人参皂苷和多糖对肺肠功能影响研究进展

消化和呼吸功能是畜牧养殖过程中面临的两大问题,其会严重影响畜牧业经济效益。作为人参主要功能性成分,人参总皂苷和人参多糖在肺肠功能调节方面具有较好效果。本文总结了近年来人参总皂苷和人参多糖对肺肠功能调节的研究情况,以期为其在畜牧生产应用方面提供参考。     

Bamboo NiR gene is associated with regeneration capacity

It was reported that the activity of NiR (nitrite reductase) enzyme encoded by the NiR gene was correlated with the regeneration ability in rice. To testify the function of NiR gene in bamboo, seven bamboo species whose calli had different differentiation rate were chosen to analyse their NiR enzyme activity. The results showed that bamboo NiR enzymatic activity had a certain correlation with the regeneration capacity. A NiR gene named DhNiR from Dendrocalamus hamiltonii with high regeneration capacity was cloned. Sequence analysis revealed that the ORF of DhNiR was 1779bp encoding 592 amino acids. Overexpression of DhNiR in rice reduced the time of shoot differentiation and increased the transformation rate, suggesting that DhNiR might play an important role in the regeneration ability of bamboo, and can be applied in regeneration and gene transformation of bamboo and other plant species.     

干湿交替灌溉对抗旱性不同水稻品种产量的影响及其生理原因分析

【目的】旨在阐明全生育期干湿交替灌溉对抗旱性不同水稻品种产量的影响。【方法】以抗旱性差异显著的4个水稻品种(籼稻扬稻6号和两优培九,粳稻旱优8号和镇稻88)为材料,以常规水层灌溉(CI)为对照,在盆栽条件下研究了轻干湿交替灌溉(WMD)和重干湿交替灌溉(WSD)对水稻产量、根系、叶片及籽粒部分生理特性的影响。【结果】与CI相比,WMD处理下抗旱性较强品种扬稻6号和旱优8号产量分别提高6.90%和7.45%,抗旱性较弱品种两优培九和镇稻88产量分别降低7.28%和8.10%。WSD处理下,4个水稻品种的产量均显著下降,抗旱性较弱的品种产量降幅远高于抗旱性较强的水稻品种。WMD处理下,扬稻6号和旱优8号复水后根系氧化力、根系与叶片细胞分裂素(玉米素+玉米素核苷)含量、叶片光合速率和籽粒中蔗糖-淀粉代谢途径关键酶的活性均较CI有不同程度提高,而两优培九和镇稻88上述指标则与CI持平或有不同程度降低。WSD处理下,4个品种上述指标均较CI不同程度降低。【结论】轻干湿交替灌溉条件下,根系活性强、叶片细胞分裂素含量和光合速率高、籽粒中蔗糖-淀粉代谢途径关键酶活性强是抗旱性较强水稻品种的基本生理特征。     

Effect of cortisol and triiodothyronine bath treatments on the digestive enzyme profile and growth of Catla catla larvae during ontogenic development

Digestive enzyme profile is a good indicator of the nutritional and health status of the fish. The present investigation aims to evaluate the effect of exogenous bath treatment of hormones, cortisol and triiodothyronine, on the digestive enzyme activities and growth of carp Catla catla (Ham.) during ontogenic development. Catla larvae (4 days old) were given bath treatment with cortisol (hydrocortisone, 0.2 mg L^?1), 3,5,3′‐triiodothyronine (T3, 2.5 mg L^?1) and a combination of cortisol and T3 for 30 min. Digestive enzyme profile was recorded on every third day and was continued for 30 days. Larvae were fed with live food for initial 14 days and then weaned to mix feeding of live food and prepared diet. Significantly (P < 0.05) higher amylase, total protease, trypsin, chymotrypsin, lipase, chitinase and chitinobiase activities were found in the hormone‐treated groups compared to the control one during ontogenic development. Among the treated groups, amylase activity was highest in cortisol‐treated larvae. Total protease, trypsin, chymotrypsin, lipase, chitinase and chitinobiase activities were significantly (P < 0.05) higher in larvae exposed at combined treatment of cortisol and T3 compared to the other two groups in most sampling days. Average length, weight and specific growth rate of treated larvae were higher compared to the control one. The combined bath treatment of cortisol and triiodothyronine influenced the digestive enzyme activities of catla larvae and thereby enhanced the growth at early developmental stage. This helps the larvae to overcome the problems associated with early developmental stage.     

Effects of dietary protein to energy ratios on growth,body composition and digestive enzyme activities in Chinese mitten‐handed crab,Eriocheir sinensis

This study aimed to determine the optimal protein to energy ratio (P/E ratio) and evaluate the effect of dietary protein and lipid levels on growth performance, body composition and digestive enzymes activities in Chinese mitten‐handed crab, Eriocheir sinensis. Nine practical diets containing three levels both for protein (DP 30%, 35% and 40%) and lipid (DL 2%, 7% and 12%) with P/E ratios ranging from 13.69 to 19.79 mg KJ^?1 were fed to four replicates of crabs (3.39 ± 0.10 g) for 10 weeks. Weight gain increased significantly with the increase in DP level at each DL level. Moreover, weight gain increased in crabs fed with diets containing DL level from 2% to 12% and DP level from 30% to 35%. However, the diet containing 40% DP and 12% DL levels significantly decreased the growth performance and protein efficiency of the crabs. The whole crab and hepatopancreas lipid contents also increased as dietary lipid increased, but not dietary protein. The total protease activity increased significantly with the increase in dietary protein at each lipid level. The lipase activity was statistically comparable among different DL levels at each DP level. Taken together, the crab fed the diet containing 35% protein and 12% lipid levels with P/E 15.77 mg KJ^?1 revealed optimal growth, feed utilization efficiency and digestive enzymes activities. Moreover, our study indicated that the higher dietary lipid level at a relatively lower dietary protein level could provide protein sparing effect in Eriocheir sinensis.     

温度对波纹龙虾消化酶活力的影响

研究了波纹龙虾温度对不同消化器官中消化酶活力的影响,为人工饲料科学配制依据。用酶学分析方法,设计6个温度梯度(20℃、25℃、30℃、35℃、40℃和45℃),分别测定波纹龙虾胃、肠和肝胰脏的类胃蛋白酶、胰蛋白酶、淀粉酶和脂肪酶的活力。结果显示:在反应温度20℃~45℃范围内,波纹龙虾胃、肠、肝胰脏内的消化酶均随着温度的升高表现为先升后降趋势;不同消化器官中胃蛋白酶活力值出现拐点的温度不一样,胃、肠和肝胰脏的胃蛋白酶活力最大的温度分别是30℃、35℃和40℃;不同消化器官胃蛋白酶的活力有显著差异(P0.05),大小依次为胃肠肝胰脏;波纹龙虾不同消化器官的类胰蛋白酶出现最大酶活力的温度相同,为40℃,但胃的类胰蛋白酶活力明显较肠和肝胰脏的低(P0.05),差值最大可达40 U/mg;波纹龙虾胃、肠和肝胰脏的淀粉酶活力在25℃均出现最大值;在消化器官中,肠道淀粉酶活力最大,与胃和肝胰脏的酶活力有显著性差异(P0.05);波纹龙虾胃、肠和肝胰脏内的脂肪酶活力最大的温度为30℃,活力最高的是肝胰脏,胃内的脂肪酶活力明显的比肠和肝胰脏的要低(P0.05)。     

Characterization of Collagen Enzymatic Hydrolysates Derived from Lizardfish (Synodus fuscus) Scales

Acid soluble collagen was extracted from the scales of lizardfish and characterized with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and amino acid analysis. After 8 h of collagen hydrolysis, hydrolysates had an estimated degree of hydrolysis (DH) from 4 ± 0.05 to 25 ± 0.63% (p < 0.05). All hydrolysates had angiotensin converting enzyme inhibitory and antioxidant activity. These activity levels showed little change after treatment with gastrointestinal proteases. Results indicated that the lizardfish by-products may be improved by enzymatic treatment with acid-soluble collagen from lizardfish scales.     

裸果木渗透调节物质和抗氧化酶活性对干旱的响应

裸果木(Gymnocarpos przewalskii)起源于古地中海,为荒漠区少有的第三纪孑遗植物种。本文采用2017年6月、7月和8月采集于甘肃安西自然保护区内的裸果木中龄和老龄植株叶片,分析自然干旱影响下叶片渗透调节物质及抗氧化酶活性的变化。结果表明:随着干旱程度的增加,裸果木叶片的可溶性蛋白(SP)显著积累,发挥着重要的渗透调节作用,中龄植株叶片的可溶性糖(SS)含量和老龄植株叶片的脯氨酸(Pro)含量先增加后显著降低,渗透调节作用有限。干旱加剧时,中龄植株叶片的超氧化物歧化酶(SOD)活性和抗坏血酸过氧化物酶(APX)活性呈明显的先增后降。严重干旱时,过氧化物酶(POD)活性和过氧化氢酶(CAT)活性明显增强,说明其通过4种酶的协同作用清除过剩的活性氧,减轻过氧化伤害;老龄植株叶片的CAT活性持续增强,APX活性明显的先升后降,POD活性在重度干旱时显著增强,主要通过这3种酶减轻膜系统伤害。丙二醛(MDA)含量则随干旱程度增大显著增加,膜脂过氧化程度不断加深。在相同的降雨条件下,裸果木中、老龄植株的Pro、SS、SP含量、POD和CAT活性、MDA含量对干旱的响应程度存在显著差异,隶属度函数评价法表明,老龄植株的抗旱能力大于中龄植株,表明裸果木的抗旱性随年龄的增大而提高。     

有机肥对酿酒葡萄土壤微生物、酶活性及产量的影响

为明确施用不同有机肥对土壤有机质、酶活性和微生物以及酿酒葡萄产量的影响,采用田间小区设计,以5 a生赤霞珠酿酒葡萄为试验材料,研究不同有机肥对土层0～20、20～40 cm和40～60 cm中土壤有机质、酶活性和微生物的影响。以不施用有机肥为对照(CK),设置沼渣(BR)、羊粪有机肥(SMOF)、牛粪有机肥(CMOF)、猪粪有机肥(PMOF)、牛粪+沼渣有机肥(CMOF+BR)5个处理进行大田试验。结果表明:不同有机肥施用后与CK相比,土壤有机质增加6.79%～44.97%,土壤微生物碳增加19.78%～91.53%,微生物氮增加2.22倍～3.93倍,碱性磷酸酶增加57.78%～512.55%,过氧化氢酶增加53.45%～240.48%,增产15.12%～46.89%。不同土层施用牛粪有机肥相对于其它有机肥处理土壤有机质含量增长8.49%～33.29%;土壤中微生物碳、氮的含量分别增加5.30%～42.46%和6.12%～49.65%;碱性磷酸酶增大8.01%～184.63%,过氧化氢酶增加5.14%～84.27%,脲酶提高25.58%～410.70%,蔗糖酶升高6.00%～107.65%;微生物总数增多5.99%～56.56%。施用牛粪有机肥相比较其它有机肥增产7.08%～27.60%。说明在宁夏地区施用有机肥可有效提高土壤有机质的含量,增加微生物的数量,增加土壤酶活性,促进酿酒葡萄的生长发育,提高产量,其中以牛粪效果最为显著。     

Effect of transferring lignocellulose-degrading bacteria from termite to rumen fluid of sheep on in vitro gas production,fermentation parameters,microbial populations and enzyme activity

The digestive tract of termite(Microcerotermes diversus) contains a variety of lignocellulose-degrading bacteria with exocellulases enzyme activity, not found in the rumen, which could potentially improve fiber degradation in the rumen. The objectives of the current study were to determine the effect of inoculation of rumen fluid(RF) with three species of bacteria isolated from termite digestive tract, Bacillus licheniformis, Ochrobactrum intermedium, and Microbacterium paludicola, on in vitro gas production(IVGP), fermentation parameters, nutrient disappearance, microbial populations, and hydrolytic enzyme activities with fibrous wheat straw(WS) and date leaf(DL) as incubation substrate. Inoculation of RF with either of three termite bacteria increased(P0.05) ammonia-N concentration compared with the control group(free of termite gut bacteria). Termite bacteria inoculation had no effect(P0.05) on gas production characteristics, dry matter, organic matter and neutral detergent fiber disappearance, pH, and concentration and composition of volatile fatty acids. Population of proteolytic bacteria and protozoa, but not cellulolytic bacteria, were increased(P0.05) when RF was inoculated with termite bacteria with both WS and DL substrates. Inoculation of RF with termite bacteria increased protease activity, while activities of carboxymethyl-cellulase, microcrystalline-cellulase, α-amylase and filter paper degrading activity remained unchanged(P0.05). Overall, the results of this study indicated that transferring lignocellulose-degrading bacteria, isolated from digestive tract of termite, to rumen liquid increased protozoa and proteolytic bacteria population and consequently increased protease activity and ammonia-N concentration in vitro, however, no effect on fermentation and fiber degradation parameters were detected. These results suggest that the termite bacteria might be rapidly lysed by the rumen microbes before beneficial effects on the rumen fermentation process could occur.