分溶出后可直接用于ELISA检测。在本文确定的实验条件下,蓖麻粕中杂质对蓖麻毒素的检测无显著影响;方法检出限小于2.5ng/ml,以蓖麻毒素浓度(5～80ng/ml)对数做校准曲线,R2=0.995。经高压灭菌锅0.1MPa处理1h的蓖麻粕中未检出蓖麻毒素,并以此作为蓖麻粕的阴性对照,对实际样品进行了测定。     

蚕粪中蓖麻碱的研究

在蚕粪的综合利用过程中曾分离得到蓖麻碱。本文报道应用纸色谱、红外光谱及紫外分光光度法鉴定及测定蚕粪中的蓖麻碱[524-40-3]。结果表明:用蓖麻叶饲养的蓖麻蚕粪中蓖麻碱的含量为0.964％(干物计),而用木薯叶饲养的蓖麻蚕粪及在家蚕粪中未发现蓖麻碱。蚕粪中的蓖麻碱实际上来源于饲料蓖麻叶。本文还讨论了蓖麻碱的应用前景以及蚕粪综合利用中可能存在的问题。     

脱毒蓖麻粕鸡猪有效能值及氨基酸利用率的研究

蓖麻粕是蓖麻籽榨油后的副产物 ,蛋白质含量较高 ,但由于含有毒蛋白、变应原、蓖麻碱等毒素 ,使其不能用于饲料中。蓖麻粕经过脱毒处理后其毒素含量降低 ,在畜禽饲料中可适量添加。为了解其有效能值、氨基酸含量及消化率 ,我们采样对脱毒蓖麻粕进行了鸡表观代谢能、猪表观消化能及氨基酸表观利用率的研究 ,为脱毒蓖麻粕在畜禽饲料中合理利用提供科学依据。1　材料和方法试验用脱毒蓖麻粕为采用加热及添加脱毒剂脱毒的蓖麻粕。选用体重 1 8～ 2 5ｋｇ的健康成年公鸡 ,体重 30～ 6 0ｋｇ的健康去势公猪 ,按《鸡饲料表观代谢能测定技术规程》…     

进口膨化去毒蓖麻粕——一种新型优质价廉的蛋白质饲料

(一) 膨化去毒蓖麻粕是蓖麻粕经筛粉去壳和膨化脱毒处理后的高蛋白优质饲料原料,由上海Castor饲料公司和北京旭农营养饲料有限公司生产和经销。 蓖麻粕是一种含多种毒素的高蛋白饲料原料,过去因未能解决原料的去毒问题,无法用于畜禽的配合饲料而被浪费掉。上海Castor饲料公司和北京旭农营养饲料有限公司对蓖麻粕的去毒问题进行了多年的研究,摸索出了一套行之有效的蓖麻粕去毒方法,去毒率达到90％以上。经猪鸡高用量饲喂试验,表明去毒后的蓖麻粕在规定的用量范围内可安全用于畜禽饲料。通过对蓖麻粕的营养学评定和饲养试验,表明蓖麻粕有以下几个方面的优点:     

蓖麻碱的分离鉴定及其含量测定方法的研究

蓖麻碱 (Ricinine) ,3-氰基 - 4-甲氧基 - 1 -甲基 - 2 -吡啶酮 ,分子式为C8H8N2 O2 ,分子量为1 6 4。因其分子中含氰基 ,毒性较大 ,对人可引起恶心、呕吐 ,严重时呼吸衰竭以致死亡 (林启寿 ,1 977)。蓖麻碱对家禽毒性较强 ,是一种导致甲状腺肿的潜在因子 (Pahuja ,1 978)。饲料中蓖麻碱含量超过0 .0 1 % ,抑制鸡的生长 ;含量超过 0 .1 %时 ,鸡麻痹中毒死亡 (Vohra等 ,1 976 ;史志诚等 ,1 996 )。雏鸡蓖麻碱的半数致死量LD50 为 1 1 .2 4 μg/g体重 ,其中毒症状为神经中枢麻痹 ,呼吸急促、困难 ,全身痉挛 ,步态不稳 ,最终倒地死亡 (闵建…     

蓖麻治疗畜病的小偏方

治猪羊的癫痫:红蓖麻根(红茎、红叶的蓖麻根)65g、鸡蛋2个,加醋适量煎煑1h候温。大猪一次将药与鸡蛋吃下,1次/d,连服数日。治蜂窝织炎:蓖麻籽150g,蒲公英100g,煎汁适量,大畜一次内服,再用鲜蓖麻叶2份,葱白1份,蜂蜜适量,捣膏涂患部,每日内服外涂各1~2次,可治蜂窝织炎漫肿无边。(李正飞)蓖麻治疗畜病的小偏方@李正飞     

饲喂脱毒蓖麻粕对肉鸡生产性能的影响

试验选用1日龄艾维因肉鸡雏500只,随机分成5个处理组。各试验组鸡的基础日粮组成和营养水平相同。试验各组在日粮中分别添加0、5%、10%、15%、20%的脱毒蓖麻粕。结果表明:日粮中添加5%和10%脱毒蓖麻粕能提高4～7周龄肉鸡增重,但差异不显著,而且Ⅱ组(10%)优于Ⅰ组(5%),高剂量的脱毒蓖麻粕(大于15%)对肉仔鸡的生长性能有明显的抑制作用。日粮中添加脱毒蓖麻粕各组与对照组相比,对肉仔鸡的屠宰率、胸肌率和腿肌率均无显著影响(P>0.05);在日粮中加入5%和10%的脱毒蓖麻粕后,肉鸡的采食量、健康状况良好,屠宰观察组织结构正常。     

免疫亲和-光化学柱后衍生高效液相色谱荧光法测定花生粕中黄曲霉毒素的研究

研究建立了光化学柱后衍生-高效液相色谱(HPLC)-荧光检测器测定花生粕中黄曲霉毒素B1、B2、G1和G2的方法。甲醇/水提取样品中黄曲霉毒素B1、B2、G1和G2,Afla-P黄曲霉毒素免疫亲和柱净化,经高效液相色谱分离后,由光化学柱后衍生,通过荧光检测器测定。结果表明:在优化条件下,黄曲霉毒素B1、B2、G1和G2的检出限分别为1.0、0.3、1.0μg/kg和0.3μg/kg,回收率为67.0%～117%,相对标准偏差(RSD)低于18.2%。该方法简便快速、灵敏度高、重现性好,满足饲料用花生粕中黄曲霉毒素检测的需要。     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein     

Avian brood parasitism — a growing research area in behavioral ecology (part Ⅱ)

正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in