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1.
Jiafang Li Xiang Li Honggui Liu Jianhong Li Qian Han Chao Wang Xiangyin Zeng Yutao Li Wenbo Ji Runxiang Zhang Jun Bao 《Journal of animal science》2021,99(5)
An enriched environment is widely used to improve domestic animals’ welfare and promote their natural behaviors. Music can reduce abnormal behavior in humans, nonhuman primates, and rodents. However, little is known about the effects of music on pigs. This study aims to explore the effects of repeated music stimulation on the behavior, physiology, and immunity of growing pigs. A total of 72 hybrid piglets (Large White × Duroc × Minpig) were randomly divided into three groups, including music (Mozart K.448, 60 to 70 dB), noise (recorded mechanical noise, 80 to 85 dB), and control (natural background sound, <40 dB), and 6 h sound stimulation was given per day (1000 to 1600 hours) from 40 to 100 d of age. The behavioral activities of the pigs were observed during the music stimulation, and their serum cortisol, salivary cortisol, and serum immune indices were also measured. Compared with the control group, the music group and noise group increased activity but decreased lying of pigs (P < 0.05). A significant increase in tail-wagging, playing, and exploring behaviors of pigs was found in the music group (P < 0.05), and the noise significantly increased the aggressive behavior of the pigs (P < 0.05). Tail-wagging, playing, exploring, manipulating, and aggressive behaviors decreased over time. Short-term (8 d) music stimulus had a lower cortisol level than that of the noise and control groups (P < 0.05), whereas long-term (60 d) music stimulus increased immunoglobulin G (IgG), interleukin-2 (IL-2), and interferon-gamma (IFN-γ) levels (P < 0.05) and decreased interleukin-4 (IL-4) level (P < 0.05). Long-term noise stimulus significantly reduced the level of IgG (P < 0.05) but did not affect the level of IL-2, IL-4, and IFN-γ levels (P > 0.05). In conclusion, short-term music stimulus (8 d) reduced the stress response, whereas long-term music stimulus (60 d) enhanced the immune responses. In addition, the noise increased the aggressive behavior, and long-term noise reduced the immunity of the growing pigs. 相似文献
2.
Maria Antonia Machado Barbosa Kacilda Naomi Kuki Pedro Santos Peno Bengala Emilly dos Santos Pereira Angélica Fátima de Barros Sebastián Giraldo Montoya Leonardo Duarte Pimentel 《Journal of Agronomy and Crop Science》2020,206(2):263-276
Environmental conditions influence phenology and physiological processes of plants. It is common for maize and sorghum to be sown at two different periods: the first cropping (spring/summer) and the second cropping (autumn/winter). The phenological cycle of these crops varies greatly according to the planting season, and it is necessary to characterize the growth and development to facilitate the selection of the species best adapted to the environment. The aim of this study was to characterize phenological phases and physiological parameters in sorghum and maize plants as a function of environmental conditions from the first cropping and second cropping periods. Two parallel experiments were conducted with both crops. The phenological characterization was based on growth analyses (plant height, leaf area and photoassimilate partitioning) and gas exchange evaluations (net assimilation rate, stomatal conductance, transpiration and water-use efficiency). It was found that the vegetative stage (VS) for sorghum and maize plants was 7 and 21 days, respectively, longer when cultivated during the second cropping. In the first cropping, the plants were taller than in the second cropping, regardless of the crop. The stomatal conductance of sorghum plants fluctuated in the second cropping during the development period, while maize plants showed decreasing linear behaviour. Water-use efficiency in sorghum plants was higher during the second cropping compared with the first cropping. In maize plants, in the second cropping, the water-use efficiency showed a slight variation in relation to the first cropping. It was concluded that the environmental conditions as degree-days, temperature, photoperiod and pluvial precipitation influence the phenology and physiology of both crops during the first and the second cropping periods, specifically cycle duration, plant height, leaf area, net assimilation rate, stomatal conductance and water-use efficiency, indicating that both crops respond differentially to environmental changes during the growing season. 相似文献
3.
齐卡商品肉兔在不同饲养条件下的育肥效果 总被引:1,自引:0,他引:1
作者在不同条件下,采用全窝育肥法,重复两年、两个季节测定了齐卡商品肉兔的育肥效果;探讨了温度、季节、营养水平、育肥始重对育肥效果的影响。结果表明:在试验场育肥250只齐卡商品兔,90日龄育肥重2.33~2.53公斤,日均增重31克以上,耗料指数3.31:1,育肥成活率95%以上,屠宰率52%,净肉率80%,肉骨比5.35:1,兔肉品质正常。在农村条件下育肥180只,90~100日龄育肥重2.2~2.4公斤,耗精料指数2.55:1,育肥成活率88%~93%。饲养齐卡商品兔与饲养二元杂交兔相比,每只可增加经济收入20%以上。育肥季节和始重明显影响育肥未重(P<0.05)。依据本试验,作者建议齐卡商品兔适宜35日龄断奶,育肥始重应不低于600克;寒冷季节育肥,育肥第一月的室温应不低于10℃。育肥适宜营养水平建议消化能(DE)2600~2700大卡/公斤,粗蛋白(CP)18%,粗纤维(CF)12%以上。 相似文献
4.
选用6只9周龄新西兰母兔,评定环境温度和饲粮营养浓度对生长期母兔代谢能利用率的影响。试验在密闭式的小动物呼吸测热柜中进行。分别对处于环境温度为20±2℃和30±2℃,采食两种不同营养浓度的试兔进行测试。饲粮营养水平实测值,分别为12.22kJ ME/g和13.49kJ ME/g;粗蛋白质(CP)分别为17.3%和21.6%;中性洗涤纤维(NDF)分别为23.7%和16.5%。结果表明:环境温度影响试兔的能量平衡,它与采食量间存在着显著的相关。20±2℃时,相关系数r=0.798;30±2℃时,相关系数r=0.875。在本试验设计范围内,饲粮营养浓度并不影响代谢能食入量(ME_I),热增耗(HP)和能量平衡(EB)。当环境温度为20±2℃和30±2℃时,表观代谢能转化率(NE/ME)分别为51%和71%;每天每兔每千克代谢体重代谢能维持需要分别为396 kJ和361 kJ。试验结果认为:环境温度影响营养物质消化率(P相似文献
5.
WANG Xiaoxiao MA Qiangqiang CAO Xiaojun . Wuhu Luhuan Company Ltd. of Landscape Architecture Wuhu P.R.China . Northwest Minorities University Lanzhou P.R.China . The Scientific Technological Incorporated Company of Donghua Engineering Hefei P.R.China 《中国林业科技(英文版)》2005,4(2):36-43
1 GENERALRoof gardens can be extensively interpreted as ageneral designation, which means building variousrecreational garden on roofs, gazebos and terracesof both ancient and modern buildings, structures, andbridges (flyovers) (Jin Weiping, 1996). Cities aredensely populated and land is costly, so shortage ofland is one of the restrictive factors in green urbandevelopment. According to statistics, the green spaceis 2~3 m2 per capita in Chinese cities. As a result, todevelop roof gardens h… 相似文献
6.
ZIKA种母兔饲粮适宜营养水平的研究 总被引:2,自引:0,他引:2
连续三年在相同的繁殖季节,使用齐卡N系母兔148只,分别观察测定了四种不同营养水平组合日粮对不同繁殖状态母兔繁殖能力的影响。结果表明:在延期繁殖(母兔断奶后再配种)条件下,不同能量、蛋白水平对母兔繁殖性能的影响差异不显著(P>0。05),但中能高蛋白(DE10.88兆焦/公斤、CP19%)的第3组日粮略胜于其它组合。由此得出,在引延期繁殖的ZIKA能繁母兔,适宜的营养水平为:消化能(DE)10兆焦/公斤,粗蛋白(CP)19%,粗纤维(CF)10%。在母兔进行半频密繁殖(母兔产后第14天开始配种)情况下,高能高蛋白(CDE12.13兆焦/公斤、CP19%)饲粮对提高繁殖性能的效果明显优于高能低蛋(DE12.13兆焦/公斤,CP15%)和低能低蛋白(DE10.88兆焦/公斤)和CP15%)饲粮(P<0.05),尤其对提高母兔泌乳力效果明显(P<0;01),因此,实行频密(产后立即配种)或半频密繁殖的母兔,适宜营养水平为消化能12兆焦繁殖的母兔,适宜营养水平为消化能12兆焦/公斤,粗蛋白19%,粗纤维9-12%. 相似文献
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10.
本试验选用3头6月龄左右断奶中国荷斯坦公牛,在试验全程喂以相对稳定的日粮,从2003年11月1日开始,到2004年6月20日结束,用以测定中国荷斯坦生长公牛在不同生长期对饲粮中各营养成分的代谢情况。试验结果表明:日粮中的DM、OM、NDF、ADF、淀粉和粗蛋白质的表观消化率随着生长犊牛的月龄的增加而增加(P<0.05);并且9月龄以后,DM、OM、NDF、ADF和粗蛋白质的表观消化率增长不明显(P>0.05),淀粉的表观消化率则在11月龄以后增长不明显(P>0.05)。氮的净吸收率随着生长犊牛的月龄的增加而下降(P<0.05),且在9月龄以后下降不明显(P>0.05)。 相似文献