几种培育措施对河西走廊盐化草地影响的研究

在连续３年的定位研究中：（１）对以芦苇＋海韭菜为主要的草地进行施肥、划破草皮和刈割等培育措施。结果表明，拖肥可提高草地质量，当施Ｎ量不超过３００ｋｇ／ｈｍ＾２时，草地产量随施Ｎ量的增加而增加；最佳的刈割时间为秋季；采用的划破草皮的方法对草地质量无显著的影响。（２）在芦苇－赖草为主的草地中，研究了３不同的灌溉频率处理对草地植被和土壤水盐含量的影响。草地土壤含盐量随灌溉次数的增加而降低；连续灌溉第３年     

退化人工草地更新效果观测

利用草地建植方法,对１７５．７ｈｍ＾２退化人工草地进行了更新改良,结果,当年平均干草产量达３５７０ｋｇ／ｈｍ＾２比未更新地带提高２０５８ｋｇ／ｈｍ＾２;播种牧草相对重量６５．９％,未更新地带１５．１％,优势度由重建前的２７．０％上升至６１．８％,恶性杂草竞争力下降,基本形成白叶＋黑麦草＋鸭茅＋画眉草＋红三叶＋狗尾草＋白茅＋蒿类的格局。     

江河源头草地生态环境现状及恢复途径

江河源头共有可利用天然草地１８８．６７万ｈｍ＾２,其中“黑土型”退化草地约为２１３．０３万ｈｍ＾２,此类草地鲜草产量４００．５ｈｍ＾２,植被平均盖度为４５．４２％。恢复草地生态环境的途径是：改变认识观念;建立人工草地;利用多年生人工草地进行幼畜放牧育肥;通过退化草地施肥、毒杂草防除等措施恢复天然植被。     

云南人工草地综合复壮技术的研究

用正交试验方法,通过除杂、施肥,补播等综合措施,对因杂草侵入,缺水缺肥,利用过度而导致建植草种过早丧失生产性能的“多年生黑麦草－白三叶”人工草地进行复壮试验,结果表明,施肥是较有效的复壮措施,牧草产量提高６５．４％;１００％除杂,施用尿素１５０ｋｇ／ｈｍ＾２,普钙１０５ｋｇ／ｈｍ,硫酸钾３０ｋｇ／ｈｍ＾２,松土撒播多年生黑麦草种子１３．５ｋｇ,白三叶草籽４．５ｋｇ为最佳技术组合,２年平均其牧草产量     

不同施氮量对高山草甸草地牧草产量及营养成分的影响

对高山草甸草地施氮５０ｋｇ／ｈｍ＾２和８０ｋｇ／ｈｍ＾２的试验结果：产草量提高１１０．２％和１７２．２７％，粗蛋白质产量提高１２６．３９％和１９６．１０％，但施氮对牧草其它营养成份无明显影响。实施本项技术措施后，能提高高山草甸冬春牧地的载畜量，具有显著的经济效益和生态效益。     

施氮与株丛切割对退化新麦草草地的改良效果

本文研究了施氮肥和株丛切割对退化新麦草人草地生产性能的影响，结果表明，施氮肥和株丛切割提高了新麦草草地生产性能和生产力。此外，施氮肥可改善牧草品质及土壤牮氮能力。株丛切割和施氮肥（１２０ｋｇ／ｈｍ＾２）相结合与单施氮肥相比，成本较低，对退化新麦草草地的改良效果良好，年均产草量２６７９．５ｋｇＤＭ／ｈｍ＾２。     

科尔沁草甸草原放牧强度对肉牛增重与草地的影响

研究了不同放牧强度下（０．８ｎｍ＾２／牛和１．２ｈｍ＾２／牛）科尔沁肉牛的日增重和单位面积产量的差异,以及其对草地状况的影响,研究结果表明,不同放牧强度下肉牛的日增重无显著差异（分别是０．４４１ｋｇ和０．４４８２ｋｇ）;高放牧强度的处理,单位面积的产量高（分别是０．５５２５ｋｇ／ｈｍ＾２－ｄ和０．３７３５ｋｇ／ｈｍ＾２．ｄ）,但对草地持续生产不利,导致草群中禾草比例下降而杂草比例上升。     

围栏草地施肥效果试验

１９９８年５月在黄南州河南县进行了天然草地施肥试验。结果表明：施尿素为２２５ｋｇ／ｈｍ２、１５０ｋｇ／ｈｍ２、７５ｋｇ／ｈｍ２时,其产量（ＤＭ）分别为：５４７０ｋｇ／ｈｍ２、５０９３．３ｋｇ／ｈｍ２、５０４６．７ｋｇ／ｈｍ２;比对照高３４．７３％、２５．４５％、２４．３０％;施羊板粪１５０００ｋｇ／ｈｍ２时,其产量为４８２３．３ｋｇ／ｈｍ２,比对照高１８．８０％。     

利用荒漠和盐碱地建立人工草地的效益分析

１９９１～１９９２年，在海西州德令哈市利用荒漠建立半人工草地８６．１ｈｍ＾２，利用盐碱弃耕地建立人工草地７４．６ｈｍ＾２，取得了明显的生态、社会和经济效益，建植第三年的沙打旺人工草地植被盖度由原来的１５％提高至７０％～８０％，耕层（０－３０ｃｍ）总盐平均含量由原来的９．３ｇ．ｋｇ＾－１，下降１．２３ｇ．ｋｇ＾－１，脱盐率达８６．２６％，在受益期内，１６０．７ｈｍ＾２人工、半人工草地可新增牧草３６０     

草地改良对高寒退化草地植被影响的研究

针对近年来高寒草地退化问题,进行了围栏封育、划破草皮和施肥三种改良试验研究。结果表明,三种改良措施都增加草群高度、盖度、密度、频率和产量,施肥改良使可食牧草产量增加４５．９％～１９１．１％;围栏封育使可食牧草产量增加６０．５％～１５８．３％;划破草皮使可食牧草产量增加３２．７％～１１３．９％。由此可知,施肥和围栏封育是草地改良的有效途径。     

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.