饲料脂肪水平对胭脂鱼生长性能、肠道消化酶活性和脂肪代谢的影响

试验选用平均体重为(6.73±0.21)g的胭脂鱼(Myxocyprinus asiaticus)幼鱼540尾,随机分成6个组(每组3个莺复,每个重复30尾),分别饲喂脂肪水平为2.04%、4.43%、6.88%、9.02%、11.98%和13.39%的试验饲料,研究脂肪水平对胭脂鱼生长性能、肠道消化酶活性及脂肪代谢的影响.试验期为56 d.结果表明:1)饲料脂肪水平对胭脂鱼的生长性能有显著影响(P＜0.05).当添加量为6.88%时,胭脂鱼增重率、特定生长率和RNA与DNA比值达到最大值,饲料系数达到最小值,二元回归分析确定当增重率和饲料系数达到极值时,饲料脂肪水平分别为6.62%和7.02%,能蛋比分别为45.77和45.96 kJ/g;2)饲料脂肪水平显著影响胭脂鱼肠道消化酶活性(P＜0.05),随着饲料脂肪水平增加,蛋白酶活性逐渐降低,脂肪酶活性先升高后稳定,淀粉酶活性则先降低后稳定,转折点均出现在脂肪水平为6.88%时;3)饲料脂肪水平对脂肪代谢亦有显著影响(P＜0.05),随饲料脂肪水平增加,血清总脂、甘油三酯和总胆固醇含量增加,肝胰脏苹果酸脱氢酶和血清脂蛋白脂酶活性降低.由此得出,胭脂鱼的适宜脂肪水平为6.62%～7.02%,最佳能蛋比为45.77～45.96 kJ/g;饲料脂肪水平增加,使肠道蛋白酶和淀粉晦活性受到抑制,血脂水平增加,脂肪合成代谢酶和脂肪分解酶活性降低.     

饲粮添加硫辛酸对肉鸡生长性能、屠宰性能、脂肪代谢和肠道菌群的影响

本文旨在研究饲粮添加硫辛酸对肉鸡生长性能、屠宰性能、脂肪代谢和肠道菌群的影响。试验选取128只体重相近、健康的14日龄白羽肉鸡,将其随机分为对照组和试验组,每组4个重复,每个重复16只鸡。对照组饲喂基础饲粮,试验组饲喂在基础饲粮的基础上添加400 mg/kg硫辛酸的饲粮。试验期28 d,分为15～28日龄和29～42日龄2个阶段。结果表明：1）与对照组相比,饲粮添加硫辛酸对肉鸡生长性能无显著影响（P>0.05）,但可显著提高肉鸡28日龄屠宰率和42日龄胸肌率（P<0.05）。2)42日龄,与对照组相比,试验组肉鸡腿肌总胆固醇含量和甘油三酯含量显著降低（P<0.05）,而胸肌总胆固醇和甘油三酯含量显著提高（P<0.05）。3)28日龄,与对照组相比,试验组肉鸡盲肠菌群Shannon指数、Simpson指数以及不可培养菌（uncultured）、Shuttleworthia、肠球菌属（Enterococcus）和理研菌属（Rikenella）的相对丰度显著升高（P<0.05）,而盲肠菌群中萨特氏菌属（Sutterella）、Tyzzerella和Harryfl...     

乳化条件对饲用大豆粉末油脂乳化稳定性的影响

为获得最佳的饲用大豆粉末油脂乳化工艺参数,分别进行了乳化剂的配比、乳化剂的含量、乳化温度、乳化时间、壁材比(壳聚糖∶麦芽糊精)和壁材含量6个因素对饲用大豆粉末油脂乳化稳定性的影响的单因素试验。结果表明,各单因素最佳工艺参数分别为:单甘酯与蔗糖酯的质量比1∶9,乳化剂含量1%,乳化温度70℃,乳化时间10min,壁材含量15%,壁材比1∶5。另外,对乳化温度、乳化时间、壁材比和壁材含量的4因素3水平正交试验结果表明,最佳乳化工艺参数组合为乳化温度60℃,乳化时间10min,壁材含量10%,壁材比1∶10。     

镁对草鱼生长和脂肪代谢的影响

本试验在以酪蛋白和明胶为蛋白源的纯化口粮(镁含量76.9 mg/kg)中添加不同水平的镁(0、150、300、600、1 200和2 400 mg/kg),研究了镁对草鱼生长和脂肪代谢的影响.选取540尾体重为(10.68±0.14)g的草鱼,随机分入6个处理,每个处理3个重复,每个重复30尾鱼.进行为期10周的生长试验.结果表明:1)日粮中添加适量镁显著提高草鱼的特定生长率、增重率和饲料效率(P<0.05),当饲料镁含量为692.0 mg/kg时,以上3项指标均达到最大值;2)日粮中添加适量镁能增加草鱼体脂沉积率、血脂水平、肝胰脏脂肪酶和节果酸脱氧酶活性(P<0.05),降低肝胰脏脂蛋白酯酶活性(P<0.05),但对肠道脂肪酶活性没有显著影响(P>0.05).由此可知,日粮中适当添加镁能显著促进草鱼生长,添加量为600 mg/kg(日粮镁含量692.0 mg/kg)时效果最好;镁能够增慢草鱼肝胰脏的脂肪合成能力,降低其脂肪转运能力;镁使肝脂蛋白酯酶活性降低,导致高血脂.     

不同配比油脂对肉鸡脂类代谢的影响

以肉鸡为动物模型,探讨了日粮中添加不同配比油脂后对其脂肪代谢的影响。648只1日龄AA肉仔鸡,随机分为6组,每组6个重复,每个重复18只鸡,试验期为42 d。CON组为对照组(饲喂基础日粮),SO组为正对照组(日粮中添加豆油),LO组为负对照组(日粮中添加猪油),COP、COC、COV组分别在日粮中添加以棕榈油为主的配比油脂、以椰子油为主的配比油脂、多种植物油配比的油脂。结果表明:42 d,各组腹脂重、皮下脂肪厚度与肌间脂肪厚度、胸肌含脂率、腿肌含脂率均无显著性差异(P>0.05);SO、COP组总甘油三酯含量低于COV组(P<0.05);COP组血清低密度脂蛋白胆固醇含量低于LO组(P<0.01)与CON组(P<0.05);COP组血清高密度脂蛋白胆固醇与低密度脂蛋白胆固醇含量的比值高于LO、COC、COV组(P<0.01),SO组显著提高(P<0.05);SO组肉鸡血清中总脂酶活性高于CON组(P<0.05),肝脏中COP、COC、COV组脂蛋白脂酶、肝脂酶与总脂酶活性都显著提高(P<0.01或P<0.05)。结论:配比油脂组与豆油组在不影响脂肪沉积的情况下,改善了肉仔鸡的体脂分布,且对脂质代谢具有很好的调节作用,其中豆油组与以棕榈油为主的配比油脂组效果较好。     

壳聚糖对动物脂肪代谢及生长性能的影响

壳聚糖(chifosan),是甲壳素的衍生物．又名可溶性甲壳素、脱乙酰甲壳素、甲壳胺、几丁聚糖．是通过甲壳素一定程度的脱乙酰而得到．通常将脱乙酰度55％以上的甲壳素称作壳聚糖,化学名称是(1．4)-2-氨基-2-脱氧-β-D-葡聚糖。在众多的天然多糖中,甲壳素及其主要衍生物壳聚糖是唯一的碱性多糖．具有生物相容性、可食用性、可抗菌性、     

植物乳杆菌-泰山松花粉多糖微胶囊对小鼠生长和肠道环境的影响

植物乳杆菌作为微生态饲料添加剂饲喂后易受消化道胃酸、胆汁酸和消化酶等不利因素的影响。泰山松花粉多糖(TPPPS)作为一种水溶性植物多糖也易受到胃酸和酶的破坏。为了保护植物乳杆菌和TPPPS的生物活性,并探索二者之间是否存在协同作用。本研究以植物乳杆菌和TPPPS为芯材制备微胶囊,通过正交试验对包埋工艺进行优化,并对最佳条件下制备的微胶囊进行性能检测。选取体重20 g左右无特定病原体(SPF)小鼠48只,随机分为4组,每组12只。4组小鼠每天分别口服饲喂1 m L的植物乳杆菌、植物乳杆菌+0.5%TPPPS、微胶囊、磷酸盐缓冲液(PBS)。饲养试验42 d。每隔1周各组随机取3只小鼠称重记录,剖检后无菌采集肠道组织,测定小肠绒毛和隐窝发育差异及乳酸菌和大肠杆菌定植情况。结果显示:1)微胶囊包埋率达81.6%,粒径为84.3μm。在模拟胃液中处理120 min植物乳杆菌存活率为62.36%,37℃条件下存储120 d存活率达45.9%。2)与PBS组相比,植物乳杆菌、植物乳杆菌+0.5%TPPPS、微胶囊均能不同程度促进小鼠体重增加,提高小肠中乳酸菌数量,降低大肠杆菌数量,改善小肠绒毛和隐窝发育,微胶囊效果最优。结果提示,植物乳杆菌协同TPPPS使用的益生效果显著优于单独的植物乳杆菌,二者制备的微胶囊能够进一步提高其益生效果。     

谷氨酰胺对早期断奶仔猪生长性能及肠道形态发育的影响

选21日龄断奶的杜大长仔猪72头,按试验要求分为2组,每组3个重复,每重复12头。分别饲喂基础日粮和含1%谷氨酰胺(Gln)日粮,试验期21 d,在断奶后0 d、7 d和14 d分别屠宰取小肠测重,并取十二指肠、空肠、回肠测定绒毛高度和隐窝深度。试验结果表明:断奶后7 d,日粮中添加Gln可显著提高仔猪的平均日增重和小肠相对重量,提高十二指肠和空肠绒毛的高度,降低十二指肠和空肠的隐窝深度;断奶后14 d,日粮中添加Gln对断奶仔猪的生长和肠道形态发育影响与基础日粮组相比差异不显著。     

硫代甜菜碱对肉仔鸡生长性能、胴体品质和脂肪代谢的影响

本试验旨在研究日粮中添加硫代甜菜碱(DMPT)对肉仔鸡生长性能,胴体品质和脂肪代谢的影响.选取360只1日龄健康AA肉仔鸡随机分为6组,每组6个重复,每个重复10只鸡,第1～5组为试验组,分别在基础日粮中添加400、800、1 200、1 600、2 000 mg/kg DMPT,对照组饲喂基础日粮,试验期为42 d.结果表明:与对照组相比,试验组平均日增重(第2～4组)显著升高(P<0.05),料重比(第2～4组)显著降低(P<0.05),屠体重(第3组)显著升高(P<0.05),腹脂率(第1、3组),肌间脂宽(第3组)和皮脂厚(第2～5组)显著降低(P<0.05);胸肌(第3、4组)和腿肌(第3组)肌内脂肪的含量极显著升高(P<0.01);血清甘油三酯(第3组)、胆同醇(第2、3组)的含量显著降低(P<0.05),游离脂肪酸的含量(第3、4组)、腹脂激素敏感脂肪酶(第2、3组)和血清脂肪酶(第3、4组)活性显著升高(P<0.05).可见,DMPT可促进肉仔鸡生长,改善胴体脂肪分布,而胴体脂肪分布的变化可能与脂肪酶活性的变化有关.     

抗菌肽高表达量黄粉虫对肉鸡生长性能、肠道菌群和小肠绒毛形态的影响

为探讨抗菌肽高表达量黄粉虫对肉鸡生长性能、肠道菌群和小肠绒毛形态的影响。试验以玉米和豆粕为主要原料配制饲粮,试验采用单因子随机区组设计,选择1日龄雌雄各半、体质量相近、健康的爱拔益加（AA）肉鸡300只,测体质量后随机分为3个组,分别为对照组、黄粉虫未诱导组和黄粉虫诱导组,每组5个重复,每个重复20只鸡。对照组饲喂基础日粮,未诱导组和诱导组分别用未诱导和诱导的2%黄粉虫粉等量替代基础日粮中的鱼粉。试验期42d。结果显示,各组肉鸡的日采食量差异均不显著（P=0.559）,黄粉虫诱导组日增重极显著高于对照组和黄粉虫未诱导组（P=0.005）,而料肉比极显著低于对照组和黄粉虫未诱导组（P〈0.000 1）。黄粉虫诱导组大肠杆菌数量极显著低于对照组和黄粉虫未诱导组（P〈0.000 1）,各组肉鸡乳酸杆菌数量在21目龄差异不显著（P=0.191）,42日龄差异显著（P=0.034）。添加抗菌肽高表达量的黄粉虫极显著提高十二指肠、空肠和回肠小肠绒毛的长度（P〈0.000 1）和绒毛长度与隐窝深度的比值（P〈0.000 1）,各组肉鸡的隐窝深度差异不显著,但呈诱导组〈未诱导组〈对照组的趋势。结果表明,抗菌肽高表达量黄粉虫能够提高肉鸡的生长性能,降低肠道中大肠杆菌数量,促进肠道中乳酸杆菌繁殖,改善小肠绒毛形态。     

Effects of soybean oil and dietary copper on ruminal and tissue lipid metabolism in finishing steers

An experiment was conducted to determine the effects of Cu and soybean oil (SBO) supplementation on ruminal and tissue lipid metabolism and carcass characteristics in finishing steers. Sixty Angus steers (369.0 +/- 10.1 kg) were stratified by weight and randomly assigned to treatments in a 2 x 2 factorial arrangement, with factors being 0 or 20 mg of supplemental Cu/kg DM from Cu sulfate and 0 or 4% SBO. Steers were fed a high-concentrate basal diet that contained 5.3 mg Cu/kg DM. Average daily gain and feed intake were reduced (P < 0.01) by SBO but were not affected by Cu. Gain:feed ratio was not affected by treatment. Liver Cu concentrations were higher (P < 0.01) in steers receiving supplemental Cu and lower (P < 0.04) in SBO-supplemented steers. Copper supplementation tended to reduce (P < 0.12) and SBO supplementation tended to increase (P < 0.11) serum cholesterol concentrations. Backfat depth was reduced (P < 0.10) by Cu and SBO supplementation. Marbling scores and longissimus muscle lipid content were not affected by Cu supplementation; however, SBO supplementation reduced (P < 0.01) marbling scores. Longissimus muscle polyunsaturated fatty acids tended to be increased (P < 0.14) in Cu-supplemented steers. Longissimus muscle C18-conjugated dienes and the 18:1 trans isomer were increased (P < 0.05) in SBO-supplemented steers. Ruminal fluid 18:3 was increased (P < 0.05) and the 18:1 trans isomer was decreased (P < 0.05) in Cu-supplemented steers. These results indicate that as little as 20 mg of supplemental Cu/kg DM can reduce backfat and may alter lipid metabolism in steers fed high-concentrate diets.     

Effects of glucocorticoids on parameters of lipid metabolism, hepatic metabolism, haematological parameters and milk yield in high-yielding cows in early lactation

Effects of glucocorticoids on lipid metabolism, hepatic metabolism, haematological parameters and milk yield in high-yielding cows in the early stages of lactation. The assumption is widespread that glucocorticoids promote lipolysis and fatty liver in ruminants. But there are contrary experimental results. Therefore we investigated the effects of dexamethasone (in the form of Voren suspension) in cows with very high milk yields (herd average 10.000 kg/year) between 7 and 15 days post partum, when high levels of lipolysis occur. Nine cows were given Voren 7 and 11 days post partum at doses of 0.02 mg/kg body weight. Glucose and insulin concentrations rose whilst FFA concentrations fell. Hepatic lipid levels were unchanged compared to a control group (n=8). There were also no changes in the various liver function parameters tested (beta-hydroxybutyrate, bilirubin, cholesterol, albumin, aspartat-amino-transferase, glutamat-dehydrogenase), which suggests that liver damage did not occur. Each of the two doses of Voren resulted in typical glucocorticoid-related changes in the differential leukocyte count. There was only a very slight reduction in daily milk yield. This studies show that, in ruminants, glucocorticoids have an indirect antilipolytic effect in vivo and do not aggravate or accelerate fatty degeneration of the liver.     

Effects of dietary essential oil components on growth performance,digestive enzymes and lipid metabolism in female broiler chickens

1. The present experiment was conducted to describe the effects of thymol, cinnamaldehyde and a commercial preparation of essential oil components (CRINA Poultry), in female broilers. Feed and water were provided for ad libitum consumption. 2. Feed intake, weight gain and feed:gain ratio were not different among the treatments. Water intake was significantly lowered by cinnamaldehyde. Relative liver weight (g/100 g of body weight) was highest in birds given thymol, but this was seen only at the age of 21 d and not at 40 d. Patterns of digestive enzymes in pancreatic tissue were similar for the 4 treatments. 3. Amylase activity in intestinal digesta was highest in chickens given CRINA Poultry for 21 d, but the effect had disappeared after 40 d. Ileal digestibility coefficients for starch and protein were high and identical for all treatments. 4. Fatty acid composition of diet was reflected in that of adipose tissue. Plasma lipid concentrations were not changed by any dietary treatment. 5. Thus, the present results show no effect of essential oil constituents on growth performance in female broiler chickens, but it cannot be excluded that positive effects would have been observed under less hygienic environmental conditions or when using a less digestible diet.     

中草药方剂对肉仔鸡脂类代谢的影响

选取225只1日龄艾维茵肉鸡,随机分为5组,每组3个重复,每个重复15只鸡,研究中草药方剂对肉仔鸡脂类代谢的影响。基础日粮为玉米-豆粕型,对照组饲喂基础日粮,试验组分别在基础日粮中添加0.5%、1.0%、1.5%、2.0%的中草药复方添加剂,进行为期6周的饲养试验。结果表明:日粮中添加该方剂显著影响了肉仔鸡血液中总胆固醇(TC)、甘油三酯(TG3)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C)的含量,且随着中草药添加水平的升高,TC、TG3、LDL-C含量有下降的趋势,而HDL-C则显著升高,并且能显著降低腹脂率、肝脂含量和肌肉中胆固醇含量。     

大豆低聚糖对蛋鸡脂质代谢和抗氧化能力的影响

选择240只34周龄的健康商品代海兰褐壳蛋鸡,随机分为4组,每组3个重复,每个重复20只鸡,分别在其日粮中添加0%、0.1%、0.2%和0.3%的纯度为30%的大豆低聚糖,探讨其对产蛋高峰期蛋鸡脂质代谢和抗氧化能力的影响.试验期为56 d.结果表明:添加大豆低聚糖可以降低蛋鸡血清中总胆固醇(T-CHO)(P<0.05)、甘油三酯(TG)(P>0.05)和低密度脂蛋白胆固醇(LDL-C)水平(P<0.05),提高高密度脂蛋白胆固醇(HDL-C)水平(P<0.05),以0.30%添加组效果最好;添加大豆低聚糖可以提高蛋鸡血清中超氧化物歧化酶(SOD)含量(P<0.05),降低丙二醛(MDA)含量(P>0.05).     

In vitro study of effects of emulsified oil on broiler feed quality

An experiment was conducted to compare effects of emulsified soybean oil and non‐emulsified soybean oil on the quality of broiler feed differing in the feed type and the broiler feeding stage in vitro. A 2 × 2 × 3 factorial arrangement was designed with two fat sources (soybean oil and emulsified oil), two feed types (mash and pellet) and three broiler feeding stages (starter, grower and finisher). Four samples of feeds were collected from each combination of factors at the beginning of the experiment and stored at 20°C. Subsamples were taken at 15‐day intervals to determine the moisture content, peroxide value (PV), acid value (AV) and the total fungal count over a 45‐day period; weight loss percentage was determined by weighting the samples at days 0, 15, 30 and 45; fines percentage in pellets was only determined at day 0. The emulsified oil reduced (P < 0.05) the fines percentage, increased (P < 0.05) the moisture content, decreased (P < 0.05) the weight loss percentage and PV, did not affect (P > 0.05) the AV and the total fungal count. Results showed that the emulsified oil decreased weight loss, increased pelletability, moisture content and oxidation stability without affecting fungal growth.     

壳聚糖对肉仔鸡脂肪代谢的影响

本试验选用了体重相近的健康的1日龄AA肉公仔鸡96只,随机分成4组,每组设4个重复,每个重复6只鸡。试验期为21d。在各组基础饲料中分别添加0、50、100、150mg/kg的壳聚糖。结果表明:150mg/kg组壳聚糖对肉仔鸡脂类代谢的影响效果显著,能分别降低肉仔鸡的肝脂率和腹脂率4.92%(P0.05)和16.67%(P0.05),同时能有效降低血清中胆固醇水平23.19%(P0.05),肉仔鸡腹脂脂肪酶合成酶(FAS)和苹果酸酶(ME)活性没有影响,但肉仔鸡腹脂脂蛋白酯酶(LPL) mRNA表达显著性上调(P0.05)。     

多不饱和脂肪酸对脂肪代谢酶基因表达的影响

多不饱和脂肪酸不仅可以抑制脂肪合成酶基因的表达,还能对脂质氧化相关酶基因的表达起促进作用,从而调节机体脂质代谢过程。本文主要就多不饱和脂肪酸的分类和来源、对脂肪合成及氧化相关酶基因表达的影响作一综述。     

Effects of endotoxin on carbohydrate metabolism in inbred mice.

Effects of endotoxin on carbohydrate metabolism were studied in A/HeJ (endotoxin-sensitive) and C3H/HeJ (endotoxin-resistant) inbred mice. A/HeJ mice developed hypoglycemia within two hours after endotoxin injection, yet liver glycogen content did not differ from controls. Similarly treated C3H/HeJ mice did not develop significant hypoglycemia. Administration of glucagon to endotoxin-treated A/HeJ mice failed to elevate their blood glucose concentrations, while endotoxin-treated mice of the same strain did respond to dibutyryl cyclic AMP with a significant elevation of blood glucose. C3H/HeJ mice on the other hand responded to glucagon and dibutyryl cyclic AMP with elevated blood glucose. Endotoxin-treated C3H/HeJ but not A/HeJ mice were able to carry out gluconeogenesis induced by prednisolone, while both inbred strains showed active glycogenesis after administration of an exogenous glucose load. Administration of glucagon resulted in diminished liver glycogen concentrations in A/HeJ endotoxin-treated mice suggesting no impairment of glycogenolysis. The inability of endotoxin-treated A/HeJ mice to respond to glucagon could be due to impairment of gluconeogenesis. Although endotoxin interfered with the capacity of both inbred strains to respond to glucagon administration with elevation of liver cyclic AMP, the effect was significantly more severe in A/HeJ mice. The susceptibility of A/HeJ mice to the lethal effect of endotoxin may be related to the apparent sensitivity of carbohydrate metabolic pathways to disturbance by endotoxin.