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71.
在动物的精清里包含一些与动物生殖生理活动密切相关的活性蛋白和多肽.驼科动物的双峰驼、美洲驼、羊驼和澳洲考拉等哺乳动物精清中含有类似促性腺激素释放激素(GnRH)作用的活性蛋白质,诱导排卵因子(ovulation inducing factor,OIF),它能引发外周血液中促黄体素(LH)峰浓度的出现和诱发母畜排卵.OIF被认为是一种新的生物活性蛋白质或潜在的新型激素.甚至报道在牛等自发排卵动物以及人精清中也存在类似的活性蛋白.这类因子的发现对于哺乳动物生殖生理及繁殖的深入研究具有重要的意义,有助于动物克服繁殖障碍及繁殖疾病的治疗等.  相似文献   
72.
The aim of this study was to investigate the effect of P48 protein on proliferation and apoptosis of embryonic bovine lung (EBL) cells.In this study,samples which co-incubated with P48 protein and EBL cells in different concentrations at different time points were collected,the proliferation rate of the cells was detected by MTT method,and the changes in the nuclear morphology of EBL cells were observed by DAPI staining method.Meanwhile,flow cytometry was used to detect the apoptosis rate of EBL cells induced by P48 protein.Real-time quantitative PCR was used to detect the changes in mRNA level of apoptotic marker genes,and Western blotting tested the Bax and Beclin-1 protein expressions.The results showed that under the condition of 72 h and 10 μg/mL of protein concentration treatment,P48 extremely significantly inhibited EBL cells proliferation (P<0.01),while 0.1 and 0.5 μg/mL protein concentration had no inhibitory effect (P>0.05).The nuclear morphology showed no significant change after protein induction for 12 h,but wrinkled and condensed at 24 h.The nucleus was fragmented,and a sprouted apoptotic body was appeared at 48 and 72 h.Apoptosis related genes expression showed no obvious increase at 2 and 12 h at mRNA level,but gradually increased at 24,48 and 72 h,and it showed a time-dependent manner.Accordingly,the expression of apoptosis marker proteins Bax and Beclin-1 significantly increased.Flow cytometry analysis showed that the apoptosis rate of EBL cells induced by P48 protein was 48.44%.In conclusion,P48 recombinant protein of Mycoplasmas bovis inhibited the proliferation of EBL cells and promoted their apoptosis,which provided reference for revealing the pathogenic mechanism of Mycoplasmas bovis.  相似文献   
73.
Abstract

The productivity of Trifolium repens L. cv. Ladino, under irrigation in the subtropical region of Gauteng, South Africa, is unknown. The performance of T. repens was determined over five years (1981/1982 to 1985/1986), at two defoliation frequencies, four levels of nitrogen (0, 400, 800 and 1 600 kg N ha?1 ‐ total applied over five years), and either the removal or recycling of harvested material. Frequent, compared to infrequent defoliation, resulted in higher dry matter (DM) yields from the second year onwards. Dry matter yields were positively affected by the recycling of material, compared to no recycling. A mean DM yield of 191 ha?1 in the first year and 12 t ha?1 in the final year, was obtained. The highest DM yields occurred during October for all years and lowest DM yields from January to March. The first and final year showed similar peaks (late October) and troughs (March till April). Crude protein (CP) content of the herbage was influenced more by frequency of defoliation than recycling of material, where the highest CP content in any year was obtained from frequent defoliation. Nitrogen fertiliser applied up to a total of 1 600 kg N ha?1 over five years had no effect on either DM yield or crude protein content. This study has shown that T. repens could be a productive pasture for at least five years in the subtropical region of Gauteng, South Africa. Productivity and quality of T. repens were enhanced by a defoliation interval of less than five weeks and when soil high fertility was maintained by recycled plant material.  相似文献   
74.
羊痘研究概况   总被引:9,自引:2,他引:9  
羊痘病毒基因组庞大,约有150 kb,包括中间编码区和两端相同的反向末端重复序列;绵羊痘病毒和山羊痘病毒基因组彼此十分相似,约有96%的核苷酸完全相同.p32蛋白是目前世界各地分离鉴定的所有羊痘病毒株共有的且特异性很强的结构蛋白,在诊断和预防方面具有重要的应用价值.虽然羊疸从临床症状和宿主特异性上很客易做出诊断,但进一步的实验室确诊还是必要的,现已有多种检测方法和诊断试剂.控制该病最有效的方法是使用疫苗对易感动物进行免疫接种.文章从病原学、诊断和预防控制等方面对羊痘进行综述.  相似文献   
75.
The therapeutic efficacy of albendazole and netobimin in ruminants with naturally occurring fascioliasis was investigated using a recombinant-based ELISA. The variation in the IgG response against a 2.9-kDa recombinant protein (FhrAPS), termed efficacy index (EI) 1, and the egg-output changes, termed EI 2, were used to evaluate drug efficacy.The values of EI 1 ranged between 0% and 50% in sheep, and between 0% and 30% in cattle after treatment with albendazole and netobimin. Similar EI 2 values were observed in sheep receiving albendazole or netobimin, but the highest values were found in cattle treated with netobimin. The significant reduction in the IgG response to FhrAPS found in this study shows promise in terms of developing alternative methods for evaluating the efficacy of chemotherapy against Fasciola hepatica in grazing ruminants.  相似文献   
76.
补饲对湘东黑山羊血液生化指标的影响   总被引:1,自引:0,他引:1  
采用32只3~4月龄的湘东黑山羊,研究三种不同补饲水平对其血液生化指标的影响.设1个对照组与3个试验组,试验组平均补饲量依次按100 g/d、200 g/d、300 g/d.结果表明:肥育羔羊的血清尿素氮、钙、无机磷与总蛋白含量在各组间的变化范围依次是:19.77 mg/dL~20.98 mg/dL、8.28 mg/dL~10.52 mg/dL、4.14 mg/dL~4.80 mg/dL、72.53 g/L~81.33 g/L.  相似文献   
77.
本试验旨在比较不同品种类型玉米(Zea mays)不同器官和全株的生物产量,以提高玉米定向培育的选择效率。选择32种具有代表性的玉米优良品种为试验材料,根据淀粉性质、籽实外形、成熟性质和用途4种分类方法,分别对完熟期玉米的籽实、玉米芯、苞叶、叶片、叶鞘、茎秆及全株的鲜物质、风干物质、干物质以及粗蛋白质和总能产量进行比较。每个品种选择5个地块,每个地块选取10株玉米。结果表明:玉米的籽实、玉米芯、苞叶、叶片、叶鞘、茎秆和全株的鲜物质、风干物质、干物质、粗蛋白质和总能产量不同品种类型间差异均显著(P0.05)。根据淀粉性质、籽实外形和成熟性质分类不足以区别不同品种类型玉米的不同器官和全株生物产量(P0.05)。按用途分类,不同品种类型玉米不同器官和全株生物产量(玉米籽实的风干物质、干物质和总能产量除外)均差异显著(P0.05),表现为饲用玉米红粒玉米普通玉米糯玉米。对广泛种植的普通玉米和饲用玉米进行比较,设定普通玉米产量为100.0%,则饲用玉米籽实、玉米芯、苞叶、叶片、叶鞘、茎秆和全株的鲜物质产量分别为121.9%、164.2%、175.5%、149.0%、151.7%、168.8%和149.9%;风干物质产量分别为107.9%、143.7%、155.1%、139.4%、126.1%、162.0%和129.1%;干物质产量分别为107.5%、143.4%、155.0%、139.5%、125.7%、162.0%和129.21%;粗蛋白质产量分别为119.0%、142.9%、181.5%、161.6%、122.0%、137.4%和131.7%;总能产量分别为107.7%、143.8%、155.0%、139.4%、126.1%、162.0%和129.1%。玉米籽实干物质、粗蛋白质和总能产量占玉米全株的比例,普通玉米分别为47.75%、57.87%和48.49%,饲用玉米分别为39.72%、52.36%和40.48%。由此得出,普通玉米全株饲喂是"粮改饲"的最基本的策略,而饲用玉米籽实和全株生物产量都高于普通玉米,种植饲用玉米可以增加30%左右的土地利用。  相似文献   
78.
Faecal nitrogen (FN) concentration is used as a marker for habitat quality and digestive efficiency in free‐ranging herbivores. In herbivores, FN can be separated into undigested plant N (analysed as the N concentration of the neutral detergent residue) and metabolic faecal N (MFN). It has been suggested that by differential analysis of the faecal fibre‐bound N, the MFN fraction can be further split into a bacterial N and an endogenous N fraction [Hesta et al., Br. J. Nutr. 90 (2003) 1007]. We applied these methods to 96 faecal samples of 48 mammalian herbivore species from zoos. Species were grouped into coprophageous and non‐coprophageous hindgut fermenters and ruminating and non‐ruminating foregut fermenters. Diet was not controlled. The FN decreased with body mass, possibly reflecting higher proportions of concentrates in diets of smaller animals. The proportion of MFN increased with FN, indicating that higher quality food might enhance the gastrointestinal bacterial flora. The only outlier to this pattern was the lesser panda (Ailurus fulgens), confirming the low relevance of fermentative digestion in this herbivorous ‘carnivore’. No relevant differences between the four digestion types were noted. The proportion of endogenous faecal N (32–80% of FN) was always higher than that of bacterial faecal N (7–30%), which contradicts basal understanding of herbivore digestive physiology. Thus, the method of Hesta et al. (2003) does not appear applicable to herbivores. While the results do not exclude the possibility that detailed differences might occur between digestion types, they indicate a high degree of similarity between herbivores that rely on bacterial fermentation, regardless of their digestion type, with respect to metabolic faecal losses.  相似文献   
79.
水解蛋白婴儿配方奶粉的研究   总被引:1,自引:0,他引:1  
赵红霞 《乳业科学与技术》2011,34(3):112-113,117
本文介绍了婴儿对牛乳蛋白过敏的原因,并根据水解蛋白防过敏的特性生产加工了低过敏婴儿配方奶粉,通过研究分析发现其感官品质和营养成分与常规配方婴儿奶粉无明显差异。  相似文献   
80.
大豆抗原蛋白对幼龄动物致敏作用的研究进展   总被引:1,自引:0,他引:1  
大豆抗原蛋白对幼龄动物的致敏作用及不易灭活性使其成为大豆及其制品在动物养殖中有效利用的主要瓶颈。本文从主要抗原蛋白的特性、致敏机制、对幼龄动物的影响、降低抗原蛋白的方法及有待进一步探索问题等方面进行了阐述,旨在为高效利用大豆及其制品,以及进一步深入研究提供参考。  相似文献   
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