袋装秸秆氨化饲料的调制与饲喂

1机理 秸秆的氨化处理技术就是在秸秆中加入一定比例的氨化物进行碱化处理,常用的氨化物是尿素。秸秆中的纤维素和半纤维素与木质素之间的化学键在碱性物质中不稳定,用尿素处理的秸秆,可以使部分纤维素及半纤维素分解,从而改变细胞壁的结构。尿素分解释放的氨与秸秆中的有机物发生化学反应,使秸秆中的半纤维素和部分木质素溶解。     

氨化饲料的制作,饲用技术及其效果

氨化饲料是将氨化剂,如氨水、尿素等,按一定比例加入秸秆饲料中,充分拌匀,在密封的条件下,经过一定时间的氨化处理,以提高秸秆饲料的营养价值和适口性。秸秆饲料的主要营养成分是粗纤维,粗纤维中含有纤维素、半纤维素和木质素。其中纤维素和半纤维素可以被牛羊等反刍家畜消化利用,还有部分纤维素与木质素紧密结合,难于被消化利用。氨化可以破坏纤维素与木质素表面之间的结合,并使少量木质素溶解,纤维素和半纤维素表面保护层结构改变,细胞壁膨胀,纤维软化,从而提高粗纤维的消化率。由于秸秆对氨有吸附作用,所以氨化还可以提高秸秆饲料中游离氨的含量,增加秸秆饲料中的粗蛋白质。 一、氨化饲料的制作 1.氨化原料     

快速加压氨化对稻秸超微组织结构的影响

用扫描电镜观察加压氨化后水稻秸秆在瘤胃不同时间段降解的超微形态变化,探明快速加压氨化条件下的氨化效果及不同氨化压强对秸秆的氨化作用。水稻秸秆经快速加压氨化(氨化压强0.1、0.2、0.3 MPa)后,取稻草的茎连同未氨化的对照样植入瘘管羊瘤胃内,分别消化6、12、24、48、72 h,取出后立即制作电镜样品。结果表明:快速加压氨化明显加快水稻秸秆薄壁组织、厚壁组织(主要是次生细胞壁)和维管束组织的韧皮部在瘤胃中的降解。处理组比对照组薄壁组织、大维管组织的韧皮部瘤胃降解时间分别缩短48、24 h以上;小维管组织瘤胃内降解未见明显变化;处理组厚壁组织的次生壁从48 h开始到72 h仍在瘤胃降解中,对照组厚壁组织的次生壁瘤胃降解变化不明显;处理组与对照组厚壁组织的初生壁、表皮组织没有降解。     

秸秆氨化设备的设计与规划研究项目在京通过鉴定

<正> 北京农业工程大学受农业部畜牧兽医司委托承担的《秸秆氨化设备的设计与规划》课题,历经两年时间现已接任务要求完成,于1990年9月7日在北京通县通过了应用科技成果鉴定。该课题完成的主要内容:①县级秸秆氨化站规划;②秸秆氨化设备(运氨及施氨工具、计量仪器等)的成套设计与试制;③氨化炉的设计与试制;④培训和推广秸秆氨化技术的成套资料;⑤秸秆氨化安全技术操作规程。鉴定认为:县级秸秆氨化站的规划力案管理,符合我国农村实际,对今后建站有重要指导意义;     

我国秸秆氨化技术及设备概况

<正> 作物的秸秆主要是由植物的细胞壁组成。细胞壁的基本成分是纤维素、半纤维素及木质素。纤维素和半纤维素可以通过瘤胃微生物的作用为反刍动物消化利用,加上细胞的内容物,从理论上说,占秸秆于物质80％以上的成分是可以被消化利用的。但是由于纤维素、半纤维素在细胞壁中是与木质素、硅等以复合体的形式存在,使得实际消化率一般只有40％。将秸秆进行氨化处理,可以提高秸秆的消化率,从而提高秸秆的营养价值。其基本原理如下:首先,氨的水溶液——氢氧化铵呈碱性,它对秸秆的碱化作用可以使纤维素、半纤维素与木质素分离,引起细胞壁膨胀,结构变得疏松,使秸秆易于消化,其次,氨与有机物形成醋酸铵,是一种非蛋白氮化合物,是反刍家畜瘤胃微生物的营养源;它能     

氨化处理对秸秆的作用机理

近年来,我国的秸秆氨化技术取得了较大的进展,氨化处理可以改变秸秆的物理、化学和组织结构特性,显著提高秸秆的营养价值和反刍动物对秸秆的消化率。本文在前人研究的基础上,结合生物、物理、化学等多方面的知识,得出氨化对秸秆作用机理的综合描述,对秸秆氨化条件的提供,氨化效率的提高及氨化技术的改进具有指导意义。     

推广氨化秸秆的经济性分析

1我国氨化秸秆的研究推广现状及前景我国自80年代中期开展氨化秸秆的研究与推广以来，已取得令人瞩目的成绩。1993年氨化秸秆数量超过350万吨，近年来累计已突破1500万吨。这无疑为我国调整畜牧业生产结构，发展节粮型畜牧业做出了一定的贡献。1987年以来，农业部与世界粮农组织（FAO）以及联合国计划开发署（UNDP）合作，先后在我国完成两期氨化秸秆技术研究与推广项目，使我国在氨化秸秆的处理技术、质量评定以及将氨化秸秆作为肉牛基础日粮的饲喂体系建立等方面都取得了成熟的经验。1993年10月“利用当地资源发展畜牧业生产国际会议”…     

秸秆微贮饲料研究进展

主要讨论了国内外细菌接种物的现状,秸秆微贮饲料的概念,秸秆在微贮过程中微生物的变化动态,家畜对微贮饲料采食量与消化率,微贮饲料对家畜生产性能的影响及对氨化饲料对比研究等。结果表明:微贮后的秸秆全面优于未处理秸秆;与氨化处理饲料比较,微贮秸秆粗蛋白质含量低于氨化秸秆,但采食量和日增重均高于氨化秸秆,成本亦比氨化处理低。     

粗饲料加工的理想设备──秸秆揉搓机

辽宁凤城东风机械厂在农业部和北京农业工程大学大力协助下，研制生产了粗饲料加工的理想设备─秸秆揉搓机，并于1993年8月通过了辽宁省科委组织的科技成果鉴定和投产鉴定。目前秸秆利用，一是用铡草机将秸秆横向切断直接喂牲畜，吃净率只有70％，造成很大浪费。二是将秸秆铡切后，进行氨化处理喂牲畜。经试验，使用揉搓机将秸秆揉搓成丝条状，直接喂牲畜，吃净率可提高到90％以上。使用揉搓机将秸秆揉搓成柔软的丝条状后进行氨化，不仅易氨化，且可进一步提高吃净率。秸秆揉搓机的工作原理是将物料送进喂入槽，在锤片及空气流的作用下，进…     

尿素的合理利用(续)

三、用尿素氨化粗饲料1.复合氨化方法一般作物秸秆发饲用价值很低,仅含有3～5%粗蛋白质,35～40%是组纤维,其物质的消化率仅35～45%。用来喂牛羊,其进食量约为体重的1.5kg/100kgw,不能满足营养需要。但用物理和化学方法处理后破坏秸秆细胞壁中木质素、半纤维素和纤维素的复合结构,可使这些物质部分或全部溶解。同时还会使秸秆中的纤维素膨胀,增加纤维素之间的空隙度与消化酶接触面积,使秸秆的有机物消化率提高到青贮饲料消化水平的66～70%。早期的方法是用NaOH处理,但成本高,Na~+又会污染环境,造成土壤碱化,近年该法已少用,逐步为氨化法所代替。氨化法如用液氨,就需要钢制容器密闭保存和运输,使用麻烦,成本也高。所以近来多用尿素,尿素在秸秆中的脲酶作用下分     

Effects of dietary supplementation of bentonite and Saccharomyces cerevisiae cell wall on acute-phase protein and liver function in high-producing dairy cows during transition period

Tropical Animal Health and Production - The aim of this study was to investigate the efficacy of dietary endotoxin binders [bentonite (BEN) and Saccharomyces cerevisiae cell wall (SCW)] on...     

酵母壁多糖对断奶仔猪肠道挥发性脂肪酸和微生物菌群的影响

本研究旨在探讨饲粮中添加酵母壁多糖对断奶仔猪肠道挥发性脂肪酸和微生物菌群的影响。试验采用单因素试验设计方法,选取180头遗传背景一致、健康状况良好、胎次和体重接近的21日龄断奶仔猪,随机分为4个组,每组5个重复,每个重复9头猪。4个组试验猪分别饲喂对照饲粮(未添加酵母壁多糖)、0.15%酵母壁多糖饲粮、0.30%酵母壁多糖饲粮和0.45%酵母壁多糖饲粮。试验期21 d。结果表明:1)与对照组相比,饲粮中添加0.15%、0.30%和0.45%酵母壁多糖显著提高了仔猪结肠乙酸的含量(P0.05);其中,0.30%和0.45%酵母壁多糖还显著提高了结肠丙酸、丁酸以及总挥发性脂肪酸的含量(P0.05),且二者之间差异不显著(P0.05)。2)与对照组相比,饲粮中添加0.15%、0.30%和0.45%酵母壁多糖显著降低了盲肠沙门氏菌和大肠杆菌数量(P0.05),且0.30%和0.45%酵母壁多糖组之间差异不显著(P0.05)。由此可知,酵母壁多糖可提高仔猪肠道挥发性脂肪酸含量,并改善肠道微生物菌群结构,根据回归方程预测,酵母壁多糖在仔猪饲粮中的适宜添加水平为0.31%~0.40%。     

Clinical features and outcome of dermal squamous cell carcinoma in 193 dogs (1987‐2017)

Squamous cell carcinoma (SCC) is a frequently recognized dermal tumour in dogs and has been described as a common pathology induced by solar ultraviolet radiation exposure. Little has been published about this neoplasm with regard to clinical features and outcome in dogs. This retrospective study included 193 dogs from a single institution histopathologically diagnosed with SCC of the dermis. Thirty‐eight percent of all dogs had documented histopathologic actinic change. The overall median survival time was 1004 days, with the population demonstrating actinic change associated with a significantly longer survival time (median 1359 days, range 16‐3530 days) compared to dogs without actinic change (median 680 days, range 16‐3066 days) and this achieved significance on multivariate analysis (hazard ratio 0.42, 95% confidence interval 0.193‐0.930, P = 0.032). These data demonstrate increased survival of dogs with SCC demonstrating actinic change over those with non‐actinic SCCs, and purports long‐term survival for these animals. Dogs received a variety of treatment approaches as a retrospective study, and future prospective studies will be necessary to investigate whether adjunct therapies such as radiation or chemotherapy offer improvement in survival for dermal SCC in the dog.     

蜂王浆生产新技术的研究--三种生产王浆用特种巢脾对蜂王产卵量影响

对三种自制的用于蜂王浆机械化生产的产卵用特种巢脾进行了测试,在不同的蜂群群势,奖励饲喂时间和多王技术条件下对吸引蜂王的产卵量进行了比较.结果表明,(1)自制六角形巢房的巢脾较另两种圆筒形巢房巢脾对蜂王更具吸引力;(2)采用5足框的蜂群作为产卵群,并在插入自制六角形巢房巢脾的前2d,可获得较高的产卵量;(3)采用2只蜂王产卵可在6h内基本产满特种巢脾,从而获得日龄基本一致的卵或幼虫.     

Effect of antimicrobial agents on the production and release of shiga toxin by enterotoxaemic Escherichia coli isolates from pigs

Edema disease (ED) of pigs is an enterotoxaemic disease caused by enterotoxaemic Escherichia coli (ETEEC) infection. Antimicrobial therapy for pigs with ED is controversial because it may induce death of sickish piglets. In this study, we investigated the effects in vitro of 7 antimicrobial agents, ampicillin, gentamicin, colistin, bicozamycin, fosfomycin, sulfamethoxazole-trimethoprim and enrofloxacin, on the release and production of shiga toxin (Stx) 2e by ETEEC strains. We found that more Stx 2e accumulated in the bacterial cells than was released into supernatant. Associated with inhibition of cell wall synthesis, the exposure to ampicillin or fosfomycin increased the release of Stx 2e. The production levels of Stx 2e in all antimicrobial-treated cultures were equal to the level in the control or less than in the control. These results suggest that cell wall synthesis inhibitors, such as ampicillin and fosfomycin, may change for the worse in the signs in ETEEC infectious pigs. On the other hand, gentamicin, colistin, bicozamycin and enrofloxacin may be useful for the treatment of pigs with ED.     

Mast cells and IgE-bearing cells in lungs of RAO-affected horses

Recurrent airway obstruction (RAO) is a common condition in stabled horses characterised by small airway inflammation and obstruction following exposure of susceptible horses to mouldy hay and straw. The aim of the present study was to investigate whether lung tissue from horses with RAO contains higher numbers of IgE-protein positive (+) cells and mast cells compared to controls after mouldy hay challenge. Furthermore, mast cell subtypes in lung tissue were investigated. IgE+ cells were detected in most lung tissue samples but no significant differences between RAO-affected and control horses were found. In the wall of the bronchi and bronchioli of both RAO-affected and control horses, mainly chymase+ mast cells (MC(C)) were present (85% in the bronchial wall and 77% in the wall of the bronchioli), while 73% of the mast cells (MC) around blood vessels were tryptase+ mast cells (MC(T)). No double stained MCs were detected. RAO-affected horses had significantly more MC(C) than controls in the wall of the bronchi (median=7.6 and 1.7 cell/mm(2), respectively, P< or =0.05). They also showed a tendency for more MC(C) in the wall of the bronchioli than controls (median=21 and 2.9 cells/mm(2), respectively, P=0.07) but there were no differences in MC(T) numbers. The data suggest an involvement of MC(C) in the pathogenesis of RAO. Independently of the clinical diagnosis, there was a significant relationship between high MC(C) numbers in the bronchial wall and lung fibrosis, suggesting that these MC(C) may be involved in tissue remodelling. Furthermore, high MC(C) numbers were also associated with increased infiltration with lymphocytes and neutrophils.     

酵母壁多糖对断奶仔猪外周血免疫和肠道免疫的影响

本试验旨在探讨饲粮中添加酵母壁多糖对断奶仔猪外周血免疫和肠道免疫的影响。采用单因素试验设计方法,选取21日龄遗传胎次、体重接近的断奶仔猪180头,随机分为4个组,每组5个重复,每个重复9头猪。4组分别饲喂饲粮中添加0(对照组)、0.15%、0.30%和0.45%酵母壁多糖的试验饲粮。试验期21 d。结果表明:1)与对照组相比,饲粮中添加0.15%、0.30%和0.45%酵母壁多糖显著提高了断奶仔猪血清免疫球蛋白A(IgA)含量(P0.05),饲粮中添加0.30%和0.45%酵母壁多糖显著提高了断奶仔猪血清免疫球蛋白G(IgG)含量(P0.05)。2)与对照组相比,饲粮中添加0.15%、0.30%和0.45%酵母壁多糖显著降低了断奶仔猪血清干扰素-γ(IFN-γ)含量(P0.05),饲粮中添加0.30%酵母壁多糖显著提高了断奶仔猪血清白细胞介素-10(IL-10)的含量(P0.05)。饲粮中添加酵母壁多糖对断奶仔猪血清白细胞介素-2(IL-2)、白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)含量均无显著影响(P0.05)。3)与对照组相比,饲粮中添加0.30%和0.45%酵母壁多糖显著提高了断奶仔猪回肠CD4~+淋巴细胞含量(P0.05),饲粮中添加酵母壁多糖能一定程度提高断奶仔猪回肠CD8~+和CD20~+淋巴细胞含量,但差异不显著(P0.05)。由此可知,酵母壁多糖能一定程度提高断奶仔猪外周血免疫和肠道免疫,缓解断奶应激。     

酵母细胞表面展示技术

酵母细胞表达体系具备较为完善的蛋白质翻译后修饰和分泌的机制.以酵母为基础的细胞表面展示技术是一项新兴的真核蛋白展示技术,已成功应用于蛋白质识别、蛋白质的固定化和定向进化研究,成为了蛋白质工程研究的重要工具.根据与酵母细胞壁的外源目的蛋白融合部位的不同,酿酒酵母表面展示系统主要分为凝集素系统和絮凝素系统2大系统.将该技术...     

ULTRASONOGRAPHIC APPEARANCE OF URETHRAL TRANSITIONAL CELL CARCINOMA IN TEN DOGS

The mucosal margin of the urethra is best assessed by positive contrast urethrography, but ultrasonography offers complementary information such as urethral wall thickness and size of medial iliac lymph nodes. Ultrasonography of the urethra is quick, noninvasive and does not require sedation or general anesthesia. In patients with complete urethral obstruction, ultrasonography may be the only way to image the urethra. Twelve dogs which were presented to Tufts University School of Veterinary Medicine with clinical signs referable to the urinary bladder, urethra or vagina were examined ultrasonographically. Seven were neutered females and five were neutered males. Each dog had a hyperechoic, nonshadowing line at the epithelial surface of the proximal urethra. In the seven female patients and one of the males, the urethral wall was also thick and hypoechoic to surrounding tissue. In the other males, the urethral epithelial changes were at the level of the prostate, and the limits of the urethra were not visible. In six dogs, the urethral change was the only abnormality seen, while in six, bladder wall, bladder luminal and/or prostatic parenchymal changes were also detected. Three patients had hydronephrosis, and one had enlarged medial iliac lyumph nodes. Biopsies were obtained via suction with urinary catheterization (n = 6), exploratory celiotomy (n = 3), urethroscopy (n = 2), or at post-mortem (n = 1). A histopathologic diagnosis of urethral transitional cell carcinoma was obtained in ten dogs. The ultrasonographic appearance was not pathognomonic for transitional cell carcinoma, as one dog with transitional cell dysplasia and one dog with severe ulcerative and necrosupperative cystitis and urethral stricture had similar findings.