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1.
旨在阐释奶牛日粮添加淀粉对奶牛乳脂及瘤胃细菌菌群变化的影响。选取4头体况相近、健康的泌乳期中国荷斯坦奶牛,试验开始前以基础日粮饲喂并作为对照,饲喂7 d;试验期每头奶牛日粮中添加1.5 kg·d-1玉米淀粉,饲喂15 d。结果表明,日粮中添加淀粉后,牛奶乳脂率极显著降低(P<0.01)。瘤胃细菌研究表明,在门水平上共检测到28个菌门,玉米淀粉导致瘤胃芽单胞菌门(Gemmatimonadetes)、软壁菌门(Tenericutes)丰度极显著降低(P<0.01),装甲菌门(Armatimonadetes)、酸杆菌门(Acidobacteria)、蓝藻门(Cyanobacteria)丰度显著降低(P<0.05),厚壁菌门(Firmicutes)丰度显著增加(P<0.05)。在属水平上共检测到383个菌属,其中90个菌属发生显著变化。玉米淀粉导致醋酸杆菌属(Acetobacter)、乳酸杆菌属(Lactobacillus)、小球菌属(Pediococcus)、明串珠菌属(Leuconostoc)、毛螺旋菌属-1(Lachnoclostridium-1)、瘤胃球菌属-1(Ruminococcus-1)、普雷沃氏菌属-7(Prevotella-7)等丰度极显著增加(P<0.01),厌氧弧菌属(Anaerovibrio)、肠球菌属(Enterococcus)、栖水菌属(Enhydrobacter)等丰度极显著降低(P<0.01)。本试验结果表明,奶牛日粮中添加一定量的玉米淀粉对瘤胃细菌多样性和种类分布均匀度均无显著影响,但其促进了大部分产酸菌群的增殖。  相似文献   

2.
降铜对植酸酶在断奶仔猪饲粮中应用的影响   总被引：1，自引：0，他引：1  
【目的】为加快仔猪生长和提高饲粮消化率,仔猪饲粮中常常同时添加高剂量铜和植酸酶,但高铜对植酸酶的作用究竟有何影响却仍鲜见报道。研究高铜饲粮中添加植酸酶对仔猪营养物质消化率、生产性能、粪铜和粪磷排放的影响,以及降低铜的添加量对植酸酶作用的影响。【方法】试验选取180头体重9-10 kg长×大二元杂交仔猪,随机分成3组,每组5栏,每栏12头猪,分别饲喂3种试验饲粮中的一种。试验饲粮为玉米-豆粕型饲粮,其营养水平达到或超过NRC(1998)相应阶段猪营养需要量。组1为对照组,饲粮铜添加量为180 mg·kg-1（硫酸铜）,不添加植酸酶;组2和组3为植酸酶试验组,添加500 IU·kg-1植酸酶,组2和3饲粮铜添加量分别为 180和120 mg·kg-1（硫酸铜）。试验预试期3 d,正试期3 w,试验期间仔猪自由采食和饮水,记录采食量,观察腹泻情况,计算试验期间平均日采食量、日增重、料重比和腹泻频率。试验结束前连续3 d以栏为重复单位采集部分新鲜粪样,每100 g新鲜粪样加10 mL的10%乙醇,-20℃保存待测。以酸不溶灰分为参照内标,测定计算营养物质消化率和矿物质表观消化率。【结果】（1）高铜仔猪饲粮中添加植酸酶可使磷表观消化率提高21.12%（组2与组1相比,P＜0.01）,粪磷含量降低4.41%（P=0.09）,腹泻频率降低19.22%（P=0.35）,添加植酸酶对干物质和蛋白表观消化率,采食量、日增重和料重比均无显著影响。（2）两个植酸酶试验组相比,当铜添加量由180 mg·kg-1降低到120 mg·kg-1时,钙、磷表观消化率分别提高13.74%和9.79%（组3与组2相比,P=0.02和P=0.01）,粪磷含量降低18.86%（P＜0.01）,腹泻频率降低25.24%（P=0.25）,降铜对干物质和粗蛋白表观消化率、采食量、日增重和料重比均无显著影响。（3）与高铜无植酸酶组相比,减少铜添加量并且添加植酸酶,可使饲粮的干物质、粗蛋白、钙和磷表观消化率分别提高1.80%、2.84%、17.20%和32.98%（组3与组1相比,P=0.02,P=0.04,P＜0.01和P＜0.01）,腹泻频率降低39.6%（P=0.04）。【结论】现有试验表明,在添加植酸酶的玉米-豆粕型饲粮中,将铜（硫酸铜形式）添加量从180 mg·kg-1 减少到120 mg·kg-1可以显著减少铜对植酸酶的干扰,提高饲粮钙、磷表观消化率,降低粪铜和粪磷含量。  相似文献   

3.
【目的】研究奶牛乳腺炎源大肠杆菌中耶尔森菌HPI携带情况及其与O血清型的关系,并对部分菌株的相关基因序列进行分析。【方法】从中国北京、内蒙古、甘肃、四川、重庆、云南、贵州等7个省市部分地区1 260份临床型和隐性奶牛乳腺炎奶样中分离得到190株大肠杆菌,对分离菌株进行耶尔森菌强毒力岛核心区irp2基因、fyuA基因及HPI毒力岛在大肠杆菌染色体中插入位置的鉴定,分析HPI毒力岛的携带情况及其与分离菌株O血清型之间的关系。【结果】190株大肠杆菌分离株中,irp2基因阳性率为26.31%（50/190）,fyuA基因阳性率为18.94%（36/190）。50株HPI+分离株中检出asn_tRNA_intB 基因32株,阳性率为64%（32/50）。本试验克隆的irp2基因(273 bp）、fyuA基因(1 071 bp）、asn_tRNA_intB基因(1 512 bp）均与已发表序列高度同源,同源性分别在97.1%、98.2%、97.2%以上,且其HPI毒力岛大多位于大肠杆菌染色体的asn_tRNA位点上。【结论】耶尔森菌HPI在奶牛乳腺炎源大肠杆菌中广泛流行分布,但也存在差异,而不同血清型菌株携带HPI的倾向性可能只与特定的血清型有一定的关系。  相似文献   

4.
Myostatin (MSTN) is a negative regulator of skeletal muscle growth and development.  The skeletal muscle in MSTN–/– mice is significantly hypertrophied, with muscle fiber type II increasing significantly while muscle fiber type I decreasing.  However, it is still not clear how the skeletal muscle types change in MSTN–/– pigs, and how the mechanism for MSTN regulates fiber types, especially in large animals like pigs.  This study conducted a comprehensive analysis of the composition of skeletal muscle fibers in MSTN–/– pigs produced in our laboratory.  It was observed that, compared with wild-type (WT) pigs, both the total mass of skeletal muscle and type IIb muscle fibers increased significantly (P<0.01), while the type I and type IIa muscle fibers decreased significantly (P<0.01), in MSTN–/– Meishan pigs.  In addition, to explore the influence of MSTN on muscle fiber type and its regulation mechanism in the embryonic stage, this study selected a few genes (Myf5, Mef2d, MyoD and Six1) associated with muscle fiber type and validated their expression by quantitative RT-PCR.  Herein, it was found that Myh7, Myh2, Myh4 and Myh1 can be detected in the skeletal muscle of pigs at 65 days of gestation (dg).  Compared with WT pigs, in MSTN–/– Meishan pigs, Myh7 decreased significantly (P<0.01), while Myh4 (P<0.001) and Myh1 (P<0.05) increased significantly.  Meanwhile, the increased expression of Myf5 (P<0.05), Mef2d (P<0.01) and Six1 (P<0.05) in MSTN–/– Meishan pigs suggested that MSTN should regulate the directional development of muscle fiber types in the early stage of embryonic development.  Thus, at the embryonic stage, the type II muscle fibers began to increase in MSTN–/– pigs.  These results can provide valuable information not only for pig meat quality improvement, but also for the study of human skeletal muscle development and disease treatment.    相似文献   

5.
中药复方制剂对奶牛免疫机能的影响   总被引：1，自引：0，他引：1  
选取30头健康奶牛和30头隐性乳房炎奶牛进行中药复方制剂饲喂试验,对奶牛的B淋巴细胞EAC花环形成率、中性粒细胞吞噬率、中性粒细胞吞噬指数和T淋巴细胞转化率进行测定,观察中药复方制剂对奶牛免疫机能的影响.结果显示,健康奶牛的EAC花环形成率、中性粒细胞吞噬率、中性粒细胞吞噬指数、T淋巴细胞转化率均显著高于隐性乳房炎奶牛(P＜0.01或P＜0.05);中药复方制剂可以显著提高健康奶牛和隐性乳房炎奶牛的EAC花环形成率、中性粒细胞吞噬率、中性粒细胞吞噬指数、T淋巴细胞转化率(P＜0.01或P＜0.05).试验表明,中药复方制剂可以增强奶牛机体的体液免疫和细胞免疫功能,促使隐性乳房炎奶牛免疫机能的恢复.  相似文献   

6.
为建立快速并能同时检测无乳链球菌、金黄色葡萄球菌、绿脓杆菌3种奶牛隐性乳房炎致病菌的方法,根据无乳链球菌16S rRNA基因、金黄色葡萄球菌NUC耐热基因、绿脓杆菌ETA基因序列并参考文献各合成一对特异性引物,通过对PCR反应各项参数的调整优化,建立多重PCR检测体系,并同时进行灵敏性试验和特异性试验。结果显示:该检测方法可以同时扩增出无乳链球菌270 bp、金黄色葡萄球菌153 bp和绿脓杆菌375 bp的特异性片段以及细菌16S rRNA 1 500 bp的通用片段,而对于其他的6种病原菌只能扩增出1 500 bp的通用片段,具有较强的特异性。三种特异性引物扩增条带与GenBank上的细菌基因序列同源性为99%。增菌培养24 h,该体系对无乳链球菌、金黄色葡萄球菌、绿脓杆菌的最低灵敏度分别为8×104、4×104、1.5×105 CFU·mL-1。本研究建立的检测方法能够完成无乳链球菌、金黄色葡萄球菌、绿脓杆菌的快速检测,对于生产上奶牛隐性乳房炎的鉴别诊断和快速检测具有重大意义。  相似文献   

7.
哈尔滨地区奶牛隐性乳房炎病原菌的分离鉴定   总被引：3，自引：0，他引：3  
通过BMT法、乳汁pH检验法和体细胞直接计数法等方法相结合,对哈尔滨市3个大型奶牛场、10户奶牛养殖户选取的1 000头奶牛,4000个乳区进行隐性乳房炎的流行病学调查,以及致病菌的分离鉴定.结果表明,其中隐性乳房炎的发病率为47.7%(477/1 000);乳区发病率为27.3%(1092/4000),从477头的隐...  相似文献   

8.
为对引起奶牛乳房炎的病原菌进行溯源,对乳房炎奶牛和正常奶牛的乳头擦拭子和牛奶中细菌的16S rRNA基因的V4-V5高变区进行扩增和高通量测序,使用生物统计学方法分析微生物多样性。结果显示,乳房炎奶牛乳头和牛奶中微生物组成呈现明显差异:在门的水平上,乳头丰度最高的是厚壁菌门(Firmicutes),牛奶则是变形菌门(Proteobacteria),乳头样品均含有拟杆菌门(Bacteroidetes)细菌,而牛奶中几乎没有,梭杆菌门(Fusobacteria)细菌仅存在于乳头中;在属的水平上,梭杆菌属(Fusobacterium)仅在乳头上检测到,牛奶中丰度最高的为假单胞菌属(Pseudomonas)细菌,其仅存在于2个乳头样品中,不动杆菌属(Acinetobacter)细菌在两类样品中都有,但乳头的含量高于牛奶。奶牛患乳房炎后乳头和牛奶的微生物群落与正常奶牛也有差异:梭杆菌门(Fusobacteria)仅在乳房炎奶牛乳头中检测到,正常奶牛没有,乳房炎奶牛乳头金黄色酿脓葡萄球菌属(Staphylococcus)丰度高于正常奶牛,肠球菌属(Enterococcus)仅在乳房炎奶牛牛奶中检测到,正常奶牛没有。奶牛乳头与牛奶中的微生物群落差异极大,奶牛患乳房炎后乳房外和乳房内微生物组成都会发生变化,外源病原菌和内源病原菌都可能引起乳房炎。  相似文献   

9.
奶牛乳腺炎调查及病因分析   总被引：1，自引：0，他引：1  
对佳木斯市4所奶牛场进行流行病学调查,研究临床型乳腺炎和隐性乳腺炎的发病率以及病因。对4所奶牛场的390头泌乳牛进行检测,其中218头患有隐性型乳腺炎,头发病率为55.90%;17头患有临床型乳腺炎,头发病率为4.43%;乳腺炎的头发病率为60.26%。在被检的1416个有效乳区中,患有隐性型乳腺炎的乳区有792个,乳区阳性率为55.93%;患有临床型乳腺炎的乳区有20个,乳区阳性率为1.41%。对牛场圈舍条件和生产、管理诸环节调查分析表明,引起奶牛乳腺炎的主要原因为饲养管理水平较低、饲料品质较低、挤奶工不能严格遵守无菌操作、高产奶牛乳头未开展干奶期预防工作等。  相似文献   

10.
本试验采用杭州乳房炎试验(简称H.M.T.)作为主要诊断指标,改良华沙氏试验(Modified Whiteside test)作为诊断参考指标,对三个奶牛场全部泌乳中期的生产奶牛215头,828个乳区进行隐性型乳房炎普查,并选取检查病变较剧的阳性牛22头,84个乳区,用C.G.N煎剂(栝蒌牛蒡汤加减)离子导入治疗,同时留取检查阳性等级相近的阳性牛22头,83个乳区,不进行治疗处理作为对照。结果表明,治疗组与对照组经Ridit检验,u=6.518,P<0.01,差异极显著。初步证明本疗法对于控制奶牛隐性型乳房炎具有一定疗效,并提示它可能成为早期防治奶牛乳房炎的一种新的有效方法。  相似文献   

11.
为比较热应激与喷淋-风扇系统对热应激期不同泌乳期奶牛生理、生产性能、发病率的影响,将泌乳牛按泌乳时间分为新产牛(0~21 d)、泌乳前期(22~120 d)、泌乳中期(121~200 d)、泌乳后期(201~305 d)奶牛,分别随机选择体况、年龄、泌乳时间相近的健康经产(2~4胎)各泌乳阶段奶牛10头,共计40头作为试验对象。按养殖场日常饲养和管理方式,不做人工干预,热应激期采用喷淋-风扇系统降温。每日测定牛舍温度、相对湿度、风速、直肠温度、呼吸频率、日产奶量、日大缸奶乳成分、日新发肢蹄病、酮病、临床型乳房炎和隐性型乳房炎等。结果表明:喷淋-风扇系统下,热应激期牛舍内温度接近30 ℃,相对湿度为82%,风速达1.35 m·s-1,湿热指数处于中度热应激。热应激期,各泌乳期奶牛直肠温度平均分别升高0.9、0.7、0.6、0.5 ℃,呼吸频率平均分别上升32.9、29.1、29.3、28.5次·min-1,较非热应激期均极显著(P<0.01)升高;新产牛、泌乳前期和中期奶牛日单产均极显著(P<0.01)下降,降幅分别为9.17%、18.97%和13.23%,而泌乳后期奶牛无显著变化(P>0.05),新产牛泌乳启动时奶产量下降,各阶段泌乳牛泌乳峰值均降低;全群泌乳牛乳脂率、脂蛋比均极显著(P<0.01)下降,乳蛋白显著(P<0.05)降低,乳脂率、脂蛋比、乳蛋白含量分别降低0.29百分点、5.23%和1.61%;全群泌乳牛肢蹄病、酮病、临床型乳房炎和隐性型乳房炎发病率分别升高5.77、0.78、2.60和5.77百分点。结果说明:喷淋-风扇系统对舍内热环境改善不显著;热应激影响新产牛和泌乳前期、中期奶牛直肠温度和呼吸频率,使新产牛泌乳启动时产奶量下降,各阶段泌乳牛产奶峰值降低;全群泌乳牛乳品质降低,发病率升高。  相似文献   

12.
Field experiments of nitrogen(N) treatment at five different application rates(0, 75, 150, 225, and 300 kg ha~(-1)) were conducted under pot-seedling mechanical transplanting(PMT) in 2018 and 2019. Two high-quality and high-yielding hybrids of indica rice, Huiliangyou 898 and Y Liangyou 900, were used in this study. The N nutrition index(NNI) and accumulated N deficit(N_(and)), used to assess the N nutrition status in real-time, were calculated for the indica cultivars under PMT with a critical nitrogen concentration(N_c) dilution model based on shoot dry matter(DM) during the whole rice growth stage. The relationships between NNI and N_(and) with relative yield(RY) were determined, and accurate N application schemes were developed for hybrids indica rice under PMT. The results indicated that high application rate of N-fertilizer significantly increased the concentrations of shoot DM and N in aboveground organs during the observed stages in the two cultivars for two years(P0.05). The N_c dilution model of hybrid indica cultivars was N_c=4.02 DM~(-0.42)(R~2=0.97) combining the two cultivars under PMT. Root-mean-square error and normalized root-mean-square error of the curve verification were 0.23 and 10.61%, respectively. The NNI and N_(and) ranged from 0.58 to 1.31 and 109 to –55 kg ha~(-1), respectively, in the two cultivars for all N treatments. NNI showed a linear relationship with N_(and) during the entire growth stage(0.53R~20.99, P0.01). In addition, NNI showed a linear-plateau relationship with RY(0.73R~20.92, P0.01) throughout the observed stages. These results suggest that the models can accurately diagnose the N-nutrition status and support effective N-fertilizer management in real-time for hybrid indica rice under PMT.  相似文献   

13.
采用酿酒酵母(Saccharomyces cerevisiae)和枯草芽孢杆菌(Bacillus subtilis)对棉籽仁进行固态发酵,发酵周期30 h。结果表明,相比发酵前,发酵后棉籽仁中游离棉酚的含量显著(P<0.05)降低,粗灰分、酸溶蛋白质含量显著(P<0.05)增加,精氨酸含量显著(P<0.05)降低。从发酵棉籽仁中提取的棉籽肽具有抗氧化活性,且其活性受使用浓度和发酵时间的影响。当棉籽肽的质量浓度为8 mg·mL-1时,棉籽肽的羟自由基清除率达到(61.71±1.59)%,DPPH自由基清除率为(77.25±1.28)%,金属离子螯合能力达到(79.13±0.55)%。结果提示,在本试验条件下,微生物固态发酵处理可提高棉籽仁的营养品质及其抗氧化活性。  相似文献   

14.
A total of 90 cows from two farms (farm A 30 cows, farm B 60 cows) were used to study the effect of Bospro on milk production, milk quality and subclinical mastitis incidence. The cows in the test group were supplied with 20 g of Bospro per head per day and meanwhile, the percentage of milk fat, protein and lactose and moisture of the milk samples were analysed. The results showed that the milk yield of both high production and mid-to-low milk producting cows increased by 3.3% to 5.3% respectively compared with their control group of cows, but there was no changes on the milk content between the treated and the control cows. The treated cows also showed an increased body weight (P>0.05) and significantly reduced incidence of mastitis, as Compared with that of the control group. The experiment dcmonstrats that Bospro can increase milk yield, but not at the expense of milk quality and body weight.  相似文献   

15.
Trichoderma is an important and widely used plant growth-promoting fungus(PGPF). In this study, stevia residue amended with amino acids hydrolyzed from animal carcasses was used for the production of Trichoderma guizhouense NJAU 4742 by solid-state fermentation, and then its potential to promote corn plant growth was evaluated in combination with chemical fertilizer(CF) or organic fertilizer(OF). The highest spore number of 7×10~9 CFU g~(–1) fresh weight was obtained under the following optimal parameters: material ratio of 50%(stevia residue:rice bran=1:1), pH value of 3.0(amended with 6.67% amino acids), initial moisture content of 60%, inoculum size of 10%, material thickness of 3 cm and an incubation time of 4 days. The aboveground corn plant biomass obtained with T. guizhouense applied alone and with CF treatments were slightly higher than those of no fertilizer control and CF treatments, respectively. However, T. guizhouense applied with OF significantly(P0.05) increased aboveground biomass compared to OF and yielded the highest aboveground biomass among all the treatments. Moreover, T. guizhouense applications primarily influenced the fungal bulk soil community composition, among which three OTUs(OTU_2 and OTU_9 classified as Chaetomium, and OTU_4 classified as Trichoderma) were stimulated in both bulk and rhizosphere soil. Notably, a specific OTU_3(Phymatotrichopsis) was only stimulated by T. guizhouense applied with OF, possibly leading to high soil productivity. These results show that it is feasible to employ stevia residue in the eco-friendly fermentation of T. guizhouense, which is strongly suggested for enhancing OF applications.  相似文献   

16.
Methane (CH4) emissions from ruminant production are a significant source of anthropogenic greenhouse gas production, but few studies have examined the enteric CH4 emissions of lactating dairy cows under different feeding regimes in China.  This study aimed to investigate the influence of different dietary neutral detergent fiber/non-fibrous carbohydrate (NDF/NFC) ratios on production performance, nutrient digestibility, and CH4 emissions for Holstein dairy cows at various stages of lactation. It evaluated the performance of CH4 prediction equations developed using local dietary and milk production variables compared to previously published prediction equations developed in other production regimes.  For this purpose, 36 lactating cows were assigned to one of three treatments with differing dietary NDF/NFC ratios: low (NDF/NFC=1.19), medium (NDF/NFC=1.54), and high (NDF/NFC=1.68).  A modified acid-insoluble ash method was used to determine nutrient digestibility, while the sulfur hexafluoride technique was used to measure enteric CH4 emissions.  The results showed that the dry matter (DM) intake of cows at the early, middle, and late stages of lactation decreased significantly (P<0.01) from 20.9 to 15.4 kg d–1, 15.3 to 11.6 kg d–1, and 16.4 to 15.0 kg d–1, respectively, as dietary NDF/NFC ratios increased.  Across all three treatments, DM and gross energy (GE) digestibility values were the highest (P<0.05) for cows at the middle and late lactation stages.  Daily CH4 emissions increased linearly (P<0.05), from 325.2 to 391.9 kg d–1, 261.0 to 399.8 kg d–1, and 241.8 to 390.6 kg d–1, respectively, as dietary NDF/NFC ratios increased during the early, middle, and late stages of lactation.  CH4 emissions expressed per unit of metabolic body weight, DM intake, NDF intake, or fat-corrected milk yield increased with increasing dietary NDF/NFC ratios.  In addition, CH4 emissions expressed per unit of GE intake increased significantly (P<0.05), from 4.87 to 8.12%, 5.16 to 9.25%, and 5.06 to 8.17% respectively, as dietary NDF/NFC ratios increased during the early, middle, and late lactation stages.  The modelling results showed that the equation using DM intake as the single variable yielded a greater R2 than equations using other dietary or milk production variables.  When data obtained from each lactation stage were combined, DM intake remained a better predictor of CH4 emissions (R2=0.786, P=0.026) than any other variables tested.  Compared to the prediction equations developed herein, previously published equations had a greater root mean square prediction error, reflecting their inability to predict CH4 emissions for Chinese Holstein dairy cows accurately.  The quantification of CH4 production by lactating dairy cows under Chinese production systems and the development of associated prediction equations will help  establish regional or national CH4 inventories and improve mitigation approaches to dairy production.  相似文献   

17.
奶牛隐性乳房炎发生规律的研究   总被引：1，自引：0，他引：1  
对433头泌乳奶牛隐性乳房炎发病规律进行了调查研究。发现该牧场奶牛隐性乳房炎发病率为29.33%,乳区阳性率为33.60%。病原菌的总检出率为91.67%,引起隐性乳房炎发生的致病菌主要为金黄色葡萄球菌和大肠杆菌,分别占总检出率的37.88%和16.67%。同时对发病率与乳区、年龄、胎次及日均产奶量等的关系进行了相关分析。结果表明,各乳区间发病率差异不显著;隐性乳房炎的发病率随着奶牛年龄的增加而有所上升(P<0.01);不同胎次组间发病率差异显著(P<0.05);日均产奶量20 kg以下的牛群发病率极显著高于日均产奶量20 kg以上的牛群(P<0.01)。  相似文献   

18.
采用盆栽实验研究不同NaCl添加量(质量分数分别为0、0.1%、0.2%、0.3%和0.4%)对红叶石楠地上部鲜重、株高、叶片Na含量、K+/Na+、细胞膜透性、叶片含水量、脯氨酸含量、抗氧化酶活性,以及花青素含量的影响。结果表明,在0.2%及更高浓度的NaCl处理下,红叶石楠生长受到抑制,叶片Na含量、细胞膜透性、脯氨酸含量显著(P<0.05)增加,K+/Na+、叶片相对含水量显著(P<0.05)下降。盐胁迫造成红叶石楠叶片的H2O2及丙二醛(MDA)含量显著(P<0.05)增加,0.4%NaCl处理下,H2O2及MDA含量在新叶上的增幅分别为162%和128%,在老叶上的增幅分别为114%和33%。随着盐胁迫加剧,新叶氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性显著(P<0.05)升高,过氧化物酶(POD)活性和花青素含量显著(P<0.05)下降。与之相反,老叶的SOD和CAT酶活显著(P<0.05)下降,而POD活性和花青素含量显著(P<0.05)上升。由此可见,花青素在抵御盐胁迫诱导的氧化伤害中具有重要作用,其在叶片中的含量与CAT酶活性呈现此消彼长的关系。  相似文献   

19.
试验旨在研究饲粮添加乳双歧杆菌对蛋雏鸡盲肠微生物多样性的影响。选取1日龄健康、体质量相近的罗曼褐蛋公雏216只,随机分成2个处理组,每组6个重复,每个重复18只鸡,对照组饲喂基础饲粮(C组),试验组饲喂基础饲粮另添加乳双歧杆菌制剂(T组,添加量:1×107 cfu·g-1),试验期42 d。试验结束后,每个处理组随机选取6只鸡,再从中选出体质量相近且状态良好的3只,收集盲肠食糜样,并应用Illumina MiSeq高通量测序技术分析盲肠微生物多样性。结果表明:(1)乳双歧杆菌可显著提高雏鸡体质量、平均日增重及平均日采食量(P<0.05)。(2)两组间优势菌门均为拟杆菌门(Bacteroidetes)、厚壁菌门(Firmicutes)和变形菌门(Proteobacteria),试验组Firmicutes和Bacteroidetes数量的比值高于对照组。(3)乳双歧杆菌可显著提高Barnesiella、Romboutsia、Butyricicoccus、Lactobacillus等有益菌含量,而显著降低Clostridium sensu stricto、Escherichia-Shigella的含量(P<0.05)。(4)乳双歧杆菌可提高盲肠菌群丰度,显著提高Shannon和Simpson指数(P<0.05)。综上,饲粮添加乳双歧杆菌后,可能通过改变盲肠微生物的组成结构和含量来发挥益生作用。  相似文献   

20.
通过传统分离鉴定技术调查上海地区某奶牛场隐性乳房炎奶样真菌感染情况,并利用DGGE技术对真菌群落结构进行分析,研究真菌在隐性乳房炎奶样中的分布情况.结果表明,隐性乳房炎奶样病原菌阳性率为90.80％,其中混合感染率为22.78％,霉菌感染率8.05％,酵母菌感染率2.30％.对真菌感染奶样中真菌群落结构的分析显示,病原真菌包括曲霉属、酵母菌以及青霉属3大类,每份奶样含有2～8种真菌不等,烟曲霉、黑曲霉和斜卧青霉普遍存在.  相似文献   

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