山羊瘤胃给饲蛋氨酸和拉沙里菌素对血液指标的影响

采用3只装有永久性瘤胃瘘管的萨能母山羊为试验动物．试验分为4期，每期6d。每期为一个处理。对照组：基础日粮；处理Ⅰ：基础日粮＋15g蛋氨酸；处理Ⅱ：基础日粮＋15g蛋氨酸＋0．15g拉沙里菌素；处理Ⅱ：基础日粮＋15g蛋氨酸＋0．20g拉沙里菌素。每期的最后一天为血样的采样日，采样日的采样时间点为3个，即当日早晨饲喂前（0h）、饲喂后2h和5h。血样经处理后．测定样本中血浆游离蛋氨酸（PFM）的含量和有关酶的活性。试验结果表明：不同处理之间，在0h处理Ⅲ的谷氨酸脱氢酶（GLDH）、γ-谷氨酰转移酶（GGT）活性显著高于对照组（P＜0．05），谷草转氨酶（GOT）极显著低于对照组（P＜0．01），谷丙转氨酶（GPT）活性极显著高于对照组（P〈0．01），处理ⅡGOT活性极显著低于对照组和处理Ⅰ（P〈0．01）；在2h处理ⅡGGT活性显著低于处理Ⅱ（P＜0．05），极显著低于处理Ⅰ（P〈0．01），处理ⅢGPT活性显著高于处理Ⅱ（P〈0．05），极显著高于对照组和处理Ⅰ（P＜0．01）；在5h处理IGGT活性显著高于处理Ⅱ（P＜0．05），处理ⅢGPT活性极显著高于对照组（P〈0．01），处理Ⅰ的PFM水平在0、2、5h均极显著高于对照组、处理Ⅱ和处理Ⅱ（P〈0．01）；不同处理内，处理Ⅰ的0hGGT活性显著低于2、5h（P〈0．05）。5h的PFM水平显著高于0、2h（P〈0．05），处理Ⅲ的5hGGT活性低于0h（P〈0．05）。     

过瘤胃保护氨基酸和小肽对体外瘤胃发酵指标的影响

用3头装有永久性瘤胃瘘管的奶牛,在晨饲前2h采瘤胃液,用于体外批次培养。试验Ⅰ组、Ⅱ组、Ⅲ组日粮中分别添加脂肪包被蛋氨酸和赖氨酸、脂肪包被的小肽、用甲醛处理的蛋氨酸和赖氨酸。试验结果表明,各时间点的体外产气量没有显著差异,各试验组产气量均低于对照组;试验Ⅰ组6h时间点和试验Ⅱ组24h时间点培养液中瘤胃细菌氮产量显著提高（P〈0．01）,6h、12h时间点NH3-N产量高于对照组,24h时表现有逐渐下降的趋势。     

体外培养条件下氨基酸对瘤胃蛋白质降解菌生长限制性的影响

本试验旨在研究体外培养条件下氨基酸对瘤胃蛋白质降解菌[嗜淀粉瘤胃杆菌(R.amylophilus)、溶纤维丁酸弧菌(B.fibrisolvens)和柄瘤胃普雷沃氏菌(P.ruminicola)]生长限制性的影响.以4头安装永久性瘤胃瘘管的徐淮山羊为瘤胃液供体,采用人工模拟山羊瘤胃发酵装置进行培养.通过特定氨基酸缺省的方法,设定5个组:全量氨基酸组、蛋氨酸缺省组、赖氨酸缺省组、支链氨基酸缺省组以及芳香族氨基酸缺省组.结果表明:特定氨基酸缺省对嗜淀粉瘤胃杆菌、溶纤维丁酸弧菌和栖瘤胃普雷沃氏菌的生长限制性作用有所差异.特定氨基酸的缺省对嗜淀粉瘤胃杆菌、溶纤维丁酸弧菌和栖瘤胃普雷沃氏蒲的生长限制性作用(相对于全量氨基酸组)排序分别为芳香族氨基酸>赖氨酸>支链氨基酸>蛋氨酸;赖氨酸>芳香族氨基酸>支链氨基酸>蛋氮酸;支链氨基酸>芳香族氨基酸>蛋氨酸>赖氨酸.由此得出,在体外培养条件下,氨基酸缺省将影响瘤胃蛋白质降解蔚的生长.     

中链脂肪酸对体外发酵甲烷产量的影响

利用人工瘤胃体外产气法研究不同精粗比（0：1和1：1）日粮类型时中链脂肪酸对甲烷产量的影响。结果显示，体外培养24h，添加脂肪酸对甲烷产量的抑制作用不受日粮类型的影响（P〉0．05）；与不添加酸的对照相比，添加50mg未酯化月桂酸（C12,0）及月桂酸和肉豆蔻酸（C14,0）以3：2的比例组成的混合物（50mg）可分别抑制甲烷产量的22．2％（P〈0．01）和11．8％（P〈0．05）；添加50mg未酯化C14,0使甲烷产量降低3．4％（P〉0．05）；不同日粮类型上饲料产气量、瘤胃液pH值和氨氙浓度差异显著（P〈0．01）。     

瘤胃保护性氨基酸对内蒙古白绒山羊氮消化代谢的影响

选用9只安装永久性瘤胃瘘管，十二指肠近端瘘管和回肠末端瘘管的内蒙古白绒山羊半同胞羯羊，随机分为3组，即保护性氨基酸组（A组）、常规氨基酸组（B组）和对照组（C组），每组3只进行动物试验。采用体内法研究在相同蛋白质水平（CP 9．93％）日粮条件下，日粮中添加瘤胃保护性蛋氨酸（RPMet）和瘤胃保护性赖氨酸（RPLys）对内蒙古白绒山羊氮消化代谢的影响。结果表明：在内蒙古白绒山羊基础日粮中添加RPMet和RPLys显著地增加了绒山羊的干物质采食量DMI（P〈0．05），提高了机体氮的沉积（P〉0．05），并有降低尿中尿素氮（UUN）排出量的趋势（P〉0．05）。     

瘤胃补充保护蛋氨酸和十二指肠灌注蛋氨酸对奶牛生产性能的影响

以泌乳中后期奶牛为试验对象，研究了瘤胃补充保护蛋氨酸及十二指肠灌注蛋氨酸对生产性能、乳成分及氮代谢的影响，结果表明：瘤胃补充保护蛋氨酸及十二指肠灌注蛋氨酸能显著增加血浆尿素氮、血浆甘油三酯、奶中尿素氮浓度（P〈0．05），对产奶量、乳成分、瘤胃液氨氮、血浆葡萄糖无显著影响（P〉0．05）。     

小麦面筋蛋白对山羊瘤胃运动的影响

采用活体瘤胃运动测定装置，测定山羊日粮中添加小麦面筋蛋白条件下瘤胃运动的变化。结果表明；4只山羊试验期与对照期相比，瘤胃平滑肌收缩力平均提高31．2％，差异极显著（P〈0．05）。15min内，瘤胃平均蠕动持续时间延长34．1％，差异显著（P〈0．05）。瘤胃蠕动频率下降25．1％，差异显著（P〈0．05）。建立的瘤胃运动检测装置能够灵敏地检测山羊瘤胃运动变化规律。同时利用家兔小肠体外培养装置检测到小麦面筋蛋白通过瘤胃微生物降解作用生成的阿片肽活性，为反刍动物瘤胃代谢调控的研究提供理论依据。     

饲喂不同种类粗饲料的辽宁绒山羊瘤胃内酸碱环境及氮代谢的研究

本试验选择9只年龄3．2±0．2岁、体重50．4±2．6kg的装有永久性瘤胃瘘管的成年辽宁绒山羊公羊为试验动物。采用随机区组设计,将动物分为3组,分别饲喂给以玉米秸、大豆秸、花生秸为主的1、2、3号试验日粮,每天8：00和16：00饲喂,全天自由饮水。试验预试期15d,试验期15d,连续7d测排尿量,采集瘤胃液、尿液,研究瘤胃内酸度和氮代谢参数。结果表明：三组的瘤胃液pH、乳酸浓度、总酸度、TVFA和戊酸均差异不显著（P〉0．05）。从试验1组到3组,瘤胃液TVFA浓度、乙酸浓度、丙酸浓度、异丁酸浓度、丁酸浓度、异戊酸浓度均呈增加趋势;其中试验3组的丙酸和异丁酸、异戊酸均显著（P〈O．05）高于1组;并且试验3组的丁酸极显著（P〈0．01）高于1组;其他的差异不显著（P〉0．05）。试验1组瘤胃NH4-N极显著（P〈0．01）低于试验2组和试验3组,而后两组差异不显著（P〉0．05）;试验1组uN浓度显著（P〈0．05）低于试验3组,但与试验2组差异不显著（P〉0．05）;三个试验组瘤胃液BCP浓度和MCP合成量均差异不显著（P〉0．05）,但试验2组与3组BCP浓度和MCP合成量均高于试验1组。相关分析表明,瘤胃MCP（Y,g／d）合成量与瘤胃液TVFA（x,mmol／L）浓度存在显著相关关系：y=2．32x＋2．22,r2=0．61,P〈0．05;瘤胃MCP（y,g／d）合成量与瘤胃液丙酸浓度（X,mm01／L）存在显著相关关系：y=0．23x＋9．68,r2=0．64,P〈0．05;瘤胃液MCP（Y,g／d）与UN（x,mg／L）存在显著的线性关系：y=1．32x＋2．53,r2=0．78,P〈0．05。因此,以花生秸为主的日粮瘤胃液BCP浓度、MCP合成量较高,秸秆粗饲料转化利用效率较好,提高该日粮的能量蛋白水平会进一步增加微生物蛋白的合成和动物对其的利用。     

高精料条件下酵母培养物对混合瘤胃微生物体外发酵的影响

采用山羊瘤胃液的体外批次培养研究了酵母培养物对混合瘤胃微生物体外发酵的影响。发酵底物精粗比为7：3,酵母培养物添加量为0、0．75g／L、1．5g／L、2．25g／L。结果表明,发酵各时间点,各处理组的pH值较对照组均显著降低（P〈0．05）。与对照组相比,发酵24h、36h、48h时,各处理组氨氮浓度显著降低（P〈0．05）,2．25g／L处理组的TVFA浓度显著升高（P〈0．05）。各时间点,三个处理组的乙酸浓度与对照组相比差异均不显著,而发酵24h、48h时,三个处理组的丙酸浓度均高于对照组（P〈0．05）。发酵24h、48h时,1．50g／L处理组的乙丙比较对照组显著降低（P〈0．05）。在整个发酵期内,1．50g／L、2．25g／L处理组的累积产气量均显著高于对照组（P〈0．05）,各组干物质消失率无显著差异（P〉0．05）。结果显示,酵母培养物能够显著提高瘤胃VFA浓度,降低乙酸／丙酸比例,改变瘤胃发酵类型。     

不同饲料铜源对西门塔尔牛瘤胃营养物质降解率的影响

选用5头体重420kg±15.2kg、年龄2.5岁、装有永久性瘤胃瘘管的中国西门塔尔牛阉牛,采用5×5拉丁方设计,以风干玉米秸秆和混合精料为基础日粮,分别在基础日粮风干物质基础上添加硫酸铜、富铜酵母、赖氨酸铜、蛋氨酸铜和包被铜（8mg铜／kg日粮）,研究不同铜源对瘤胃营芥物质降解率的影响,结果表明：富铜酵母组和蛋氨酸铜组玉米秸秆干物质和有机物质的瘤胃有效降解率显著高于硫酸铜组（P〈0.05）,但与赖氨酸铜组和包被铜组差异不显著（P〉0．05）。硫酸铜组中性洗涤纤维和酸性洗涤纤维瘤胃有效降解率显著低于其他铜源组（P〈0.05）,赖氨酸铜组、蛋氨酸铜组和包被铜组干物质、有机物质及粗蛋白质有效降解率显著低于硫酸铜组（P〈0.05）,但与富铜酵母组差异不显著（P〉0.05）。综合比较,包被铜和蛋氨酸铜效果较好,其次为富铜酵母和赖氨酸铜,硫酸铜较差     

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.