不同狼尾草幼苗对镉胁迫的响应

采用温室盆栽试验,对4份野生狼尾草(Pennisetum alopecuroides)材料进行不同浓度镉(Cd)(0,10,20,50,100,200 mg·kg^-1)胁迫处理,通过对苗期生长指标、抗氧化酶(SOD,POD,CAT)活性、地上部与根的Cd²⁺积累量等指标的测定与分析,对4份材料的耐Cd性与Cd富集能力进行研究.结果表明:随着Cd²⁺浓度的升高,4份材料的存活率呈现逐渐降低的趋势,而株高、分蘖数、地上与地下生物量与对照相比无显著变化,SOD与CAT活性均呈现逐渐升高的趋势,POD活性则呈现无规律的波动性变化,材料P4耐Cd性最强.当Cd²⁺浓度为200 mg·kg^-1时,材料P1对Cd的吸收富集能力最强,在Cd污染土壤的修复上具有较好利用前景.     

高寒地区垂穗披碱草种质对低温胁迫的生理响应及其耐寒性评价

从青海、甘肃和四川境内的高原地区收集10份垂穗披碱草种质资源,在4 ℃低温下处理8、24和72 h,以25 ℃环境生长苗为对照,以材料对低温胁迫的响应为依据,评价种质耐寒性。结果表明,在低温胁迫下,参试材料叶片相对膜透性逐渐增大,阿坝县和若尔盖种质在低温胁迫8 h时叶片电导率高于对照143%和318%;叶绿素含量先降低后增加,但低温胁迫下含量均低于对照;参试材料中游离脯氨酸和可溶性糖含量逐渐增加,其中,阿坝种质游离脯氨酸和若尔盖种质可溶性糖含量增幅最大,在72 h时含量显著高于对照95%和207%;超氧化物歧化酶(SOD)和过氧化物酶(POD)活性先增强后减弱,玛曲和碌曲种质中SOD活性在24 h时增加最显著,分别高于对照147%和148%,刚察种质在低温胁迫下POD活性显著高于对照220%。运用隶属函数法综合评价10个种质材料苗期耐寒性发现,碌曲、卓尼县和阿坝县种质耐寒性最强;若尔盖种质耐寒性中等;临潭县、刚察县、夏河县、舟曲县、合作市和玛曲县种质耐寒性弱。     

高寒地区垂穗披碱草种质对低温胁迫的生理响应及其耐寒性评价

从青海、甘肃和四川境内的高原地区收集10份垂穗披碱草种质资源,在4℃低温下处理8、24和72 h,以25℃环境生长苗为对照,以材料对低温胁迫的响应为依据,评价种质耐寒性。结果表明,在低温胁迫下,参试材料叶片相对膜透性逐渐增大,阿坝县和若尔盖种质在低温胁迫8 h时叶片电导率高于对照143%和318%;叶绿素含量先降低后增加,但低温胁迫下含量均低于对照;参试材料中游离脯氨酸和可溶性糖含量逐渐增加,其中,阿坝种质游离脯氨酸和若尔盖种质可溶性糖含量增幅最大,在72 h时含量显著高于对照95%和207%;超氧化物歧化酶(SOD)和过氧化物酶(POD)活性先增强后减弱,玛曲和碌曲种质中SOD活性在24 h时增加最显著,分别高于对照147%和148%,刚察种质在低温胁迫下POD活性显著高于对照220%。运用隶属函数法综合评价10个种质材料苗期耐寒性发现,碌曲、卓尼县和阿坝县种质耐寒性最强;若尔盖种质耐寒性中等;临潭县、刚察县、夏河县、舟曲县、合作市和玛曲县种质耐寒性弱。     

披碱草与老芒麦苗期抗旱性综合评价

盆栽模拟土壤干旱条件,对采自我国不同生境的披碱草(Elymus dahuricus Turcz.)与老芒麦(Elymus sibiricus L.)10份野生种质材料苗期形态学和生理生化指标进行研究,旨在了解干旱胁迫下苗期抗旱特征及其抗旱能力,为披碱草属种质材料抗旱新品种选育、种质资源的开发利用提供理论依据。结果表明,随干旱胁迫日数增加,植株高度、叶面积、相对含水量和叶绿素都明显下降,而电导率、脯氨酸、SOD和POD都明显上升。经抗旱隶属度分析,10份材料抗旱性可分为3类:第一类为相对抗旱,包括SXD1、XJD2、NMD3、NMD4、GSD5、GSS1和JLS2共7份材料;第二类为中等抗旱,包括NMD6和SXS3共两份材料;第三类NMS4为相对易感。经相关分析筛选出对抗旱性影响显著的指标为:相对含水量、叶面积、相对电导率和叶绿素含量。     

6份川西北短芒披碱草种质苗期的抗旱性综合评价

为了探明来自川西北的6份短芒披碱草(Elymus breviaristatus)种质材料的苗期抗旱性差异,采用室内盆栽法对种质进行为期21d的干旱处理,分别于停止浇水第0、7、14和21天取植株叶片,研究了不同水分胁迫条件下各种质的相对含水量(RWC)、相对电导率(REC)、脯氨酸(Pro)含量、叶绿素(Chl)含量、丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性7个生理特征指标的变化,并采用隶属函数法对6份短芒披碱草种质材料的抗旱性进行综合评价。结果表明,干旱胁迫对不同抗旱短芒披碱草种质材料的各生理指标有显著的影响(P0.05),其各表型值与对照差异显著(P0.05),且各种质间差异显著(P0.05)。随着干旱胁迫时间的延长,6份短芒披碱草材料的相对含水量和叶绿素含量呈显著下降趋势(P0.05),而丙二醛含量、相对电导率、脯氨酸含量和POD活性表现出上升趋势,SOD活性呈现先上升后下降的趋势。由隶属函数分析7个生理指标得到供试材料苗期抗旱性强弱顺序依次为205176205133红10-5204290红6-5205104。     

铅胁迫对禾本科牧草生长、生理及Pb2+富集转运的影响

采用苗期盆栽试验,对14份禾本科牧草种质材料进行不同浓度(0,10,50,100,200,300 mg/kg)铅(Pb)胁迫处理,通过对株高、分蘖数、地上/地下生物量、脯氨酸含量、抗氧化酶(SOD、POD、CAT)活性、地上部与根中Pb²⁺含量等指标的测定与分析,探究Pb胁迫对禾草生长生理以及Pb²⁺富集转运的影响。结果表明,随着Pb浓度的增加,14份材料的株高、分蘖数、地上生物量均呈先上升后下降的趋势,地下生物量则逐渐降低,通过综合评价,来自土耳其的长穗冰草G₅具有较强的耐Pb性。随着Pb浓度的增加,地上部与根中Pb²⁺含量逐渐升高,富集系数逐渐降低,转移系数逐渐降低(披碱草G₇与G₈除外),根中Pb²⁺含量显著高于地上部,为Pb²⁺的主要富集器官,披碱草地上部Pb²⁺含量高于其他材料,具有较强的Pb富集转运能力。7份材料的生理指标测定结果表明,随着Pb浓度的增加,7份材料的脯氨酸含量逐渐上升,CAT活性逐渐下降,POD和SOD活性则呈先上升后下降的趋势。     

59份苜蓿种质材料苗期耐盐性评价及耐盐指标筛选

为了解不同苜蓿种质材料耐盐程度和筛选苜蓿苗期耐盐性评价指标,本研究采用盆栽法对59份苜蓿种质材料苗期进行200 mmol·L^-1 NaCl盐溶液胁迫处理,测定了与苜蓿耐盐性相关的12个生长指标和叶绿素荧光指标,并利用综合评价、相关性分析、灰色关联和聚类分析等方法对其苗期耐盐性进行评价及耐盐指标筛选。结果表明：地上生物量、地下生物量、根冠比、叶面积、叶长、茎粗、叶宽、株高和SPAD（Soil and plant analyzer develotrnent,SPAD,代表相对叶绿素含量）在不同种质材料间变异大,对盐胁迫反应敏感。用加权隶属函数法得到的耐盐性综合度量值（D值）对59份苜蓿材料苗期的耐盐性进行综合评价,基于D值进行聚类分析,可将59份材料划分为5类：第I类有16份种质材料,D值为0.384,属中等耐盐材料;第II类有13份种质材料,D值为0.465,属强耐盐材料;第III类有4份种质材料,D值为0.647,属极强耐盐材料;第IV类有8份种质材料,D值为0.229,属极弱耐盐材料;第V类有18份种质材料,D值为0.305,属弱耐盐材料。综合筛选出耐盐性极强的材料有‘美11’、‘中苜1号’、‘爱开夏’和‘中苜3号’,耐盐性极弱的材料有‘北方SLT’、‘康赛’、‘WL903’、‘WL440HQ’、‘杂6’、‘Natawwakaba’、‘罗默’和‘甘农3号’。通过相关性分析和灰色关联,筛选出叶面积、叶绿素荧光、SPAD和根冠比可作为苜蓿苗期耐盐性鉴定指标。本研究可为耐盐苜蓿新品种选育及利用提供理论依据。     

西藏野生垂穗披碱草苗期抗旱性研究

室内盆栽模拟土壤干旱胁迫,对不同海拔来源的3份野生垂穗披碱草(Elymus nutants Griseb.)苗期生理生化指标进行了研究。试验结果表明,随着干旱胁迫日数的增加,叶片Chla和Chlb明显下降,而MDA、Pr和CAT明显上升;当干旱胁迫到14d后,叶片MDA、Pr和CAT则出现了下降趋势。运用隶属函数法综合分析初步判定苗期抗旱性强弱顺序为Ⅲ号材料Ⅱ号材料Ⅰ号材料。     

藏沙蒿种质材料苗期抗旱性综合评价

为评价藏沙蒿(Artemisia wellbyi)野生种质材料苗期抗旱性，以采自我国西藏地区不同生境的13份藏沙蒿种质材料为研究对象，采用盆栽控水法模拟土壤干旱条件，设置未胁迫CK、中度和重度3个干旱胁迫处理，研究干旱胁迫对藏沙蒿材料苗期生长和生理生化特性的影响，采用主成分分析和隶属函数相结合的方法对其抗旱性进行综合评价。结果表明：干旱胁迫下，供试藏沙蒿材料的相对电导率(Relative conductivity, REC)、丙二醛(Malondialdehyde, MDA)含量、过氧化物酶(Peroxidase, POD)、超氧化物歧化酶(Superoxide dismutase, SOD)以及过氧化氢酶(Catalase, CAT)活性和脯氨酸(Proline, Pro)、可溶性糖(Soluble sugar, SS)含量均增加，可溶性蛋白(Soluble protein, SP)含量不同材料之间存在一定差异性(P<0.05);综合评价认为11号材料抗旱性最强，10号和3号次之，6号材料抗旱性最弱；建议11,10和3号藏沙蒿材料作为西藏高寒荒漠草地生态恢复和育种研究的首选材料...     

百脉根种质苗期抗旱性鉴定及综合评价

采用土培法对21份百脉根种质材料进行了苗期抗旱性评价。结果表明：在干旱胁迫下,明显抑制百脉根的正常生长,地上生物量、地下生物量、株高、分枝数明显减小,根冠比明显增加;渗透调节物质丙二醛（MDA）、脯氨酸（PR0）、可溶性糖、可溶性蛋白的含量明显增加,过氧化物酶（POD）、过氧化氢酶（CAT）、超氧化物歧化酶（SOD）活...     

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.     

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.     

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.     

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.     

A brief history of the prevention of infectious diseases by immunisations

Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.