盐度和饲料蛋白对凡纳滨对虾营养及消化作用研究进展

不断增加的水产品需求与缺乏可持续发展的捕捞业之间的矛盾日益凸显,为改善水产品供应短缺的问题,发展水产养殖业十分重要。随着水产养殖业集约化和规模化的发展,水环境逐步恶化,应激因素逐渐增多,严重阻碍对虾养殖业的发展。因此,寻找绿色健康、安全高效、节约减排的养殖模式已成为热点研究问题。蛋白质是生命的物质基础,饲料蛋白是对虾饲料中最主要的营养成分。盐度是影响对虾生理反应的重要因子,不同盐度下凡纳滨对虾表现出不同的适应状态。对盐度和饲料蛋白在凡纳滨对虾生长、存活、营养需求、消化代谢以及健康免疫等方面发挥作用的相关国内外研究结果进行综述,明确提出凡纳滨对虾在不同盐度的养殖水体中蛋白需求量有所不同,指出在当前对虾饲料中普遍使用盐度参数缺乏蛋白含量的背景下,水体盐度对凡纳滨对虾的作用应受到关注。最后,对今后养殖凡纳滨对虾水体盐度与营养需求的研究方向以及对虾饲料的开发前景进行展望。     

Digestion of microbial biomass, structural polysaccharides, and protein by the humivorous larva of Pachnoda ephippiata (Coleoptera: Scarabaeidae)

In order to investigate whether microbial biomass and its residues are nutrient and energy sources for humivorous beetle larvae, we carried out feeding trials using soil supplemented with ¹⁴C-labeled fungal biomass (Penicillium chrysogenum), bacterial biomass (Bacillus megaterium), fungal or bacterial structural polysaccharide (chitin, peptidoglycan), bacterial protein, or cellulose, taking the larva of the cetoniid beetle Pachnoda ephippiata (Coleoptera: Scarabaeidae) as a model of a humus-feeding beetle larva with a highly alkaline gut. The results showed that gut passage strongly stimulated the mineralization of the structural polymers. The stimulatory effect correlated positively with the recalcitrance of the preparation in the control soil, and was accompanied by a transformation of the residual radiolabel to alkali-soluble and acid-soluble products. The solubility increase was highest in the extremely alkaline midgut. High-performance gel-permeation chromatography demonstrated that the changes in solubility were accompanied by reciprocal changes in the molecular weight of the residual material and that the residual material in the fecal pellets was more humified than in the control soil. The amount of radiolabel recovered from the body and hemolymph of the larvae indicated that microbial biomass and its structural components were assimilated more efficiently than cellulose, which supports the hypothesis that microorganisms and the nitrogenous components of humus are an important dietary resource for humivorous soil macroinvertebrates.     

饲喂不同日粮河麂的蛋白质表观消化率研究

[目的]检验在河麂饲料中添加高蛋白饲料的必要性。[方法]2013年在南京市红山森林动物园进行河麂的消化代谢试验,对不同蛋白水平的饲料进行蛋白质表观消化率的测定。[结果]饲喂普通日粮的对照组蛋白质表观消化率为74.01%,饲喂添加大豆的高蛋白日粮的试验组蛋白质表观消化率为68.69%。这说明蛋白质消化率随着日粮蛋白水平的提高而降低。经1年的饲养实践发现添加大豆使河麂种群死亡率下降5%,受孕率增加2.66%,幼崽成活率增加19.26%。[结论]该研究可为配制更加合理的河麂饲料配方提供依据。     

稻草补饲不同水平苜蓿对山羊能量消化代谢的组合效应研究

将9只体况良好、体重相近的成都麻羊半同胞羯羊,随机分成3组,饲以稻草基础日粮,分别补饲25％（MSL25）、50％（MSL50）与75％（MSL75）的苜蓿（MSL）,采用单因子试验设计,研究稻草补饲苜蓿对山羊能量消化代谢的影响。结果：总能（GE）的消化率与代谢率自高到低的排序均为MSL75〉MSL50〉MSL25,其相应值分别为58．92％、54．48％与51．12％,48．42％、44．87％与41．85％,除MSL75与MSL25外（P〈0．05）,其余组间差异不显著（P〉0．05）。消化能（DE）转化为代谢能（ME）的效率自高到低排序为MSL50（82．36％）〉MSL75（82．18％）〉MSL25（81．86％）,组间差异不显著（P〉0．05）。说明山羊稻草基础日粮补饲50％MSL的能量利用效率最佳,表现出明显的组合效应。     

玉米秸秆及青贮饲料的细胞壁成分体外消化性能比较

利用体外消化试验法，对吉单4011和四单29两品种玉米的秸秆和青贮饲料进行了干物质和细胞壁成分的消化率和消化速度常数的测定，吉单4011的干物质（DM）和细胞壁成分（OCW）的有效消化率分别是57．4％和48．9％，吉单29分别是58．8％和53．9％。两品种玉米青贮饲料OCW的消化速度常数显著高于秸秆，吉单4011的秸秆和青贮饲料分别是4．85％和4．52％，吉单29分别是5．81％和7．11％。结果表明，通过青贮，可以提高玉米秸秆细胞壁的消化率和消化速度常数，秸秆中OCW含量高的玉米品种更适合青贮。     

Utilization of nutrients as influenced by different restriction levels of feed intake under sub-tropical conditions in crossbred calves

Twenty growing crossbred calves (mean body wt. 159.7 ± 3.94 kg) were randomly divided into 4 groups 5 in each following randomized block design. To assess the voluntary dry matter intake (VDMI) during preliminary feeding period, all the animals were fed concentrate mixture and wheat straw ad libitum. The lowest DMI amongst all animals fed ad libitum was defined as ‘VDMI’. The animals were fed at four fixed levels. The highest level of DMI was 95% of VDMI (group 1) as determined in preliminary period of feeding the other 3 levels were 80% (group 2), 60% (group 3) and 40% (group 4) of the VDMI. The experimental feeding was continued for a month followed by a metabolism trial. The dry matter intake through concentrate (crushed maize 33, deoiled-soya meal 32, wheat bran 32, mineral mixture 2 and common salt 1 part) and roughage (wheat straw) was 40:60. The DMI (kg/d) and percent of body weight ranged from 1.62 (group 4) to 4.06 (group 1) and 1.20 to 2.58, respectively. The CP intake (g/d) varied from 177 to 442 among 4 groups. The intake of DM, OM, CP, EE, NDF, ADF and hemi-cellulose (g/d or g/kg w^0.75) was also significantly (P < 0.05) different among 4 groups. The digestibility of DM in groups 1, 2, 3 and 4 was 59.9, 61.7, 64.6 and 30.4%, respectively and was significantly (P < 0.05) lower in group 4 as compared to the remaining 3 groups. The digestibility of other all nutrients viz. OM, CP, EE, NDF, ADF and HC was comparable among groups 1, 2 and 3. However, the digestibility of these nutrients was significantly (P < 0.05) lower in group 4 (40% intake) as compared to the other 3 groups. Intake and balance of N was significantly (P < 0.01) different among 4 groups, being the lowest in group 4. Animals of groups 1, 2 and 3 were in positive nitrogen balance, however, animals of group 4 were in negative N balance. The results revealed that nutrient utilization was unaffected up to 60% level but it was drastically reduced at 40% level of feed intake. It was also observed that calves maintained on 80 and 60% of feed intake lost body weight (250–300 g/d).     

不同日粮养分在绵羊体内消化量的研究

用装有永久性瘤胃、十二指肠和回肠瘘管羊测定蛋白质含量为 13 63 %、14 67%和 16 96%三个水平日粮在胃肠道各部位的食糜流通量和消失率。结果表明 :蛋白质含量多的日粮消化率高。瘤胃中干物质消化量比小肠高     

大豆蛋白中抗原物质的研究进展

自发现大豆蛋白中抗原物质可引起幼龄动物发生过敏以来,大豆抗原的研究受到广大学者所关注.在某种程度上,它们的存在影响了大豆的营养价值,从而限制了其广泛利用.本文综述了大豆抗原分离提纯与有效加工灭活的方法,以及大豆抗原在仔猪、犊牛和鼠体内抗营养作用及消化动力学的研究进展,为进一步完善其致敏机理提供科学参考.     

半胱胺对绵羊消化代谢的影响

十二指肠灌注半胱胺后，４头湖羊平均日采食量（以ＤＭ计）虽无显著性变化，而由复胃进入十二指肠的食糜流量则增加１５．８１％（Ｐ〈０．０５）；食糜ＴＮ流量由１８．３４±０．４２ｇ／ｄ提高到２１．３４±０．５８ｇ／ｄ（Ｐ〈０．０１），其中ＭＣＰ－Ｎ及表观过瘤胃蛋白氮（ＢＰＮ）分别提高２８．５７％（Ｐ〈０．０５）和１４．４４％（Ｐ〈０．０５）。瘤胃液总脱氢酶活力平均提高２１．１５％（Ｐ〈０．０２５），ＮＨ３     

不同处理方法提高反刍动物对粗饲料纤维消化力的机理研究

由于哺乳动物消化腺分泌的淀粉酶不能作用于纤维β-1,4-糖苷键,因此其本身不能直接利用纤维,加之细胞壁结构独特性,这是限制纤维消化的根本原因。真菌和细菌能分泌纤维素分解酶,故在动物消化道内共生的微生物中有许多纤维素酶可以起作用。在保障反刍动物体质和生产性能不下降的情况下,运用科学、合理的处理方法增加反刍动物饲料日粮中纤维消化率是有效降低畜牧养殖业生产成本,充分利用粗饲料资源的有效途径。