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981.
不同蛋白水平的虾青素饲料对锦鲤体色、生长及免疫的影响 总被引:1,自引:0,他引:1
以初始体重为(5.85±0.19)g的红白锦鲤幼鱼为实验对象,研究虾青素有效添加量为130 mg/kg时,饲料蛋白水平(25.49%、30.84%、35.04%、40.68%、45.88%)对锦鲤体色、生长及免疫的影响。每组设3个平行,每个平行饲养20尾鱼,表观饱食投喂60 d后,实验结果显示:饲料蛋白水平为35.04%时,实验鱼体表红质a*值最高,与蛋白水平40.68%组间无显著差异(P>0.05),但显著高于其他实验组(P<0.05),与此同时,皮肤中类胡萝卜素含量显著升高(P<0.05),最大值出现在蛋白水平45.88%组。蛋白水平为35.04%时,实验鱼的增重率(RWG)、特殊生长率(RSG)以及蛋白质效率(RPE)最高。蛋白水平对实验鱼溶菌酶(LZM)以及实验鱼肝胰脏(CAT)、乳酸脱氢酶(LDH)无显著影响(P>0.05),蛋白水平为45.88%时,SOD活力显著降低(P< 0.05)。上述研究说明,虾青素添加量为130 mg/kg时,使锦鲤生长、着色达到最好效果的适宜饲料蛋白水平为35.04%。同时本研究的结果表明,在配合饲料中,提高饲料蛋白水平不会持续提高锦鲤对虾青素的利用效率。 相似文献
982.
983.
An indirect ELISA for detecting the IgA antibody against porcine foot-and-mouth disease virus (FMDV) type A was developed by using purified FMDV structural protein VP1 as coating antigen, mouse anti-pig IgA monoclonal antibody as second antibody and HRP-conjugated goat anti-mouse IgG as third antibody.The concentration of coating antigen was optimized as 3.50 μg/mL,the dilution and reaction time of second antibody and third antibody were optimized as 1:10 000 and 30 min, respectively.There was no cross-reactivity with anti-CSFV, PRRSV and other pathogen specific IgA antibodies.The positive detection rate of FMDV type A infectedsamples was above 90%.The coefficient variation of intra-and inter-assay was ranged from 3.16% to 9.76%.The ELISA method described in this study was proved to be specific and rapid for the detection of FMDV specific IgA antibody.It was potential to be applied for detection the level of FMDV specific IgA and evaluate the effect of mucosal immunity.Besides,it provided a new method for clinical diagnosis of foot-and-mouth disease. 相似文献
984.
Effect of dietary manipulation and vaccination of turkey breeder hens on immunoglobulin levels of yolk,yolk sac and neonate poults 下载免费PDF全文
A. Bhattacharyya S. Majumdar S. K. Bhanja A. B. Mandal B. B. Dash 《Journal of animal physiology and animal nutrition》2018,102(2):e957-e963
Two hundred turkey breeder hens and 24 viable toms of 30–35 weeks age of small white variety were distributed into two treatment groups having four replicates of 25 hens and three toms in each treatment. First four replicates were offered a turkey breeder diet (Diet A) (Nutrient requirements of poultry, 1994, National Academic Press, Washington, DC) and the rest four replicates were maintained on a higher plane of nutrition (Diet B) for 8‐week duration. After 6 weeks of experimental feeding, two replicates from each treatment groups were vaccinated with ND (R2B) vaccine. Yolk sac of embryo from birds fed Diet B had a significantly higher (p < .05) IgG, IgM level and HI titre (log 2) than those fed Diet A. HI titre values of embryonic yolk sac from the vaccinated birds fed Diet B were significantly higher (p < .05) than that of the control groups. In addition, HI titre values were significantly higher (p < .05) in the day‐old poults of the birds fed Diet B than that of those fed Diet A. There was significantly (p < .01) positive correlation between serum IgG and IgM of the breeder birds and day‐old chicks. Similarly, there was significantly (p < .05) positive correlation between yolk IgG and IgM after 1‐month experimental feeding and yolk sac IgG and IgM. Positive correlation (p < .05) also existed between yolk sac IgM and day‐old chick serum IgM. Furthermore, the HI titres of breeder birds' serum at 14 days post‐vaccination were positively correlated with their egg yolk after 10 and 15 days post‐vaccination, yolk sac and day‐old chicks. Thus, the study envisaged that a higher immunity in neonate poults from turkey breeders maintained on a higher plane of nutrition may be elicited as there was maternal transfer of antibodies from the serum of breeder birds to their offsprings through their yolk sac. 相似文献
985.
Effect of Infusing Lactoferrin Hydrolysate into Bovine Mammary Glands with Subclinical Mastitis 总被引:4,自引:0,他引:4
The therapeutic effect of administering lactoferrin hydrolysate (LFH) into the mammary glands of cows with subclinical mastitis was evaluated. Seven millilitres of a preparation of LFH (7% protein) was infused into 35 quarters of 25 cows with subclinical mastitis. The numbers of bacteria in the milk from infected quarters decreased, and bacteria disappeared by the 14th day after the administration of LFH. The mean somatic cell counts (SCC) peaked one day after administration of LFH and the counts were significantly (p<0.01) decreased on days 7, 14 and 21 compared to those before the administration of LFH. The mean lactoferrin concentration in the milk peaked on days 2 or 3 and then gradually decreased to day 14, returning to the level before the administration of LFH. It appears that administration of LFH may have a therapeutic effect when infused into the quarters of cows with subclinical mastitis. 相似文献
986.
Otto Christian Straub 《Comparative immunology, microbiology and infectious diseases》1995,18(4):253-257
Four groups of six cattle were vaccinated from two to five times at 6 month intervals with two different trivalent FMD vaccines licensed in the given year. The FMDV type A strains in the vaccines designated A5F and A5B were closely related. Three months after the last vaccination the cattle were challenged by contact with animals inoculated with the original field strain A5B. The inoculated animals developed typical FMD symptoms with vesicles in the mouth and on the feet. Those cattle which had received vaccines that did not contain strain A5B also became severely sick, even after five vaccinations. Animals vaccinated twice with type B containing vaccine were also not completely protected. A safe protection can obviously only be achieved for fairly short periods of time if vaccine and challenge strain are homologous. It is proposed to change the rules of licensing, to speed up the procedure to vaccinate in cases of outbreaks. The need for further research, especially into improving vaccines, is stressed. 相似文献
987.
988.
989.
Evaluation of Aloe vera and synbiotic as antibiotic growth promoter substitutions on performance,gut morphology,immune responses and blood constitutes of broiler chickens 下载免费PDF全文
This study was performed to investigate the effect of dietary supplementation with Aloe vera (AV) powder and synbiotic as growth promoter agents on performance, gut morphology, immune responses, hematology and serum biochemistry in broilers. A total of 240‐day‐old male broiler chicks (Ross 308) were randomly assigned to six treatments with four replicates. Birds were offered either a corn‐soybean meal basal diet (control) or the basal diet supplemented with 200 mg/kg virginiamycin (VM), 1 g/kg synbiotic (Syn), 2.5 g/kg AV (AV1), 5.0 g/kg AV (AV2) or 7.5 g/kg AV (AV3). Chickens fed any of the diets, except diet AV1, exhibited better feed conversion ratios at the 14–28 day period and higher average daily gain and duodenal villus height/crypt depth ratio at 42 days than those fed the control diet. Synbiotic supplementation caused a marked increase in the serum antibody titer against infectious bursal disease and infectious bronchitis vaccines. Feeding diet AV3 significantly increased red blood cell count and hemoglobin concentration, and decreased serum triglyceride level compared to the control group. The results suggested that dietary inclusion of 5 and 7.5 g/kg AV, similar with synbiotic supplementation, can be applied as effective alternatives to in‐feed antibiotics for broiler diets. 相似文献
990.
【目的】试验通过研究饲粮中添加过瘤胃胆碱和有机铬对围产期奶牛免疫及抗氧化功能的影响,旨在为过瘤胃胆碱和有机铬在围产期奶牛饲粮中的科学应用提供理论依据。【方法】选取40头健康、经产(平均胎次1~2)的中国荷斯坦奶牛,随机分为4组(每组10头牛):对照组(TO),基础饲粮;胆碱组(TC),基础饲粮+30 g/d过瘤胃胆碱;有机铬组(TA),基础饲粮+8 g/d蛋氨酸铬;混合组(TCA),基础饲粮+30 g/d过瘤胃胆碱+8 g/d蛋氨酸铬。试验处理从产前20 d至产后20 d,记录奶牛产后4周内日均产奶量,分别于产前第20、10天和产犊日、产后第10、20天,于晨饲前采集血样,测定血清抗氧化(谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)和超氧化物歧化酶(SOD))及免疫(白介素-1(IL-1)、白介素-6(IL-6)和肿瘤坏死因子(TNF-α))功能指标。【结果】与对照组相比,3个试验组奶牛产后4周内日均产奶量均显著提高(P<0.05);产前各组奶牛血清GSH-Px、CAT含量无显著差异(P>0.05),但试验组奶牛血清SOD含量显著降低(P<0.05);产犊日至产后第10天,胆碱组和有机铬组奶牛血清GSH-Px、CAT和SOD含量均显著高于对照组(P<0.05);产后第20天,胆碱组血清GSH-Px、CAT含量均显著低于高于对照组、有机铬组和混合组,而血清SOD含量却显著降低(P<0.05);整个试验周期内,胆碱组奶牛血清IL-1含量显著低于对照组及有机铬组和混合组(P<0.05),IL-6和TNF-α含量却显著提高(P<0.05)。【结论】综上所述,本试验条件下,饲粮中单独添加30 g/d过瘤胃胆碱或8 g/d有机铬可明显降低围产期奶牛机体氧化应激水平,提高产奶量和机体免疫力,改善奶牛健康状况,联合添加过瘤胃胆碱和有机铬与单独添加效果差异不明显。 相似文献