Decreasing profile of residual sulphaquinoxaline in eggs

1. Sulphaquinoxaline (SQ) was added to the diet of laying hens at 200 mg/kg for 7 successive days. Contents (mg/kg) of SQ in albumen and egg yolk of eggs laid after drug withdrawal were determined by high pressure liquid chromatography (HPLC). The contents in the whole egg were calculated taking into consideration the respective weights of albumen and egg yolk. 2. A time-lag in the initiation of decrease of SQ from eggs after the withdrawal of dietary SQ was observed. 3. The decreasing pattern from whole egg could be well described by the following equation with a time-lag of 1.0 d, y = 2.07e-0.5620(t-1.0), where y is the SQ content in whole egg, t is time (d) after the withdrawal of dietary SQ and a constant of 2.07 is the SQ content in whole egg laid at the withdrawal. 4. Biological half-life of SQ in the whole egg was estimated to be 1.23 d. 5. From the above equation, SQ residue of whole egg laid at 9th d after withdrawal will be below the detection limit of 0.01 mg/kg.     

菊苣提取物对蛋鸡鸡蛋胆固醇、肠道菌群和生产性能的影响

本文旨在研究菊苣提取物对蛋鸡生产性能、鸡蛋品质、肠道菌群、血清胆同醇和卵黄胆同醇的影响.300只尼克红蛋鸡随机分为5组,每组6个重复,每个重复10只,各组日粮中分别添加0、0.5%、1.0%、1.5%的菊苣提取物和1.0%的菊粉,试验进行4周.结果表明:与对照相比,不同水平的菊苣提取物或菊粉对蛋鸡产蛋率、蛋重、采食量、料蛋比、破蛋率、蛋黄重、蛋壳厚度和哈氏单位没有显著影响(P>0.05),但能显著降低鸡蛋胆固醇浓度(mg/g蛋黄)和含量(mg/蛋黄)(P<0.05),1.5%菊苣提取物添加组的动脉粥样硬化指数显著降低(P<0.05);日粮添加菊苣提取物或菊粉显著降低蛋鸡盲肠大肠杆菌数量和pH(P<0.05),1.5%菊苣提取物添加组和菊粉添加组显著增加盲肠双歧杆菌数量(P<0.05);鸡蛋胆固醇含量和盲肠大肠杆菌数量随菊苣提取物添加水平的增加线性降低(r=-0.957和r=-0.977)(P<0.05).结论:本试验在蛋鸡日粮中添加菊苣提取物或菊粉能显著降低鸡蛋胆固醇和盲肠有害菌(大肠杆菌)的数量,且不影响蛋鸡生产性能和鸡蛋品质.故在蛋鸡日粮中添加菊苣提取物或菊粉可为生产低胆同醇鸡蛋提供一条途径.     

Dynamics of amino acid and protein metabolism of laying hens after the administration of 15N-labeled wheat protein. 3. Incorporation of 15N into egg shell, egg white and egg yolk

12 colostomized laying hybrids received a ration meeting their requirement of 15N labelled wheat with a 15N excess (15N') of 14.37 atom-% over 4 days. The 15N' of the total ration amounted to 4.47 atom-%. Each hen consumed 135 mg 15N' per day. On another 4 days the same rations with non labelled wheat were fed. The 12 hens laid 56 eggs during the 8 days of the experiment. They were divided into egg shell, white and yolk of egg. In addition, the protein of the white and yolk of egg was precipitated with trichloric acetic acid (TCA) and the nitrogen in these fractions was determined. On average of the 56 eggs, the N quota in the egg shell was 5.3%, in the white of egg 49.1% and in the yolk 45.6%. The atom-% 15N' in the shells of the eggs laid on the first day of the experiment was on average 0.21, whereas only 0.03 and 0.02 atom-% 15N' resp. could be detected in the white and yolks of the eggs. On the first day after the last 15N application the atom-% 15N' in the egg shell and the white of egg was highest and amounted to 2.33 and 2.43 atom-% resp. The highest value of 1.83 atom-% 15N' in the yolk was ascertained 3 days after the last 15N intake. The mean quota of TCA-precipitable N in the white of egg is 97.6% and in the yolk 94.4% of the respective total N. The atom-% 15N' in the non-protein N-compounds was higher than in the protein fractions.     

Influence of dietary boron supplementation on some serum metabolites and egg-yolk cholesterol in laying hens

The influence of dietary boron (B) supplementation on some serum parameters and egg-yolk cholesterol was studied in laying hens. A total of 224 eighteen-week-old hens of the Hyline Brown 98 strain were assigned to 7 groups with 4 replicates of 8 hens each after 10 days of adaptation, and they were fed commercial diets supplemented with 0, 5, 10, 50, 100, 200 or 400 mg/kg (diet) B (H3BO3) for 8 weeks. Serum gamma-glutamyl transpeptidase (GGT) activity, albumin, glucose, total cholesterol, HDL- and LDL-cholesterol levels were decreased with all B levels. Except in the group receiving 5 mg/kg B supplementation, decreases were found in serum triglycerides in all groups. Serum aspartate aminotransferase (AST) activity was decreased in the groups receiving 100 mg/kg or higher levels of B. All levels of B supplementation increased lactate dehydrogenase (LDH) activity at weeks 21 and 22, while 10 mg/kg or higher levels of B increased serum globulin, urea and egg-yolk cholesterol levels. The results demonstrate that B supplementation at levels exceeding 5 mg/kg affects serum biochemical parameters and increases egg-yolk cholesterol in laying hens.     

Tissue concentrations of sulphaquinoxaline administered in the food of laying hens

1. Sulphaquinoxaline (SQ) was fed to laying hens at a dietary level of 400 mg/kg for 3 successive days. SQ contents (mg/kg) in the blood, kidney, liver, ovary, muscle (thigh) and adipose tissue collected on 1, 2, and 3 d after the start of feeding were determined by HPLC. The relationship between the SQ content in the tissues and times (d) of SQ feeding was analyzed statistically. 2. Dietary SQ was distributed throughout the whole body. 3. Contents in tissues, except the kidney, had already reached a plateau by day 1 after the start of administration whereas in the kidney it increased linearly throughout the 3 days. 4. The plateau values of SQ in the tissues were much greater than those of sulphamonomethoxine and sulphadimethoxine.     

Study of enrofloxacin and flumequine residues depletion in eggs of laying hens after oral administration

Two groups of laying hens (each n=12) were administered 10 mg/kg enrofloxacin (ENRO) (group A) or 26.6 mg/kg flumequine (FLU) (group B) by gastric catheter daily for five consecutive days. A third group (n=6) was untreated controls. Eggs were collected from day one of treatment and up to 30 days after withdrawal of the drug. Egg white and yolk from each egg were separated, and ENRO, its metabolite ciprofloxacin (CIP) and FLU residues were analysed by a high-performance liquid chromatography method with fluorescence detection. The sum of ENRO and CIP was detectable in egg white on the first day of treatment in high-level concentrations (2007.7 μg/kg) and remained steady during administration. In egg yolk, residues were detectable at day one in lower concentrations (324.4 μg/kg), increasing to the end of treatment. After treatment, these residues decreased and were detectable up to day 8 in egg white, and day 10 in yolk. FLU residues during drug administration in white were detectable in high concentrations from day one to five (6788.4-6525.9 μg/kg), and in yolk, concentrations were lower during administration (629.6-853.9 μg/kg). After drug withdrawal, FLU residues remained longer in egg white (30 days) than in yolk (26 days). For both drugs, differences of concentrations between matrices were significant.     

CDV免疫蛋鸡血清抗体与卵黄抗体的消长规律及其相关性分析

为了解产蛋鸡对犬瘟热病毒杭原的免疫反应及其血清抗体和卵黄抗体的消长规律及相关性,为制备卵黄抗体提供依据,将犬瘟热病毒接种Vero细胞和DF1细胞进行传代并测定其病毒滴度,选取细胞病变出现早,病毒滴度高的Vero细胞毒作为接种病毒抗原免疫蛋鸡。通过每10d进行蛋鸡免疫一次,四免后每30d加强免疫一次的方法进行免疫。免疫前和免疫后每10d采血分离血清和每5d收集鸡蛋提取卵黄抗体,用琼脂扩散法和间接ELISA法测定其抗体水平。结果显示,血清抗体比卵黄抗体的滴度高,两者间呈正相关性,卵黄抗体出现较血清抗体迟3～5d,卵黄抗体在三免后3～5d就已达到较高水平,此时即可开始收集鸡蛋制备卵黄抗体。     

Tissue sulfonamide concentration and correlation in turkeys

Nineteen hen turkeys (10 to 12 kg each) were used in a feeding study to determine sulfadimethoxine and sulfaquinoxaline concentrations in blood serum, liver, and skeletal muscle, as well as the respective ratios at selected withdrawal intervals. Two feeds were prepared by use of premixes to achieve 60 mg of sulfadimethoxine/kg and 100 mg of sulfaquinoxaline/kg, respectively. Each of the medicated feeds was given to 9 turkeys for 7 days. The turkeys were then fed nonmedicated feed at intervals from 24 to 56 hours and were slaughtered. One turkey was used as control. The serum/liver and serum/muscle ratios for sulfaquinoxaline were 60 to 70% higher than for sulfadimethoxine. However, the liver/muscle ratio for both sulfonamides was equivalent, approximately 3. Disposition of both sulfonamides approximated first-order pharmacokinetics. The calculated half-life of sulfadimethoxine was half that of sulfaquinoxaline, approximately 16 vs 30 hours. The coefficients of variation in the serum/tissue ratios for both sulfonamides were between 13% and 25% for serum/liver and less than 15% for serum/muscle, indicating excellent potential for using serum as a predictor of actionable concentrations of sulfonamide residues.     

犬瘟热病毒免疫蛋鸡血清抗体与卵黄抗体消长规律的研究

试验旨在了解产蛋鸡对犬瘟热病毒(canine distemper virus,CDV)抗原的免疫反应及其血清抗体和卵黄抗体的消长规律,为制备卵黄抗体提供依据。将CDV接种Vero细胞和DF1细胞进行传代并测定其病毒滴度,选取细胞病变出现早、病毒滴度高的Vero细胞毒作为接种病毒抗原免疫蛋鸡。每10 d免疫蛋鸡1次,第4次免疫后每30 d加强免疫1次。免疫前及免疫后每10 d采血分离血清,每5 d收集鸡蛋提取卵黄抗体,用琼脂扩散法和间接ELISA法测定其抗体水平。结果显示,血清抗体比卵黄抗体的滴度高,两者呈正相关性,卵黄抗体出现较血清抗体迟3~5 d,卵黄抗体在第3次免疫后3~5 d就已达到较高水平,此时即可开始收集鸡蛋制备卵黄抗体。     

苜草素对蛋鸡胆固醇代谢的影响及其基因调控机制

本试验旨在研究饲粮中添加不同水平苜草素对蛋鸡胆固醇代谢的影响,并探讨其基因表达调控机制。选取体重和产蛋率相近的26周龄尼克蛋鸡540只,随机分为5组,每组6个重复,每个重复18只。对照组饲喂基础饲粮,试验组分别在基础饲粮中添加300、600、900、1 200 mg/kg的苜草素。预试期7 d,正试期70 d。结果表明:1)试验第35天和第70天,900 mg/kg苜草素组的蛋黄胆固醇含量显著低于对照组(P0.05)。2)与对照组相比,900 mg/kg苜草素组显著升高了蛋鸡血清中高密度脂蛋白胆固醇(HDL-C)含量和高密度脂蛋白/低密度脂蛋白(HDL/LDL)(P0.05),各组蛋鸡血清中总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)含量差异均不显著(P0.05)。3)与对照组相比,600、900、1 200 mg/kg苜草素组显著降低了蛋鸡肝脏中3-羟基-3-甲基戊二酸单酰辅酶A还原酶(HMGCR)mRNA表达量(P0.05),900和1 200 mg/kg苜草素组显著升高了蛋鸡肝脏组织中胆固醇7α-羟化酶(CYP7A1)mRNA表达量(P0.05)。各组蛋鸡肝脏中固醇结合蛋白元件-2(SERBP-2)和卵巢中卵黄蛋白原受体(OVR)mRNA表达量无显著差异(P0.05)。综上,饲粮中添加苜草素降低了蛋黄胆固醇和全蛋胆固醇含量,其调控机制可能是通过抑制蛋鸡胆固醇的内源性合成和促进胆固醇向胆汁酸的转化排泄2种途径来实现。本试验推荐26~35周龄蛋鸡苜草素添加水平为900 mg/kg。     

Residues of dimetridazole in eggs after treatment of laying hens

Laying hens were dosed orally with dimetridazole (DMZ) (50 and 250 mg/kg) for 3 days or intramuscularly (50 mg/kg), also for 3 days, and the residues were determined by liquid chromatography in albumen and yolk. The sensitivity of the whole procedure was 2 ng/g. The drug was excreted preferentially into the yolk (about 57% of the total) and the elimination period lasted for 4–6 days after treatment.Abbreviations AUC area under the plasma concentration-time curve - depletion time the time needed for the DMZ concentration to fall below 0.01 g/g - elimination rate constant - Cl clearance - DMZ demetridazole     

Utilization of 15N marked urea by the laying hen. 2. Incorporation and metabolism of 15N for the synthesis of egg protein

In an N-metabolism experiment 3 colostomized laying hybrids received 2870 mg 15N-excess (15N') per animal in 6 days in the form of urea with their conventional feed rations. During the 8-day experiment the 21 eggs laid were separated into eggshell, white of egg and yolk. Weight, N-content and 15N' were determined of the individual fractions of the eggs. On an average of the 21 eggs 4.6% of the heavy nitrogen was in the egg-shells, 50% in the white of egg and 45.5% in the yolk. 2.8%, 4.5% and 5.5% (hens 1...3) of the 15N' consumed were detected in the eggs. The maximum 15N'-output in the white of egg was reached on the 6th day, whereas 15N'-output in the yolk showed a nearly linear increase in the time of the experiment. The results show that labelled nitrogen from urea is incorporated into the egg to a lower degree than after the feeding of 15N-labelled proteins and that the development of its incorporation into the white of egg and the yolk differ from that after the feeding of 15N-labelled native proteins.     

禽流感血清抗体与卵黄抗体消长规律比较研究

应用禽流感病毒二价（H5、H9）油乳剂灭活疫苗免疫160日龄非免疫蛋鸡，免疫接种后分别于第0、7、14、21、28、35 d采集相应的鸡蛋和血清，采用血凝抑制(HI)试验监测血清及卵黄中H5、H9抗体的消长规律，结果表明：H5、H9血清抗体于免疫后7 d时开始产生，14 d时到中等水平，21 d时达到最高值，一直维持到35 d之后；而H5、H9卵黄抗体与血清抗体水平相比相对滞后7 d左右；卵黄抗体与血清抗体在28 d时均达到高峰值并一直维持到35 d之后，28 d后血清和卵黄抗体达到相同水平。本研究为临床上以禽流感卵黄抗体检测替代血清抗体检测及以后禽流感高免卵黄抗体的研究提供了依据和数据。     

Decreasing half-life of dieldrin in egg yolk following a single oral administration of aldrin to laying hens

Laying hens were treated orally with a single dose of aldrin (AD) 1 mg/kg body weight. Concentrations (microgram/g) of AD or its epoxide (= dieldrin, DD) in the yolk of eggs laid for 21 days after AD treatment were determined by normal-phase high-performance liquid chromatography. The limits of determination were 0.02 microgram/g for AD and 0.03 microgram/g for DD, respectively. After AD treatment, although the low levels of AD (mean 0.02-0.03 microgram/g) were observed only during a three-day period (from 4th to 6th days), DD (mean 0.15 microgram/g) was found already on the 2nd day, indicating that the epoxidation of AD to DD in the hen's body is rapid. The highest level of DD (mean 0.40 microgram/g) was detected on the 6th day, and then DD levels decreased slowly and were detected up to the 21st day. In this decreasing phase, the half-life of DD in the yolk was estimated to be 25.6 days with a 95% confidence interval from 22.7 to 29.4 days.     

Pharmacokinetic study of clazuril (Appertex) in eggs and plasma from laying hens after single or multiple treatments, using a new HPLC method for detection

1. Anticoccidials are widely used as food additives to prevent and treat coccidiosis. They are licensed for use in a prescribed concentration and during a specific time interval with broilers and pullets, but not for laying hens. 2. This study was set up to develop a new high pressure liquid chromatography (HPLC) method to detect clazuril (CZ: (+/-)-2-chloro-alpha-(4-chlorophenyl)-4-(4,5-dihydro-3,5-dioxo-1,2,4-triazin-2(3H)-yl)-benzeneacetonitrile) in egg yolk and albumen and in plasma; to investigate both the presence of residues of CZ in eggs and its pharmacokinetic behaviour in laying hens. 3. A single oral dose (3 mg/kg BW) and multiple oral doses (3 mg/kg BW for 5 d) were investigated. The analytical method gave very good recovery (64 to 74%) in the three different matrices (yolk, albumen and plasma); precision and accuracy were within 11%. 4. After a single dose no residue was detected in eggs collected for up to 10 d, while following multiple dose treatment, CZ residues were detected until 10 d after the end of treatment. The concentration of the drug was higher in yolk than in albumen with a maximum ratio of 10 : 1. 5. Pharmacokinetics of CZ in laying hens after a single dose showed a detectable concentration of the drug up to 24 h. It reached a steady state after the third administration in multiple dosing. 6. Although further studies are necessary, these results indicate that a single oral dose of CZ could be used as an anticoccidial for laying hens due to the lack of residues in eggs.     

霉菌毒素吸附剂对产蛋鸡生产性能、蛋黄中微量元素含量、血清抗氧化和生化指标的影响

本试验旨在研究霉菌毒素吸附剂(分别命名为CZ和SF)对产蛋鸡生产性能、蛋黄中微量元素含量、血清抗氧化和生化指标的影响。选取216只38周龄健康的罗曼蛋鸡,随机分成3个组,每组6个重复,每个重复12只。对照组饲喂基础饲粮,试验组(CZ组、SF组)分别在基础饲粮中添加0.5 g/kg的CZ和SF。预试期为10 d,正试期为35 d。结果表明:1)与对照组相比,CZ组产蛋鸡试验3~5周产蛋率、日产蛋量显著提高(P0.05);饲粮中添加霉菌毒素吸附剂对产蛋鸡的平均蛋重、平均日采食量、料蛋比和死淘率均无显著影响(P0.05)。2)与对照组相比,各试验组产蛋鸡第14天和第35天蛋黄铜、锰含量均无显著差异(P0.05);CZ组第14天蛋黄锌含量显著提高(P0.05)。3)饲粮中添加霉菌毒素吸附剂对第14天和第35天产蛋鸡血清谷胱甘肽过氧化物酶活性和丙二醛含量无显著影响(P0.05)。与对照组相比,各试验组产蛋鸡第14天血清总抗氧化能力均显著提高(P0.05);SF组第35天血清总超氧化物歧化酶活性显著提高(P0.05)。4)与对照组相比,CZ组产蛋鸡血清碱性磷酸酶活性、葡萄糖含量显著降低(P0.05);SF组血清总胆固醇含量显著降低(P0.05)。由此可见,饲粮中添加霉菌毒素吸附剂CZ明显提高了产蛋鸡产蛋性能,2种吸附剂CZ和SF都增强了产蛋鸡血清抗氧化功能,改善了部分血清生化指标。     

葡萄原花青素对产蛋后期蛋鸡生产性能和抗氧化能力的影响

本试验旨在研究葡萄原花青素(grape procyanidins,GPC)对产蛋后期蛋鸡生产性能、蛋品质及血浆、肝脏和蛋黄抗氧化能力的影响。选取产蛋率、体重相近,健康状态良好的64周龄罗曼蛋鸡288只,随机分为4组,每组6个重复,每个重复12只鸡。对照组:饲喂基础饲粮;GPC50组和GPC100组:分别在基础饲粮中添加50和100 mg/kg的GPC;抗氧化剂特丁基对苯二酚(tert-butyl hydroquinone,TBHQ)组:基础饲粮+200 mg/kg TBHQ。预试期7 d,正试期56 d。结果表明:1)GPC显著抑制了产蛋后期蛋鸡产蛋率和鸡蛋哈夫单位下降(P0.05),显著增加了蛋壳厚度(P0.05)。2)GPC50组蛋鸡血浆和肝脏总超氧化物歧化酶(T-SOD)活性和总抗氧化能力(T-AOC)均显著提高(P0.05),血浆和肝脏丙二醛(MDA)含量显著降低(P0.05);TBHQ显著提高了蛋鸡血浆T-SOD活性(P0.05),显著降低了肝脏M DA含量(P0.05)。3)GPC显著提高了蛋黄T-SOD活性(P0.05),显著降低了蛋黄M DA和胆固醇含量(P0.05);TBHQ显著降低了蛋黄M DA含量(P0.05)。综上,饲粮添加GPC可改善产蛋后期蛋鸡产蛋率和哈夫单位,增加蛋壳厚度,改善机体抗氧化能力,其中以50 mg/kg GPC添加效果较好,优于200 mg/kg TBHQ。     

日粮添加甜菜碱对夏季高温蛋鸡生产性能、蛋品质及血液理化特征的影响

本研究旨在评估夏季高温时日粮添加甜菜碱对蛋鸡生产性能、蛋品质及骨骼和血液理化特性的影响.试验将480只产蛋性能一致的罗曼粉壳蛋鸡随机分为2组,每组240只,每组10个重复(24只/重复).对照组饲喂基础试验日粮,处理组蛋鸡饲喂基础试验日粮+150?mg/kg甜菜碱,试验为期8周.结果:日粮添加150?mg/kg甜菜碱对...     

Residue depletion of amoxicillin and its major metabolites in eggs

The depletion of amoxicillin (AMO) and its major metabolites, amoxicilloic acid (AMA) and amoxicillin‐diketopiperazine‐2′,5′‐dione (DIKETO) in the albumen, yolk and whole egg was studied after the oral dose of AMO (25 and 50 mg/kg body weight) to laying hens once per day for five consecutive days. Egg samples were prepared by a simple liquid–liquid extraction procedure with acetonitrile and saturated methylene chloride and analysed using liquid chromatography–tandem mass spectrometry. The results showed that AMO, AMA and DIKETO residues were mainly distributed in the yolk, where particularly high concentrations of AMO and DIKETO were found, whereas the albumen contained high concentrations of AMA. This distribution suggested that AMO and DIKETO were depleted slowly in yolk, whereas AMA was depleted slowly in albumen. The amount of AMO residue positively correlated with the dose, and the theoretical withdrawal times, which were calculated based on the residue level falling below a safe limit, were 5.21 and 7.67 days at AMO doses of 25 and 50 mg/kg, respectively. Moreover, the theoretical withdrawal times for all residues in the whole egg were 8.00 and 9.11 days at doses of 25 and 50 mg/kg, respectively. Our findings suggested that 9 days was an appropriate withdrawal time for the use of AMO in laying hens.     

叶黄素和维生素C对高温环境中蛋鸡生产性能及蛋品质的影响

研究了万寿菊叶黄素(Marigold Lutein,MAR)和维生素C(VC)对高温环境下罗曼粉壳蛋鸡生产性能和蛋品质的影响规律。将216只180日龄身体健康、体重相似的罗曼粉蛋鸡作为试验动物,随机分为6个组,每组设3个重复,每个重复12只鸡。试验1组为高温对照组,饲喂基础日粮,试验2组饲喂基础日粮+200mg/kg VC,试验3、4、5、6组在试验2组的基础上,分别添加60mg/kg、120mg/kg、180mg/kg、240mg/kg万寿菊叶黄素(分别组成复合剂Ⅰ、Ⅱ、Ⅲ、Ⅳ)。试验期56d,其中预试期14d,正式期42d。研究结果表明,在长期高温环境中,日粮中添加120mg/kg MAR+200mg/kg VC,可有效提高蛋鸡生产性能,其中采食量、产蛋率、平均蛋重分别较对照组提高26.79%(P<0.01)、13.87%(P<0.05)和4.1%(P<0.01),破壳率降低53.49%(P<0.01),死淘率为0;同时可有效改善蛋品质,与对照组比较,蛋壳厚度、哈氏单位、蛋黄相对重有提高的趋势(P>0.05);蛋黄RCF值提高2.12(P<0.01)、蛋黄红度(a*)提高90.37%(P<0.01)、蛋黄黄度(b*)提高11.36%(P<0.01)。