二氢杨梅素对罗非鱼生长、免疫和抗氧化机能的影响

<正>二氢杨梅素(dihydromyricetin,DMY)——3,5,7,3',4',5'-六羟基2,3双氢黄酮,又名双氢杨梅树皮素,是从藤茶中提取的一种天然植物添加剂。DMY具有抗氧化、清除自由基、抑菌杀菌、保肝护肝、抗炎、镇痛,增强免疫力和促进生长等功效。     

维生素的免疫功能

维生素是维持动物良好的营养状态和生产性能所必需的营养物质,是许多酶的辅酶或辅基,间接参与免疫细胞增殖分化和DNA、RNA、抗体的合成。维生素缺乏、中毒及不平衡需要动物对营养畸形作出代谢性补偿,从而导致某些代谢性疾病的发生、免疫功能下降,并最终降低动物的整体生产性能和健康状况。1维生素A和β-胡萝卜素1.1维生素A(VA)VA是高等动物生长、健康和生命所必需的(McDowell,1989)。VA有以下代谢功能:视觉、上皮的维护、繁殖、骨骼形成、转录的调控、胚胎发育、造血和免疫。大量试验表明,VA是维持机体正常免疫功能的重要营养物质,…     

酵母多糖对免疫抑制小鼠的免疫调节作用

为研究酵母多糖(YPS)对免疫抑制小鼠的免疫调节作用,将180只小鼠随机分成5组,分别为空白对照组、CY模型组、试验Ⅰ组(低剂量组)、试验Ⅱ组(中剂量组)、试验Ⅲ组(高剂量组),每组3个重复,每个重复12只.除空白对照组外,其余各组小鼠均按40 mg/(kg·w)连续3d腹腔注射环磷酰胺制备免疫力低下小鼠模型,造模后,试验Ⅰ、Ⅱ、Ⅲ组给小鼠分别每天灌服0.2、0.5、1 mg/mL的YPS 0.1 mL/10g体重,空白对照组和CY模型组灌服等量生理盐水.30 d后,检测各组小鼠免疫学指标.结果表明,试验Ⅰ组可显著提高免疫抑制小鼠的脾淋巴细胞增殖能力、迟发型变态反应、巨噬细胞吞噬率、巨噬细胞吞噬指数、NK细胞活性、血清中IL-4和IFN-γ的水平.试验Ⅱ、Ⅲ组显著提高免疫器官指数、抗体生成细胞溶血空斑数和血清溶血素抗体积数,极显著地提高免疫抑制小鼠的脾淋巴细胞增殖能力、迟发性变态反应、巨噬细胞吞噬率、巨噬细胞吞噬指数、NK细胞活性、血清中IL-4和IFN-γ的水平.说明YPS能不同程度的提高免疫抑制小鼠的免特异性和非特异性免疫功能.     

L-肉碱与辅酶Q10添加对腹水症敏感肉鸡生产性能和部分免疫功能的影响

研究了日粮L-肉碱与辅酶Q10(辅酶Q)添加对腹水症敏感肉鸡生产性能和免疫功能的影响。L-肉碱添加水平分别为0、75、100 mg/kg,辅酶Q添加水平分别为0、40 mg/kg。480只1日龄艾维茵公肉鸡随机分为12组,每组设5个重复,每个重复8只鸡。试验持续6周。试验结果表明:单独添加L-肉碱或辅酶Q对肉鸡生产性能没有显著影响,可显著提高肉鸡0~3周的心脏指数(P<0.05),而对免疫器官的发育没有影响。日粮中单独添加L-肉碱能够显著降低红细胞压积(PCV)(P<0.05),而单独添加辅酶Q却没有显著效果。分别单独添加L-肉碱、辅酶Q以及二者同时添加时均可显著降低肉鸡的腹水心脏指数(AHI)以及腹水症死亡率(P<0.05)。单独添加L-肉碱显著提高肉鸡血清中IgG的含量(P<0.05),而单独添加辅酶Q以及二者同时添加时IgG含量没有显著变化;L-肉碱与辅酶Q共同添加时显著提高血清溶菌酶活性(P<0.05)。单独添加辅酶Q以及二者同时添加时,刀豆素A(ConA)刺激丝裂原淋巴细胞增殖反应显著降低(P<0.05)。本试验结果表明肉鸡腹水症敏感性的降低,可能与日粮中L-肉碱和辅酶Q的共同添加改善了机体部分免疫功能作用有关。     

Histology and Ultrastructure of the Gut of the Tilapia (Tilapia spp.), a Hybrid Teleost

The morphology of the intestine has been studied in a species of warm water fish, Tilapia spp., a hybrid teleost of notable economic importance. Light and electron microscope results show that the intestine is a relatively undifferentiated muscular tube lined with a simple columnar epithelium interspersed with goblet cells. The proximal region has a greater surface area, manifested by elongated mucosal ridges. The enterocytes are covered apically with uniform microvilli and exhibit the typical ultrastructural features of pinocytosis, namely extensive invaginations of the luminal plasma membrane and massive accumulation of vesicles in the apical cytoplasm. The distal intestine mucosa is thinner and less elaborately folded and consists of columnar cells with shorter and sparser microvilli. Their supranuclear cytoplasm contains abundant clear vacuoles. Numerous endocrine cells can also be seen. Regional cellular ultrastructural features are correlated with digestive functions.     

Temperature Acclimation in Tilapia Sparrmanii: Some Effects of Thiourea

Mastomys natalensis, Aethomys chrysophilus and Saccostomus campestris are three common and widespread rodent species in the Kruger National Park. Chromosomal and protein electrophoretic investigations reveal that these species are in fact complexes of morphologically similar, though genetically distinct, species. Their respective distributions in the Kruger National Park are reported and species diagnostic characters (diploid chromosome number, genitalia, spermatozoa and electromorphs) are presented for the practical identification of the cryptic species. The value of a genetical approach to resolving cryptic species is emphasized with respect to ecological studies.     

Efficacy of Spray Administration of Formalin-Killed Streptococcus agalactiae in Hybrid Red Tilapia

Abstract

An initial evaluation of spray vaccination was carried out with 60 hybrid Red Tilapia Oreochromis spp., divided into three groups that consisted of 10 fish per group with duplicates. The formalin-killed cells (FKCs) of Streptococcus agalactiae were administered once to group 1 by spray and once daily for five consecutive days to group 2. Group 3 remained as the untreated control group and was sprayed with normal saline. A booster was given twice to all the groups, once at the second week and again at the fourth week after the first vaccination. After this initial evaluation, a challenge study was conducted with 40 tilapia divided into two groups that consisted of 10 fish per group with duplicates. Group 1 was vaccinated with FKCs of S. agalactiae by a single spray administration while group 2 remained as the untreated control group. A booster was given twice using the same protocol as in the initial evaluation. After 6 weeks, fish from one of the duplicate tanks from each of groups 1 and 2 were challenged with pathogenic S. agalactiae by intraperitoneal (IP) injection, while fish in another tank were challenged through immersion. Based on the observations, serum immunoglobulin M (IgM) levels were significantly higher (P < 0.05) in the challenged fish than in the either the preexposed fish or the control group 1 week after the initial exposure. However, no significant differences (P > 0.05) were noted between challenged groups 1 and 2. In addition, no significant differences (P > 0.05) were observed between the frequencies of exposure. The mucus IgM level, however, remained high after each booster until the end of the 8-week study period. Meanwhile, serum IgM levels decreased after the challenge. A higher percentage of survival was noted for fish challenged through immersion (80%) compared with IP injection (70%). These results suggested that single spray exposure was able to induce IgM, which gave moderate to high protection during the challenge study.

Received October 9, 2012; accepted February 22, 2013     

谷氨酰胺对肉仔鸡免疫器官发育及免疫功能的影响

240只1日龄艾维菌肉仔鸡,随机分为4组，Ⅰ组为对照组，Ⅱ～Ⅳ组为试验组，各组分别在基础日粮中添加0、0.1％、0．2％及0、4％的谷氨酰胺（Gln），研究Gln对肉鸡免疫器官发育及免疫功能的影响。结果表明：饲料中添加不同剂量的Gln均可显著提高14日龄肉鸡的胸腺和脾脏指数（P〈0.05），且有明显量效关系；21、28日龄时上述指标仍高于对照组。但仅Ⅱ、Ⅲ组与对照组差异显著；Gln对法氏囊的发育无明显效果；添加Gln可显著提高肉仔鸡外周血淋巴细胞的转化率及T淋巴细胞数量，增强肉仔鸡对新城疫疫苗的免疫应答（P〈0.05），对提高肉仔鸡血清IgG水平亦有一定作用．其中14日龄时以添加0.4％的Gln作用效果最好，而28日龄时则以添加0.1％的Gln效果最好，Gln对红细胞免疫功能没有明显作用。     

Isolation and Pathogenicity of Streptococcus iniae in Cultured Red Hybrid Tilapia in Malaysia

Abstract

This study describes the isolation and pathogenicity of Streptococcus iniae in cultured red hybrid tilapia (Nile Tilapia Oreochromis niloticus × Mozambique Tilapia O. mossambicus) in Malaysia. The isolated gram-positive S. iniae appeared punctiform, transparently white, catalase and oxidase negative and produced complete β-hemolysis on blood agar, while a PCR assay resulted in the amplification of the 16 S rRNA gene and lactate oxidase encoded genes. The isolate was sensitive to tetracycline, vancomycin, and bacitracin but was resistant to streptomycin, ampicillin, penicillin, and erythromycin. Pathogenicity trials conducted in local red hybrid tilapia (mean ± SE = 20.00 ± 0.45 g) showed 90.0, 96.7, and 100.0% mortality within 14 d postinfection following intraperitoneal exposure to 10⁴, 10⁶, and 10⁸ CFU/mL of the pathogen, respectively. The clinical signs included erratic swimming, lethargy, and inappetance at 6 h postinfection, while mortality was recorded at less than 24 h postinfection in all infected groups. The LD_{50-336 h} of S. iniae against the red hybrid tilapia was 10² CFU/mL. The post mortem examinations revealed congested livers, kidneys, and spleens of the infected fish. This is the first report of S. iniae experimental infection in cultured red hybrid tilapia in Malaysia.

Received January 20, 2017; accepted July 16, 2017 Published online October 11, 2017     

肉鸡免疫系统功能的营养调控研究进展

构成机体免疫系统的基本物质蛋白质和氨基酸等,以及参与免疫应答的微量元素和维生素等营养物质都对肉鸡免疫系统功能的发挥起着重要作用。本文综述了近年来国内外有关饲粮营养物质水平和饲料添加剂对肉鸡免疫功能的营养调控作用研究,旨在为肉鸡的健康养殖提供理论依据。     

中药煎剂提高肉仔鸡免疫功能的研究

为了研究补益类中草药对肉仔鸡免疫功能的影响,通过检测新城疫(ND)-HI抗体滴度和外周血液T淋巴细胞百分率,从体液免疫和细胞免疫2个方面研究中草药的免疫调节功能。结果表明:肉仔鸡饲喂中药煎剂后,ND-HI抗体滴度和外周血液T淋巴细胞百分率较空白对照组均有显著提高。说明中药煎剂具有提肉仔鸡体液免疫和细胞免疫的双重功能。     

有机铬对应激牛免疫功能的影响

在牛的生产实践中,周期性应激是经常发生的现象。肉犊牛的断奶、上市、运输、混群、适应围栏肥育及奶牛的分娩、泌乳均使机体处于巨大的生理、心理和代谢应激下,表现为一个时期内采食量减少［１,２］,对铬的需要量增加［３］,机体免疫系统紊乱,犊牛的呼吸系统综合征...     

甘氨酰谷氨酰胺对粤黄鸡免疫功能的影响

谷氨酰胺（Gln）是动物血液及其它组织中含量最丰富的一种氨基酸，在维持免疫细胞的正常功能、调节机体免疫机能方面起着重要的作用。Gln是淋巴细胞的主要能量来源，在淋巴细胞、巨噬细胞、中性粒细胞的增殖和活化以及巨噬细胞、中性粒细胞的过氧化物的产生中均具有重要的作用。但是，Gln的溶解度较低，在水中很不稳定，易分解。上述特性限制了Gln的应用。     

泰山赤灵芝提取物对雏鸡免疫系统影响的研究

采用水提法从泰山赤灵芝中制备提取物 ,提取率为 3 .48% ,采用蒽酮法测定泰山赤灵芝提取物 ( Taishan Ganoderma lucidum Ex-tract,TGL E)中灵芝多糖含量为 2 0 %。本试验研究了 TGL E对京白 系雏鸡免疫器官发育、组织学变化、血液中白细胞总量、白细胞组成以及 T、B淋巴细胞组成的影响。结果表明 ,TGL E能够促进雏鸡免疫器官的生长发育及组织分化 ,血液中白细胞总量增加显著 ,白细胞组成比例发生明显变化 ,血液中 T淋巴细胞比例显著增加 ,同时 B淋巴细胞比例显著降低。     

天蚕素对肉仔鸡生产性能及免疫功能的影响

本试验在基础日粮中添加天蚕素、免疫多糖、圆葱寡糖和维吉尼亚霉素,对肉仔鸡的生产性能、免疫器官及功能的影响进行了研究。结果表明,添加天蚕素的试验组与添加免疫多糖、圆葱寡糖和维吉尼亚霉素的对照组在肉仔鸡体重和饲料报酬方面无显著性差异(P>0.05)。28d时天蚕素试验组的脾脏重和脾脏指数、胸腺重和胸腺指数显著高于免疫多糖组和维吉尼亚霉素组(P<0.05),表明天蚕素对肉仔鸡免疫器官的影响与圆葱寡糖一致,高于免疫多糖和维吉尼亚霉素。28 d时添加天蚕素组、免疫多糖组和圆葱寡糖组的ND抗体效价显著高于添加维吉尼亚霉素组(P<0.05);添加天蚕素与圆葱寡糖组的白细胞数显著高于免疫多糖组(P<0.05),极显著高于添加维吉尼亚霉素组(P<0.01)。表明天蚕素、圆葱寡糖和免疫多糖具有促进免疫细胞生长,增强肉仔鸡免疫功能的作用。     

A型流感病毒感染免疫应答中细胞因子的作用

A型流感病毒是引起人和禽类呼吸道疾病的重要病原体。病毒在宿主的上皮细胞和中性粒细胞中复制并刺激机体产生具有各种生物活性的细胞因子。细胞因子作为天然免疫的一部分,具有抗病毒和辅助Th1型免疫应答的作用,同时细胞因子也影响适应性免疫应答和疾病的表现型。流感病毒感染导致趋化性细胞因子、促炎性细胞因子、肿瘤坏死因子α以及抗病毒细胞因子的产生。论文综述了细胞因子在A型流感病毒感染的免疫应答中的可能作用,为更好地阐明病毒感染的发病机理奠定基础。     

红景天对高原缺氧条件下肉鸡免疫功能的影响

本试验通过在日粮中添加不同比例的红景天,研究红景天对低氧应激条件下肉鸡免疫功能的影响。试验选用270只1日龄雄性AA肉仔鸡,随机分为3组,每组6个重复。3组日粮分别添加0、0.5%、1.5%红景天粉。在试验的第21和42天每个重复选取2只鸡心脏采血,屠宰并分离脾脏、胸腺和法氏囊,测定免疫器官指数、淋巴细胞转化率、血清免疫球蛋白IgA和IgG浓度。结果显示,适量添加红景天可以促进低氧应激条件下肉鸡免疫器官发育,提高淋巴细胞转化率和血清中IgA和IgG浓度。表明饲料中添加一定比例红景天能够提高低氧应激条件下肉鸡的免疫力。     

内源性NO在雏鸡球虫感染中的作用

以腹腔注射途径给予感染柔嫩艾美耳球虫 (E.tenella)雏鸡细菌脂多糖 (L PS)和地塞米松 (Dex) ,用铜离子活化镉还原法检测血清 NO- 2 水平 ,并通过测定 NBT阳性细胞百分率、雏鸡增重、免疫器官的脏器系数、OPG值以及盲肠病变记分等指标 ,探讨了 NO在雏鸡感染球虫过程中的作用。试验结果表明 ,与空白对照组相比 ,给予 L PS可使 NBT阳性细胞百分率明显升高 (P<0 .0 1) ,并使盲肠病变及球虫感染引起的增重下降有所减轻 ,这提示 L PS对雏鸡具一定的保护作用 ;而给予 Dex不仅降低了感染雏鸡血清 NO- 2 的水平、NBT阳性细胞百分率、增重和胸腺的脏器系数 ,还增加了 OPG值和盲肠病变记分 ,说明在雏鸡感染球虫过程中 ,Dex会减少 NO的生成 ,并使雏鸡抗球虫免疫力下降。