茶多酚对朗德鹅产肝性能和血清脂类成分的影响

采用单因素试验设计方案。将14周龄、体重相近的健康公朗德鹅150只随机分成5组,每组30只,每只一个重复。对照组饲喂基础日粮,试验组在基础日粮基础上分别添加40、80、160、320mg/kg茶多酚,以研究茶多酚对朗德鹅产肝性能和血清脂类成分的影响。试验结果表明,1)160mg/kg添加组肥肝重、肝屠比,与对照组和320mg/kg添加组均差异显著(P<0.05),肝体比与对照组和320mg/kg添加组差异均显著(P<0.01)。2)320mg/kg添加组血清甘油三酯含量(TG)与对照组和其他试验组差异均显著(P<0.05);320mg/kg添加组血清总胆固醇含量(TC)与对照组差异均显著(P<0.05),与其他试验组差异不显著(P>0.05);高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C)各组差异均不显著(P>0.05)。试验结论:在玉米型日粮添加40￣160mg/kg均能提高朗德鹅产肝性能,添加160mg/kg茶多酚朗德鹅产肝性能最佳,添加320mg/kg茶多酚能显著降低血清TG和TC含量。     

添加不同脂肪酸对填饲朗德鹅产肝性能、屠宰性能及体脂沉积的影响*

将14周龄、体重相近的健壮朗德鹅120只随机分成6组,每组20只,以玉米作为主要填饲饲料。试验组在对照组日填饲量的基础上分别添加一定量的脂肪酸：6％葵花籽油（葵花籽油组）、6％菜籽油（菜籽油组）、6％牛油（牛油组）、3％鹅油（鹅油Ⅰ组）、2％鹅油（鹅油Ⅱ组）。试验结果表明：添加脂肪酸能影响填饲朗德鹅的产肝性能,其中以葵花籽油效果最好,肝重是对照组的1．37倍,差异显著（P〈0.05）,牛油使填饲朗德鹅产肝下降。添加油脂组对屠宰性能影响不如产肝性能影响明显,菜籽油组在试验中屠宰性能最好且腹脂沉积能力最强,与对照组相比差异显著（P〈0.05）,但是添加脂肪酸组之间差异不显著（P〉0.05）。     

朗德鹅的屠宰、取肝及加工

朗德鹅在填饲结束后,填饲成熟的鹅要送到屠宰场集中宰杀取肝。屠宰前的肥肝鹅要停食12～18小时,但要供给充足的饮水。如用车辆运输,应把鹅放在运输笼中,每笼放鹅4只,笼里要多铺垫草。决不能将肥鹅放在车斗中运输,否则车子启动后,肥鹅堆集一起,会造成大批死亡。车辆的颠簸也会使鹅腹腔的肥肝受损淤血。因此,无论装车还是卸车,操作都要轻捉轻放,避免一些不必要的损失。     

朗德鹅与籽鹅、莱籽鹅杂交的产肝性能观察

随机选择朗德鹅与籽鹅、莱籽鹅的杂交鹅雏各50只,待养至4月龄后达成年体重时,每组选择20只,进行为期3～4周的填饲试验。测量填饲肥肝平均重、平均耗料量和肝料比。结果表明：朗德×菜籽鹅的平均肝重为669．00g,极显著高于朗德×籽鹅（P〈0．01）,较朗德×籽鹅、菜籽鹅与籽鹅分别提高了163．09g、289．00g和365．85g,即分别提高了32．24％、76．05％和120．68％;同时降低了单位肥肝的饲料消耗量,肝料比为1：33．71。因此,从肥肝重和耗料上综合评价得出,朗德×菜籽鹅组的填饲效果最佳,是生产肥肝最好的杂交组合。     

朗德鹅A-FABP基因内含子2多态性及其与产肝性能的关联分析

采用PCR-SSCP法检测77只朗德鹅A-FABP基因内含子2的多态性,并对基因多态性与肥肝性能进行关联分析。结果表明:扩增序列大小为482 bp,发现有2个突变位点,在162 bp处发生T→C突变,在322 bp处发生C→T突变,鹅群中表现出AA、AB和BB 3种基因型,且基因型频率分别为0.1948、0.5455、0.2597,A和B等位基因基因频率分别为0.4676、0.5324,群体该多态位点处于Hardy—Weinberg遗传平衡状态。单因素方差分析显示,AB型个体的肝重和肝体比均最高,其中AB、AA型个体肝体比差异显著(P<0.05),AB、BB型个体肝重差异显著(P<0.05)。初步推断,A-FABP基因可作为影响朗德鹅产肝性能的候选基因,其中基因型AB为有利基因型。     

维生素E对朗德鹅产肝性能的影响及其经济效益分析

采用单因子设计方案,将360R70日龄同批孵化、体重相近、健康的朗德鹅随机分成4组,其中Ⅰ组为对照组,Ⅱ组、Ⅲ组、Ⅳ组为试验组;每组均90只,组内3个重复.Ⅰ、Ⅱ、Ⅲ、Ⅳ组在超饲养饲粮基础上分别添加0、70、140、210IU/kg的维生素E,研究不同水平的维生素E对朗德鹅填饲后的屠宰性能和产肝性能的影响.试验结果:①试验组与对照组之间朗德鹅的各项屠宰性能指标差异不显著(P>0.05);②试验组中的平均肝重和填成率均高于对照组,Ⅲ组最高,差异显著(P<0.05);Ⅲ、Ⅳ组的料肝比显著低于Ⅰ、Ⅱ组(P<0.05);③试验组与对照组相比,每只鹩分别增收1.86、4.79、2.02元,Ⅲ组增收最高.     

填饲对朗德鹅血液指标、组织营养成分以及肝脏组织学的影响

通过对6只110日龄朗德鹅进行高能饲料填饲,测定和观察血清生化指标、肝脏、胸肌和腿肌中营养成分和肝脏组织学变化。结果显示,填饲20d后鹅肝脏重量显著提高(P0.01),血清中谷丙转氨酶、谷草转氨酶、甘油三酯、总胆固醇和高密度脂蛋白水平显著增加(P0.01),其中γ-谷氨酰转肽酶在填肥过程中呈现出先升高后降低,与人类肝脏酶学研究结果一致;脂肪主要在肝脏沉积,其他组织无明显差异,蛋白质在肝脏中相对增加;填饲朗德鹅肝脏细胞胀大,肝细胞胞浆中充满大量大小不等的脂肪滴。这些结果为鹅生理和病理研究、肥肝生产及其遗传选育提供基本参考。     

不同开填体重朗德鹅产肝性能的比较试验

对不同开填体重的朗德鹅产肝性能进行了比较分析。结果发现:4.2 kg体重组的平均肝重最大,为827.50 g,极显著高于3.8 kg、3.0 kg体重组(P<0.01);4.7 kg体重组的肝重明显低于4.2 kg体重组,但没有达到显著水平(P=0.20);相关分析发现开填体重与肝重之间呈极显著的正相关;通过建立回归曲线得出国内朗德鹅12周龄的最佳开填体重为4.5 kg。对肥肝重与腹脂重、皮脂厚等指标进行了相关性分析,发现肝重与腹脂重呈正相关且达到显著水平(P<0.05),说明脂肪组织的脂肪沉积与肝脏的脂肪沉积有密切的关系。     

日粮营养对动物脂肪组织基因表达的影响

脂肪组织是一个强大的分泌器官,它能分泌许多与能量、脂肪代谢相关的酶、激素等.调控能量代谢和脂肪组织生长.本文综述了日粮对动物脂肪组织中基因表达作用的研究状况.并阐述了营养成分对这些基因上下游表达的作用机制.     

Decrease in stearic acid proportions in adipose tissues and liver lipids in fatty liver of dairy cows

Samples of liver and perirenal, mesenteric and subcutaneous fat were collected from 16 sick necropsied dairy cows to evaluate the fatty acid profiles in the hepatic and adipose tissues associated with advanced fatty liver or hepatic lipidosis. Hepatic triglyceride and eight fatty acids were measured in the hepatic and adipose tissues. Six cows had more than 3% triglyceride on fresh weight in their livers and were classified as having fatty liver. Stearic and linoleic acid proportions in the liver decreased markedly with increased hepatic triglyceride levels, while the proportion of palmitic and oleic acids increased. The most striking fluctuations in hepatic lipidosis were manifested as decreased stearic acid in the adipose tissues including subcutaneous fat with the trend of decreasing stearic acid. Palmitic acid was elevated in hepatic and perirenal fat in fatty liver cows. In instances of advanced hepatic lipidosis, palmitoleic acid increased in only subcutaneous fat and not in perirenal or mesenteric fat. In addition to the proportions of hepatic fatty acids in fatty liver, this study also clarified the fluctuations observed in the profiles of fatty acids of the adipose tissues in cows with advanced hepatic lipidosis, particularly the decline in the proportions of stearic acid.     

Effects of a high energy and low protein diet on hepatic and plasma characteristics and Cidea and Cidec mRNA expression in liver and adipose tissue of laying hens with fatty liver hemorrhagic syndrome

Cidea and Cidec are two members of Cell death‐inducing DNA fragmentation factor‐alpha‐like effector family proteins, which could be involved in lipid or fat metabolism. To better understand the roles of Cidea and Cidec in fatty liver hemorrhagic syndrome (FLHS), 150 healthy 155‐day‐old Hyline Brown laying hens were randomly divided into control group (fed with basic diet) and experimental group (fed with high‐energy low‐protein [HELP] diet). Analysis of the liver by tissue sectioning and hematoxylin and eosin staining showed that the HELP diet induced micro‐vesicular steatosis in laying hens. Subsequently, based on the liver color scores and the range of lipid accumulation observed in histological examination, we classified livers with <50% vacuolization as mild FLHS and >50% as severe FLHS. The results showed that the levels of Cidea and Cidec mRNA expression were markedly elevated in the liver and adipose tissues with FLHS and the levels of Cidea and Cidec mRNA expression in the liver with severe FLHS were significantly higher than that in the liver with mild FLHS. Thus, the present study revealed that the Cidea and Cidec genes may be involved in pathways of FLHS formation.     

Complement C3 participates in the development of goose fatty liver potentially by regulating the expression of FASN and ETNK1

Non-alcoholic fatty liver disease ( NAFLD ) occurs in humans, domestic animals and poultry. Different from upregulation of complement C3 in human NAFLD, C3 expression is inhibited in goose fatty liver ( GFL ), implying a specific role of C3 in GFL. This study was mainly focused on uncovering the uniqueness of goose liver cells in the regulation of C3 expression and identifying the downstream genes of C3 to improve understanding on the specific role of C3 in GFL. The results showed that C3 expression was inhibited in the liver, muscle and fat tissues of the overfed versus control (normally fed) geese. Oleate and insulin could inhibit C3 expression in goose primary hepatocytes but induce it in mouse primary hepatocytes. A total of 1,123 differentially expressed genes ( DEGs ) were affected by C3 overexpression and were mainly enriched in immune response/inflammation and catabolism-related KEGG pathways. Additionally, the representative downstream genes (FASN and ETNK1) of C3 could mediate the role of C3 in the development of GFL. In conclusion, the suppression of C3 in GFL is at least partially attributed to hyperinsulinemia, hyperlipidemia and uniqueness of goose liver cells. Complement C3 does not only affect hepatic steatosis but also affect inflammation/immune response in GFL.     

Effect of ruminal dosing of mechanical stimulating brush on carcass characteristics and fatty acid composition of dressed carcass fat in fattening Holstein steers fed with high-concentrate diets

This experiment was undertaken to examine the effect of dosing of a mechanical stimulating brush (RF) in the rumen on dressed carcass characteristics and on the fatty acid composition of dressed carcass fat in fattening beef cattle. The fattening trial was carried out with high-concentrate diets (organic cell wall contents: 27.5% on a dry mater basis) in eight Holstein steers (12 months of age). Four of the experimental animals were orally dosed with three RF/head (RF group); the other four animals without RF dosing were allotted as the control group. Grass hay was fed to the animals (0.2 kg/head/day) until 19 months of age. Concentrate diet was given ad libitum during the experiment. There were no statistical differences between the RF group and the control group in yield score and meat quality score of dressed carcass characteristics. Regarding fatty acid composition of dressed carcass fat, the proportion of C18 : 2 fatty acids in subcutaneous fat in the RF group was greater ( P  < 0.05) than that in the control group. C16 : 0 fatty acids in kidney fat in the RF group was lower ( P  < 0.05), and C18 : 2 fatty acids and total unsaturated fatty acids of 18 carbon number in kidney fat in the RF group were higher ( P  < 0.05) compared with the control group. The proportion of C18 : 2 fatty acids in rib eye fat in the RF group was greater ( P  < 0.05) than that in the control group. C18 : 1 fatty acids, C18 : 2 fatty acids and total unsaturated fatty acids of 18 carbon number in rib fat in the RF group were greater ( P  < 0.05) than those in the control group. The results suggest that in fattening Holstein steers fed with high-concentrate diets, the effect of ruminal RF dosing on dressed carcass characteristics is not significant, but the proportion of unsaturated fatty acid of carcass fat is increased.     

Effects of animal liver and bile extracts on biochemical values of rat ethanol‐induced fatty liver

The purposes of this study were to assess the improvement of fatty liver induced by ethanol with animal liver and bile extracts. This research aimed to increase the economic values of animal liver and bile extracts and used these to reduce damage of ethanol‐induced fatty liver. Extracts came from animal liver and bile, including pig bile powder, pig liver extract, a mixture of pig bile powder and pig liver extract, chicken bile powder, chicken liver extract, and a mixture of chicken bile powder and chicken liver extract, and these were fed to Long‐Evans rats. The results showed that rats fed ethanol for long terms could increase values of aspartate transaminase, cholesterol, γ‐glutamy‐transferase and alkaline phosphatase. Pig bile powder could decrease the values of aspartate transaminase, cholesterol and γ‐glutamy‐transferase. The significances also decreased on aspartate transaminase, γ‐glutamy‐transferase and aspartate transaminase, which were carried out with the pig liver extract treatment. These results suggest pig bile and liver extracts have high potential to improve rats' ethanol‐induced fatty liver with serum biochemical parameters.     

日粮中添加脂肪酸钙对奶牛生产性能的影响

选取24头处于泌乳前期的中国荷斯坦奶牛,采用配对设计分成4组,研究奶牛日粮中分别添加200g棕榈油脂肪酸钙、大豆油脂肪酸钙和葵花籽油脂肪酸钙对奶牛采食量、产奶量及乳品质的影响。结果表明:日粮中添加3种脂肪酸钙均不影响奶牛采食量(P>0.05);添加棕榈油脂肪酸钙后产奶量提高10.45%、乳脂率提高7.42%、乳蛋白率降低4.67%、乳干物质提高1.41%(P>0.05);添加大豆油脂肪酸钙后产奶量提高4.25%、乳脂率提高8.54%、乳蛋白率降低4.64%、乳干物质提高2.67%(P>0.05);添加葵花籽油脂肪酸钙后产奶量提高4.76%、乳脂率提高3.52%、乳蛋白率降低3.35%、乳干物质提高1.42%(P>0.05)。     

填饲饲粮对水禽肥肝形成的影响

甘油三酯(triglycerides,TG)的沉积可能是水禽肥肝形成的重要原因,而很多因素均与TG的积累密切相关。本文从水禽肥肝组织学特征、肝脏内脂肪酸代谢途径以及不同营养素对肥肝脂肪代谢的影响方面,详细综述了肥肝形成的可能机制及最新研究进展。