内蒙古中东部扁蓿豆形态特征及物候期的观察与分析研究

通过对内蒙古中东部地区18个扁蓿豆居群6项形态学指标与物候期的分析研究，得出如下结论：（1）源自4个不同地区间的扁蓿豆，株高、叶色、生长习性方面均无显著差异，而叶型、花冠颜色、荚果形状的表现差异显著；（2）依据对形态建成的贡献率来看，可将6项形态学指标划分为3类，即第一类是株高、生长习性、荚果形状，第二类是叶型，第三类是花冠颜色、叶色，其中株高是影响形态建成的主要因子；（3）扁蓿豆4个原产地在积温、降雨量等气候条件及环境条件方面的差异较大，故不同来源的扁蓿豆居群间物候期差异明显。     

不同扁蓿豆材料抗旱性比较研究

通过测定叶夹角、叶面积、保水力、光合强度、水分利用效率和电导率等指标，对不同来源的6份扁蓿豆材料进行了抗旱生理学方面的研究。其中，保水力、光合强度、水分利用效率为扁蓿豆抗旱性研究的适宜指标；综合评价表明3号和6号扁蓿豆材料的抗旱性较强。     

太空搭载对扁蓿豆种子萌发及植株生长的影响

利用新一代载人飞船长征五号B运载火箭搭载3个不同株型的扁蓿豆品种(直立型扁蓿豆、蒙农1号扁蓿豆、蒙农2号扁蓿豆)种子67h,以探求太空环境对3个扁蓿豆种子萌发及其植株生长的影响.结果表明,太空搭载促进了蒙农1号扁蓿豆和蒙农2号扁蓿豆种子萌发,植株在生长过程中出现一些优异性状变异,诱变率为2.22％～4.26％.其中,第...     

不同覆盖模式对陇中干旱区扁蓿豆草地土壤酶活性的影响

研究不同覆盖模式对陇中干旱区扁蓿豆(Medicago ruthenica)土壤酶活性的影响，以期为该地区扁蓿豆种子生产提供理论依据。于定西市安定区进行了为期3年(2017-2019年)的田间试验，以平作处理为对照，设置垄沟覆膜、地膜平覆、垄沟覆秸、平作覆秸和垄沟5种处理，研究了扁蓿豆草地土壤酶活性的变化特征。结果表明：扁蓿豆生长第2年、第3年垄沟覆秸和平作覆秸处理的土壤脲酶活性、蔗糖酶活性、碱性磷酸酶活性、纤维素酶活性和过氧化氢酶活性均显著高于其他处理。0～10 cm土层，垄沟覆膜、地膜平覆、垄沟覆秸、平作覆秸和垄沟处理与平作处理相比，生长第2年、第3年平均土壤脲酶活性分别提高了24.4%、22.6%、33.9%、26.4%和3.4%;生长第2年、第3年平均土壤纤维素酶活性分别提高了19.2%、4.9%、108.3%、105.0%和0.9%。总体来说，各处理对扁蓿豆生长第2年和第3年草地0～10 cm土层土壤酶活性影响较大，且秸秆覆盖种植的土壤酶活性最高。     

苜蓿锈病寄主范围研究

通过室内和田间人工接种苜蓿锈病病原物,观察苜蓉病的寄主范围。研究表明,苜蓿锈病的寄主除苜蓿属的植物外,扁蓿豆属的扁蓿豆、三叶草属的白三叶草、野火球等均是该病原锈菌的夏孢子的寄主,大戟属的乳浆大戟是苜蓿锈菌的转主寄主。扁蓿豆、罢火球是国内外未见报道的新寄主,乳浆大戟是国内尚未见报道的转主寄主。     

扁蓿豆生长发育规律的研究

通过4年的种植观察发现,种植第1年扁蓿豆和苜蓿生长都较缓慢,扁蓿豆的越冬率在l～4年内随着生育年限的增加而提高,而苜蓿的越冬率比扁蓿豆稍低.返青都在4月末,从返青到成熟期的生育天数扁蓿豆为120d,苜蓿为103d.生活第2年的扁蓿豆草层最大鲜量出现在30～40cm处,其中叶量占52.4%;生活第2年和生活第3年的苜蓿草层结构最大鲜量都出现在40～50cm处,分别为50.6g和55.2g,比扁蓿豆分别少了12.4g和7.2g.种子产量第3年最高,扁蓿豆为188.4kg/hm2,苜蓿为211.95kg/hm2.扁蓿豆的生育期较长,第1年为150d,第2年为125d,第3年为120d;而生活第2年的苜蓿生育期为120d,第3、4年都为103d.     

“龙牧801号”与“龙牧803号”苜蓿新品种选育报告

“龙牧８０１号”与“龙牧８０３”苜蓉新品种，是１９７６－１９９２年期间，用黑龙江省西部羊草草甸草原上的野生扁蓿豆（ＭｅｌｉｓｓｉｔｕｓｖｕｔｈｅｎｉｃｕｓＣ．Ｖｃｈａｎｇ）与黑龙江省方良种肇东苜蓿（ＭｅｄｉｃａｇｏＳａｔｉｖａｚｈａｏｄｏｎｇ）利用辐射人工诱变方法，对亲本二倍体扁蓿豆与四倍体紫花芷进行辐射处理，动摇了亲本遗传性，提高了新合性，攻克了远缘杂交关，杂成功。采用集团选择法选育，历经了１６     

内蒙古干旱、半干旱地区野生扁蓿豆种子贮藏蛋白质的变异

扁蓿豆是异花授粉的多年生二倍体植物，分布于内蒙古中东部地区。利用SDS聚丙烯酰胺垂直板凝胶电泳技术对采自内蒙古5个地区的20个居群的种子贮藏蛋白质进行了研究。结果表明，供试材料蛋白质分子量介于140kDa-13kDa之间，共在36个点位出现了蛋白质带。分子量为41kDa、31kDa及13kDa点位的3条带在供试材料中全部出现。另外，第1和第17点位带表现频度比较低。对20个居群蛋白质带信息进行相异性平均聚类分析，共聚为六类：聚类Ⅰ包括赤峰市2个居群和锡林郭勒盟1个居群；聚类Ⅱ包括赤峰市1个居群、锡林郭勒盟2个居群和乌兰察布市2个居群；聚类Ⅲ包括通辽市1个居群、赤峰市2个居群、锡林郭勒盟2个居群和呼和浩特市1个居群；聚类Ⅳ包括呼和浩特市1个居群和乌兰察布市2个居群；聚类Ⅴ包括呼和浩特市和乌兰察布市各1个居群；聚类Ⅵ只有锡林郭勒盟1个居群。据此推测，扁蓿豆是蛋白质多样性的种群。     

青藏扁蓿豆根瘤菌接种效果试验

对青藏扁蓿豆进行了根瘤菌接种试验,结果表明:青藏扁蓿豆的结瘤率接种比对照平均提高52.9%。接种使青藏扁蓿豆的干草产量提高59.6%~69.2%。     

基于trnL-trnF序列的扁蓿豆和青藏扁蓿豆遗传多样性及其群体遗传结构分析

利用青藏高原及其毗邻地区的7个青藏扁蓿豆(Medicago archiducis-nicolai),以及来自上述地区和内蒙古的3个扁蓿豆(M.ruthenica)野生群体,根据叶绿体trnL-trnF基因间隔区序列,对其遗传多样性和群体遗传结构进行了分析。对161个个体的trnL-trnF序列的分析,共检测到11个核苷酸变异位点,定义了14种单倍型。对单倍型在不同群体中的分布分析显示,青藏扁蓿豆在青藏高原东南边缘地区可能存在避难所,同时在青藏高原边缘地区可能发生了青藏扁蓿豆向扁蓿豆群体的基因入侵。空间分子变异分析和基于K-2P遗传距离的群体聚类均支持将上述群体分为扁蓿豆和青藏扁蓿豆两组,组间的遗传分化程度很大。分子变异分析表明,群体内的遗传变异明显大于群体间的变异,但部分群体间存在较高水平的遗传分化;错配分布和中性检验表明,在采样范围内两种扁蓿豆都没有经历明显的近期种群扩张。研究认为,青藏高原复杂的地形结构、冰期时的气候波动以及扁蓿豆本身的进化历史可能是造成其现今遗传结构形成的主要原因。     

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