化学添加剂对有氧胁迫下湿贮玉米发酵品质和有氧稳定性的影响

为研究苯甲酸钠、山梨酸钾和亚硝酸钠组成的化学添加剂对有氧胁迫处理的湿贮玉米发酵品质和有氧稳定性的影响。以35%和50%含水量的湿贮玉米为原料，设置对照组(无添加)、添加组1(2mL·kg^-1)、添加组2(4mL·kg^-1)在湿贮期设置不同时期有氧胁迫处理分别为:前期有氧胁迫处理(1~7d，Early air stress，EAS)、后期有氧胁迫处理(22~28 d，Later air stress，LAS)、全程有氧胁迫处理(1~28d，Full air stress，FAS)，28d后分析发酵品质、有氧稳定性以及有氧暴露7d后的发酵品质。结果表明：与对照组相比，添加组2的有机酸浓度最高，干物质损失最少，而且有氧稳定性最高。4mL·kg^-1的化学添加剂还显著抑制了酵母菌和大肠杆菌的生长。因此，化学添加剂明显消除了氧气的负面影响，并延长了有氧胁迫条件下的有氧稳定时间。     

Hulless barley and β-glucanase affect ileal digesta soluble β-glucan molecular weight and digestive tract characteristics of coccidiosis-vaccinated broilers

Exogenous β-glucanase (BGase) in barley-based feed has been shown to reduce digesta viscosity in chickens, and thereby improve performance. Less well studied is the potential for BGase to convert barley β-glucan into low molecular weight carbohydrates, which might influence digestive tract function and enteric disease. Coccidiosis-vaccinated broiler chickens were fed graded levels of hulless barley (HB) and BGase to determine their effects on β-glucan depolymerization and digestive tract characteristics. Broilers were fed high β-glucan HB (0%, 30% and 60% replacing wheat) and BGase (0%, 0.01% and 0.1%) in a 3 × 3 factorial arrangement. A total of 5,346 broilers were raised in litter floor pens and vaccinated for coccidiosis on d 5. Each treatment was assigned to 1 pen in each of 9 rooms. The significance level was set at P ≤ 0.05. At both 11 and 33 d of broiler ages, peak molecular weight of β-glucan in ileal digesta decreased with increasing BGase for 30% and 60% HB. The maximum molecular weight for the smallest 10% β-glucan molecules (MW-10%) decreased with BGase at both ages for 30% and 60% HB; for birds fed 0% HB, only 0.1% BGase decreased MW-10%. The 0.1% BGase increased caecal short chain fatty acids (SCFA) compared to the 0.01% BGase at d 11 only for the 60% HB. Ileal pH increased with increasing HB and BGase at d 11 and 33. Caecal pH was lower for 0.1% BGase than 0% BGase for 60% HB at d 11. Relative mRNA expression of interleukin 6 (IL-6) and IL-8 in the ileum increased with 0.1% BGase at d 11 and 33, respectively, whereas expression of ileal mucin 2 (MUC2) decreased with 0.1% BGase at d 33. In the caeca, interactions between HB and BGase were significant for monocarboxylate transporter 1 (MCT1) and mucin 5AC (MUC5AC) on d 11, but no treatment effects were found at d 33. In conclusion, BGase depolymerized high molecular weight β-glucan in HB in a dose-dependent manner. Hulless barley and BGase did not increase SCFA concentrations (except for 60% HB with 0.1% BGase at d 11) and caused minor effects on digestive tract histomorphological measurements and relative mRNA gene expression.     

链霉菌F0107液体发酵产木聚糖酶条件的优化

运用透明圈法从土样中筛选出产木聚糖酶放线菌80余株.对其中一株产酶情况较稳定的链霉菌菌株F0107进行了液体发酵的碳源、氮源、初始pH值、摇床转速及培养温度等条件的优化.实验表明,此菌株最适碳源为玉米芯水不溶性木聚糖,最适氮源为酵母浸膏与蛋白胨的复合氮源,最适初始pH值为5.0,最适产酶温度和最适摇床转速分别为32℃和140 r/min.质量分数为0.4%的吐温80使菌株木聚糖酶产量提高41%,发酵条件优化后,链霉菌F0107所产的木聚糖酶活力达332.17 U/mL,产量是优化条件前的2.5倍.在此条件下链霉菌F0107主要产生相对分子质量约为38.9 ku和24.4 ku的木聚糖酶.     

环境温度对发酵床养殖公猪繁殖性能的影响

微生物发酵床养殖是一种生态养殖模式,在冬天具有很好的保暖作用,减少了日粮的损耗,但在夏天,缺少散热的功能,对育肥猪和种猪的养殖影响较大。实验对某微生物发酵床生态养猪场的4头种公猪,通过连续观测公猪舍环境温度、垫料温度及公猪的精神状态,检测公猪血液生化指标、精子活率、精子质量、精子密度及生化指标项目。结果发现1号公猪的总蛋白水平较高,其它生化指标差异不显著;4头公猪中只有4号公猪精子活率达到70%,其余公猪精液中精子活率低于10%,大量死精。结果表明微生物发酵床养殖对公猪繁殖性能的影响较大。     

混合型乳酸菌制剂对不同品种青饲玉米青贮品质的影响

试验旨在研究混合型乳酸菌制剂对会宁县不同品种青饲玉米青贮品质的影响，为优质青贮玉米的推广及其加工调制提供参考依据。试验采用双因子交互设计（品种、添加剂），选择种植在会宁的14个青饲玉米品种，进行桶装青贮，每个品种分两个青贮处理，即混合型乳酸菌制剂组（Sila-Max）、空白对照组（CK），发酵60 d后分析对比各品种营养成分及发酵特性。结果表明：‘蜀玉201’的WSC和Starch含量显著高于其他品种，‘利单295’的ADF、NDF、Ash含量均较低，‘宁单34号’、‘金凯3号’LA含量显著高于其他品种。本研究表明，品种和乳酸菌制剂会影响青饲玉米青贮品质，乳酸菌制剂能增加部分品种Starch，WSC，ESC，LA，AA含量，同时降低NH₃-N含量，自然青贮下青贮品质较好的品种有‘利农368’、‘利单295’，加入乳酸菌制剂后青贮品质较好的品种有‘宁单34号’、‘金穗715’、‘蜀玉201’、‘豫青贮23’、‘桂青贮1号’。     

添加不同发酵菌剂对巨菌草青贮饲料营养品质的影响

为探索发酵菌剂在巨菌草青贮中的效果，以不添加任何菌剂为对照，研究了3种发酵菌剂(EM菌液、聚能发酵剂、酶菌复合剂)对巨菌草青贮发酵品质的影响。结果表明，在巨菌草中添加微生物发酵菌剂后，一定程度上改善了青贮饲料的品质，使巨菌草青贮饲料pH降低，中性洗涤纤维减少，营养成分得到较好的保存。其中以每1 t 巨菌草揉丝原料添加2 L EM菌液处理组效果最好，不仅降低了巨菌草青贮饲料的pH，而且提高了粗蛋白含量，是3种供试发酵菌剂中的最优菌剂。     

鸡粪堆肥系统的设计原则

堆肥系统的设计及设备配置关乎产品品质，系统地研究鸡粪堆肥，特别是适用于工厂化的规模堆肥，要综合考虑各个要素，遵循一定的设计原则，针对性地设计一套堆肥系统，生产出满足商品有机肥料标准的合格产品。      

添加不同发酵菌剂对巨菌草青贮饲料营养品质的影响

为探索发酵菌剂在巨菌草青贮中的效果，以不添加任何菌剂为对照，研究了3种发酵菌剂(EM菌液、聚能发酵剂、酶菌复合剂)对巨菌草青贮发酵品质的影响。结果表明，在巨菌草中添加微生物发酵菌剂后，一定程度上改善了青贮饲料的品质，使巨菌草青贮饲料pH降低，中性洗涤纤维减少，营养成分得到较好的保存。其中以每1 t 巨菌草揉丝原料添加2 L EM菌液处理组效果最好，不仅降低了巨菌草青贮饲料的pH，而且提高了粗蛋白含量，是3种供试发酵菌剂中的最优菌剂。