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11.
膨化血粉饲喂生长犬的效果试验   总被引:12,自引:0,他引:12  
选择健康的2月龄生长犬40只,随机分为3个试验组(A,B,C)和1个对照组(D),试验组分别饲喂添加5%,10%和15%膨化血粉的复合饲料,对照组饲喂添加8%鱼粉的复合饲料,进行30d饲哏试验。试验结果表明:A,B,C组与时照组相比日增重分别提高18.97%,2.17%和-13.55%;肉料比降低了19.62%,6.19%和-7.69%。  相似文献   
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植物生长物质的使用与绿色果品生产   总被引:3,自引:1,他引:3  
 针对人们对植物生长物质的种种偏见,阐述了植物激素与动物激素以及植物生长调节剂的重要区别,提出了植物激素对人体无毒性,植物生长调节剂可以运用于大多数绿色果品生产的建议。  相似文献   
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The ostrich is an important animal in many livestock industries. A significant threat to this industry is losses from diseases. Newcastle disease is a notifiable, highly contagious viral infection of ostriches. Avian influenza may be transmitted from waterfowl, shorebirds and gulls to ostriches. Borna disease virus is a viral neurotropic infection spread mainly by rodents and felines. Crimean‐Congo hemorrhagic fever is a viral disease transmitted by Hyalomma ticks to humans. Avipoxvirus afflicts ostrich chicks and is transmitted by mosquitoes or by direct contact with a pox lesion. Maintenance of a healthy and profitable enterprise requires the implementation, with assistance from the local veterinary authority, of comprehensive, practical and effective methods of health management and preventative medicine.  相似文献   
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There is a growing need to increase productivity in poultry. Growth hormones and antibiotics have the ability to improve health, weight gain and feed efficiency in meat‐producing animals. The growth‐promoting antibiotics are administered to poultry to improve the general performance of the chicken. However, the use of the xenobiotic drugs in food‐producing animals has been a concern and a sensitive issue of debate for several decades in the EU and many other regional blocks of the world. Consequently, the use of hormones in animal production has been banned in Italy, Denmark and Germany for over 4–5 decades, while Belgium and Greece had never permitted its use for livestock fattening purposes. Bioactive phytochemicals exhibit antimicrobial, antioxidant, antiparasitic, antiprotozoal, antifungal and anti‐inflammatory properties and consequently have several beneficial effects on appetite, growth and the immune status of the animal. In South Africa, different species of pumpkin are produced for food due to their high nutrient content. The flesh serves as a traditional food, while the seeds and peels are commonly discarded. Pumpkin seed extract is reported to be useful for immunomodulation, reproductive health, therapeutics over a wide range of disease conditions and stimulates metabolism of accumulated fats. Studies have also shown that pumpkin seeds are a valuable source of protein and fat. Their complexity and extent of bioactivity offers sustainable prospects for natural control of pathogenic/parasitic organisms, stimulate nutrition or enhance resistance to disease infections, and reduce abdominal fat and serum levels of harmful lipids, while increasing serum levels of beneficial lipids.  相似文献   
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Foal first diarrhoea is one of the most prominent problems in the early life of horses. Probiotics might have the potency to prevent or at least diminish neonatal diarrhoea. We hypothesised that the treatment of foals with probiotic strains of Lactobacillus rhamnosus and Enterococcus faecium starting early after birth and then daily over 2 weeks would prevent or mitigate foal heat diarrhoea. The influence of this probiotic treatment on diarrhoea incidence and growth and health performance of young foals was investigated. Thirty‐four foals were randomly allocated to two groups. From day 1 to 14 of life, the foals received either placebo (PG, n = 16) or the probiotic treatment (TG, n = 18). Clinical examination was performed, and the faeces consistency score (FCS, 1–5; with diarrhoea defined by ≤3) was recorded once per day in weeks 1 and 2 and once weekly in weeks 3–8 of life (WL). The body height was measured at birth and after two and eight WL. Diarrhoea occurred in the 1st WL in 19% and 61% of PG and TG foals respectively. In the 1st WL, diarrhoea lasted 0.3 ± 0.8 and 1.6 ± 1.4 days in PG and TG foals respectively. In the 2nd WL, diarrhoea occurred in 94% and 84% of PG and TG foals, respectively, and lasted for 3.0 ± 1.5 and 3.7 ± 1.6 days respectively. At least two periods of diarrhoea developed in 33% and 65% of PG and TG foals respectively. The TG foals grew slightly slower than the PG foals. The results indicated that the probiotic treatment of neonatal foals as performed in this study was not suitable to reduce diarrhoea within the first two WL, because contrary to the hypothesis, the TG foals suffered more frequently and for longer periods from diarrhoea than the PG foals.  相似文献   
18.
计算机多媒体技术和网络技术日新月异的发展,教育信息化的推进,为努力实现高校心理健康教育课程教学内容、教学手段和教学方法的全面创新,本文以《心理健康教育》网络课程为例,尝试剖析其在模式构建、教学设计、交互安排、教学应用等方面的特征,以期为开辟高校心理健康教育课程的新模式提供思路。  相似文献   
19.
利用人工模拟降雨试验,研究不同降雨强度下,不同农业耕作措施坡地水土流失特征。试验设计的坡地坡度分别为5°和15°,降雨强度分别为60、90、120 mm·h-1;耕作措施分别为等高耕作、人工掏挖和人工锄耕,以相同坡度的平整坡地作为对照。结果表明:(1)随着降雨强度的增大,各耕作措施坡地产流量显著增大1.51倍以上,最大增加幅度为等高耕作坡地的2.28倍。而坡地产沙量在降雨强度较小时增加不显著,当降雨强度增大到120 mm·h-1时,坡地产沙量显著增大;(2)与平整坡地相比,等高耕作在3个降雨强度下都具有明显的减流效益,减流量均大于15%,而人工锄耕和人工掏挖却不明显;(3)在5°坡地上,等高耕作和人工掏挖在3个降雨强度的减沙效益均大于25%,而人工锄耕减沙效益不明显;在坡度为15°、降雨强度为60 mm·h-1和90 mm·h-1时,人工锄耕和人工掏挖减沙效益与降雨强度关系无明显规律,在降雨强度为120 mm·h-1时,3个耕作措施都不能有效降低坡地产沙量。可见,水土保持农业耕作措施具有降低坡地产流量的作用,而对于坡地产沙的作用存在明显差异,在大坡度和大降雨强度下,不仅不能降低坡地产沙,反而加剧坡地土壤流失。  相似文献   
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为探明北方地区常见蔬菜中Cd的健康风险,以北京地区Cd污染的大棚菜地土壤为对象,利用盆栽实验测定了韭菜和小油菜对Cd的吸收、转运特征及2种修复剂(沸石+蚯蚓粪,凹凸棒+蚯蚓粪)对Cd污染土壤的修复效果,基于体外模拟法和人体健康风险评价方法对污染土壤修复前、后的2种蔬菜中Cd的有效性及人体健康风险进行评价。结果表明,污染土壤上的2种蔬菜中Cd含量均超过《食品安全国家标准食品中污染物限量》,但2种蔬菜对Cd的吸收具有显著差异,小油菜中Cd的含量为韭菜的2.04倍;体外模拟法测定结果表明,韭菜和小油菜中Cd在模拟人体胃液中的有效浓度分别为0.027、0.039 mg·kg-1,韭菜中的Cd对人体具有更高的生物有效性;基于人体健康风险评价方法对2种蔬菜中Cd进行健康风险评价,结果表明,污染土壤上种植的2种蔬菜中Cd对人体具有较高的致癌风险,其中,对0~6岁儿童的致癌风险大于成人(>18岁)的风险;添加修复剂可使韭菜和小油菜中Cd含量最大分别降低65.2%和72.3%;2种修复剂处理的韭菜与小油菜中Cd的生物有效性和致癌风险值显著下降,其中凹凸棒+蚯蚓粪处理土壤的2种蔬菜中Cd的致癌风险值接近安全水平。  相似文献   
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