菊科植物茼蒿有效成分提取工艺条件筛选

试验采用回流提取法,以乙醇作为提取溶剂,按4因素3水平设计正交试验,筛选菊科植物茼蒿有效成分的最佳提取工艺条件。通过分析极差R值表明,乙醇浓度、萃取温度、萃取时间及固液比对得率影响的主次顺序是：乙醇浓度〉萃取温度〉固液比〉萃取时间。最终确定菊科植物茼蒿有效成分最佳提取工艺条件是：乙醇浓度为55%,萃取温度为95℃,萃取时间为2h,固液比为1∶8时得率最高。     

响应面法优化超临界CO2萃取红豆草缩合单宁工艺技术研究

为研究超临界流体技术制备红豆草缩合单宁工艺技术条件，首先以单因素试验进行范围筛选，再应用BBD试验设计进行工艺优化。结果表明：缩合单宁最佳提取工艺为：萃取压力34.8 MPa、萃取时间123.0 min、萃取温度40.3 ℃、萃取夹带剂流量2.0 mL/min、夹带剂50%乙酸乙酯。在此条件下，红豆草缩合单宁提取率达到89.23%，接近理论值。综上，超临界CO2萃取技术可以用于红豆草缩合单宁的提取。 [关键词] 超临界CO2萃取|红豆草|缩合单宁|响应面|工艺优化     

菊科植物茼蒿有效成分提取工艺条件筛选

试验采用回流提取法,以乙醇作为提取溶剂,按4因素3水平设计正交试验,筛选菊科植物茼蒿有效成分的最佳提取工艺条件.通过分析极差R值表明,乙醇浓度、萃取温度、萃取时间及固液比对得率影响的主次顺序是:乙醇浓度＞萃取温度＞固液比＞萃取时间.最终确定菊科植物茼蒿有效成分最佳提取工艺条件是:乙醇浓度为55％,萃取温度为95℃,萃取时间为2h,固液比为1∶8时得率最高.     

恩拉霉素提取工艺研究

为优化恩拉霉素提取工艺,以70%甲醇溶液为提取剂,提取恩拉霉素,经过浓缩、脱色、结晶、重结晶,制备高含量恩拉霉素产品。得到最佳提取工艺条件是：浸提pH3.5~4.0,浸提温度30 ℃,三次浸提时间1 h,一次浸提料液比1∶7,二次浸提料液比1∶3,三次浸提料液比1∶3,活性炭用量是浓缩液体积的1.0%~1.5%,粗精粉重结晶得到纯品,含量97%。     

甘草渣中木质素的超临界CO_2脱除工艺研究

为了研究并优化利用超临界CO_2对甘草渣木质素的萃取脱除工艺条件,试验采用超临界CO_2萃取技术,研究不同萃取条件(温度、压力、时间和料液比)对甘草渣中木质素脱除效果的影响,并设计正交试验以确定最优条件。结果表明:在温度为180℃、压力为20 MPa、时间为40 min、料液比为1∶0.4的条件下,甘草渣中木质素脱除率可达最大,为75.918 0%。     

盐酸咪唑苯脲复乳制备条件的优化研究

为了优化盐酸咪唑苯脲复乳制剂的配方和乳化条件,首先通过单因素筛选试验,确定最佳油相和乳化剂的种类、浓度及油水比例、乳化条件确定初乳制备条件;再通过选择不同外水相乳化剂、外水相与初乳体积比、内水相稳定剂与用量以及乳化条件,确定复乳制备条件。结果表明,选择白油作为油相、10%的OP-10为乳化剂、油相和水相比例7∶3,乳化温度为40℃,乳化时间为3 min,乳化速度为10000 rpm时为制备乳剂的最佳条件;选择7%浓度的外水相乳化剂,外水相与初乳体积比为5∶5,选择10%明胶液稳定剂,采用25℃、1 min、4000 rpm的乳化条件制备的复乳制剂效果最佳,研究初步获得了盐酸咪唑苯脲复乳制剂配方和乳化条件。     

血满草多糖提取工艺优化及其单糖组分分析

为了优化血满草多糖的提取工艺并分析其单糖组成,试验考察了提取温度、提取时间、溶剂用量和提取次数对血满草多糖提取率的影响,以单因素试验结果为基础,使用响应面法对血满草多糖的提取工艺进行优化,模拟得到二次多项式回归模型,并采用气相色谱-质谱联用技术分析其单糖组成。结果表明:血满草多糖的最佳提取工艺为提取温度89.72℃,提取时间114.15 min,溶剂用量26.40 mL/g,提取4.28次。考虑到实际操作,最终将最优提取参数确定为提取温度89℃,提取时间114 min,溶剂用量26 mL/g,提取4次,此时的多糖提取率预测值为2.688 5%。经验证试验,血满草多糖的实际提取率可达(2.611 3±0.027 7)%,与模型预测值接近,两者相对误差为2.96%。血满草多糖主要由鼠李糖、阿拉伯糖、甘露糖、葡萄糖、半乳糖构成,摩尔比为1.00∶2.43∶0.51∶4.96∶1.82。说明优化工艺合理,得到的回归模型可真实反映提取条件对血满草多糖提取率的影响,并明确了血满草多糖的单糖组分。     

鲍鱼脏器蛋白脱色条件的研究

笔者采用单因素和正交试验的方法,利用食用酒精对鲍鱼脏器蛋白液实施脱色处理,考察了酒精用量、pH值、温度和时间等因素对色差和肽损失率(LP)的影响。结果表明,酒精用量1∶1、pH值为8、脱色温度35℃、吸附时间20 min,此时鲍鱼内脏蛋白液脱色效果最为明显,色差为13.3%,肽损失率为48%。     

超临界CO_2萃取金丝桃素工艺的响应面优化研究

在实验条件下确立了贯叶连翘中金丝桃素超临界CO2萃取的最佳工艺条件。在单因素实验基础上,采用响应面分析法,对影响超临界萃取物中金丝桃素含量的主要因素包括萃取温度、萃取压力与夹带剂浓度(乙醇体积分数)进行优化,建立了影响因素与响应值(金丝桃素含量)之间的函数关系。根据回归方程寻优得出最佳工艺条件。最佳工艺条件为以体积分数78.6%的乙醇作动态夹带剂,萃取温度50.3℃、萃取压力25.29 MPa,在此条件下,设定乙醇流速0.5 mL.min-1、CO2流速2 L.min-1,萃取2 h,超临界萃取物中金丝桃素含量平均达到1.102%,大大高于传统提取方法(碱醇溶液提取),适用于贯叶连翘中金丝桃素的提取。     

碱处理法降解甘草渣中木质素、纤维素和半纤维素工艺研究

为了确定碱处理法降解甘草渣中木质素、纤维素和半纤维素的最优工艺条件,以促进甘草渣饲料化研究进程,试验以氢氧化钠(Na OH)和尿素为裂解剂,通过单因素试验和正交试验研究了处理时间、裂解剂用量、料液比和反应温度四种条件对甘草渣中木质素、纤维素和半纤维素的降解效果。结果表明:在处理时间为3 d、裂解剂比例(Na OH与尿素比例)为5∶5、料液比为1∶12、反应温度为45℃的条件下木质素降解率可达23. 076 9%,纤维素降解率可达41. 059 3%,半纤维素降解率可达75. 176 6%,在此条件下糖含量增加了1 918. 37倍。说明采用碱处理法处理甘草渣中木质素、纤维素和半纤维素具有较高的降解率,同时可有效提高糖含量。     

白术、微米白术和白术多糖对断奶仔猪生长性能和肠道形态及微生态区系的影响

试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。     

Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia

Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.     

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.     

Y‐chromosomal variation of local goat breeds of Turkey close to the domestication centre

Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.     

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.     

Feline intracranial neoplasia: retrospective review of 160 cases (1985-2001)

The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.     

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.