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51.
Gas and short‐chain fatty acid production from feeds commonly fed to red deer (Cervus elaphus L.) and incubated with rumen inoculum from red deer and sheep
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Andrej Lavrenčič Darko Veternik 《Journal of animal physiology and animal nutrition》2018,102(5):1146-1153
Efficient red deer supplementary feeding depends on estimations of the nutritive value of offered feeds, frequently estimated with the use of equations derived from domestic ruminants. The aim of this study was to compare the 24‐hour in vitro true dry matter degradability (ivTD24), in vitro gas production (GP) kinetic parameters, GP in 24 hr of incubation (GAS24) and short‐chain fatty acid (SCFA) and microbial biomass (MBS) produced after 24‐hour incubation of feeds in inoculum prepared from sheep and red deer rumen fluid. Eleven feeds, frequently consumed by red deer in Slovenia, which occur either naturally (two fresh grasses, chestnut fruits and common and sessile oak acorns) or are fed as winter supplemental feeds (two grass hays, two grass silages, apple pomace, fresh sugar beetroot), were investigated. The in vitro GP kinetic parameters, GAS24 and ivTD24, did not differ between animal species. Amounts of SCFAs were greater (p < 0.05) when feeds were incubated in sheep inoculum, while molar proportions of acetic and propionic acids did not differ. Molar proportions of butyric acid produced during incubation of high fibre feeds did not differ between animal species, but were higher (p < 0.05) when feeds high in starch or sugar were incubated in red deer inoculum. Greater production of SCFA by sheep rumen microbes suggests better coverage of host animal with energy precursors, while greater production of MBS by red deer rumen microbes suggests better coverage of host animal with protein. Results also suggest that rumens of sheep and red deer are inhabited by different microbial communities, which did not affect the extent of in vitro GP and degradation of feeds used in the present experiment. However, the possibility exists that the divergent nutrient use could be a consequence of different priming by different feeds of the donor animal diets. 相似文献
52.
硼氢化钠的水解产物是一种新的储氢材料,其良好的可逆储氢能力在5MPa氢气压力真空条件下3分钟后在室温下吸收氢150。根据报道,它已被证明,这两种改变的催化剂NaBH4水解和添加催化剂直接插入接口是两个非常有效进一步提高接口的储氢容量。对hpsb-y2o3脱氢TiO2分别掺杂均达到重量2.4%和重量4.6%。重要的是对hpsb-y2o3可逆的脱氢能力不下降后成功———超循环。相比之下,对hpsb-ceo2可逆脱氢高达到重量5.9%,在室温下5分钟后3MPa氢气压力150氢吸附。 相似文献
53.
MAO Ran LI Qing-quan SHI Yan LAN Xiang-li WANG Min ZONG Ze-jun XIA Guo-zhong HAN Tian-long 《中国畜牧兽医》2015,42(12):3308-3314
In order to explore the effect of different L-lysine levels added in semen dilution on the fresh Dorper sheep quality stored at liquid state,3 health Dorper ram were used to collect semen which were equal-packaged and added to solution containing different levels (0,0.1,0.2,0.3,0.4 and 0.5 g) L-lysine in 120 mL diluent and at 0,6,24,30,48,54,72 and 78 h,the sperm motility,membrane integrity and acrosome integrity were detected.The results showed that the sperm motility in groups added 0,0.1 and 0.2 g L-lysine were higher than other groups,and that in 0.4 and 0.5 g L-lysine groups decreased faster than other groups;The sperm motility in 0.5 g L-lysine group reduced to 0 at 30 h,and it reduced to 0 at 48 h in the group added 0.4 g L-lysine;The effective survival time and survival index in the group added 0.1 g L-lysine was higher than other groups (P< 0.05);The membrane integrity of 0.1 g group was the highest,that had no significant difference with control group from 0 to 54 h (P >0.05),while after 72 h the two groups had significant differences (P< 0.05).The membrane integrity in 0.4 and 0.5 g groups were the worst,and that was significant different with other groups (P< 0.05);The acrosome integrity of 0.1 g group was the highest which had no significant difference with control group (P >0.05),0.4 and 0.5 g groups were the worst,the difference between them was not significant (P >0.05),while was extremely significant difference with other groups except for 0 and 6 h (P< 0.01).The results suggested that dilution added a high concentration of L-lysine could inhibit sperm quality,when the count of L-lysine was more than 0.2 g,sperm quality was significantly decreased,adding 0.1 g L-lysine could improve Dorper sheep fresh sperm quality stored at liquid state. 相似文献
54.
根据GB/T 8086—2008规定的测定方法,分析了测定过程中的随机效应与系统效应,计算这两种效应对测定过程导致的不确定度和,最终对本方法所产生的不确定度给予综合评定。 相似文献
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56.
文章介绍了以STC12C5201AD为核心的可燃气体检测与报警装置设计.该装置用催化型可燃气体传感器将气体浓度转换为对应的电压值,然后采用A/D进行采集和标度变换,最后由单片机进行信息处理,判断浓度是否超标,并控制报警动作. 相似文献
57.
58.
种子的萌发除了与自身的生理结构、萌发时外界条件有关外,不同的贮藏条件和时间处理对种子萌发也有影响.本实验以无瓣海桑种子为研究对象,通过无瓣海桑种子的基本特征及不同贮藏环境(常温、常温干燥、-4℃、-70℃分别对应Ⅰ、Ⅱ、Ⅲ、Ⅳ)和时间(15,30,45,60,90 d)下其种子萌发特性的分析发现:径级对无瓣海桑的果重和种子的粒数均有显著影响;低温处理可显著缩短种子的萌发时间,同时有助于保持无瓣海桑的种子活性;无瓣海桑种子的活力会随着贮藏时间的增加而下降,因此不适宜长期贮藏,但短期贮藏时低温干燥贮藏可较好地保持其种子活力. 相似文献
59.
在现代新的形势下,粮食仓储的管理工作显然是非常重要的,对于保障粮食安全是非常重要的,因为不管是从哪方面考虑,它都占据着一个至关重要的位置。所以,做好粮食工作的关键之一就是要加强对粮食仓储的管理。 相似文献
60.
为研究炭化竹原纤维的特性,进一步提升竹原纤维的使用性能,拓宽竹原纤维的应用领域,采用可控电炉制备了不同炭化温度和不同保温时间条件下的炭化竹原纤维,利用全自动比表面积及孔隙度分析仪测试了炭化竹原纤维的比表面积、比孔容及平均孔径,探讨了炭化条件对其性能的影响。结果表明:随炭化温度的升高和保温时间的延长,炭化竹原纤维的比表面积、比孔容和孔径分布先增大后减小,在较优的工艺条件下,炭化竹原纤维的比表面积和比孔容最大值分别可达819.35m2/g和0.7358cm3/g,平均孔径最小可达2.0836nm。 相似文献