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1.
试验旨在研究饲料中不同蛋黄粉水平对孔雀鱼繁殖周期和产仔量的影响。选择生长状况良好且相近的成年孔雀鱼20对,随机分为四组,对照组饲喂基础饲料,试验组分别饲喂蛋黄粉含量为2%、4%、8%的混合饲料。结果显示,在试验蛋黄粉水平范围内,饲料中蛋黄粉水平越高,繁殖周期越短,对照组与试验组差异显著(P<0.05),但各试验组间差异不显著(P>0.05)。对产仔量的统计结果显示,随着饲养时间的延长和饲料中蛋黄粉水平升高,孔雀鱼产仔量增多,第三次产仔量各试验组显著高于对照组(P<0.05),但各试验组间差异不显著;总产仔量8%蛋黄粉水平最高,但与4%蛋黄粉水平差异不显著(P>0.05)。提示饲料中添加蛋黄粉可缩短孔雀鱼的繁殖周期,提高孔雀鱼产仔量,4%蛋黄粉水平为本试验中饲料最适蛋黄粉含量。  相似文献   
2.
The effect of phosphine at exposure periods of 24, 48 and 120 h on hatching and mortality of 0- to 1-day-old eggs of susceptible (TN6) and resistant (FC10) strains of Rhyzopertha dominica of field origin was investigated. The fumigant affected hatching in both the strains. In a 48-h exposure at 27 (+/- 2) degrees C, the LD99 doses for the eggs of TN6 and FC10 were 0.56 and 3.25 mg litre-1, respectively. Significant reduction in hatching was observed in treated batches with progressive increase of phosphine dose in the first 2-3 days. On subsequent days the numbers hatching were often similar to those in controls, and sometimes exceeded control hatch, especially following a 5-day exposure. A critical change in the order of susceptibility of egg and adult stages of the two strains was noticed. In 48-h exposures, eggs of the susceptible strain were more tolerant than their adults, whilst the reverse was true in the resistant strain.  相似文献   
3.
珍珠鸡是从国外引进,经人工驯养育成的一个特色品种,其蛋用性能获得了显著进展,为加快蛋产品的开发力度,增加其附加价值,对珍珠鸡蛋和海兰褐鸡蛋蛋品质及营养成分进行比较分析。试验随机抽取新鲜珍珠鸡蛋、海兰褐鸡蛋各100枚,测定其蛋外、内在品质及主要营养成分,采用Duncan新复极差法、皮尔逊相关系数进行比较分析。研究表明,在外部品质方面,海兰褐鸡蛋蛋重高于珍珠鸡蛋15.54g(35.61%),有极显著差异(P〈0.01);珍珠鸡蛋蛋壳厚度比海兰褐鸡蛋的蛋壳厚0.14mm(40%),差异极显著(P〈0.01);由于蛋重的差异,两种鸡蛋蛋黄比例、蛋白比例、蛋壳比例也均有极显著差异(P〈0.01)。在内在品质方面,两种鸡蛋蛋清pH、蛋黄高度、蛋黄系数均无明显差异;珍珠鸡蛋浓蛋白高度比海兰褐鸡蛋的低3.02mm,有极显著差异(P〈0.01);浓蛋白系数比海兰褐的高0.87,有显著差异(P〈0.05);珍珠鸡蛋蛋黄颜色比海兰褐鸡蛋的颜色大一个罗氏比色值,有显著差异(P〈0.05)。在营养成分上,以g/枚为单位,珍珠鸡蛋的主要营养成分除胆固醇高于海兰褐鸡蛋外,其他均低于海兰褐鸡蛋。以g/100g为单位,珍珠鸡蛋水分含量明显低于海兰褐鸡蛋,相差12.62(20.21%),差异极显著(P〈0.01),脂肪含量也低于海兰褐鸡蛋,差异显著(P〈0.05),相差1.34(4.4%),其它营养成分均高于海兰褐鸡蛋。珍珠鸡蛋是较海兰褐鸡蛋小、壳厚、水分含量低、营养丰富的浓缩型蛋,为珍珠鸡蛋的蛋品开发创造了条件。  相似文献   
4.
产蛋下降综合征(EDS-76)病毒DNA探针的制备及应用研究   总被引:2,自引:0,他引:2  
用纯化的产蛋下降综合征(EDS-76)病毒(H91毒株)悬液提取的核酸,经琼脂糖凝胶电泳只出现1条分子量较大、背景清晰的核酸带。用BamHI酶消化产生4个片段,大小分别为17kb、10kb、4.0kb和2.0kb。将其中的2.0kb片段克隆进pUC18DNA载体中,重组质粒DNA用digoxigenin标记作为DNA探针,在dotblot中该探针不与鹅胚尿囊液核酸抽提物、马立克氏病病毒(MDV)DNA、鸡传染性贫血病毒(CAV)DNA、SPF鸡基因组DNA等核酸反应,只与3株EDS病毒(EDS标准毒株AV-127、EDSH91毒株和从健康鹅体中分离的EDSY81毒株)DNA呈阳性反应。人工感染产蛋母鸡和雏鸡后24h即可用该探针从泄殖腔棉拭子样品中检测出EDS病毒DNA,在感染后35h仍能从部分感染鸡样品中检出。对部分探针检测阳性鸡的泄殖腔棉拭子样品用SPF鸡胚分离病毒,并用HA和HI试验检测分离病毒的特异性;在感染过程中,同时检测了血清中HI抗体的消长情况。结果表明,人工感染鸡排毒至少可以维持2个月左右,而且血清中HI抗体即使很高,也不能阻止感染鸡的排毒。  相似文献   
5.
酵母菌培养物对蛋鸡生产性能及蛋品质的影响   总被引:2,自引:0,他引:2  
270只19周龄的ISABrow母鸡随机分3组处理,每个处理5个重复,研究酵母培养物对产蛋鸡产蛋性能和蛋品质的影响。试验为期16周。酵母培养物在试验中的添加水平分别为0%、0.1%、0.2%。试验中采用的玉米-豆粕型基础日粮中粗蛋白质为16.0%,能量为2800kcal/kg。试验结果表明,饲喂添加0.1%酵母培养物组产蛋鸡的生产性能和每日产蛋量显著提高(P<0.05);各处理组之间的蛋重、饲料摄入和饲料转化率无显著差别;试验组与对照组的蛋壳质量、哈氏单位、蛋黄颜色和蛋黄中脂肪酸含量也无显著差别。  相似文献   
6.
The purpose of this experiment was to study the immunization rule of the egg yolk antibody affected by different vaccines,immunization dose and injection ways and further to discuss the optimal immunization procedures of the laying hens for the preparation of egg yolk antibody against swine Japanese encephalitis virus.180 brown laying hens without any vaccines were selected and divided into 18 groups randomly,each group of 10 hens.Groups 1,2 were the control groups,injected with the sterile saline;Groups 3 to 10 were injected with subcutaneous or intramuscular injection,and the vaccine was injected with 0.2,0.5,1.0 and 1.5 mL successively.Groups 11 to 18 were also adopted two kinds of injection,followed by the same dose of vaccine immunization.Six eggs of each experimental group were gathered before immune day and after 3,7,10,14,18,21 and 28 days,the egg yolk antibody was extracted and the titer was determined.As a result,the egg yolk antibody titers of groups 1 to 6,11 and 12 were all 0,and no significant immune response produced;The hens from 7 to 10 groups were injected with the inactivated vaccine.After 7 days,the average antibody titer reached the peak,and the duration of the antibody was 14 days.The hens from 13 to 18 groups were injected with the attenuated virus vaccine.After 14 days,the average antibody titer reached the highest value,and the duration of the antibody was 21 days.The egg yolk antibody titers were not significantly different in the two compared experiment groups with the same injection dose but with different injection ways (P>0.05).With the same injection way of each experiment group,and the difference was significant (P>0.05).Compared with some groups with the same injection and vaccine,the titer of yolk antibody was gradually increased with the increase of the immune dose,and the difference was significant (P<0.05).The results showed that,no matter intramuscular or subcutaneous injection,in order to produce a significant immune response to hens,the immune antigen dose was 1.0 mL inactivated vaccine or 0.5 mL attenuated vaccine at least.Compared with the attenuated and inactivated vaccine,inactivated vaccine stimulated the body to produce the antibody faster,but the maintenance time was shorter;The lower dose of attenuated vaccine could stimulate the body to produce antibodies,but the speed was slower,the maintenance time was longer.  相似文献   
7.
A study involving 7 white-egg and 3 brown-egg commercial layer strains was conducted at the North Carolina Piedmont Research Station to assess the effects cage population 3-bird vs. 4-bird cages and alternative molt programs on performance through 113 wk of age (791 d). The flock was divided into 3 groups; not molted (NM), maintained in continuous production; molted using feed restriction (FR), an industry-type 14-d feed withdrawal molting program initiated at 463 d of age; and molted using a nonfasted/anorexic program (NF), in which an ad libitum supply of a low protein, low energy molt feed was provided. Productivity, egg size, and egg quality were monitored at 28-d periods throughout the test providing the performance data for the white-egg and brown-egg strains with regard to these management factors. Detailed results by strain are available on the following Web site: http://www.ces.ncsu.edu/depts/poulsci/tech_info.html#layer. The performance for the 3-bird or 4-bird cage groups for either type of layer was similar, except that birds in 4-bird cages had higher feed consumption in the first production phase than did the birds in 3-bird cages. In the same time period the white-egg birds in the 3-bird cages had a greater percentage of cracked eggs and a smaller percentage of Grade A large eggs than those in 4-bird cages. No differences were observed in egg income for the 2 population sizes for either type of layer. However, due to their higher feed consumption, the white egg birds in the 4-bird cages had higher feed cost per hen for the first cycle, which was offset by the egg income component due to their increased production rate. The molted layers outperformed the nonmolted layers for both types of layers in terms of overall income over feed costs. The FR molted hens, under a program that has traditionally been used by commercial producers, outperformed NF-molted hens, indicating that further refinements are needed to make the NF program economically competitive with the FR molting program.  相似文献   
8.
9.
大银鱼卵细胞粘丝扫描电镜观察   总被引:1,自引:0,他引:1  
用扫描电镜观察了大银鱼的第Ⅲ时相,第Ⅳ时相,第Ⅴ时相卵母细胞和受精卵的卵细胞粘丝的外部形态特征和它们的粘性,并讨论了卵细胞粘丝的功能。  相似文献   
10.
固始鸡孵化期间蛋黄胆固醇、粗脂肪和锌含量分析   总被引:2,自引:0,他引:2  
对固始鸡种蛋孵化期间蛋黄中胆固醇、粗脂肪和锌含量的测定表明,胆固醇含量0~6胚龄明显升高,以后出现阶段性降低;粗脂肪含量0~6胚龄无明显变化,6胚龄以后逐渐降低;锌含量0~3胚龄和6~12胚龄明显升高,3~6胚龄和12~21胚龄降低.  相似文献   
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