牧草种植中应注意的几个问题

由于牧草种植兼顾产业结构调整和生态环境建设双重效用，越来越受到全社会的关注，呈现出强劲的发展势头。虽然我国牧草种植已有多年历史，但大面积推广还处于起步阶段，在种植过程中应注意以下几个方面的问题：一、品种问题牧草品种繁多，每一种牧草品种的正常生长发育都要有其相适应的生态条件。在品种选择上首先要选择适宜当地气候条件和土壤条件的牧草品种，再从这些品种中选取产草量高，适口性好，饲用价值大的品种。其次在品种选择上要注意禾本科牧草与豆科牧草同时选种。因为豆科牧草含有较高的蛋白质和钙等营养元素，而禾本科牧草含…     

广西岩溶区优质牧草的筛选研究

2003-2006年通过对12个牧草品种的株高、产量、营养成分等指标的试验比较,结果表明：在本试验混播牧草中生产性能较好的禾本科牧草有巴拉草、非洲狗尾草、宽叶雀稗、狗牙根和坚尼草,豆科牧草有合萌、184柱花草,适宜在广西红壤区推广种植。     

农区种植牧草应解决的问题

种草养畜,已成为我国广大农区种植业结构调整和农民致富增收的亮点,但由于牧草种植在我国农区起步较晚,广大农民对牧草种植知识知之甚少,牧草种植存在许多误区。因此,农区种植牧草时应讲究科学,注意解决好以下四个方面的问题: 1 科学选择品种 优质牧草品种很多,不同的品种,对气候、土壤有     

农区高产牧草饲料作物种植模式

为了合理利用土地资源、培肥地力，充分发挥各种牧草饲料作物的潜力，达到高产、稳产的目的，应根据当地的气候、土壤条件、饲养畜禽的种类及其利用牧草饲料的目的，选择适宜的牧草饲料品种。例如，红壤旱地宜选择耐瘠、耐旱的牧草饲料作物；肥力水平高、有灌溉条件的旱地，可选择高产潜力大的牧草饲料作物；农田除选择高产的牧草饲料作物外，还应考虑是否耐渍；     

优良豆科牧草选育试验研究

我省草业科技工作者在牧草选育方面取得了很大的成绩，筛选出了适应江西红壤丘陵种植的高产优质的多年生牧草30个，但豆科牧草的引种筛选工作仍不尽人意。部分豆科牧草有的因结实率低、收种困难，较难适应夏季高温干旱的气候条件，推广面积不大；有的又因不能开花结实难以越冬而被淘汰。筛选培育能在江西越冬、越夏、生物产量和种子产量高且易收种，又能为畜禽和水土保持利用的豆科牧草品种已成为我省草业科技工作者亟待解决的课题。本试验研究是在“八五”工作的基础上根据牧草生态、生物学原理，对适应本地区栽培的豆科牧草品种和野生豆科…     

鹅全程饲养管理操作规程与疫病防治

1．1牧草品种选择鹅喜食的牧草有黑麦草、齿缘苦荚菜、毛苕子、豌豆、甘蓝、籽粒苋、白三叶以及一些菜叶、藤叶和野生牧草等，其中黑麦草、齿缘苦荚菜是养鹅最好的牧草品种。但为了保证鹅的青饲料均衡、充足供应，必须搭配多种牧草，饲养种鹅更要注意牧草全年均衡供应。种植牧草应选择水肥条件好的地块或充分利用秋冬闲田，根据牧草的不同播期，安排牧草的种植，如秋冬闲田种植黑麦草、毛苕子、豌豆等冬性牧草，春季利用空闲田种植苦荚菜、籽粒苋等春性牧草。     

燕麦牧草倒伏情况调查

燕麦为多用途粮经作物,在北方种植很普遍,永寿县鸿运达种养专业合作社联合社于2018年首次引进燕麦品种24个,进行种植试验、示范,从中选择适宜渭北旱塬种植的燕麦牧草品种,为解决冬季牛羊牧草短缺进行探索与研究,2020年种植燕麦牧草品种3个100 050 hm~2,因持续连阴雨全部倒伏而绝收。本文分析了2020年种植的3个燕麦牧草品种,因持续连阴雨全部倒伏而绝收的原因,并对今后永寿燕麦饲草发展提出了建议。     

发掘野生牧草种质资源提高退耕种草质量效益

内蒙古自治区作为国家退牧还草等生态建设项目重点地区，随着退饼人工种草的进一步开展，种植牧草品种单一，特别是多年生牧草品种单一的问题也逐渐显现出来。改变这种状况，必须从实际出发，立足当地自然资源优势，坚持引进优良牧草品种与开发当地野生牧草品种资源相结合，发掘野生牧草品种资源，大力推广种植野生优良牧草，调整牧草品种结构，形成种类丰富，形式多样的人工草地牧草种植格局，才能不断提高退耕种草的质量效果。     

紫花苜蓿引种及其对奶牛饲喂效果的试验

紫花苜蓿(medicago satica)属多年生豆科牧草，产草量高，草质优良，干物质中粗蛋白含量达15％～25％，相当于豆饼的1／2，比玉米高1．0～1．5倍，是优质的蛋白质饲料，素有“牧草之王”之美称。金衢盆地系红壤地区，因气候及土地状况等原因，自然饲草资源缺乏，适宜栽种的饲料作物和牧草品种较少，草地植被以禾本科为主，牧草产量和品质欠佳，紫花苜蓿的种植一直以来是空白。为了改良金华市牧草品种结构，提高牧草产量和质量，以适应当地奶牛业的迅速发展，进行了紫花苜蓿引种栽培及对奶牛饲养效果的试验。     

引进人工牧草品种在红壤低丘岗地的生长观察

“九五”期间，弋阳县承担了飞播牧草示范基地项目建设。配合该项目建设，1998年引进了温季和热季人工牧草5个品种进行种植试验。通过8年种植观察，从中筛选适合本县自然环境、产草量高、草质好的牧草品种，作为今后在本县推广的当家品种。     

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.     

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.     

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.     

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