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81.
为比较玉米秸秆揉丝微贮饲料与传统青贮饲料中微生物与营养成分的差异,用常规实验室分析方法对其主要微生物数量及常规饲料营养成分进行了分析测定。结果表明,揉丝微贮饲料中乳酸菌数量比传统青贮饲料多1.54×1012 cfu/g(P<0.05),酵母菌、霉菌、放线菌和细菌的数量则比传统青贮饲料分别少2.21×107 cfu/g、1.23×106 cfu/g、4.12×106 cfu/g和3.11×104cfu/g(P<0.05);揉丝微贮饲料中无氮浸出物、粗纤维、中性及酸性洗涤纤维的含量与传统青贮饲料相比分别降低5.19%、2.34%、1.44%、1.64%,粗脂肪和粗蛋白的含量分别提高5.4%和1.14%,其中粗脂肪、粗纤维和无氮浸出物含量差异显著(P<0.05),粗蛋白、中性洗涤纤维和酸性洗涤纤维含量差异不显著(P>0.05),而水分、粗灰分、钙和磷的含量基本不变。玉米秸秆揉丝微贮与传统青贮饲料相比更优,值得推广。 相似文献
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Apparent digestibility coefficients of processed agro‐food by‐products in European seabass (Dicentrarchus labrax) juveniles 下载免费PDF全文
Apparent digestibility coefficients (ADCs) of processed agro‐food by‐products were assessed in European seabass (Dicentrarchus labrax). Each experimental diet was obtained by replacing 300 g/kg of a commercial‐based diet used as reference (REF) with a test ingredient: wheat germ (GERM), okara meal (OKA), poultry by‐product meal (POULT), steam hydrolysed (FeHY) and enzyme‐treated feather meal (FeENZ), beta‐lactoglobulin (β‐Lg) and peptide fractions >3,000 Da obtained from brewer's yeast (YeastP) and fish by‐products (FishP). Dry matter ADC was highest in β‐Lg (95%) and lowest in OKA (40%). Protein ADCs were high in β‐Lg, FishP, GERM and POULT (>93%); intermediate in FeHY and FeENZ (85%–88%); and moderate in OKA and YeastP (70%–78%). The essential amino acids' ADC mean was above 91% in POULT, β‐Lg, GERM and FishP, 84%–89% in FeHY and FeENZ and 73%–76% in YeastP and OKA. Energy ADC was highest in POULT and β‐Lg (89%–95%) and lowest in YeastP and OKA (61%–64%). Lipid ADC was highest for POULT and GERM (100%). Phosphorus ADC was lowest in GERM (19%) and highest in β‐Lg (88%). FeHY, FeENZ, POULT, GERM, FishP and β‐Lg are highlighted as protein sources for European seabass. 相似文献
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竹提取物的化学成分及其利用研究进展 总被引:4,自引:1,他引:4
近年来,竹类资源的研究和利用在国内外十分活跃.本文综述了竹提取物中的主要化学成分,包括竹叶黄酮、多糖、氨基酸、挥发性成分等的种类和含量研究进展,总结了竹提取物的抗氧化活性等生理功能,重点论述了竹提取物的防腐抗菌作用、控制害虫作用等生物活性.提出了今后竹子化学研究的重点领域. 相似文献
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Zhiqian Lyu Bingbing Huang Zhongchao Li Zhenyu Wang Yifan Chen Shuai Zhang Changhua Lai 《Animal Science Journal》2019,90(1):98-107
The objectives of this experiment were to (a) determine the effects of fiber increase in diets on heat production (HP), (b) determine the net energy (NE) of oat bran (OB), wheat bran (WB), and palm kernel expellers (PKE) fed to growing pigs using indirect calorimetry (IC). Twenty‐four growing barrows (29.2 ± 2.6 kg) were randomly allotted to one of four diets with six replicate pigs per diet. Diets included a corn‐soybean meal basal diet and three test diets containing 30% OB, WB or PKE, respectively. During each period, pigs were individually housed in metabolism crates for 20 days, including 14 days to adapt to the diets. On day (d) 15, pigs were transferred to the open‐circuit respiration chambers for determination of daily total HP and were fed one of the four diets at 2.3MJ ME/kg body weight (BW)0.6/day. Total feces and urine were collected for the determination of digestible energy (DE) and metabolizable energy (ME) and daily total HP was measured from d 15 to d 19 and fasted on day 20 for the measurement of fasting heat production (FHP). The apparent total tract digestibility (ATTD) of dry matter (DM), gross energy (GE), and organic matter (OM) were greater (p < 0.01) in pigs fed the basal diet compared with those fed the test diets. The ATTD of neutral detergent fiber (NDF) was lower (p < 0.01) in pigs fed the WB diet compared with those fed the basal, OB, or PKE diets. The ATTD of ether extract (EE) in pigs fed the PKE diet was greater (p < 0.01) compared with those fed the other diets. The average total HP and FHP in pigs fed the four diets were 1261 and 787 kJ/kg BW0.6/d, respectively, and were not significantly affected by diet characteristics. The NE:ME ratio for diets ranged from 78.1 to 80.9%. The NE contents of OB, WB, and PKE were 10.93, 7.47, and 8.71 MJ/kg DM, respectively. 相似文献
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Zhenyu Wang Yifan Chen Jian Ding Hu Liu Zhiqian Lyu Wenxuan Dong Zijie Wang Shuai Zhang Fenglai Wang 《Animal Science Journal》2019,90(8):939-947
The present study was conducted to determine the net energy (NE) values and energy efficiency of wheat bran (WB), sugar beet pulp (SBP), corn gluten feed (CGF), soybean hulls (SBH), and defatted rice bran (DFRB) fed to pregnant sows. Thirty‐six multiparous pregnant sows were randomly assigned to six dietary treatments with six replicates per treatment. Each period lasted for 21 days including 14 days for adaptation. On day 15, sows were moved into respiration chambers for heat production (HP) measurement and provided feed at 544 kJ/kg BW0.75/day. On day 20, sows were fasted to measure the fasting heat production (FHP). Experimental diets included corn‐soybean meal basal diet and five diets containing 29.20% WB, SBP, CGF, SBH, and DFRB, respectively. Results showed that inclusion of WB, SBP, CGF, SBH, and DFRB to basal diet decreased (p < 0.05) the apparent total tract digestibility of energy and nutrients. The average adjusted total HP and FHP were 418 kJ/kg BW0.75/day and 326 kJ/kg BW0.75/day, respectively. The average NE:ME ratio of experiment diets was 82.5%. In conclusion, the NE values of WB, SBP, CGF, SBH, and DFRB were 9.05, 8.59, 8.37, 7.64, and 7.93 MJ/kg DM, respectively. 相似文献
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为优化烤烟生产技术措施、改善烟叶品质,采用方差分析方法对贵州省紫云县2009—2015年B2F、C3F和X2F等级烟叶的主要化学成分特征变化规律进行分析。结果表明:紫云县烟叶化学成分基本在优质烤烟适宜范围,总体协调性较好。其中,B2F等级烟叶的还原糖含量和两糖比年度间差异显著;C3F等级烟叶的总氮含量年度间差异显著,两糖比年度间差异极显著;X2F等级烟叶的总氮含量年度间差异显著,钾氯比和两糖比年度间差异极显著;中、下部烟叶的总糖、还原糖及钾含量,氮碱比和糖碱比显著高于上部烟叶,总氮及烟碱含量随烟叶部位升高而增加,钾含量、糖碱比、钾氯比和氮碱比随烟叶部位升高而降低。2009—2015年上部烟叶的烟碱含量总体呈下降趋势,下部烟叶略呈上升趋势,中部烟叶较稳定。 相似文献