内蒙古盐生植物的主要群落类型

通过对内蒙古自治区的盐生植被进行深入考查,发现内蒙古盐生植被荒漠22群系、草原24群系。其中,盐 生灌丛和半灌丛8群系,丛生禾草、根茎禾草盐生草甸7群系,杂类草盐生草甸19群系,一年生、二年生盐生草甸12群系。     

内蒙古盐生植物的主要群落类型

通过对内蒙古自治区的盐生植被进行深入考查,发现内蒙古盐生植被荒漠22群系、草原24群系.其中,盐生灌丛和半灌丛8群系,丛生禾草、根茎禾草盐生草甸7群系,杂类草盐生草甸19群系,一年生、二年生盐生草甸12群系.     

NaCl胁迫对甘肃省不同地区盐生草种子萌发特性的影响

对采集自甘肃省17个地区的盐生草(Halogeton glomeratus)种子进行萌发期的盐胁迫试验,测定种子发芽指标、幼苗生长指标、离子含量以及根系活力,研究NaCl胁迫对不同地区盐生草种子萌发特性的影响。结果表明：盐胁迫下,17个地区的盐生草种子的发芽率和发芽势均降低,其中,12和15号地区盐生草种子的萌发率最高,分别为对照的88.20%和91.92%,3号和17号地区盐生草的萌发率最低,分别为对照的74.98%和73.85%;各地区盐生草幼苗的株高对盐胁迫的响应不同,有6个地区盐生草的株高增大,其他地区的株高受到不同程度的抑制,其中17号地区盐生草株高受抑制最严重,为对照的82.35%。盐胁迫处理下,有9个地区的盐生草幼苗鲜重高于对照,其他地区的幼苗鲜重均低于对照;与对照相比,盐生草幼苗的干重明显升高,升幅最高的是白银市靖远县的盐生草品种,达到200.48%,最低的是民勤县收成乡的盐生草品种,为112.98%;分别测定两个发芽状况最好和最差的盐生草幼苗的离子含量,发现盐胁迫下盐生草幼苗的Na⁺含量增多、K⁺含量减少,K⁺     

盐生草根系基因HgAKR6C的克隆与初步功能分析

醛酮还原酶（AKR）是构成Shaker型K+通道蛋白的保守核心结构域，在植物应对非生物胁迫时起到关键作用。本研究采用西北旱区典型盐生植物盐生草作为研究材料，基于课题组前期盐生草根系盐胁迫转录组学数据分析结果，筛选并克隆得到耐盐基因HgAKR6C。HgAKR6C基因蛋白质编码区（CDS）全长951 bp，共编码氨基酸317个。系统发育进化树分析表明，HgAKR6C与拟南芥中AtAKR6C1基因亲缘关系最近。亚细胞定位表明该基因可能主要定位于细胞质和细胞核中。qRT-PCR结果表明HgAKR6C在盐处理24 h时表达量达到峰值。构建酵母异源表达载体转化缺陷型菌株发现，HgAKR6C基因可能参与Na+的外排和介导K+的吸收。综上所述，HgAKR6C具有调节盐生草耐盐性的功能，而盐生草根系耐盐基因HgAKR6C的调控机制还需进一步的研究验证。     

盐胁迫下星星草幼苗的生理反应：Ⅰ.盐胁迫对星星草幼功苗生长的影响

用模拟松嫩草地碱化土壤离子组成配制的混合盐溶液处理星星草幼苗，测定了长度和鲜重的变化。盐胁迫对星星草幼苗长度增长的抑制作用是地上部略强于地下部，而对于鲜重增长的抑制作用是地下部略强于地上部。     

盐生草Actin基因片段的克隆及表达

根据藜科植物的肌动蛋白(Actin)基因编码区保守序列设计一对简并引物,提取盐生草(Halogeton glomeratus)叶片的总RNA,运用RT-PCR技术扩增出Actin基因的核心序列并连接到pMD19-T载体,阳性克隆经PCR检测后进行测序。序列分析表明,盐生草Actin基因核心序列长度为598bp,编码198个氨基酸,并在GenBank中注册,登录号为KF699314,由盐生草Actin基因推导的氨基酸序列与其他几种耐盐植物的同源性均在94%以上,具有高度的保守性。采用荧光定量RT-PCR技术分析其Actin基因在盐生草不同器官的表达情况,结果显示其表达量恒定无差异,表明克隆的Actin基因可作为盐生草内参基因来研究其相关耐盐基因的表达。     

7个野生一年生早熟禾种质萌发期耐盐性综合评价

本研究用不同浓度的NaCl和Na₂SO₄溶液处理7个野生一年生早熟禾(Poa annua L.)种子，通过测定种子萌发特性的变化，研究其萌发时的耐盐能力，以期为一年生早熟禾耐盐新品种的选育提供依据。结果表明，随着NaCl和Na₂SO₄胁迫浓度的增大，7个种质的相对发芽率、相对发芽势、相对发芽指数和相对活力指数均逐渐降低，相对盐害率逐渐增大，且同一盐浓度胁迫对相对根长的抑制普遍强于相对芽长。一年生早熟禾(湟中)种子萌发时对盐溶液的耐性最强，且Na₂SO₄对一年生早熟禾种子萌发的抑制作用大于NaCl。隶属函数法综合评价显示，7个种质萌发期耐盐性强弱依次为：一年生早熟禾(湟中)＞一年生早熟禾(甘州)＞一年生早熟禾(永昌)＞一年生早熟禾(安宁)＞一年生早熟禾(天祝)＞一年生早熟禾(凉州)＞一年生早熟禾(秦州)。综上，一年生早熟禾(湟中)和一年生早熟禾(甘州)具有培育耐盐一年生早熟禾新品种的开发应用潜力。     

新疆5种藜科盐生植物的饲用价值

为了研究新疆5种藜科一年生盐生饲草红叶藜(Chenopodium rubrum)、野榆钱菠菜(Atriplex aucheri)、盐地碱蓬(Suaeda salsa)、盐角草(Salicornia europaea)和高碱蓬(Suaeda altissima)的最佳刈割时期和相对饲用价值大小,对其3个不同生育时期(营养期、初花期和结实期)的营养成分含量进行测定分析。结果表明,5种植物在初花期营养价值最高,地上部生物量能够满足载畜需求,因此适宜在初花期开发利用;5种盐生饲草在初花期与苜蓿(Medicago sativa)相比,红叶藜的相对饲用价值最高,之后依次为野榆钱菠菜、盐地碱蓬、高碱蓬和盐角草。野榆钱菠菜、红叶藜和高碱蓬甜菜碱含量丰富,在7%左右,盐角草、红叶藜和野榆钱菠菜草酸盐含量超标。总之,这5种植物均具有一定的饲用开发利用价值,但盐分含量偏高不宜长期单一饲喂反刍动物。     

盐胁迫下星星草幼苗的生理反应：Ⅱ.盐胁迫对星星草幼苗膜透性的影响

模拟松嫩草地碱化土壤离子组成配制的混合盐溶液处理星星草幼苗，测定了叶片电解质和Ｋ＾＋外渗率。其外渗率随盐胁迫的增强而增加，表明膜透性随盐胁迫的增强而增大。     

内蒙古12种盐生植物对几种无机离子的吸收及分配特性

以内蒙古中西部12种代表性耐盐植物沙枣等为研究对象,测定了其根茎叶的Na+,K+和Ca2+含量,结果表明:一年生盐角草表现出极高的Na+积累能力,12种盐生植物中除沙枣以外其他11种植物叶内的Na+含量>茎和根部,根部Na+/Ca2+<10/1。Na+积累影响了植物对K+的吸收,表现出了Na+和K+间的拮抗作用,Ca2+多集中于根部,反映了耐盐植物对离子的选择吸收能力。     

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.     

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.     

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.     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -     

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.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein