四种豆科牧草萌发与幼苗抗旱性试验

干旱对豆科牧草的影响广泛而深刻,它表现在生长发育的各阶段,然而种子能否在逆境中萌发、生长是豆科牧草能否定居的先决条件[1]。不同的豆科牧草对干旱的适应性有所不同,在形态指标、生态指标上都有明显的差异。试验通过对4个不同种的豆科牧草的萌发指标与部分生态指标进行比较,分析了豆     

果洛地区多年生牧草引种试验初报

在果洛地区两个试验点同时进行２５种牧草的引种试验和室内发芽试验。结果表明：１１种禾草和２种豆科牧草表现良好，６种禾草和１种豆科牧草一般，３种禾草和１种豆科牧草农现差。     

豆科牧草化感作用初探

采用培养皿滤纸的生物检测方法对红三叶、白三叶和紫花苜蓿3种常用豆科牧草的化感作用进行了初步研究。结果表明：3种豆科牧草在一定的播量下，对萝卜、青菜、番茄等受体植物生长表现出明显的抑制作用，使发芽率、苗长、根长、苗干重、根干重明显比对照降低，且抑制作用的强弱与豆科牧草种子播量有关，说明3种豆科牧草均存在较大的化感作用潜势。     

豆科牧草化感作用初探

采用培养皿滤纸的生物检测方法对红三叶、白三叶和紫花苜蓿3种常用豆科牧草的化感作用进行了初步研究。结果表明：3种豆科牧草在一定的播量下，对萝卜、青菜、番茄等受体植物生长表现出明显的抑制作用，使发芽率、苗长、根长、苗干重、根干重明显比对照降低，且抑制作用的强弱与豆科牧草种子播量有关，说明3种豆科牧草均存在较大的化感作用潜势。     

草甸草原区几种苜蓿适应性的初步研究

对引自加拿大的5个和中国的4个豆科牧草材料在内蒙古呼伦贝尔市草甸草原地区的适应性进行研究,目的是筛选适合当地种植的牧草。结果表明：草原3号苜蓿的适应性最强,夏播翌年越冬率在90％以上,可作为草甸草原地区推广种植的牧草。黄花苜蓿适应性最弱,越冬率在60％左右,其余7种苜蓿差异表现不显著。     

河西走廊东部豆科牧草资源及其评价

对河西走廊东部地区豆科牧草资源进行了调查研究。结果表明该区共有豆科牧草23属82种，其中野生豆科牧草52种，栽培豆科牧草30种。同时对其分布、营养价值和饲用特性进行了评价，提出了豆科牧草资源开发利用的建议。     

如何科学选择紫花苜蓿品种

紫花苜蓿是一种多年生草本豆科苜蓿属植物，其适应性广、抗逆性强、营养丰富、高产稳产、利用期长、经济效益高、生态性能好，是世界及我国的第一牧草，素有“牧草之王”的美誉，也是牧草种植中的首选。     

几种种子处理方法对牧草种子带菌及发芽的影响

用百菌清、高锰酸钾、甲醛及开水烫种对牧草种子进行消毒处理。结果表明,用百菌清、高锰酸钾对紫花苜蓿、无芒雀麦、披碱草、羊茅等种子杀菌效果好;甲醛溶液效果较差;开水烫种对较大的豆科牧草种子杀菌效果较好,而对小粒豆科种子及禾本科牧草种子有较大伤害。     

目前青绿饲料养畜存在的问题及解决措施

不同的畜禽种类对同一饲草的适应性不同：牛、羊等家畜喜食禾本科牧草，如高羊茅、多花黑麦草、苏丹草、杂交狼尾草、象草、桂牧1号等；其次是豆科牧草，如白三叶草、紫花苜蓿、饲料苕子、箭舌豌豆、圆叶决明等。猪是单胃动物，只能在盲肠内少量消化青绿饲料的粗纤维，对青绿饲料的利用率较差，特别是含     

黄土高原半干旱荒漠地区盐碱地优良豆科牧草适应性评价

筛选适宜黄土高原半干旱荒漠地区盐碱地生长的优良豆科牧草草种,为盐碱化草地植被恢复与重建提供适宜的豆科牧草资源,对该区草地生态功能恢复和畜牧业可持续发展具有重要的现实意义。文章在典型盐碱地上对引进和采集的13个耐寒性较强的豆科牧草品种的种子发芽特性和生长特性等进行了研究。结果表明:中兰2号紫花苜蓿、毛苕子和沙打旺3个耐盐牧草品种,对黄土高原半干旱荒漠地区盐碱地气候和土壤环境适应性较好,其中中兰2号表现最佳。     

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