人工诱发产蛋鸡脂肪肝出血综合征的研究

通过外源性注射雌激素、高能低蛋白日粮及不同油脂来源的高能日粮人工诱发蛋鸡FLHS。90只40周龄海兰灰商品蛋鸡常规笼养,随机分为9组（10×9）：基础日粮组、基础日粮注射玉米油组、基础日粮注射β-雌二醇组;高能低蛋白日粮组、高能低蛋白注射玉米油组、高能低蛋白日粮注射伊雌二醇组;牛油高能日粮组、鸡油高能目粮组、豆油高能日...     

高能量低蛋白质日粮中添加生物素对蛋鸡脂类代谢的影响

选用300日龄健康海蓝褐蛋鸡90羽,随机分为对照组、病理组、防治组3组（每组3个重复,每个重复10只）,分别饲喂正常日粮（代谢能11.30MJ/kg,粗蛋白质17.00%）、高能量低蛋白质日粮（代谢能12.81MJ/kg,粗蛋白质12.90%）和添加0.3mg/kg生物素的高能量低蛋白质日粮,试验期60d,分别于试验的1,30,60d,每组选取体质量相近的试验蛋鸡6羽,采血制备血清和采集肝脏样品及腹脂,测定血脂含量、肝脂率和腹脂率,观察其病理学变化。结果表明,与对照组相比,试验30,60d,高能量低蛋白质日粮组鸡产蛋性能、HDL-C含量显著降低,TG、TC、LDL-C、ALT、AST、肝脂率和腹脂率显著升高,肝脂肪变性明显。试验30d,与对照组比较,防治组鸡产蛋性能、HDL-C、TG、TC、LDL-C、ALT、AST、肝脂率和腹脂率差异不显著,肝脏脂肪变性不明显;与高能量低蛋白质日粮组比较,防治组鸡产蛋性能、HDL-C含量显著升高,TG、TC、LDL-C、ALT、AST、肝脂率和腹脂率显著降低。60d时,与对照组相比,防治组鸡产蛋性能、HDL-C显著降低,TG、TC、LDL-C、ALT、AST、肝脂率和腹脂率显著升高,肝脏呈现一定的脂肪变性;与高能量低蛋白质日粮组比较,防治组鸡产蛋性能、HDL-C含量显著升高,TG、TC、LDL-C、ALT、AST、肝脂率和腹脂率显著降低。结果提示,采用高能低蛋白日粮饲喂蛋鸡可以成功的建立蛋鸡脂肪肝出血征病理模型;在高能量低蛋白质日粮中添加0.3mg/kg生物素后,可显著影响蛋鸡的脂肪肝出血征蛋鸡脂类代谢,一定程度上对其具有预防作用。     

Improving effect of dietary soybean phospholipids supplement on hepatic and serum indexes relevant to fatty liver hemorrhagic syndrome in laying hens

In order to investigate the effect of dietary soybean phospholipid supplement on hepatic and serum indexes relevant to fatty liver hemorrhagic syndrome (FLHS) in layers, 135 300‐day‐old Hyline Brown layers were randomly divided into three groups (control, pathology and prevention), and each group had 45 layers with three replicates. Birds in the three groups were respectively fed the control diet, high‐energy low‐protein diet and high‐energy high‐protein diet affixed with 3% soybean phospholipid instead of maize. Results showed in the 30th day, birds’ livers in the pathology group became yellowish, enlarged in size and had hemorrhagic spots, while the prevention and control groups’ layers did not have such pathological changes. Contents of triglyceride, total cholesterol, low‐density lipoprotein – cholesterol, non‐esterified fatty acid and malondialdehyde in serum or liver homogenate in prevention and control groups were remarkably lower than those in the pathology group (P < 0.05 or P < 0.01), as with the activities of glutamic oxalacetic transaminase and glutamic‐pyruvic transaminase (P < 0.01); high‐density lipoprotein – cholesterol value was strikingly higher than that of the pathology group (P < 0.01). It is suggested dietary soybean phospholipids supplement may effectively improve hepatic and blood indexes relevant to FLHS, which provides a new point for preventing FLHS occurrence rate in laying flocks and treating human non‐alcohol fatty liver disease.     

高能低蛋白饲粮对蛋鸡肝脏apo B-100基因mRNA表达的影响

以海蓝褐蛋鸡为试验对象,探讨高能低蛋白日粮对蛋鸡肝脏载脂蛋白B-100mRNA表达关系的影响。选300日龄海蓝褐蛋鸡60只,随机分为2组,每组30只,分别饲喂正常饲粮(对照组,代谢能:2.75MJ/kg,粗蛋白:17%)、高能低蛋白饲粮(试验组,代谢能:2.99MJ/kg,粗蛋白:12.9%)。于试验0、30、60d每组选取体质量相近的试验蛋鸡6只,取肝脏样品,应用半定量逆转录聚合酶链式反应技术测定不同时期apoB-100mRNA在肝脏中的表达水平;结果显示:试验组载脂蛋白B-100mRNA表达在试验60d显著低于对照组(0.01P≤0.05)。说明高能低蛋白日粮能导致蛋鸡肝脏载脂蛋白B-100mRNA表达水平下降。     

鸡脂肪肝出血综合征发生过程中脂质代谢与血清甲状腺激素水平变化

探讨血清甲状腺激素水平与鸡脂肪肝出血综合征（FLHs）发生之间的关系。选用14日龄青脚麻鸡160只,按体质量随机分为对照组和FLHS组。对照组饲喂基础日粮,FLHs组饲喂高脂日粮（基础日粮＋10％牛油）的同时肌肉注射苯甲酸雌二醇（剂量为2．4mg／kg,每周3次,共3周）,试验期为28d。结果显示,试验期间,FLHS组鸡的体温明显降低;28和42日龄时,FLHS组鸡的平均体质量与平均采食量均显著高于对照组（P〈0．05或P〈10．01）;皮下脂肪厚度、肌间脂肪宽度、肝指数、肝脂率、皮脂率、腹脂率升高;血清TG、TC和LDL—C浓度均显著高于对照组（P〈0．05或P％0．01）,而血清HDL—C浓度均显著低于对照组（P〈0．01）;血清T3、T4和FT3水平降低,特别在试验后期降低更明显,而血清FT4水平变化不显著;同时FLHS组血清TP、ALB和PA浓度均比对照组有所提高。结果提示,FLHS可引起血清甲状腺激素水平的下降,而甲状腺激素水平的下降进一步造成脂质代谢紊乱,参与了鸡FLHS的发生。     

Effects of iron glycine chelate on laying performance,antioxidant activities,serum biochemical indices,iron concentrations and transferrin mRNA expression in laying hens

This study was conducted to evaluate the effects of iron glycine chelate (Fe‐Gly) on laying performance, antioxidant enzyme activities, serum biochemical indices and iron concentrations in laying hens. A total of 810 laying hens (Hy‐Line Variety White, 26 weeks old) were randomly assigned to six groups with five replicates of 27 layers. Hens in the control group received diet supplemented with 60 mg Fe/kg as FeSO₄, while hens in other five groups received the diet supplemented with 0, 20, 40, 60 and 80 mg Fe/kg from Fe‐Gly respectively. The results showed that dietary Fe‐Gly treatments significantly influenced (p < 0.01) the laying rate and egg weight of layers, compared with the control group. Concerning to CuZn‐superoxide dismutase (CuZn‐SOD) and total superoxide dismutase (T‐SOD) activity, Fe‐Gly groups (60, 80 mg Fe/kg) were promoted significantly (p < 0.01) compared with 0 mg Fe/kg group. The concentrations of Fe in serum, liver, kidney, spleen and ovary were increased significantly with the level dietary Fe‐Gly raised where Fe‐Gly groups (60, 80 mg Fe/kg) had observably higher Fe concentration than the control (p < 0.01) in serum, kidney and spleen. There was a trend that transferrin mRNA expression was decreased with the increase of Fe as Fe‐Gly in diets, and compared with the control, the expression was lower in the group fed diet with 60 mg/kg Fe as Fe‐Gly. In conclusion, Fe‐Gly (60 mg Fe/kg) had improved laying rate, egg weight, SOD enzyme activity, Fe absorption and protein synthesis in body and promoted iron metabolism in laying hens. Moreover, Fe‐Gly (40 mg/kg Fe) had the similar effect with control group. It revealed that FeSO₄ could be substituted by lower concentration of Fe‐Gly and Fe‐Gly may be superior to FeSO₄ for iron fortification to laying hens.     

高能低蛋白日粮致脂肪肝出血综合征鸡抗氧化能力和肝损伤的研究

选用140日龄健康海兰褐壳蛋鸡102只,随机分为对照组(饲喂日粮代谢能与粗蛋白分别为11.51MJ/kg、15.58%)和试验组(饲喂日粮代谢能与粗蛋白分别为14.47MJ/kg、12.55%),每组设3个重复,每个重复17只。于试验期第15、25、35、45、55天,每组取6只鸡测定其血清和肝脏中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)活性和丙二醛(MDA)含量,同时对肝脏作病理组织学检查。结果显示:(1)试验组蛋鸡表现肝脂蓄积,肝脂肪变性,出现典型脂肪肝出血综合征病变,证明高能低蛋白日粮可以成功复制蛋鸡脂肪脏出血综合征。(2)与对照组相比,试验组血清和肝脏匀浆中MDA含量升高,抗氧化酶SOD、GSH-Px、CAT活力最终都降低,表明机体抗氧化能力下降。结果表明,自由基在高能低蛋白日粮致脂肪肝出血综合征的发生、发展过程中起重要作用。     

有机铬对热应激蛋鸡生产性能和血液生化指标的影响

试验选用91周龄新罗曼商品蛋鸡480只,按2×2双因子试验设计随机分为5组,对照组饲喂不添加铬的玉米-豆粕型基础日粮,4个试验组饲喂在基础日粮中分别添加了以吡啶羧酸铬或酵母铬来源的0.2mg/kg或0.4mg/kg的日粮,试验30d,以研究有机铬对热应激蛋鸡生产性能和血液生化指标的影响。试验结果显示:①有机铬能在一定程度上促进热应激蛋鸡的蛋白质利用,提高热应激蛋鸡的生产性能;②铬水平对血清尿素氮有极显著的影响(P<0.01),添加0.4mg/kg铬组均极显著地低于对照组(P<0.01),说明了补铬能够抑制由高温引起的蛋白质分解过程,从而起到缓解高温应激的作用;③吡啶羧酸铬和酵母铬在作用效果上无显著的差异;从经济效益方面考虑,0.4mg/kg铬水平的酵母铬和吡啶羧酸铬经济效益较高。     

Effects of nanocalcium carbonate on egg production performance and plasma calcium of laying hens

This experiment was conducted to evaluate the effects of nanocalcium carbonate (NCC) instead of calcium carbonate (CC) on egg production, egg weight, egg mass, FCR, blood calcium and egg quality characteristics in laying hens. A total of 120 laying hens were used in a 10‐weeks trial, from week 23 to 33 of age. Laying hens were randomly assigned to six treatments with four replications, five hens each. The experimental treatments involved replacing 50% of the CC in the diet by decreasing amounts of NCC and were T1 Basal diet (BD) with 8.06% CC; T2 (6.045% of CC as a negative control); T3 (4.03% of CC replaced by 2.015% NCC); T4 (4.03% of CC replaced by 1.01% NCC); T5 (4.03% of CC replaced by 0.252% NCC) and T6 (4.03 of CC replaced with 0.126%NCC).Egg weight was unaffected by dietary treatments (p > .05). However, the egg production percentage and egg mass in T6 were less than that of other treatments (p < .05). The laying hens in the control group had the best average feed conversion ratio (p < .05). Also, the lowest concentration of calcium in hens’ blood was recorded for birds fed T6 (p < .05). The best egg shell quality (relative egg shell weight and egg shell weight/surface) was observed in T1 (p < .05).Collectively, our results demonstrated that NCC could replace CC at a lower inclusion level but extreme reduction of calcium concentration in diets (to 1.43% Ca in the T6 group) reduced production performance, egg quality characteristics, Tibia thickness and blood calcium of laying hens.     

Evaluation of feeding spray-dried bovine plasma protein on production performance of laying hens exposed to high ambient temperatures

The purpose of this study was to evaluate feeding 2 levels of spray-dried bovine plasma protein (SDP) on production performance of laying hens subjected to high ambient temperatures. Two groups of 96 Hy-Line W-98 hens (38 wk of age) were housed in each of 2 environmentally controlled chambers. At 40 wk of age, all hens were fed 3 diet treatments consisting of (1) a control diet (0% SDP); (2) the control diet supplemented with 0.75% SDP; and (3) the control diet supplemented with 1.50% SDP. Hens in each chamber (8 cages of 4 hens per cage) were ad libitum fed 1 of each diet for 5 wk. The heat stress (HS) chamber was maintained at 21°C (wk 1), 29°C (wk 2), and 35°C (wk 3 to 5). The thermoneutral chamber was maintained at 21°C during wk 1 to 5. A significant main effect of week was observed for hens maintained in the HS chamber for egg production, egg weight, egg mass, and feed consumption, which resulted in acute heat stress causing a reduction in these parameters. Hens fed the 1.50% SDP diet in the HS chamber produced greater (P < 0.05) egg mass on average than hens fed the control or 0.75% SDP diet (wk 1 to 5). During the second week of acute HS (wk 4), hens fed the control and 1.50% SDP diets had greater (P < 0.05) egg production than those fed the 0.75% SDP diet. During wk 5, hens in the HS chamber that were fed the 1.50% SDP diet produced more (P < 0.05) eggs than those fed the control diet. Therefore, based on the results of this study, acute HS negatively affected short-term production performance. In addition, feeding hens an SDP-supplemented diet may have a slight positive effect on production performance when maintained in acute HS conditions.     

Effect of hens fed dietary flaxseed with and without a fatty liver supplement on hepatic,plasma and production characteristics relevant to fatty liver haemorrhagic syndrome in laying hens

1. Two long-term experiments were conducted with Single Comb White Leghorn (SCWL) hens (line UCD-003) predisposed to fatty liver haemorrhagic syndrome (FLHS). The first investigated the effect of adding a fatty liver supplement to the diet of laying hens prior to the onset of lay, and continuing either until peak production or throughout 39 weeks into lay. The second experiment, lasting 9 months into lay, investigated the effect of adding a fatty liver supplement, with or without 100 g/kg dietary ground flaxseed, to the diet. Body weight, feed intake, plasma triglycerides (in experiment 2) and egg production were measured throughout the experiment. Liver weight, liver fat content, liver malondialdehyde (MDA) content and liver haemorrhage score and fatty acid content of liver fat (in experiment 2) were measured at the end of each experiment. 2. In experiment 1, hens given diets containing the fatty liver supplement had higher egg production and eggshell strength, but there was no difference in liver parameters including MDA content or haemorrhage score compared with controls. 3. At the end of experiment 2, hens on 100 g/kg flaxseed diets had lower body weight, liver weight, liver dry matter and fat content, and plasma triglyceride concentrations than hens given the control diets. 4. Liver haemorrhage score was positively correlated with liver weight, but not with liver fat content, plasma triglyceride concentration or liver MDA content. This suggests that reducing the liver lipid content or feeding fatty liver supplements may not be as effective in controlling FLHS as controlling the size of the liver.     

添加不同水平复合中草药对蛋鸡血清、组织以及鸡蛋抗氧化指标的影响

为研究不同水平复合中草药对蛋鸡血清、组织和鸡蛋抗氧化指标的影响,试验选用120日龄健康、体重相近的海兰褐蛋鸡300只,随机分为5组,每组6个重复,每个重复10只鸡。对照组饲喂基础日粮,试验组分别在基础日粮中添加0.4%、0.3%、0.2%、0.1%的复合中草药。试验期40d。结果表明:(1)与对照组相比,添加复合中草药制剂能够显著提高蛋鸡平均蛋重和产蛋率(P<0.05),添加0.1%、0.3%和0.4%复合中草药组平均蛋重分别提高6.4%、4.4%和6.0%(P<0.05);添加0.3%复合中草药组产蛋率显著提高22.2%(P<0.05);(2)添加0.3%和0.4%复合中草药组超氧化物歧化酶(SOD)活性分别提高5.5%和5.9%(P<0.05);(3)添加0.4%复合中草药组肝脏SOD含量和总抗氧化能力分别提高56.0%和37.0%(P<0.05);(4)添加0.2%、0.3%和0.4%复合中草药组鸡蛋SOD酶活性分别提高8.3%、18.0%和25.2%(P<0.05)。综上所述,在本试验条件下,饲粮中添加复合中草药能够改善蛋鸡生产性能和蛋鸡血清、组织和鸡蛋抗氧化能力,以添加0.4%的复合中草药制剂效果较好。     

Coordinated gene expression in adipose tissue and liver differs between cows with high or low NEFA concentrations in early lactation

Dairy cows with high and low plasma non-esterified fatty acid (NEFA) concentrations in early lactation were compared for plasma parameters and mRNA expression of genes in liver and subcutaneous adipose tissue. The study involved 16 multiparous dairy cows with a plasma NEFA concentration of >500 μmol/l [n = 8, high NEFA (HNEFA)] and <140 μmol/l [n = 8, low NEFA (LNEFA)] in the first week post-partum (pp). Blood samples, adipose and liver tissues were collected on day 1 (+1d) and at week 3 pp (+3wk). Blood plasma was assayed for concentrations of metabolites and hormones. Subcutaneous adipose and liver tissues were analysed for mRNA abundance by real-time qRT-PCR encoding parameters related to lipid metabolism. Results showed that mean daily milk yield and milk fat quantity were higher in HNEFA than in LNEFA cows (p < 0.01), and the NEB was more negative in HNEFA than in LNEFA in +3wk too (p < 0.05). HNEFA cows had slightly lower (p < 0.1) insulin concentrations than LNEFA cows across the study period, and the body condition score decreased more from +1d to +3wk in HNEFA than in LNEFA (p = 0.09). The mRNA abundance of genes in the liver related to fatty acid oxidation (carnitine palmitoyltransferase 2 and very long chain acyl-coenzyme A dehydrogenase) and ketogenesis (3-hydroxy-3-methylglutaryl-coenzyme A synthase 2) were lower in HNEFA than in LNEFA cows. No differences between the two groups were observed for mRNA expression of genes in adipose tissue. The number of calculated significant correlation coefficients (moderately strong) between parameters in the liver and in adipose tissue was nearly similar on +1d, and higher for HNEFA compared with LNEFA cows in +3wk. In conclusion, dairy cows with high compared with low plasma NEFA concentrations in early lactation show differentially synchronized mRNA expression of genes in adipose tissue and liver in +3wk that suggests a different orchestrated homeorhetic regulation of lipid metabolism.     

Effects of phenyllactic acid on production performance,egg quality parameters,and blood characteristics in laying hens

Organic acids have been widely used as feed additives to replace antibiotics in livestock feeds. Data on the use of phenyllactic acid (PLA) are lacking. The effects of PLA on production performance, egg quality parameters, and blood characteristics in laying hens were studied in a 35-d experiment. A total of 240 ISA Brown 36-wk-old layers were divided into the following 4 treatments: 1) control (basal diet), 2) control + 0.1% PLA, 3) control + 0.2% PLA, and 4) control + 0.3% PLA. Although supplementing the diet with PLA did not affect ADFI and FE, it linearly improved egg production rate, eggshell breaking strength, and Haugh units. Egg weight, eggshell thickness, and egg yolk color were not significantly altered by supplementing the diet with PLA. White blood cell, red blood cell, total protein, and albumin concentrations were higher in the control + 0.1% PLA and control treatment groups (P < 0.05), whereas the groups fed the control + 0.2% PLA and control + 0.3% PLA diets had greater (P < 0.05) lymphocyte concentrations. In conclusion, PLA may exert some positive effects to the immune system and egg production over the short term. It may be beneficial to supplement the diets of laying hens with PLA in the absence of antibiotics. This experiment involved a small experimental sample and a short time, so the beneficial effects of PLA should be studied further in commercial farms over the long term.     

低磷日粮中添加植酸酶对蛋鸡肠道形态结构的影响

试验旨在研究在低磷的玉米-豆粕型日粮中添加植酸酶对蛋鸡肠道形态结构的影响。选用18周龄体重、产蛋周龄相近的伊莎褐蛋鸡840羽,随机分成7组:正、负对照组及在负对照组基础上分别添加300、1000和10000U/kg的包衣状植酸酶、300U/kg的粉状及300U/kg的微丸状植酸酶(试验Ⅲ、Ⅳ、Ⅴ、Ⅵ和Ⅶ组)。结果表明:与负对照组相比,Ⅳ组的空肠绒毛高度得到了显著提高(P<0.05),Ⅲ、Ⅴ、Ⅵ和Ⅶ组与之相比无显著差异(P>0.05),但分别提高了16.49%、21.80%、15.73%以及17.29%;隐窝深度、绒毛高度/隐窝深度、黏膜厚度与之相比差异不显著(P>0.05)。各试验组间以及试验组与正对照组之间亦无显著差异(P>0.05)。因此,在低磷日粮中添加植酸酶对蛋鸡肠道结构具有一定的改善作用。     

Effects of vitamin E supplementation on performance,serum biochemical parameters and fatty acid composition of egg yolk in laying hens fed a diet containing ageing corn

This study investigated whether dietary vitamin E (VE) supplementation could alleviate any detrimental effects of ageing corn in the diet for laying hens on egg performance, egg quality, serum biochemical parameters, cholesterol content and the fatty acid (FA) profile of egg yolks. The experiment consisted of a 2 × 3 factorial design with two corn types (normal corn and ageing corn) and three concentrations of VE (0, 20 and 100 IU/kg). A total of 216 Lohmann laying hens (50‐week‐old) were randomly allocated into six treatment diets for 12 week. Each treatment had six replicates with six hens. The results showed that ageing corn significantly reduced average daily feed intake (ADFI; p < 0.01) and egg weight (p < 0.05). Dietary VE supplementation had no significant influences on egg production performance (p > 0.05). Egg yolk colour was decreased in ageing corn diets (p < 0.01), while 20 and 100 IU/kg VE significantly improved vitelline membrane strength (p < 0.01) compared with feeding of 0 IU/kg VE. Ageing corn also significantly decreased the content of cholesterol including total cholesterol (TC; p < 0.05), low density lipoprotein cholesterol (LDL‐C; p < 0.01) and very low density lipoprotein cholesterol (VLDL‐C; p < 0.05) in the serum. Feeding 100 IU/kg VE significantly increased the content of LDL‐C (p < 0.01) and VLDL‐C (p < 0.05) in the serum. Furthermore, the content of the oleic acid, docosahexaenoic acid and total monounsaturated fatty acid (MUFA) was lower (p < 0.05) and stearic acid and total saturated fatty acid (SFA) was higher (p < 0.05) in egg yolks in ageing corn diets. Ageing corn resulted in reduced feed intake, egg weights and yolk colour, but the effects of VE supplementation were independent of those of age of corn and were unable to counteract the negative effects of feeding ageing corn.     

肉鸡脂肪肝综合征血液流变学和生化指标变化的研究

用高脂肪日粮饲喂45日龄三黄肉鸡，建立脂肪肝综合征（fatty liver syndrome, FLS）病理模型，系统观察了FLS鸡血液流变学和生化指标的变化规律。与正常对照鸡比较，FLS鸡全血黏度、血浆黏度、全血高切还原黏度、全血低切还原黏度、全血高切相对指数、全血低切相对指数显著升高（P〈0．01），ESR血沉、血沉方程k值降低（P〈0．01）；血清甘油三酯含量、总胆固醇含量、低密度脂蛋白胆固醇含量、丙氨酸氨基转移酶活性、天门冬氨酸氨基转移酶活性以及肝脂肪含量和肝指数明显升高（P〈0．01）。