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1.
本研究拟测定水解羽毛粉成分对现代瘦肉基因型猪的生长性能、胴体性状、养分消化率及粪中气味混合物的影响。选择 2 4 0头体重在 2 3.2± 1.3kg的猪 ,根据体重和性别进行 2× 6因子的随机区组设计 (每个处理 4圈 ,每圈 5头猪 )。因素包括 :1性别 (去势公猪或青年母猪 ) ;2日粮处理(分别添加 0 %、2 %、4 %、6 %、8%、10 %的水解羽毛粉 )。在 1～ 4试验阶段的日粮配合中 ,分别给以 1.0 0 %、0 .90 %、0 .75 %、0 .6 0 %的表观回肠可消化赖氨酸 ,其他氨基酸按理想氨基酸的比例供给 ,各阶段的有效磷和代谢能保持恒定。在生长性能上未发现羽毛粉成分和性别之间有显著的互作关系(P>0 .15 )。喂给 10 %羽毛粉的猪比喂 0、4 %、8%的猪体增重低 (P<0 .0 5 ) ,采食量比 0 ,4 %组低 (P<0 .0 5 )。随着羽毛粉添加水平的增加 ,超声波测定背膘厚有增加的趋势 (P =0 .12 )。喂给 10 %羽毛粉的猪日瘦肉增重比 0 %、2 %、4 %、8%的少 (P<0 .0 5 )。第 9周测定氮消化率发现 ,随羽毛粉添加量的增加氮的消化率呈二次减少 (P<0 .0 0 1) ,磷的消化率呈线性增加 (P<0 .0 2 ) ,且这种消化率的提高在去势公猪上比青年母猪更明显 (P<0 .0 5 )。从喂给 0 %、4 %、8%羽毛粉的猪群中取粪样分析气味混合物 ,发现喂给羽毛粉的猪粪其丁  相似文献   

2.
王怡丹  张营 《中国饲料》2023,1(10):78-81
文章旨在研究在育肥猪日粮中添加发酵豆粕对其生长性能及营养物质消化率的影响,试验选取60头三元杂交育肥猪,按照公母相同原则随机分为4组,每组15个重复,对照组饲喂基础日粮（玉米-豆粕型）,3个试验组分别按照5%、10%、15%发酵豆粕等量替代基础日粮中的豆粕,本次试验周期为60 d,试验结果表明,3个试验组末重均显著高于对照组（P <0.05）;5%发酵豆粕组、15%发酵豆粕组日平均增重显著高于对照组（P <0.05）,10%发酵豆粕组极显著高于对照组（P <0.01）;3组粗蛋白质、粗脂肪、粗纤维消化率显著或极显著高于对照组（P <0.05或P <0.01）,从营养物质消化率看,10%发酵豆粕组表现最佳。综合来看,用10%发酵豆粕替代育肥猪日粮中普通豆粕可帮助育肥猪更好地消化、吸收营养物质,提高育肥猪生长性能具有明显帮助。  相似文献   

3.
本研究分为2个试验,试验1旨在评定赖氨酸发酵蛋白粉在生长猪上的营养价值;试验2研究赖氨酸发酵蛋白粉等蛋白质替代豆粕对生长肥育猪生长、胴体性状和肉品质的影响.试验1:选用(25.0±1.1)kg杜×长×大三元杂交猪12头进行消化代谢试验,随机分为2组,每组6个重复,每个重复1头猪,分别饲喂无氮日粮和以赖氨酸发酵蛋白粉作为唯一蛋白质源的试验日粮,预试期4 d,正试期4 d.试验2:选用(41.7±3.9)kg杜×长×大三元杂交猪100头进行饲养试验,随机分为4组,每组5个重复,每个重复5头猪、.Ⅰ组为对照组,饲喂基础日粮;Ⅱ、Ⅲ和Ⅳ组分别为饲喂赖氨酸发酵蛋白粉等蛋白质替代10%、25%、50%豆粕的日粮,体重达100 kg左右结束.消化代谢试验结果表明:赖氨酸发酵蛋白粉消化能为12.85 MJ/kg,代谢能为11.80 MJ/kg.总氨基酸含量为47.38%,总氨基酸的回肠表观消化率、真消化率分别为66.95%和70.52%,赖氨酸和蛋氨酸的回肠表观消化率、真消化率分别为72.00%、75.14%和59.37%、64.52%.饲养试验结果表明:与对照组相比,在生长期和全期,Ⅳ组平均日增重显著降低(P＜0.05),料重比显著升高(P＜0.05);在肥育期,Ⅳ组平均日采食量显著增加(P＜0.05),料重比显著升高(P＜0.05),生长期和肥育期,Ⅳ组氮消化率、氮生物学效价显著降低(P＜0.05).Ⅳ组背膘厚显著增加(P＜0.05),眼肌面积和肌肉保水能力显著降低(P＜0.05).由此得出,与豆粕相比,赖氨酸发酵蛋白粉的粗蛋白质和脂肪含量较高,但非蛋白氮比例较大,氨基酸消化率较低.等蛋白质替代10%和25%豆粕对40～100 kg的生长肥育猪生产性能、胴体性状和肉品质均无影响,可作为饲粮中的新型蛋白质原料.  相似文献   

4.
张桂  田宝华 《养猪》1991,(3):2-4
发酵菜籽饼蛋白饲料,蛋白质含量高达45.38％,适口性好,用其取代饲料中鱼粉(3组)、豆粕(2组),或作为猪饲粮中唯一蛋白质饲料源(1组)饲喂瘦肉型生长肥育猪,与含鱼粉 豆粕的饲粮(4组)比较,日增重差异不显著(P>0.05)。即使日粮中配以高达27.5％的发酵菜籽饼蛋白饲料,猪只仍采食正常,无任何肉眼可见的中毒症状。经屠宰测定,1—3组胴体瘦肉率、背膘厚度、眼肌面积和后腿比例等指标,与4组比差异均不显著(P>0.05)。说明用发酵菜籽饼蛋白饲料部分或完全代替饲粮中的鱼粉、豆粕喂猪,有安全、等效、来源广、成本低的效果。  相似文献   

5.
试验采用2×3因子设计,在以普通豆粕为主的日粮Ⅰ和以去皮膨化豆粕为主的日粮Ⅱ中分别添加进口鱼粉0%、2.5%和5%,试验共6个处理组,各处理组日粮营养水平相同。将150头31日龄的断奶PIC仔猪(平均体重为6.09￣6.31kg)按体重相近的原则随机分为6个处理组,每处理组5个重复,每个重复5头仔猪,考察去皮膨化豆粕对仔猪生产性能和养分消化率的影响。结果表明,与普通豆粕相比,去皮膨化豆粕能改善仔猪的采食量(P=0.061),提高日增重5.1%,降低腹泻指数31.6%,改善对营养物质的消化率。鱼粉也影响仔猪的生产性能、营养物质消化率和腹泻指数,但与豆粕类型间存在显著的互作效应(P<0.05),普通豆粕日粮中添加鱼粉,仔猪的生产性能、营养物质消化率和腹泻程度均有改善,添加5%鱼粉组效果最好;而去皮膨化豆粕中添加鱼粉除能降低仔猪料肉比外,对仔猪采食量、日增重、营养物质消化率及腹泻指数均无改善作用。试验表明,利用去皮膨化豆粕配制断奶仔猪日粮完全可以不添加鱼粉,但结合生长性能和经济效益考虑,以去皮膨化豆粕日粮中添加2.5%进口鱼粉最好。  相似文献   

6.
试验旨在测定酶解羽毛粉的体外蛋白质消化率,同时研究酶解羽毛粉替代日粮中鱼粉对生长猪生产性能和蛋白质消化率的影响。体外试验采用胃蛋白酶-胰酶水解法对水解羽毛粉和酶解羽毛粉进行消化测定其蛋白质消化率。饲养试验选用135头体重相近的杜×长×大生长猪,随机分成3组,分别为对照组(3%秘鲁鱼粉组),处理Ⅰ和Ⅱ(酶解羽毛粉50%和100%替代秘鲁鱼粉)。结果表明:酶解羽毛粉体外蛋白质消化率比水解羽毛粉提高了15.38%(P<0.05)。处理组平均日增重和平均日采食量与对照组均无显著差异(P>0.05);饲料增重比及蛋白质消化率也与对照组差异不显著(P>0.05)。结合生产性能试验与经济效益分析,酶解羽毛粉100%等蛋白替代秘鲁鱼粉组为最佳,在生产实践中具备实用性和可行性。  相似文献   

7.
选用 32头体重为 60kg左右的三元杂交猪 (杜长大 ) ,随机分为对照组和试验组 ,对照组使用粗蛋白含量为 1 4 %的日粮 ,试验组使用粗蛋白含量为 1 2 % ,同时补加赖氨酸的日粮 ,以探讨使用低蛋白、补加赖氨酸日粮对肥育猪生产性能和胴体组成的影响。结果表明 :(1 )在肥育阶段使用低蛋白补加赖氨酸的日粮对于猪的日增重、日采食量、饲料转化率没有产生不利影响 ;(2 )两组猪血液中尿素氮和总蛋白的含量在统计上差异不显著 (P >0 0 5) ;(3)使用低蛋白补加赖氨酸日粮对于猪的胴体重、屠宰率、背膘厚和瘦肉率没有显著的影响 (P >0 0 5)。  相似文献   

8.
文章旨在研究断奶仔猪生长早期和后期采用不同结构日粮对其生长性能和营养物质表观消化率的影响。试验选择体重一致、21 d断奶的三元仔猪400头,随机分为5组,每组4个重复,每个重复20头。试验早期(21～42 d)采用5种日粮,处理1组(对照组)为玉米-豆粕-低乳糖-低鱼粉型,处理2组为膨化玉米-豆粕-高乳糖-高鱼粉型,处理3组为玉米-豆粕-高乳糖-高鱼粉型,处理4组为膨化玉米-豆粕-高乳糖-低鱼粉型,处理5组为膨化玉米-豆粕-低鱼粉-高乳糖型。试验后期(43～64 d),将试验早期的猪只按每2个重复(同一组)分别饲喂A和B两种日粮,A为膨化玉米-豆粕-鱼粉-乳清粉型,B为全谷物日粮型。结果 :各组对21～28 d、29～42 d及21～42 d仔猪的平均日增重、平均日采食量和料比均无显著影响(P 0.05)。与处理1组相比,其他各组显著降低了21～28 d、29～42 d及21～42 d仔猪的腹泻指数(P 0.05);试验早期和试验后期日粮对43～64 d仔猪各阶段的生长性能和腹泻指数均无显著影响(P 0.05)。试验早期,与处理1组相比,处理2、4和5组显著提高30 d仔猪有机物的表观消化率(P 0.05);试验后期两种日粮对50 d仔猪有机物、干物质、粗蛋白质及总能表观消化率均无显著差异(P 0.05)。结论 :在本试验条件下,与其他多样性日粮相比,21 d断奶仔猪饲喂玉米-豆粕、低乳糖和低鱼粉型日粮对生长性能无显著影响。断奶仔猪生长后期(43～64 d)日粮采用高蛋白谷物日粮可以促进生长性能。  相似文献   

9.
选用20kg左右的DLY生长猪64头,随机分为4个处理,每个处理4个重复,每个重复4头,分别饲喂基础日粮、添加2%、4%、6%水解羽毛粉（等蛋白替代豆粕）的日粮。结果表明,随着试验日粮中水解羽毛粉添加量的提高,试验猪的日采食量和日增重降低,而料肉比上升,并且6%处理组差异达到显著（P〈0.05）;各处理组的干物质表观消化率、蛋白质表观消化率和有机物表观消化率均差异不显著（P〉0.05）,而氮的表观生物学价值和净蛋白利用率随着水解羽毛粉添加量的提高明显降低,并且6%处理组的净蛋白利用率显著低于对照组（P〈0.05）和2%处理组（P〈0.05）;2%处理组的单位增重饲料成本较对照组降低0.20元/kg。  相似文献   

10.
采用机械活化法处理棕榈果柄和花生壳,并研究机械活化对棕榈果柄和花生壳消化性的影响及肥育猪的饲喂效果。以胃蛋白酶-胰蛋白酶二步法测定蛋白质体外消化率;以饲养试验观察肥育猪饲喂效果,试验选择60 kg左右的三元杂交猪(杜×长×大)150头,随机分成3组,每组5个重复,每个重复10头。对照组饲喂玉米-豆粕型基础日粮,试验1组和2组分别以10%机械活化棕榈果柄粉和花生壳粉等量替代基础日粮中玉米。试验结果表明,机械活化使棕榈果柄和花生壳的蛋白质体外消化率显著提高(P<0.05);饲养试验中,试验组日粮的表观消化率显著下降(P<0.05),日采食量和料肉比显著提高(P<0.05),但日增重无显著差异(P>0.05)。  相似文献   

11.
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。  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
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