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51.
花生在生产过程中产生大量副产物,其营养价值较高,是重要的饲料加工原料。文章主要针对花生生产过程中副产物营养价值及在畜牧生产中的利用进行综述。 相似文献
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利用中草药防治动物疾病已经成为养殖业研究的重要课题,但对动物服用中草药的难度较大,该文改进了传统的人工胃管灌服方法的缺陷,采用将中草药与精料共煮后饲喂,方法简便、价格低廉、节省人力,对规模化养殖场群体动物的中草药应用具有良好的推广价值。 相似文献
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R. R. Woods K. C. Cameron G. R. Edwards H. J. Di T. J. Clough 《Soil Use and Management》2016,32(4):565-572
Nitrogen (N) leaching from soil into water is a significant concern for intensively grazed forage‐based systems because it can cause a decline in water quality and is a risk to human health. Urine patches from grazing animals are the main source of this N. The objective of this study was to quantify the effect that forage type and gibberellic acid (GA) application had on N leaching and herbage N uptake from urine patches on perennial ryegrass–white clover (RGWC), Italian ryegrass and lucerne. A lysimeter study was conducted over 17 months to measure herbage growth, N uptake and N loss to water beneath each of the three forage types with the following treatments: control, urine (700 kg N/ha) and urine with GA (8 g GA active ingredient/ha). Compared with RGWC (205 kg N/ha), N leaching losses were 35.3% lower from Italian ryegrass (133 kg N/ha) and 98.5% higher from lucerne (407 kg N/ha). These differences in leaching loss are likely to be due to winter plant growth and N uptake. During the winter months, Italian ryegrass had higher N uptake, whereas lucerne had lower N uptake, compared with RGWC. The application of GA had no effect on N leaching losses, DM yield or N uptake of forage treated with 700 kg N/ha urine. 相似文献
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针对蛋鸡生产过程中,鸡群体重传统监测方式费时费力、不能实时获取体重数据、监测过程易出现鸡群应激等问题,设计并搭建了蛋鸡体重实时监测系统。蛋鸡体重实时监测系统以新型栖架离地立体养殖系统中的栖杆为载体,在其两端安装质量传感器,采用LabVIEW编写蛋鸡体重实时监测程序对质量传感器的数据进行采集与处理。对蛋鸡体重实时监测系统进行测试,结果表明:1)系统对栖杆上鸡只数量识别的总体准确率达98%;2)在光期系统所监测的鸡群平均体重的变化幅度较大,与当日人工称量得到的鸡群平均体重的最大差值为292g。在暗期开始后1h系统监测的鸡群平均体重趋于稳定,且稳定值接近当日人工监测的鸡群平均体重;3)选取每日22:00—23:00系统所监测的鸡群平均体重的平均值作为当日鸡群平均体重,系统监测鸡群平均体重结果与当日人工监测结果的平均误差为±109g,最大误差±152g,相对误差2.6%~8.1%。 相似文献
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Phosphorus availability and farm structural factors: examining scarcity and oversupply in north‐east Germany 下载免费PDF全文
Assessing factors influencing phosphorus (P) availability in soils is important in preventing its overexploitation and excessive application in agricultural systems. Despite high historical P applications in the federal state of Brandenburg (Germany), county data on soil test P (STP) reveal considerable disparities in soil available P. In addition, negative soil balances as a result of small mineral P and manure inputs have been observed, raising questions about the factors leading to this situation. Our work focused on identifying possible causes operating at the farm management level by conducting a letter survey in two administrative districts of Brandenburg, the counties Barnim and Uckermark, linking farm management factors (ownership type, farm size, land tenure, animal husbandry with or without grassland and its intensity, presence of a biogas plant and organic production) to farmers’ self‐indicated levels of STP. Small‐ to medium‐sized individual farms tended to have (very) high STP, while large partnership farms and companies/cooperatives were sensitive to factors resulting in low STP. Farms with low shares of land ownership, the presence of grassland, extensive cattle farming and stockless organic farming had lower STP. On the other hand, biogas plants, partly in combination with intensive livestock (cattle) farming, were associated with larger STP. It was concluded that more care should be devoted to the design of agricultural policies and that further (inter‐ and transdisciplinary) research on this topic is needed. 相似文献
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研究心房钠尿肽基因敲除小鼠(ANP-/-小鼠)的生物学及病理学特性。ANP-/-小鼠与C57BL/6小鼠饲养于SPF级环境中,观察小鼠的繁育状况及其生物学特性,选取合适时间处死小鼠,通过HE染色观察脏器形态及组织结构。ANP-/-小鼠的繁殖周期比C57BL/6长,产仔率较低;ANP-/-小鼠肝脏、肺脏、脾脏较C57BL/6小鼠的有明显炎症反应,但是C57BL/6小鼠未见明显的病理改变。提示ANP基因的缺失可能与炎症发生有关。说明ANP-/-小鼠繁殖较慢、产仔率低,且正常繁殖的普通小鼠不会引起器官的病理学改变。但作为一种在心血管、代谢疾病上的动物模型,并与炎症甚至肿瘤有可能的未知联系的转基因动物,其很有研究和探索价值。 相似文献
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Immunoglobulin of yolk (IgY) refers to the specific antibodies from the immune eggs, is the most important immunoglobulin in the yolk,which has the characteristics of stable chemical properties, high yield, low cost, high specificity and no toxic side effects, there was no cross serological reaction among animals breeds because of a long distance. IgY has a significant advantage in animal and human disease prevention and treatment. In this research,we reviewed the application of structural characteristics, physicochemical property and action mechanism of IgY in prevention treatment of animal disease and developing prospect, especially in the treatment of animal diseases, such as diarrhea and acute treatment of animal spirit, harm, large virus disease; zoonosis seriously endanger the safety of human property; Other aspects such as aquaculture, animal fur and other major diseases. IgY could effectively prevent and treat animal diseases, but also reduce the possibility of zoonosis, which will be of great significance for the protection of personal safety. 相似文献
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