伊犁河谷不同生境羊草种群构件的年龄结构

对伊犁河谷昭苏县杨树群落(H1)、羊草单优势种群落(H2)生境内的羊草无性系种群年龄结构进行对比分析.结果表明:(1)H1、H2样地内羊草无性系种群分蘖株数量分别由3个龄级和4个龄级组成,且随着龄级的增大迅速减少;各生境羊草种群年龄结构同为增长型.(2)两个样地羊草无性系种群根茎长度均由4个龄级组成,其中H1样地羊草无性系种群根茎长度年龄结构为增长型,H2样地为稳定型.(3)两个样地羊草无性系种群分蘖株生物量与分蘖株数量龄级构成相同,年龄结构均为增长型;根茎生物量均由4个龄级组成都为稳定型.各生境分蘖株和根茎生物量年龄结构均以低龄级居于优势位置.     

松嫩平原不同生境羊草种群构件的年龄结构

年龄结构是无性系植物种群的重要属性之一。对松嫩平原长期割草草甸、封育草甸和封育积沙草甸三种生境中羊草种群构件的年龄结构调查表明:三种生境中羊草无性系种群分株的年龄结构由3～4个龄级组成,其中,长期割草草甸和封育草甸生境为增长型年龄结构,封育积沙草甸生境为稳定型;根茎均由4个龄级组成,其中,长期割草草甸和封育积沙草甸为增长型年龄结构,封育草甸为稳定型;三种生境下,长期割草草甸的分株生产力与根茎贮藏力均比较稳定,且1a、2a、3a的分株生产力与根茎贮藏力均低于其他两个生境,封育草甸和封育积沙草甸的分株生产力均随龄级的增加而下降,但根茎贮藏力在各个龄级间无显著差异。     

科尔沁草原区火电厂储灰池植被恢复阶段赖草种群生物量年龄结构

对不同植被恢复阶段赖草(Leymus secalimus)种群分蘖株和根茎构件生物量年龄结构进行了测定与分析。结果表明:在科尔沁草原,赖草的分蘖节和根茎均可存活4个年度;8月中旬,植被恢复12年和5年储灰池中赖草无性系种群的根茎分别由4和3个龄级组成,根茎生物量均呈稳定型年龄结构;两个恢复阶段赖草无性系种群的分蘖株均由两个龄级组成,生物量均为增长型的年龄结构,恢复时间短者增长型结构尤为明显;赖草无性系种群1龄级分蘖株的生产力均高于2龄级,各龄级根茎的物质贮藏具有较大的生态可塑性。     

松嫩平原不同土壤基质条件下羊草种群年龄结构的研究

通过对不同土壤基质条件下羊草Leymus chinensis种群年龄结构进行研究,结果表明:5月中旬在松嫩平原羊草种群营养生长期,分蘖株均由1龄、2龄、3龄3个龄级组成,呈增长型年龄结构,其中均以1龄和2龄级分蘖株占绝对优势,为89.4%～99.7%,3龄株仅占0.3%～10.6%;根茎均由2龄、3龄、4龄3个龄级组成,根茎长度及其质量均以2龄级最高,3龄次之,4龄最小;根茎物质的储量均随着龄级的升高而降低,羊草种群对低龄植株、根茎的大比例投资是羊草种群扩大其空间的一种十分有效的生态对策.     

内蒙古图牧吉自然保护区羊草种群营养繁殖特性的比较

在内蒙古图牧吉国家级自然保护区内,对草甸和草甸草原上灰绿型和黄绿型2个生态型羊草种群营养繁殖的诸数量特征进行了比较研究。结果表明,在2种植被类型中,灰绿型和黄绿型羊草分蘖株的数量和生物量均由4个龄级组成, 且均以4 a所占比重最小,呈稳定型或增长型龄级结构;根茎均以2 a所占比重最大,呈稳定型龄级结构;2个生态型羊草的单株生产力均以1 a分蘖株最高,且均随着龄级的增加依次减少;在整体水平上,草甸草原上灰绿型和黄绿型羊草的单株生产力均显著高于草甸;2个生态型羊草的根茎生产力均以1或2 a最高。在温带草本群落,增长型或稳定型的年龄结构、年轻龄级分蘖株和根茎旺盛的物质生产和贮存能力,是多年生无性系草本植物实现其持续繁荣的主要原因。     

新疆伊犁2种生境大拂子茅种群年龄结构研究

通过单位面积取样的方法,测定分析了新疆伊犁2种生境下大拂子茅(Calamagrostis macrolepis)种群分蘖株、根茎和潜在种群的年龄结构,旨在探索大拂子茅种群对不同生境条件的响应策略,揭示大拂子茅种群的繁殖潜力.结果表明:大拂子茅种群分蘖株在2种生境下均由营养分蘖株和生殖分蘖株组成;分蘖株、根茎、冬性苗和芽均有4个龄级;根茎分蘖节最多繁殖4个世代,最多可存活5个生长季;分蘖株数量和生物量为1龄＞2龄＞3龄＞4龄;芽数量为0龄＞1龄＞2龄＞3龄,以0龄芽占绝对优势;根茎生物量、冬性苗数量在2种生境样地也具有低龄级相对占优势的结构特征.2种生境下大拂子茅种群分蘖株、根茎、冬性苗和芽等构件均呈增长型年龄结构.     

通辽火电厂储灰池植被恢复过程中硬拂子茅种群构件的结构特征

植物种群年龄结构对于分析种群的动态和预测群落演替具有重要作用。通过对通辽火电厂储灰池植被恢复过程中硬拂子茅种群分蘖株数量和生物量、根茎长度和生物量的年龄结构以及分蘖株生产力和根茎贮藏力的比较,分析了不同恢复年限和家畜干扰条件下两个恢复区内(第1次取样,1区和2区恢复12和8年;第2次取样,1区和2区恢复16和12年)硬拂子茅种群构件的结构特征。结果表明:恢复年限至12和8年,两个恢复区分蘖株数量和生物量均为增长型年龄结构,根茎长度和生物量分别为增长型和稳定型;恢复至16和12年,两区分蘖株和根茎均为增长型,但龄级构成趋于复杂。两次取样中,两恢复区分蘖株物质生产力随龄级增加不断减少。同一恢复区第2次取样各龄级分蘖株生产力均显著低于第1次;除1龄根茎外,第2次取样各龄级根茎贮藏力均低于第1次。对于尚处于植被恢复演替初期的群落而言,继续围栏禁牧排除家畜啃食等干扰是确保植被恢复进程的可行而有效的方法。     

通辽火电厂储灰池植被恢复过程中硬拂子茅种群构件的结构特征

植物种群年龄结构对于分析种群的动态和预测群落演替具有重要作用。通过对通辽火电厂储灰池植被恢复过程中硬拂子茅种群分蘖株数量和生物量、根茎长度和生物量的年龄结构以及分蘖株生产力和根茎贮藏力的比较,分析了不同恢复年限和家畜干扰条件下两个恢复区内(第1次取样,1区和2区恢复12和8年;第2次取样,1区和2区恢复16和12年)硬拂子茅种群构件的结构特征。结果表明:恢复年限至12和8年,两个恢复区分蘖株数量和生物量均为增长型年龄结构,根茎长度和生物量分别为增长型和稳定型;恢复至16和12年,两区分蘖株和根茎均为增长型,但龄级构成趋于复杂。两次取样中,两恢复区分蘖株物质生产力随龄级增加不断减少。同一恢复区第2次取样各龄级分蘖株生产力均显著低于第1次;除1龄根茎外,第2次取样各龄级根茎贮藏力均低于第1次。对于尚处于植被恢复演替初期的群落而言,继续围栏禁牧排除家畜啃食等干扰是确保植被恢复进程的可行而有效的方法。     

松嫩平原异质生境光稃茅香种群构件结构的比较

单位面积挖掘取样,采用按分蘖节营养繁殖世代数划分分株龄级、按实际生活年限划分根茎龄级的方法,对松嫩平原草甸、弃耕地和林间草地的光稃茅香种群构件结构进行了统计比较。结果表明,三种生境下光稃茅香种群分株由1~2个龄级构成,均呈增长型年龄结构。根茎由三个龄级构成,也均呈增长型年龄结构。分株生产力和根茎贮藏力均呈现幼龄级最高,随着龄级增加依次下降。潜在种群中由1a和2a根茎产生的构件占78.6%以上。生境和龄级对分株数量、分株生产力和根茎贮藏力有显著的交互作用。在生境间,林间草地各龄级分株和根茎的数量特征均显著低于其他两种生境,其潜在种群的构件数量也最少。林间草地1a分株生产力与根茎贮藏力均高于其他两种生境。光稃茅香种群在异质生境下的种群结构既有差异性,也具有对其环境条件适应的相对稳定性。     

伊犁河谷不同生境假苇拂子茅种群构件组成及其年龄结构

假苇拂子茅是根茎禾草,属典型的无性系植物。通过生长季末期单位面积取样的方法,对新疆伊犁河谷地区不同生境的假苇拂子茅种群构件的组成及其年龄结构进行了研究。结果表明,4个样地的假苇拂子茅种群仅有样地H3是由生殖和营养分蘖株组成,其他3个样地均由营养分蘖株组成。4个样地的分蘖株均由3个龄级组成,均呈增长型年龄结构;4个样地的根茎均为2个龄级,其中又以2龄根茎占绝对优势。在生长季末期,4个样地的假苇拂子茅潜在种群均由冬性分蘖苗、根茎顶芽和各龄分蘖节向上生长的芽组成,分蘖节芽占优势地位,各龄级芽又以1龄级的占显著优势,均属于增长型年龄结构。牲畜啃食和淹水扰动对分蘖株物质生产和根茎的物质储存均有不利影响。     

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.     

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.     

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.     

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.     

Micronutrient Content of Certain Tropical Conventional and Unconventional Feed Resources of Southern India

The ash, silica and certain important micronutrients were estimated in conventional and unconventional feed and fodder resources available in Southern India. Commonly used dry roughages, such as paddy straw, ragi straw, maize kadbi/stalk, jowar kadbi/stalk, bajra stalk and wheat straw, were high in ash (9.9% +/- 0.77%) and silica (6.4% +/- 0.65%) and low in most of the other micronutrients, except iron, with paddy straw containing most silica (>9%). Cultivated non-leguminous (maize, jowar) and improved green crops (hybrid napier, guinea, green panic, NB-21, CO-1) were also high in ash (10.5% +/- 0.60% and 12.5% +/- 0.51%) but were moderate sources of P, Mg and Cu and good sources of Zn (98 +/- 13.8 ppm and 55 +/- 6.7 ppm). Leguminous green fodders (stylosanthus, lucerne, cow pea, soyabean) were excellent sources of Ca (1.9% +/- 0.16%), Mg (0.40% +/- 0.05%), Cu (30 +/- 5.2 ppm), Zn (121 +/- 14.7 ppm) and Fe (1234 +/- 166 ppm) and moderate sources of P. Mixed local grasses and weeds were high in silica (6.9% +/- 1.00%) but were good sources of Cu, Zn and Fe. Cereal grains (maize, wheat, rice, ragi) were low in ash (2.9% +/- 0.33%) and were relatively poor sources of Ca (0.22% +/- 0.03%), Mg (0.19% +/- 0.03%) and Cu (13 +/- 3.1 ppm). Pulses were low to medium sources of most minerals and good sources of Fe (1230 +/- 293 ppm). Oil seed cake/extractions (groundnut cake, cotton seed cake, soyabean meal, sunflower cake, safflower cake) and cereal by-products (rice polish, rice bran, wheat bran) were excellent sources of P (1.1% +/- 0.47% and 2.3% +/- 0.19%) and good sources of Zn (65 +/- 3.9 ppm and 66 +/- 10.7 ppm) and Fe (938 +/- 130 ppm and 662 +/- 126 ppm). Among the unconventional feeds screened, orange peel, sunflower heads, meat meal, rubber seed cake, spirulina algae and sea weeds contained plentiful Ca, Zn and Fe: tree leaves/top feeds (mulberry, erythrina, glyricidia, banana, subabul, groundnut haulms) were excellent sources of Ca (1.5% +/- 0.13%), Zn (120 +/- 22.9 ppm) and Fe (1033 +/- 133 ppm) but relatively poor sources of P. Soyabean husk, cocoa seed husk, rubber seed cake and meat meal were moderate to good sources of P (1.0% and 0.33%). The high Zn and Fe values of most feeds/fodders were probably due to soil contamination. This account of the micronutrient content of feed/fodder resources should help in strategic supplementation intended to alleviate local deficiencies.     

Bovine Mastitis in Selected Areas of Southern Ethiopia

A study on bovine mastitis, designed to determine the causal agents, prevalence of infection and impact of risk factors in three cattle breeds, was conducted in selected areas of southern Ethiopia. A total of 307 lactating and non-lactating cows, of which 162 were indigenous Zebu, 85 Jersey and 60 Holstein-Friesian, were examined by clinical examination and the California mastitis (CMT) test. Of these, 40.4% were positive by CMT and bacteriology for clinical or subclinical mastitis, with prevalence rates of 37.1% and 62.9%, respectively. Out of 1133 quarters examined, 212 (18.7%) were found to be infected, 83 (39.2%) clinically and 129 (60.8%) subclinically. The prevalence of mastitis was significantly higher in Holstein-Friesian than in indigenous Zebu, in non-lactating cows than in lactating cows, in the early lactation stage than in the mid-lactation stage, in cows with lesions and/or tick infestation on skin of udder and/or teats than in cows without this factor, and in the wet season than in the dry season. Mastitis increased with parity number (R = 0.9). Of 248 CMT and clinically positive udder quarter samples analysed microbiologically, 212 were culturally positive for known mastitis pathogens and 36 were negative. Of the 199 positive samples, Staphylococcus accounted for 39.2%, Streptococcus for 23.6%, coliforms for 14.1%, Micrococcus and Bacillus species for 8.0% each and Actinomyces or Arcanobacterium (Corynebacterium) for 7.0%. It was concluded that there was a high prevalence of clinical and subclinical mastitis, mainly caused by Staphylococcus aureus, Streptococcus agalactiae and Escherichia coli, in this study area.     

不同日粮氮水平对山羊氮代谢和微生物蛋白质合成的影响

本试验旨在探讨不同日粮氮水平对内蒙古白绒山羊氮代谢和微生物蛋白质合成(MCP)的影响,以达到提高氮利用率,减少环境污染和饲料资源的浪费。试验选用9只体况良好、体重为(43.83±2.95)kg,装有瘤胃瘘管的内蒙古白绒山羊,按体重随机分为3组,每组3只。日粮分为低氮7.5%、中氮10.5%、高氮13.5%3个氮水平。试验使用常规试验方法分析测定粪尿血液等生化指标,通过全收尿法和尿嘌呤衍生物法估测MCP。结果表明:随着氮水平增加,氨氮(NH3-N)浓度、氮摄入量、尿氮排出、尿中尿素氮(UUN)和MCP显著增加(P0.05),干物质采食量(DMI)显著降低(P0.01);沉积氮占总摄入氮的比例在中氮组最高,MCP在高氮组最高。综上所述,适当降低日粮氮水平可减少粪尿氮排放,提高反刍动物氮利用率。     

Microsporidial keratopathy in two dogs

A microsporidial keratopathy is described in two dogs. Both dogs presented with a unilateral stromal keratopathy characterized by multifocal coalescing opacities, and the diagnosis was made on histopathologic examination of keratectomy specimens. Transmission electron microscopy (TEM) on formalin‐fixed, paraffin‐embedded corneal tissue was performed in one dog, and the morphologic features were consistent with Nosema species infection. Both dogs were initially diagnosed and treated by superficial keratectomy. One dog received additional antifungal medication and underwent a penetrating keratoplasty following local recurrence two years later. No other systemic lesions attributable to the microsporidial infection were identified clinically. The clinical and diagnostic pathology findings, treatment, and follow‐up are discussed.