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1.
利用猪传染性胃肠炎病毒、猪流行性腹泻病毒、轮状病毒三联油佐剂苗和大肠杆菌K88、K99、P987多价灭活苗免疫健康蛋鸡,收集高免蛋,通过喷雾干燥法制备高免全蛋粉,并对干燥条件进行优化;结果显示:采用进风温度180℃、进料速度10mL/min、干燥速度5s、出口温度70℃喷雾的高免全蛋粉质量较好;动物试验结果表明:在早期断奶仔猪日粮中添加0.5%高免全蛋粉替代抗生素不仅可以有效降低仔猪腹泻发生率,而且能够明显提高仔猪生产性能。  相似文献   

2.
Juan J.SOLER 《中国鸟类》2012,3(4):259-273
协同进化理论的中心思想,包括巢寄生者与其宿主之间共进化关系的理论,认为时间和空间模式可揭示一些关于生态和进化动态方面的重要信息。例如,关于遗传方式和基因流在决定由寄生导致的宿主所受选择的局域模式(如拒绝卵)以及因宿主的选择压力导致的寄生者所受选择模式(如模拟卵)中所起的作用,种群的遗传结构水平为此提供了重要信息。此外,随空间变化的非生物(如气候条件)和生物(动物的表型特征)因素可能还会直接或间接影响宿主和寄生者的种群及其相互作用。通过查阅文献,我们发现大量的证据支持时间及空间上的非生物环境对寄生者和宿主卵的形态及模拟程度有重要影响。而且,有研究表明,随地理和(或)时间而变化的特殊的宿主生活史特征可能会影响新宿主最初被利用的概率以及宿主与寄生者间共进化的方向和速度。本文全面总结了以往研究中关于寄生者和宿主之间相互作用的时空模式。该时空趋势以及拒卵行为的遗传学依据和基因流的显著作用,与协同进化的动态特征相一致。然而,基因流和寄生者宿主丰富度的时空格局变化可能会导致宿主和寄生者频繁产生在形态上与直觉相反的关系(如极少或者没有模拟),这或许说明了适应的局限性。我们列举了未来需要解决的一系列科学问题,认为关于寄生者和宿主的研究在检测协同进化的地理学理论以及其它一些假说中扮演着关键角色。  相似文献   

3.
Lysozyme is one of the best characterized antimicrobial proteins in egg white. Three phenotypes of egg white lysozyme in Japanese quail, Coturnix japonica, (namely fast; slow; and the combination, FS) were observed by acid polyacrylamide gel electrophoresis. The fast phenotype showed faster mobility on Acid-PAGE than the slow phenotype. Comparison of the coding sequences for lysozyme derived from the slow and fast phenotypes revealed a nonsynonymous SNP at nucleotide position 115 from the translation initiation site, which alters AA sequence of lysozyme. This nonsynonymous SNP converted glutamine (Q) in the slow phenotype to lysine (K) in the fast phenotype at AA residue 21 of mature lysozyme (Q21K). Here, we investigated the effect of these phenotypes on muramidase activity, antibacterial activity, and hatchability. Muramidase activity toward isolated cell walls of Micrococcus lysodeikticus was in the order: fast allozyme > slow allozyme > chicken (Gallus gallus), but no significant difference was found among the 3 (P > 0.05). Antibacterial activity against live Staphylococcus aureus cells was significantly greater for the fast allozyme than the slow allozyme from 20 h after incubation (P < 0.05). For the antibacterial effects against live Escherichia coli cells, the activity of fast was significantly higher than that of slow at 16 h after incubation (P < 0.05). Hatchability was estimated for reciprocal crosses of Japanese quail with the FF (fast) and SS (slow) genotypes. Hatchability was 92.5% in FF male × SS female crosses and 87.2% in SS male × FF female crosses. A Cochran-Mantel-Haenszel test revealed a significant difference between the crosses (P < 0.05) and indicated that the female-derived slow phenotype led to improved rates of hatching. Our results suggest that the nonsynonymous SNP in Japanese quail lysozyme influences the electrophoretic migration, muramidase activity, and antibacterial activity of the protein, in addition to the hatchability of the eggs. These results demonstrate, for the first time, a significant difference in antibacterial activity and hatchability between 2 lysozyme phenotypes in Japanese quail.  相似文献   

4.
1. Single strand conformation polymorphism analysis and DNA sequencing was performed in White Leghorn hens to explore the polymorphisms present in the promoter of the prolactin gene. The effects of different genotypes on egg production and quality traits were determined, and expression of the prolactin gene in different genotypes was quantified by real time-PCR.

2. Five genotypes and four alleles at each of two Fragments of the promoter were found, of which the FG genotype in Fragment 1 and the PQ genotype in Fragment 2 were the most predominant genotypes.

3. The genotypes of Fragment 1 had significant effects (P?

4. Prolactin expression in the genotypes of Fragment 1 differed significantly and GH genotyped birds had the highest level of expression. The genotypes of Fragment 2 did not show any significant differences of expression.

5. It was concluded that the prolactin gene promoter was highly polymorphic, and had significant effects on egg quality traits in White Leghorn hens.  相似文献   


5.
The use of the biochemical and serological parameters pepsinogen, gastrin and antibodies against Cooperia, Ostertagia and Dictyocaulus in an enzyme-linked immunosorbent assay was evaluated in diagnosing gastrointestinal parasitism and lungworm disease in seven oxfendazole pulse-release bolus (OPRB)-treated and seven non-treated first-season grazing calves.

During the grazing season, no difference in growth rate was observed and the control animals showed no clinical symptoms. The Dictyocaulus antibody levels in the controls increased from turn-out, while in the treated animals the rise was postponed until August. The Cooperia antibody titres for both groups were comparable. At the end of the grazing season, the control group showed significantly higher pepsinogen and gastrin values, and Ostertagia antibody titres.

It was concluded that these parameters are a useful tool in confirming subclinical parasitism and that preventive treatment with the OPRB in a low to moderately infected environment, together with a high plane of nutrition, provided little benefit to the farmer.  相似文献   


6.
This experiment was conducted to ascertain whether the growth of Salmonella Enteritidis (SE) or Salmonella Typhimurium (ST) would be suppressed in the presence of antibodies contained in egg yolks. Specific pathogen-free chickens (102 days of age) were subcutaneously immunized with oil-adjuvanted bacterin of SE or ST, twice within a four-week interval. During 160 to 170 days of age, eggs were collected, the yolks were removed and mixed with an equal volume of physiological buffered saline, inoculated with ten colony forming units (CFU) of SE or ST, and incubated at 37 degrees C or 20 degrees C for 23 hr. The growth of organisms in each yolk solution was examined. The egg yolk derived from non-immunized hens was examined in the same manner as the controls. There was no difference in the growth titer between the antibody-positive yolk and the negative yolk. The result suggests that the antibodies in the yolk do not influence the growth of each organism, even if the hens are highly immunized.  相似文献   

7.
Tropical Animal Health and Production - The National Bovine Tuberculosis (bTB) Eradication Program for dairy cattle has been operating in Taiwan for many years and has allowed the prevalence of bTB...  相似文献   

8.
以福州、厦门地区品牌鸡蛋消费者为研究对象,运用因子分析法探究影响品牌鸡蛋购买的主要因素,再采用结构方程模型分析鸡蛋消费行为、鸡蛋属性、品牌效应之间相互关系。结果表明:鸡蛋属性和品牌效应直接影响消费者对品牌鸡蛋的购买,此外品牌效应还通过影响鸡蛋属性间接影响消费。在鸡蛋属性方面消费者主要关注安全问题,在品牌效应中消费者主要关注价格因素其次是鸡蛋品牌。因此,企业首先要提高品牌鸡蛋品质,制定合理价格,以加强消费者对品牌鸡蛋的信任程度并促进该行业的健康、可持续发展。  相似文献   

9.
10.
从浙江省10多个规模化猪场采集仔猪断奶腹泻病料,分离致病性大肠杆菌。血清学和PCR方法鉴定菌毛型主要为F4和F18。挑取1株致病性和菌毛表达较强的F4阳性菌株,接种改良M inca培养基培养,热抽提法分离菌毛并纯化菌毛蛋白。将50只蛋鸡随机分5组,分别肌注1 mL免疫原/只:A组菌毛蛋白(250μg/只),B、C和D组菌毛蛋白(250,50,10μg/只) 弗氏佐剂,E组为空白对照。21 d加强免疫。定期采血分离血清,水稀释法和饱和硫酸铵盐析法分离卵黄抗体。ELISA法检测血清和卵黄抗体效价。结果表明,F4菌毛蛋白具有良好的免疫原性:在弗氏佐剂的辅助下,二免后21 d抗体效价达最高峰,血清和卵黄抗体效价分别为4.7 lg和4.4 lg,二免后56 d血清和卵黄抗体效价仍维持在4.0 lg;另外二免后21 d,10μg/只免疫剂量与50μg/只及250μg/只相比,诱导产生的卵黄抗体效价之间差异不显著(P>0.05)。  相似文献   

11.
Three strains of commercial leghorns vaccinated at 17 to 22 weeks of age with F strain Mycoplasma gallisepticum (MG) were maintained through 117 weeks of age. The three strains differed in both mortality and percent egg production per hen housed; however, the strains did not differ in egg weight (EW), eggshell strength (ESS), or percent daily egg production. Results of this study indicate EW and ESS for F strain MG-vaccinated hens follow patterns previously reported for uninfected layers. Further, mortality may account, in part, for differences in percent egg production per hen housed between strains of F strain MG-vaccinated hens.  相似文献   

12.
The selection of sheep that are resistant to gastrointestinal parasites and have lower faecal egg counts (FECs) has been the subject of extensive research. This has led to the speculation that the Major Histocompatibility Complex (MHC) genes could be used as markers to reduce FEC. In this study, associations between variation in ovine MHC-DQA2 and various measures of FEC recorded at two times (approximately 4 and 9 months of age) were investigated in a large group of New Zealand lambs (n=4676), derived from 185 different sire-lines, of a variety of breeds and raised on 25 separate farms. Pair-sample t-tests revealed that FEC for Nematodirus spp., Strongyle spp. and total FEC differed significantly between the two assessments. A total of twenty one DQA2 alleles or DQA2-DQA2-like haplotypes were identified, with allele/haplotype presence and frequency varying significantly between farms. For example, allele *0103 was observed on all farms, ranging in frequency from 0.2 to 60.9%, while haplotype *0101-*1601 was only present on one farm, in two lambs. A number of associations between the presence/absence of these alleles and egg counts were observed, but nearly all the allelic/haplotypic associations were age and parasite specific, suggesting that immune response is both age and challenge (parasite species mix) dependent. The exception was allele *1201 which was associated with increased total FECs at both 4 and 9 months of age; with it either being, or tending toward being, significantly associated with both increased Strongyle spp. and Nematodirus spp. counts as well. However, the observed increases in egg counts were small and ranged between 5 and 32 eggs per gram. In conclusion, we believe that the MHC plays an important role in parasite resistance, but that the MHC-nematode interaction is complex and thus the development of a single gene-marker based on the "MHC effect" is unlikely.  相似文献   

13.
通过对禽流感免疫抗体进行监测与分析,全面掌握禽流感的免疫效果,提高预警能力,指导养殖场(户)制定合理的免疫程序。  相似文献   

14.
15.
通过对106株分离菌,20种药物的敏感试验,证明大肠杆菌耐药性强,对利福平99%菌株耐药,青霉素、多西环素98%菌株耐药、诺氟沙星、氧氟沙星、链霉素76%菌株耐药,敏感药物首选磷霉素和杆绝杀。0109菌株和01菌株人工致病鸡治疗试验结果和药敏结果一致。  相似文献   

16.
Using standard epidemiological methods, this study set out to quantify the risk associated with exposure to easily diagnosed factors on colony mortality and morbidity in three migratory beekeeping operations. Fifty-six percent of all colonies monitored during the 10-month period died. The relative risk (RR) that a colony would die over the short term (~50 days) was appreciably increased in colonies diagnosed with Idiopathic Brood Disease Syndrome (IBDS), a condition where brood of different ages appear molten on the bottom of cells (RR = 3.2), or with a “queen event” (e.g., evidence of queen replacement or failure; RR = 3.1). We also found that several risk factors—including the incidence of a poor brood pattern, chalkbood (CB), deformed wing virus (DWV), sacbrood virus (SBV), and exceeding the threshold of 5 Varroa mites per 100 bees—were differentially expressed in different beekeeping operations. Further, we found that a diagnosis of several factors were significantly more or less likely to be associated with a simultaneous diagnosis of another risk factor. These finding support the growing consensus that the causes of colony mortality are multiple and interrelated.  相似文献   

17.
18.
Streptococcus iniae causes invasive infections in fresh and saltwater fish and occasional zoonoses. Vaccination against S. iniae is complicated by serotypic variation determined by capsular polysaccharide. A potential target for serologically cross-protective vaccines is the M-like protein SiMA, an essential virulence factor in S. iniae that is highly conserved amongst virulent strains. The present study determined how SiMA is regulated and investigated potential as a cross-protective vaccine for fish. Electrophoretic mobility shift suggested that SiMA is regulated by the multigene regulator Mgx via a binding site in the −35 region of the simA promoter. Moreover, expression of simA and mgx was highly correlated, with the highest level of simA and mgx expression during exponential growth under iron limitation (20-fold increase in relative expression compared to growth in Todd-Hewitt broth). Based on these results, a vaccination and challenge experiment was conducted in barramundi (Lates calcarifer) to determine whether SiMA is protective against S. iniae infection and cross-protective against a different capsular serotype. The challenge resulted in 60% mortality in control fish. Formalin-killed bacterins prepared from the challenge strain resulted in 100% protection, whereas bacterins prepared from a serotypically heterologous strain resulted in significantly reduced protection, even when culture conditions were manipulated to optimise SiMA expression. Moreover, recombinant SiMA protein was not protective against the challenge strain in spite of eliciting specific antibody response in vaccinated fish. Specific antibody did not increase oxidative activity or phagocytosis by barramundi macrophages. Indeed incubating S. iniae with antisera significantly reduced phagocytosis. Lack of specific-antibody mediated opsonisation in spite of 100% protection against challenge with the homologous vaccine suggests that other immune parameters result in protection of challenged fish.  相似文献   

19.
A monoclonal antibody (mAb) against zearalenone (ZEN) was produced using ZEN-carboxymethoxylamine and -BSA conjugates. Antibody produced by one clone showing a very high binding ability was selected and found to have a higher affinity for ZEN compared to a commerciall ZEN antibody. We developed two direct competitive ELISA systems using the selected antibody (ZEN-coated and anti-ZEN antibody-coated ELISA). Quantitative ranges for the anti-ZEN antibody-coated ELISA and ZEN-coated ELISA were from 25 to 750 ppb and from 12.5 to 100 ppb, respectively. The detection limit of both methods as measured with standard solutions was 10 ppb. The intra-plate and inter-well variation of both ELISAs were less than 10%. The IC50 values for α-zearalenol, β-zearalenol, α-zearalanol, and β-zearalanol compared to ZEN were 108.1, 119.3, 114.1, and 130.3% for the ZEN-coated ELISA. These values were 100.7, 120.7, 121.6, and 151.6% for the anti-ZEN antibody-coated ELISA. According to the anti-ZEN antibody-coated ELISA, the average recovery rates of ZEN from spiked animal feed containing 150 to 600 ng/mL of ZEN ranged from 106.07 to 123.00% with 0.93 to 2.28% coefficients of variation. Our results demonstrate that the mAb developed in this study could be used to simultaneously screen for ZEN and its metabolites in feed.  相似文献   

20.
In order to study the effect of feeding graded levels of green vegetables on egg production performance and egg yolk antioxidant status, 27 female golden pheasants (GP) were randomly distributed into three groups of nine each in an experiment based on completely randomized design. The diets of the birds in groups T1, T2 and T3 contained 1.4%, 2.7% and 5.0% of green vegetables respectively. Feeding of experimental diets started on 12th February (day 1) and was continued till 30 June 2012. Average number of eggs laid and egg mass produced by the hens in group T3 was higher (p < 0.004) than those of T1 and T2. Hen day egg production was lowest (p < 0.001) in group T1. Roche yolk colour score was highest (p < 0.01) in T3 followed by T2 and was lowest in T1. Other external and internal egg quality parameters were similar among the groups. Total antioxidant capacity (TAC) of egg yolk was higher (p < 0.04) in group T3 as compared to other two groups. Egg yolk concentration of total carotenoids, β‐carotene, total sulfhydryl, protein‐bound sulfhydryl and non‐protein‐bound sulfhydryl was higher (p < 0.05), whereas concentration of malondialdehyde was lower (p < 0.024) in group T3 as compared to other two groups. Excreta concentration of corticosterone was highest (p < 0.012) in T1, followed by T2, and was lowest in T3. Egg yolk concentration of TAC and TSH was positively and that of malondialdehyde was negatively correlated with carotenoids intake. Excreta concentration of corticosterone was negatively correlated with carotenoids intake. It was concluded that incorporation of green vegetables in the diet at 5% on dry matter basis would improve egg production, egg yolk antioxidant status and the ability of the captive GP to combat stress.  相似文献   

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