牛轮状病毒重组株的血清学和基因型特性

从母牛接种过Ａ组ＢＲＶ株ＮＣＤＶ－Ｌｉｎｃｏｌｎ（Ｐ１：Ｇ６）苗的两个吡邻牛场分离到两株牛轮状病毒（ＢＲＶ），编号为ＮＳ－１和ＮＳ－２，Ｎｏｒｔｈｅｒｎ－ｂｌｏｔｔｉｎｇ试验表明，ＮＳ－１和ＮＳ－２有相的的Ａ组ＲＮＡ电泳模式，而且全部基因片段同源，体外中和试验表明，ＮＳ－１株病毒能被Ｇ６特异性单克隆抗体（ＭｃＡｓ）和抗ＢＲＶＢ６４１株（Ｐ５：Ｇ６）豚鼠高免血清（ＧＰＡＳ）中和，但不被Ｇ１０特异性Ｍ     

马源轮状病毒血清3型引起的马驹腹泻

１９８７年３－７月，在１６８例马驹腹泻病例中观察到８９例（５３％）由轮状病一道因清３型引起，从６２病例粪便中共分离到５１株ＲＶ，分离株（ＣＨ－３）具有独特的毒ＲＮＡ电泳型且不同于该农场广泛流行的其他病毒株，用抗人和动物的ＲＶ血清１－１２型抗血清分别与ＣＨ－３病毒进行中和试验均呈阴性，但Ｃ－３病毒株双股ＲＮＡ能与马源ＲＶ血清３型株进行探针杂交。     

鸭瘟、鸭霍乱紧急防治措施研究

对鸭瘟、鸭霍乱紧急防治措施作了系列研究，结果表明：鸭瘟、鸭霍乱多价卵黄抗体对１００个ＬＤ５０鸭瘟强毒和８．３个Ｃ４８－１强毒菌的攻击具有１００％（８／８只）中和能力，对鸭瘟强毒（１００个ＬＤ５０）和Ｃ４８－１（８．３个）攻毒后５～６小时注射４倍稀释卵黄抗体２．０ｍｌ／只，具有１００％（６／６只）保护（口服有８３．３％保护）；分别以正常量和５倍量的鸭瘟弱毒苗免疫２月龄鸭，５～６小时后攻鸭瘟强毒，结果无一存活，鸭瘟弱毒苗和鸭瘟－禽霍乱二联活苗免疫后３天，对１００个ＬＤ５０鸭瘟强毒攻击获５０％（３／６）保护，７天获８３．３％（５／６）保护。Ａ群菌苗免疫后６天对Ｃ４８－１攻击获６６．７％（４／６只）保护，１２天获１００％保护。鸭瘟－禽霍乱二联活苗免疫后３天对Ｃ４８－１攻击获３３．３％（２／６）保护，７天获８３．３％保护；巴氏杆菌卵黄抗体和血清抗体能明显抑制巴氏杆菌生长并有溶菌现象出现；复方痢菌净、喹乙醇、庆大霉素、链霉素和四环素对多杀巴氏杆菌高度敏感（１７～４１ｍｍ）。     

RT-PCR检测禽传染性支气管炎病毒

用２对已发表的引物和１对自行设计的引物对同一禽传染性支气管炎病毒（ＩＢＶ）Ｈ１２０株进行ＲＴ－ＰＣＲ,分别获得了Ｓ１基因上与引物设计相一致的１７２０、２２８、６０２ｂｐ的扩增片段。用自行设计的引物对７个毒株（Ｈ１２０、Ｈ５２、Ｍ４１、Ｃｏｎｎ、Ｇｒａｙ、Ｔ、Ｈｏｌｔｅ）和５个分离株（宜毒、上毒、云毒、ＨＫ、１１８）的含毒尿囊液或纯化病毒进行ＲＴ－ＰＣＲ,结果除Ｈｏｌｔｅ株和２个分离株（宜毒、云毒）外,其余均成功地扩增出６００ｂｐ的片段。用１．７、０．２、０．６ｋｂ３对引物对６个ＩＢＶ毒株和６个分离株的含毒尿囊液在相同和不同条件下进行ＲＴ－ＰＣＲ,结果３对引物分别扩增出３、５、９株ＩＢＶ,同时可将不同血清型的１２个ＩＢＶ株分成６种基因型。将ＩＢＶ分离株ＨＫ与标准株Ｍ４１经ＰＣＲ扩增、ＨａｅⅢ和Ｈｉｎｄ酶切、ＲＦＬＰ分析,表明属同一马萨诸塞血清型。３株ＩＢＶ（Ｈ１２０,ＨＫ,Ｍ４１）在鸡胚中繁殖,ＰＣＲ最早检出的时间为２０～２４ｈ。ＲＴ－ＰＣＲ提供了直接从尿囊液和感染鸡组织中快速检测病毒的新方法。     

犬瘟热疫苗弱毒的复壮与免疫试验

将一株犬瘟热疫苗株病毒通过Ｖｅｒｏ细胞２０代（ＣＤＶ／Ｒ－２０）后又通过敏感犬的腹腔巨噬细胞，获得一株免疫原性更高的弱毒株（ＣＤＶ／Ｒ－２０／８）。接种同样剂量１０４ＴＣＩＤ５０的ＣＤＶ／Ｒ－２０／８和ＣＤＶ／Ｒ－２０的犬，产生出血清中和（ＳＮ）抗体价的几何平均数分别为１：５４和１：２６。前者为后者的２倍多。接种１０５ＴＣＩＤ５０的ＣＤＶ／Ｒ－２０／８能完全保护犬（１０／１０）抵抗ＣＤＶ强毒的攻击，接种１０４ＴＣＩＤ５０的保护９／１０犬，而对照犬５只全部发病，其中４只死亡。犬体内ＳＮ价可持续一年之久。冻干培养物在４和－３０℃中可分别保存９个月和１２个月而效力不减。     

逆转录—聚合酶链反应（RT—PCR）检测轮状病毒

为了给轮状病毒感染的诊断和流行病学研究提供更为敏感和可靠的手段,选取Ａ组轮状病毒ＶＰ７基因上的２段高度保守序列作为引物,在优化逆转录－聚合酶链反应（ＲＴ－ＰＣＲ）条件的基础上,建立了检测轮状病毒的ＲＴ－ＰＣＲ方法。通过对比试验,确定了ＰＣＲ的最优模式：９４℃变性１ｍｉｎ→５５℃退火１ｍｉｎ→７２℃延伸２ｍｉｎ,３０个循环后再在７２℃下延伸１０ｍｉｎ。用此模式进行了ＲＴ－ＰＣＲ的特异性和敏感性试验。检测的６株轮状病毒分离株（牛ＨＮ－７、ＢＲＶ００７、ＢＲＶ０１４、ＢＲＶ６５５５、猪Ｌｉ９９、Ｎａｎ８６）及２株参考株（牛ＮＣＤＶ、猴ＳＡ１１）,都能扩增出唯一的３４２ｂｐ的目的条带;对猪流行性腹泻病毒（ＰＥＤＶ）及传染性胃肠炎病毒（ＴＧＥＶ）感染猪的粪样、正常ＭＡ１０４细胞检测结果均呈阴性;检测的敏感度可达１ｐｇ水平。对４０份猪、牛、兔的腹泻粪样检测,３０份呈阳性,而用作平行对照的夹心ＥＬＩＳＡ法检测,有２５份呈阳性,两者符合率为８７．５％。两法检测不符的５份粪样的ＰＣＲ扩增产物,用地高辛标记探针进行了斑点杂交,结果均呈阳性,表明ＲＴ－ＰＣＲ法比ＥＬＩＳＡ法敏感性高。     

表达马立克氏病病毒CV1988／Rispens糖蛋白B重组鸡痘病毒的免？…

用表达马立克氏病病毒（ＭＤＶ（Ｉ型疫苗株ＣＶ１９８８／Ｒｉｓｐｅｎｓ糖蛋白Ｂ（ｇＢ）基因的重组鸡痘病毒（ｒＦ－ＰＶ－ｇＢ／Ｒ）和鸡痘病毒（ＦＰＶ）疫苗株２８２Ｅ４免疫１日龄不同品种的鸡,来评价２种病毒株的安全性及免疫母源抗体的商品是我毒性,而对无毒源抗体的ＳＰＦ鸡的毒性则不同。斑点杂交和Ｓｏｕｔｈｅｒｎ杂交产,ｆＦＰＶ－ｇＢ／Ｒ中无氨苄青霉素的抗性基因。     

抗鸡传染性法氏囊病病毒单克隆抗体中和株的建立

将纯化的鸡传染性法氏囊病病毒（ＩＢＤＶ）组织毒免疫的ＢＡＬＢ／ｃ鼠脾细胞与ＳＰ２／０骨髓瘤细胞融合，用ＥＬＩＳＡ，病毒中和试验检测分泌抗体，获得了６株稳定分泌抗ＩＢＤＶ单隆抗体的杂交瘤细胞，命名为ＮＩＢ－１，ＮＩＢ－２，ＮＩＢ－３，ＮＩＢ－４，ＮＩＢ－５，ＮＩＢ－６；６株ＭＣＡｂ均具ＥＬＩＳＡ特性和免疫沉淀特性，亚类鉴定表明，前４株属于ＩｇＧ２ａ，后２株属于ＩｇＧ１。杂交瘤细胞冻存６个月后复苏，均     

微量PCR检测鸡马立克氏病病毒早期感染

为了建立一种监测鸡群马立克氏病病毒（ＭＤＶ）早期感染的微量ＰＣＲ方法,根据血清Ⅰ型马立克氏病病毒（ＭＤＶ１）基因组ＢａｍＨＩ－Ｌ片段的核酸序列设计了１对寡核苷酸引物,用含０．３ＵＴａｑ酶的１０μＬ反应体系分别扩增了ＭＤＶ１型（京－１株、ＭＤ１１／７５ｃ株）、ＭＤＶ２型（ＳＢ－１株）和ＨＶＴ（ＦＣ－１２６株）的核酸,并用京－１株感染细胞ＤＮＡ作了敏感性试验。结果显示,该引物对ＭＤＶ１型病毒特异,京－１株和ＭＤ１１／７５ｃ株都扩增到４２５ｂｐ的核酸条带,而ＳＢ－１株、ＦＣ－１２６株和正常ＣＥＦ细胞的ＤＮＡ都没有得到任何条带;敏感性试验结果表明,微量ＰＣＲ能够检测到０．１ｐｇ的京－１株感染细胞ＤＮＡ;对京－１株感染鸡,在接种后第５天就能在血液细胞中检测到ＭＤＶＤＮＡ。微量ＰＣＲ可望成为监测鸡群ＭＤＶ早期感染的一种快速、有效的方法。     

犬瘟热弱毒疫苗免疫犬抗体消长规律及影响因素

应用犬瘟热病毒（ＣＤＶ）血清中和试验，对从日本引进的犬瘟热弱毒疫苗免疫犬的血清中和抗体效价进行了检测，探讨了免疫剂量、免疫程序和犬的年龄对抗体效价的影响。结果表明，试验犬于第１次免疫后１４ｄ左右产生１∶９以上的血清中和抗体，随后抗体水平迅速升高，３５ｄ时７８．３８％的免疫犬抗体效价超过１∶１００，６０ｄ达到高峰，６个月试验结束时，血清中和抗体效价仍维持在１∶１００以上。该犬瘟热弱毒疫苗的最低免疫剂量为１０３．０ＴＣＩＤ５０，以２周或３周间隔连续免疫３次均可使免疫犬获得完全保护。     

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.     

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.     

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.     

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.     

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.     

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.