马杜霉素发酵法生产工艺的研究     

赵子刚  夏黎明 《中国兽药杂志》2004,38(1):47-50

马杜霉素是一种应用广泛的兽用抗球虫抗生素.以马杜霉拉放线菌(Actinomadura Yumanense sp.)ZU-M3为生产菌株,通过摇瓶实验获得较适宜的发酵条件:发酵培养基含葡萄糖7%,豆饼粉1.2%,玉米浆1.2%,NaCl 0.3%,CaCO3 0.1%,K2HPO3 0.03%,Fe2(SO4)3 0.01%,初始pH为6.6,发酵温度为34 ℃.用3L发酵罐做放大试验,通气速率为0.12 m3/h,搅拌速率600 r/min,发酵8 d 菌液发酵单位达到8 336 μg/mL.该研究结果对于大规模的工业化生产具有指导意义.  相似文献   

禽大肠杆菌高密度发酵与溶氧关系的研究   总被引：2，自引：0，他引：2  

宋卉王树迎  邹维华沈志强 《黑龙江畜牧兽医》2004,(1):12-13

利用GUJS—10C小型发酵罐分批培养禽大肠杆菌，通过平板计数、比浊计数的方法，对大肠杆菌高密度发酵中细菌生长与溶氧的关系进行分析。结果表明：溶氧的规律性变化能够反映大肠杆菌生长的规律，即在细菌生长的适应期细菌数量较少，耗氧量少，溶氧曲线最高；随着发酵时间的增加，细菌不断增多，耗氧量也随之增加，溶氧曲线下降；达到对数生长期，曲线最低；进入稳定期，曲线趋于平稳；到发酵后期，细菌进入衰老期，溶氧曲线略有上升，这时可终止发酵。  相似文献   

Effect of cyclodextrin diallyl maleate on methane production, ruminal fermentation and microbes in vitro and in vivo   总被引：1，自引：0，他引：1  

Zeenat Ara LILA  Nazimuddin MOHAMMED  Noriko TATSUOKA  Shuhei KANDA  Yuzo KUROKAWA  Hisao ITABASHI 《Animal Science Journal》2004,75(1):15-22

Effects of β‐cyclodextrin diallyl maleate (CD‐M) on methane production, ruminal fermentation and digestibility were studied both in vitro and in vivo. In in vitro study, diluted ruminal fluid (30 mL) was incubated anaerobically at 38°C for 6 and 24 h with or without CD‐M using hay plus concentrate (1.5:1) as a substrate. The CD‐M was added at different concentrations (0, 1.25, 2.5, 5.0 and 7.5 g/L). The pH of the medium and numbers of protozoa were not affected by the addition of CD‐M. Total volatile fatty acids were increased and ammonia‐N was decreased, molar proportion of acetate was decreased and propionate was increased (P < 0.05) by CD‐M. Methane was inhibited (P < 0.05) by 14–76%. The effect of CD‐M on methane production and ruminal fermentation was further investigated in vivo using four Holstein steers in a cross‐over design. The steers were fed Sudangrass hay and concentrate mixture (1.5:1) with or without CD‐M (2% of feed dry matter) as a supplement. Ruminal proportion of acetate tended to decrease and that of propionate was increased (P < 0.05) 2 h after CD‐M dosing. Total viable counts, cellulolytic, sulfate reducing, acetogenic bacteria and protozoa were unaffected while methanogenic bacteria were decreased (P < 0.05) by CD‐M. The plasma concentration of glucose was increased, whereas that of urea‐N was decreased (P < 0.05). Methane was inhibited (P < 0.05) from 36.4 to 30.1 L/kg dry matter intake by the addition of CD‐M. Apparent digestibilities of dry matter and neutral detergent fiber were not affected while that of crude protein was increased (P < 0.05) in the medicated steers. These data suggested that dietary supplementation of CD‐M decreased methane production and improved nutrient use.  相似文献   

Effects of cyclodextrin-iodopropane complex on methane production, ruminal fermentation and microbes, digestibility and blood metabolites in steers     

Nazimuddin MOHAMMED  Zeenat Ara LILA  Noriko TATSUOKA  Koji HARA  Katsuhiko MIKUNI  Kozo HARA  Shuhei KANDA  Hisao ITABASHI 《Animal Science Journal》2004,75(2):131-137

The effects when adding cyclodextrin‐iodopropane complex (CD‐IP) to a diet, on ruminal fermentation and microbes, digestibility, blood metabolites and methane production, were evaluated using four Holstein steers in a cross‐over design. The steers were fed Sudangrass hay plus concentrate mixture at a ratio 1.5:1, and CD‐IP (1% of dry matter) was given twice daily by mixing with concentrate mixture. Rumen and blood samples were collected at 0, 2, and 5 h after morning dosing. Ruminal pH and numbers of protozoa were unaffected by CD‐IP treatment. Ruminal molar proportion of acetate was decreased (P < 0.05), and propionate was increased (P < 0.01) at 2 h after CD‐IP dosing. Proportion of butyrate was increased (P < 0.05) and ammonia‐N was decreased (P < 0.05) at 2 and 5 h after CD‐IP dosing. Adding CD‐IP had no effect on the feed intake and digestion of nutrients. Plasma glucose was increased and urea‐N was decreased (P < 0.05) at 2 and 5 h after CD‐IP dosing. Methane production was decreased (P < 0.05) by approximately 18% in the treatment steers. Numbers of methanogenic bacteria were decreased (P < 0.05), while total viable counts, cellulolytic, sulfate reducing and acetogenic bacteria were unaffected. The present results are the first to show that CD‐IP can partially inhibit in vivo ruminal methanogenesis without adverse effects on digestion of nutrients.  相似文献   

应用遥感技术对内蒙古镶黄旗草原分类的研究   总被引：1，自引：1，他引：1  

单丽燕  刘荣堂  余鸣  贠旭疆  李新一 《草原与草坪》2005,(1):38-42

研究了遥感技术在内蒙古镶黄旗草原资源调查中的应用,探讨了利用TM影像进行草原资源专题信息提取的整个过程,包括几何校正、镶嵌、特征提取和训练区的选择,采用常规的监督分类和非监督分类方法,对图像进行了分类,同时对分类结果进行了校验。  相似文献   

丝兰皂甙对绵羊瘤胃发酵及血液生化指标的影响   总被引：1，自引：0，他引：1  

刘春龙  李杰  唐彦君 《畜牧兽医学报》2005,36(8):784-788

选用12只装有永久性瘤胃瘘管的成年雄性东北细毛羊，采用随机区组试验设计，分别饲喂0、100、200、300mg／kg水平丝兰皂甙，研究其对瘤胃发酵及血液生化指标的影响。对试羊采食后的0、2、4、6、8h瘤胃内环境指标进行测定，各组在同一时间点pH无显著差异（P〉0．05），但总体上随着丝兰皂甙添加水平的上升，pH随时间变化有变缓趋势；300mg／kg组较对照组4h和6h乙酸浓度下降15．1％和19．8％，丙酸浓度则提高22．7％和22．9％，差异显著（P〈0．05），各组总挥发性脂肪酸浓度差异不显著（P〉0．05）；100、200、300mg／kg组对氨的抑制率分别为17．17％、29．84％和27．12％，200mg／kg组较对照组差异显著（P〈0．05）；28d后，测定试羊血液生化指标，各组均处正常生理范围内且差异不显著（P〉0．05）。  相似文献   

Effect of oak (Quercus persica) acorn level on apparent digestibility,ruminal fermentation,nitrogen balance and urinary purine derivatives in pregnant goats          下载免费PDF全文

H. Jafari  F. Fatahnia  A. Khatibjoo  G. Taasoli  H. Fazaeli  S. Varmaghany 《Journal of animal physiology and animal nutrition》2018,102(4):882-891

The aim of this experiment was to investigate the effect of dietary oak (Quercus persica) acorn (OA) level on dry matter intake (DMI), apparent nutrient digestibility, nitrogen (N) utilization, ruminal fermentation, protozoa population and urinary purine derivatives (PD) during the last 60 days of goat pregnancy. Twenty‐four multiparous pregnant goats (41.7 ± 2.3 kg BW) were assigned to one of three experimental diets consisted of control diet (C, without OA) and diets containing 20 (OA₂₀) or 40 g/100 g of OA (OA₄₀) on a DM basis in a completely randomized block design. Goats fed OA₄₀ had lower DMI (p < .01), DM (p < .01), OM (p < .01) and NDF (p < .05) digestibility, ruminal NH₃‐N concentration (p < .01), N intake (p < .01) and N retention (p < .01). Crude protein digestibility and ruminal acetate and total volatile fatty acid (VFA) concentration were lower in animals fed OA‐contained diets (p < .01), whereas ruminal propionate concentration was higher in goats fed the C diet (p < .01). Animals fed OA₄₀ had higher faecal N excretion and lower urinary N excretion (p < .01). Urinary PD was lower in goats fed diets containing OA in relation to those fed the C diet (p < .01). Total protozoa population decreased linearly with increasing OA level in the diet (p < .05). These results suggest that feeding OA, especially high level, has negative impacts on DMI, nutrient digestibility, VFA concentration, N retention and urinary PD excretion that may have adverse effects on metabolism and performance of pregnant goats.  相似文献   

Effects of concentrate‐to‐forage ratios and 2‐methylbutyrate supplementation on ruminal fermentation,bacteria abundance and urinary excretion of purine derivatives in Chinese Simmental steers          下载免费PDF全文

C. Wang  Q. Liu  G. Guo  W. J. Huo  C. X. Pei  S. L. Zhang  H. Wang 《Journal of animal physiology and animal nutrition》2018,102(4):901-909

This study evaluated the effects of dietary concentrate levels and 2‐methylbutyrate (2MB ) supplementation on performance, ruminal fermentation, bacteria abundance, microbial enzyme activity and urinary excretion of purine derivatives (PD ) in steers. Eight ruminally cannulated Simmental steers (12 months of age; 389 ± 3.7 kg of body weight) were used in a replicated 4 × 4 Latin square design with a 2 × 2 factorial arrangement. Moderate‐concentrate (400 g/kg diet [MC ]) or high‐concentrate (600 g/kg diet [HC ]) diets were fed with or without 2MB (0 g/day [2MB ?] or 15.0 g/day [2MB +]). Dry matter intake and average daily gain increased, but feed conversion ratio decreased with the HC diet or 2MB supplementation. Ruminal pH decreased, but total volatile fatty acid increased with the HC diet or 2MB supplementation. Molar proportion of acetate and acetate‐to‐propionate ratio decreased with the HC diet, but increased with 2MB supplementation. Propionate molar proportion and ruminal NH ₃‐N content increased with the HC diet, but decreased with 2MB supplementation. Neutral detergent fibre degradability decreased with the HC diet, but increased with 2MB supplementation. Crude protein degradability increased with the HC diet or 2MB supplementation. Abundance of Ruminococcus albus , Ruminococcus flavefaciens , Fibrobacter succinogenes and Bufyrivibrio fibrisolvens as well as activities of carboxymethyl cellulase, cellobiase, xylanase and pectinase decreased with the HC diet, but increased with 2MB supplementation. However, abundance of Prevotella ruminicola and Ruminobacter amylophilus as well as activities of α‐amylase and protease increased with the HC diet or 2MB supplementation. Total PD excretion also increased with the HC diet or 2MB supplementation. The results suggested that growth performance, ruminal fermentation, CP degradability and total PD excretion increased with increasing dietary concentrate level from 40% to 60% or 2MB supplementation. The observed diet × 2MB interaction indicated that supplementation of 2MB was more efficacious for improving growth performance, ruminal fermentation and total PD excretion with promoted ruminal bacteria abundance and enzyme activity in the MC diet than in the HC diet.  相似文献   

Interaction between the sequence of feeding of hay and concentrate,and boiling of barley on feed intake,the activity of hydrolytic enzymes and fermentation in the hindgut of Arabian mares          下载免费PDF全文

A. Kiani  F. Hoseini  P. Ghorbaninejad  A. Azarfar  M. Kreuzer  A. Azizi 《Journal of animal physiology and animal nutrition》2018,102(3):810-817

The interaction between the sequence of feeding of hay and concentrate and the hydrothermal processing of barley in alleviating concentrate effects on intake, and hindgut fermentation in horses was tested. Six Arabian mares (4–10 years of age, 410 ± 35 kg body weight) were used to evaluate the effects of feeding sequence (FS) and type of barley (TB) on intake, and faecal volatile fatty acids (VFA), activities of α‐amylase (AA: EC 3.2.1.1), carboxymethyl cellulase (CMCase: EC 3.2.1.4), microcrystalline cellulase (MCCase: EC 3.2.1.91) and general filter paper degrading activity (FPD). Mares were offered a ration of air‐dried alfalfa and concentrate (70:30 as‐fed) in four subsequent periods of 14 days including 8 days of adaptation and 6 days of sampling. In each period and each meal, mares received concentrate either 30 min after (HC) or 30 min before (CH) alfalfa hay. Barley was either milled or boiled in water. Rectal samples were grabbed directly from rectum once per period. Mares subjected to CH had higher dry matter intakes than mares under HC regime. The acetate:propionate ratio (A:P ratio) in rectal content was higher with CH than HC. The AA activity was higher under CH than under HC. Mares fed boiled barley had lower rectal concentrations of VFA and propionate and a higher A:P ratio than mares fed milled barley. Furthermore, the rectal content showed a higher MCCase activity but a lower AA activity when mares were fed boiled compared with milled barley. Interactions between FS and TB were observed with respect to CMCase activity, and concentrations of propionate and valerate. In conclusion, the present results suggest that both, feeding concentrate before hay and boiling the barley, might improve the hindgut environment in Arabian mares, and that the two measures were mostly additive and sometimes even synergistic.  相似文献   

芦苇和白刺空间格局对青土湖生态输水的响应     

陈政融  刘世增  刘淑娟  孙涛 《草业科学》2015,(12):1960-1968

石羊河尾闾湖——青土湖位于腾格里沙漠和巴丹吉林沙漠边缘,是阻隔两大沙漠合围的生态屏障。自2010年开始连续5年向青土湖进行生态输水并形成一定规模的水面,对促进区域植被恢复和保护民勤湖区绿洲具有重要的生态意义。本研究选用2008年、2010年、2011年、2012年、2013年、2014年的高分辨率遥感影像资料同时结合研究区的实地调查资料,对形成人工水面的面积和输水前后的芦苇(Phragmites australis)、白刺(Nitraria tangutorum)群落面积进行了统计分析和对比。结果表明,5年连续输水形成叠加效应,水面面积成倍增加,芦苇相对频度逐年增加和白刺相对频度逐年减少,芦苇群落(Form.P.australis)面积增加了8.43倍,临接水域和水域中的白刺群落(Form.N.tangutorum)消失,白刺面积减少了68.00%。人工输水促进了芦苇群落依水蔓延,镶嵌于水域成片分布;距水面50 m范围的白刺群落由连续成片成点状。输水促进了湿生植物生长,导致荒漠植物种退化。  相似文献