鸡蛋胆固醇含量测定方法比较研究

试验随机选取了中华绿蛋鸡产的绿壳蛋和依莎褐蛋鸡产的褐壳鸡蛋各20枚,采用邻苯二甲醛分光光度计比色法和气相色谱法,测定鸡蛋中胆固醇的含量,比较两种方法在测定鸡蛋胆固醇含量上的差异。结果表明,用邻苯二甲醛比色法测得褐壳蛋蛋黄胆固醇含量176．79mg／枚,浓度为13．35mg／g。用气相色谱法测得胆固醇含量142．74mg／枚,浓度为9．69mg／g,二种方法测定的结果差异显著（P〈0．05）。用邻苯二甲醛比色法测得绿壳蛋蛋黄胆固醇含量158．12mg／枚,浓度为10．65mg／g。用气相色谱法测得胆固醇含量128．70mg／枚,浓度为8．54mg／g,二种方法测定的结果差异显著（P〈0．05）。     

果园放养的绿壳蛋鸡蛋品质分析及安全评价

本试验对果园放养的绿壳蛋鸡蛋品质及安全评价进行了检测分析。结果表明:绿壳蛋含水量为85.16%,低于放养土鸡和笼养鸡所产蛋;蛋白、蛋黄比率达31.53%以上;所测的总氨基酸中,蛋清为12.541g/100g,蛋黄为14.256g/100g,必需氨基酸蛋清为5.361g/100g,蛋黄为5.947g/100g;蛋清、蛋黄中锌含量分别为0.51mg/100g、18.503mg/100g,硒含量分别为0.55mg/100g、3.06mg/100g,高于放养土鸡和笼养鸡所产蛋;安全指标中,除镉和氟检测有实际数值外,其它均未检出,微生物指标检测的数值也相对较低。     

不同品种禽蛋中营养元素的测定

为比较不同品种禽蛋中的营养元素（常量元素和微量元素）含量,采用电感耦合等离子体发射光谱技术测定了11种市售禽蛋中的钙、钾、钠、镁、铁、铜、锌、锰元素含量,利用钒钼黄比色法测定了11种市售禽蛋中的磷元素含量。结果显示,除磷元素外,其他8种营养元素含量均为鹌鹑蛋〉绿壳乌鸡蛋〉白壳乌鸡蛋〉其余8个品种的鸡蛋。结果提示,鹌鹑蛋、绿壳乌鸡蛋、白壳乌鸡蛋营养元素含量较高,可作为高营养价值禽蛋产品开发的重点品种。     

高效液相色谱法测定强化乳中维生素A、D和胆固醇水平

本试验建立了一种可同时测定强化乳中维生素A、D和胆固醇含量的变波长高效液相色谱法。通过紫外分光光度计选出各组分的最佳吸收波长,对液相色谱检测条件进行优化,并采用该方法对强化乳样品进行了精密度和加标回收率试验。结果显示,待测组分线性关系良好,维生素A、D和胆固醇的最低检出限分别为10IU/100g、8IU/100g、0.5mg/100g,相对标准偏差(RSD)为0.71%～1.97%,加标回收率为94.5%～97.5%。对待测组分进行检验统计学处理及t检验,结果表明,该方法灵敏、准确,重复性好,样品处理简便,其测定结果与国家标准方法一致。     

高效液相色谱法测定饲料中的那西肽

试验建立高效液相色谱法测定饲料中那西肽含量的方法。用N,N-二甲基甲酰胺提取饲料中那西肽,用高效液相色谱仪进行测定。在0.02~10.00μg/m L质量浓度范围线性关系良好;在0.50~500.00 mg/kg范围,回收率范围为80.00%~105.00%。高效液相色谱方法操作简便及结果可靠,适用于饲料中那西肽的测定。     

倒毛鸡与绿壳蛋鸡蛋品质比较

为比较倒毛鸡与绿壳蛋鸡2个优质土鸡鸡蛋品质的差异,测定了2个鸡种常规蛋水分、粗蛋白质、粗脂肪、灰分和氨基酸含量。结果表明,倒毛鸡鸡蛋的蛋白高度、哈氏单位、蛋白比例显著高于绿壳蛋鸡鸡蛋,而蛋重则显著低于绿壳蛋鸡鸡蛋;其余蛋品质指标差异不显著。倒毛鸡鸡蛋的水分含量、粗脂肪含量显著低于绿壳蛋鸡鸡蛋,粗蛋白含量显著高于绿壳蛋鸡鸡蛋;2组鸡蛋中粗灰分含量差异不显著。倒毛鸡和绿壳蛋鸡鸡蛋的氨基酸组成基本一致,均含有17种氨基酸,氨基酸总量分别是12.59 g/100 g和12.47 g/100 g,必需氨基酸占总氨基酸的比值分别为5.44 g/100 g和5.72 g/100 g。     

硒对绿壳蛋蛋品质及蛋黄生化指标的影响

膳食摄硒是一种有效的补硒方法,鸡蛋是理想供硒的功能性食品载体。本实验选取饲喂添加酵母硒(0.4mg/kg)和未添加的日粮的绿壳蛋鸡所产鸡蛋各30枚,进行蛋品质测定和蛋黄的总抗氧化能力、丙二醛含量、总胆固醇含量、甘油三酯含量和低密度脂蛋白含量的测定及各指标间的比较分析。结果显示,添加酵母硒可显著提高绿壳蛋的蛋壳厚、蛋壳重和蛋壳强度(P0.05)。对蛋黄颜色、蛋白高度、哈夫单位均有显著影响(P0.05),但对蛋重、蛋黄重、蛋黄比例、蛋形指数无显著影响(P0.05)。与未添加酵母硒的绿壳蛋相比,其总抗氧化能力显著提高(P0.05),丙二醛含量和总胆固醇含量显著降低(P0.05)。但是甘油三酯含量和低密度脂蛋白含量差异不显著(P0.05)。结果表明,在日粮中添加硒能增加绿壳蛋的蛋壳厚、蛋壳重、蛋壳强度,提高蛋的总抗氧化能力和哈夫单位,并显著降低蛋黄中总胆固醇的含量。     

不同品种绿壳鸡蛋蛋品质、胆固醇含量及蛋壳色素比较分析

为研究不同品种绿壳鸡蛋的差异,以长顺绿壳蛋鸡、赤水乌骨鸡和乌蒙乌鸡为试验材料,对其蛋品质、蛋黄胆固醇、脂肪和蛋白质含量以及蛋壳色素含量进行测定。结果显示：赤水乌骨鸡的蛋重显著高于长顺绿壳蛋鸡和乌蒙乌鸡（P<0.05）,乌蒙乌鸡的蛋黄脂肪含量显著高于其他两个品种（P<0.05）,赤水乌骨鸡的蛋黄胆固醇含量显著小于其他两个品种（P<0.05）。三种蛋壳中,胆绿素的含量均高于原卟啉含量,赤水乌骨鸡蛋壳的原卟啉含量显著小于长顺绿壳蛋鸡和乌蒙乌鸡（P<0.05）,长顺绿壳蛋鸡蛋壳的胆绿素含量显著高于其他两个品种（P<0.05）。蛋黄脂肪、胆固醇含量与蛋品质相关分析显示,3个品种的蛋黄脂肪含量与蛋黄颜色和蛋壳厚度呈极显著正相关（P<0.01）,蛋黄胆固醇含量与蛋黄重、蛋黄颜色和蛋黄比率均呈极显著正相关（P<0.01）。长顺绿壳蛋鸡蛋重与蛋黄脂肪含量、蛋黄比率与蛋黄胆固醇含量呈显著正相关（P<0.05）;赤水乌骨鸡蛋黄颜色与蛋黄胆固醇含量呈显著负相关（P<0.05）。研究表明,三种绿壳鸡蛋的蛋品质、蛋黄胆固醇、脂肪含量各有不同,赤水乌骨鸡鸡蛋的蛋...     

日粮中联合添加低聚木糖和丝兰粉对蛋鸡生产性能及脂质指标的影响北大核心

试验旨在研究日粮中联合添加低聚木糖和丝兰粉对蛋鸡生产性能及脂质指标的影响。选择96只70周龄产蛋后期绿壳蛋鸡,随机分成4组,每组4个重复,每个重复6只蛋鸡。对照组绿壳蛋鸡饲喂基础日粮,试验Ⅰ组、Ⅱ组、Ⅲ组分别在基础日粮中添加50 mg/kg低聚木糖+100 mg/kg丝兰粉、100 mg/kg低聚木糖+200 mg/kg丝兰粉、200 mg/kg低聚木糖+300 mg/kg丝兰粉。试验期6周。结果显示,试验各组蛋鸡平均产蛋数、平均日采食量、蛋重、产蛋率和料蛋比差异不显著(P>0.05)。与对照组相比,试验各组鸡蛋哈夫单位、蛋白高度和蛋壳相对重具有提高的趋势;各组蛋黄相对重、蛋形指数、蛋黄粗脂肪含量差异不显著(P>0.05)。Ⅱ组和Ⅲ组蛋黄甘油三酯和总胆固醇含量显著降低(P<0.05),Ⅱ组蛋鸡血清中低密度脂蛋白胆固醇含量比对照组降低30.71%(P<0.05)。研究表明,在产蛋后期蛋鸡日粮中联合添加低聚木糖和丝兰粉具有协同增效作用,可以改善蛋鸡生产性能和蛋品质,调节蛋鸡脂质代谢,降低鸡蛋蛋黄胆固醇含量,日粮中添加低聚木糖制剂100 mg/kg+丝兰粉200 mg/kg效果较佳。     

辣蓼黄酮中芦丁、槲皮素与槲皮苷的含量分析

前期研究中运用大孔吸附树脂法对辣蓼黄酮进行分离纯化并对其抗氧化活性进行初步试验,获得令人满意的结果。为了获得质量稳定的辣蓼黄酮,为工业化生产中的质量控制提供实验依据,通过高效液相色谱法,以芦丁、槲皮素与槲皮苷为对照品对辣蓼总黄酮进行目标成分含量测定。结果表明,运用高效液相色谱法测定辣蓼黄酮乙酸乙酯部分(FEA)中芦丁、槲皮素与槲皮苷的含量分别为281.97、160.98、83.31 mg/g,辣蓼黄酮正丁醇部分(FNB)中芦丁、槲皮素与槲皮苷的含量分别为150.33、147.51、73.82 mg/g。该方法简单、准确、灵敏,精密度、重复性好,可作为辣蓼黄酮中芦丁、槲皮素与槲皮苷含量分析的参考方法。     

Heartworm in dogs in Canada in 1989

In late November 1989, 1732 clinics and institutional veterinarians were sent a questionnaire to assess the status of Dirofilaria immitis, and 51.7% responded. Of 247,716 dogs tested, 394 had D. immitis microfilariae and 51 were amicrofilaremic for a total of 445 cases and heartworm prevalence of 0.17%. Most (408) of these dogs had no preventive medication and the prevalence among dogs tested and unprotected was 1.01%. That prevalence was considerably higher in endemic areas. Thirty-seven dogs with heartworm had preventive medication. Heartworm was most frequent in companion dogs over three years of age maintained outdoors in rural areas. About 75% of the cases had never left Canada, 26% had clinical signs and 125 were not treated.

Heartworm was reported from British Columbia, Manitoba, Ontario, Quebec, Nova Scotia and Newfoundland, but 383 cases were in Ontario. South-western Ontario was the primary focus of infection. There were 33 cases in Quebec and 24 in Manitoba, mainly found in and around Metropolitan Montreal and Winnipeg respectively.

     

Heartworm in dogs in Canada in 1987

In late November 1987, 1246 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1987, and 50% of them responded. Veterinarians reported that 165,428 dogs were blood tested for heartworm disease and 511 dogs were found with D. immitis microfilariae. Another 78 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1987 as 589 (0.35%).     

Heartworm in dogs in Canada in 1986

In late December 1986, 1224 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1986; 46% of them responded. Veterinarians reported that 150,989 dogs were blood-tested for microfilariae and 869 dogs were found with heartworm. Another 65 dogs were amicrofilaremic but diagnosed with heartworm disease and one was found with heartworm at necropsy to give the total number diagnosed in 1986 as 935 (0.62%).

Heartworm was reported from Manitoba, New Brunswick, Ontario and Quebec, but most (810) of the cases were from Ontario. South-western Ontario continued to be the primary focus of the infection in Canada. There were 103 cases reported from Quebec, mostly from and around Montreal, and 21 cases from Manitoba, from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 33% of the cases were observed with clinical signs of heartworm disease and 81% had a history of not having left Canada.

     

Heartworm in dogs in Canada in 1984

In late December 1984, 1853 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1984 and 35% of them responded. Veterinarians reported that 97,794 dogs were blood-tested to check for microfilariae and 1417 dogs (1.45% of those tested) were found with heartworm. Another 34 dogs were amicrofilaremic, but were diagnosed as having heartworm disease, to give the total number diagnosed in 1984 as 1451 (1.48%). Heartworm was reported from all provinces except Prince Edward Island and Newfoundland but most (1310) of the cases were in Ontario. In Quebec, 126 cases were reported mostly from west of Montreal.

Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 27% of the cases were observed with clinical signs of heartworm disease and 72% had a history of not having left Canada. Southwestern Ontario continued to be the primary focus of the infection.

     

Heartworm in dogs in Canada in 1983

In late December 1983, 2 800 veterinarians across Canada were sent a questionnaire in order to assess the status of heartworm disease in Canada in 1983 and 26% of them responded. Veterinarians reported that 59 504 dogs were blood-tested to check for microfilariae and 771 dogs (1.30% of those tested) were found with Dirofilaria immitis. Heartworm disease was diagnosed in all provinces except New Brunswick and Newfoundland but most (733) of the cases were in Ontario.

Heartworm disease was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 31% of the cases were observed with clinical signs of heartworm disease and 64% had a history of not having left Canada. Southwestern Ontario continues to be the focus of the infection and most of the dogs there had not left the province previously.

     

Heartworm in dogs in Canada in 1991

In late November 1991, 1883 clinics in Canada were sent a questionnaire to assess the status of Dirofilaria immitis in dogs in 1991 and there was a 60.0% response. There were 344,031 dogs tested for heart-worm (HW), 627 were found infected and the prevalence of HW infection was 0.18%. There were 417 dogs with HW in Ontario, 116 in Manitoba, 38 in Quebec, 53 in British Columbia, three in Alberta, and one in Nova Scotia. In British Columbia, all of the infected dogs but one were from the Okanagan valley which, as from 1991, is a new focus of infection in Canada. Most dogs with HW had not been on preventive medication in 1990, and the prevalence among dogs tested and unprotected was 0.59%. That prevalence was considerably higher in endemic areas. Companion dogs, over three years of age and maintained primarily outdoors in rural areas, were most frequently infected. One cat was diagnosed with D. immitis and 33 dogs had Dipetalonema reconditium.     

Heartworm in dogs in Canada in 1985

In late December 1985, 1485 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1985 and 44% of them responded. Veterinarians reported that 137,300 dogs were blood-tested to check for microfilariae and 1210 dogs were found with heartworm. Another 36 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number diagnosed in 1985 as 1247 (0.91%).

Heartworm was reported from all provinces except Prince Edward Island, Newfoundland and Saskatchewan but most (1126) of the cases were in Ontario. Southwestern Ontario continued to be the primary focus of the infection in Canada. From Quebec, 91 cases were reported mostly from and around Montreal. From Manitoba, 19 cases were reported from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 28% of the cases were observed with clinical signs of heartworm disease and 78% had a history of not having left Canada.