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1.
Spirulina has been used as human food supplement for over 20 years, but its use as an animal feed supplement is relatively recent. This paper reviews earlier studies on its more established effects on growth, survival and tissue quality in a whole range of animals and more recent studies on its immunomodulatory, anti-viral and anti-cancer effects. The basis for potential application as an animal feed supplement is discussed.  相似文献   

2.
Aims:  To evaluate disinfectants against Salmonella under conditions relevant for the feed industry.
Materials and Results:  A survey on the use of disinfectants in feed industry showed that a range of different types was used. Nine disinfectants, reflecting the most commonly used active ingredients, were tested for bactericidal activity on Salmonella isolated from the feed industry. All disinfectants were efficient against Salmonella in suspension. The bactericidal effect varied considerably between different types of active compounds on bacteria dried on surfaces or grown as biofilm. Tenside-based disinfectants and hypochlorite were found to have low bactericidal activity and the efficiency was significantly reduced when the ratio of amount disinfectant per cell decreased. It was shown that concentrations of 70–80% ethanol were effective against Salmonella. Among the disinfectants tested a product containing 70% ethanol was most efficient followed by Virkon S.
Conclusions:  Many disinfectants had low bactericidal activity against Salmonella at surfaces while Virkon S and a product containing 70% ethanol were most effective. Another advantage of ethanol-based disinfectants is evaporation of ethanol, resulting in low residual water after use.
Significance and Impact of the Study:  Use of the disinfectants found to be efficient against surface associated Salmonella , may assist the industry in combating Salmonella .  相似文献   

3.
4.
The anaerobic digestion technology is a biological treatment widely used to reduce the pollution load of wet waste biomass. In this work we present the results obtained by performing extensive experiments of anaerobic digestion of slaughterhouse waste, tomato industry waste and olive oil industry waste in continuous mode, which were designed to demonstrate that anaerobic digestion is an effective technology from an environmental and economic point of view.Biogas yields obtained are between 35.22 and 5.45 Nm3 biogas/m3 olive oil industry waste and tomato industry waste respectively and the slaughterhouse wastes achieve intermediate production, 30.86 Nm3 biogas/m3 municipal slaughterhouse waste and 22.53 Nm3 biogas/m3 Iberian pig slaughterhouse waste. Moreover, it possible to degrade between 63.46 and 75.3% of the initial organic matter.If these results are analyzed, the environmental, energetic economic benefits of anaerobic digestion can be quantified. Biomethanation of all these wastes generated annually in Extremadura could prevent the emission of 134,772 t of equivalent carbon dioxide, generate an energy similar to that provided by 2826 toe and reach payback times from 3.29 to 3.75 years for anaerobic digestion plant designed to treat the wastes generated by a medium-sized industry. So, we have fulfilled all the planned aims.  相似文献   

5.
Osseointegration of implant provides a stable support for the prosthesis under functional loads. The timing of loading is a critical parameter that can govern the success of the osseointegration of implant. However, it is not clear whether the early loading can affect the success of osseointegration, or whether the no-loading healing period can be shortened. This paper presents an animal study conducted to investigate how external loads influence the osseointegration at the initial stage of healing. Titanium implants were inserted into the goat tibia laterally, and different axial loadings were applied to the implants in 4 weeks after surgery. After the 2 weeks period of early loading, animals were sacrificed and the tibia bones with the implants were cut off from the bodies. Then mechanical test was employed to find out the differences in the pull-out force, and shear strength at the bone-implant interface between the non-loaded and the loaded implants. The implant-bone interfaces were analyzed by histomorphometric method, SEM (scanning electron micrograph) and EDS (energy density spectrum). The results indicated that the bone-implant interface did not well integrate 4 weeks after surgery, and the fibrous tissue could be found at the interfaces of the specimens without loadings. While the results of loaded specimens with 10 N axial force showed that that parts of the interface were well integrated, indicating that the early mild loading may play a positive role in the process of the osseointegration. The results support that a certain range of external loading would influence the process of osseointegration, and appropriate mechanical loading can be applied to shorten the osseointegration period after surgery. Supported by the National Natural Science Foundation of China (Grant Nos. 30370376, 10529202 and 10672015).  相似文献   

6.
This investigation deals with the use of agro-industrial waste, namely groundnut oil cake (GOC), for phytase production by the fungi Aspergillus niger NCIM 563. Plackett–Burman design (PBD) was used to evaluate the effect of 11 process variables and studies here showed that phytase production was significantly influenced by glucose, dextrin, distilled water, and MgSO4 · 7H2O. The use of response surface methodology (RSM) by Box–Behnken design (BBD) of experiments further enhanced the production by a remarkable 36.67-fold from the original finding of 15 IU/gds (grams of dry substrate) to 550 IU/gds. This is the highest solid-state fermentation (SSF) phytase production reported when compared to other microorganisms and in fact betters the best known by a factor of 2. Experiments carried out using dried fermented koji for phosphorus and mineral release and also thermal stability have shown the phytase to be as efficient as the liquid enzyme extract. Also, the enzyme, while exhibiting optimal activity under acidic conditions, was found to have significant activity in a broad range of pH values (1.5–6.5). The studies suggest the suitability of the koji supplemented with phytase produced in an SSF process by the “generally regarded as safe” (GRAS) microorganism A. niger as a cost-effective value-added livestock feed when compared to that obtained by submerged fermentation (SmF).  相似文献   

7.
周伟  钟祥浩 《生态学杂志》2006,25(7):800-804
自然保护区内的野生动物大量进入承包草场后,因与家畜争食并破坏草场,和牧民的冲突日益严重,需要制定相应的管理方案加以控制。在藏北高原的羌塘自然保护区与承包草场的边界选取了观察区域,通过样线调查和PRA方法,并选用优势-劣势-机遇-风险分析矩阵评估了现有的管理能力、牧民态度、当地知识体系、当地提出的管理方案与提议等。结果表明,在牧场超载、退化严重的状况下,野生动物与家畜争食使得草场使用的控制目标难以实现;放任自流和修建隔离墙等方案均不可取;自然保护区外野生动物保护是一个循序渐变过程,可根据牧民收入水平、对野生动物的容忍度、当地财政收入状况,充分利用当地知识体系,以成本-效益原则为基础,来制定相应的管理措施;积极吸纳牧民参与管理,尽快实践社区共管的自然保护区外野生动物的管理模式。  相似文献   

8.
Although numerous studies have been carried out to investigate the water footprint of different economies at global, national and regional scales, the research on water footprint of individual economic sector, which is the elementary part of each economy, is still lacking. To fill the gap, this paper for the first time employs a hybrid method to evaluate the water footprint of gaming industry in water scarce Macao, based on the latest statistics and most exhaustive embodied water intensity databases. The results show that direct water use only accounts for extremely small fraction of the gaming industry's water footprint, indicating that the exchange of water embodied in product and service between different sectors is also a useful mean to satisfy individual sector's demand for water resources. As Macao's demand for water is growing, integrated plans including economic instruments and measures like reducing the scale of commission input and promoting efficiency would ease Macao's water pressure. Water footprint assessment in this study brings along new perspectives on gaming industry's water management and encourages wise use of goods, materials and services in a sustainable way.  相似文献   

9.
The effect of certain simple and cost-effective processing methods on the nutritional and anti-nutritional properties of seed materials of an under-utilized food legume, Mucuna pruriens (L.) DC. var. utilis (Wall. ex Wight) Baker ex Burck (velvet bean, VB), collected from Valanadu, Kerala, India was analyzed in experiment 1. The raw VB seeds were found to contain appreciable levels of crude protein (263.2 g/kg dry matter (DM)); ether extract (79.6 g/kg DM); crude fiber (95.8 g/kg DM) and ash content (38.4 g/kg DM). Among the different treatments used, soaking in sodium bicarbonate solution + autoclaving was more effective in reducing maximum levels of various anti-nutritional compounds of VB seeds. Furthermore, in experiment 2, the effect of inclusion of different levels of velvet bean meal (VBM; subjected to soaking in sodium bicarbonate solution + autoclaving) as an alternative protein source in poultry feed on the growth performance of commercial-type broiler birds was investigated. The results indicate that the inclusion of VBM up to the 40% level exhibited better growth performance of the broiler birds such as feed intake, body weight gain, feed conversion ratio and protein efficiency ratio in both the starter and finisher phases.  相似文献   

10.
城市餐饮业食物浪费碳足迹——以北京市为例   总被引:6,自引:0,他引:6  
食物浪费及其造成的环境影响已成为全球广泛关注的热点。无论从生命周期还是碳足迹的视角来看,食物浪费意味着生产、运输、加工与储存这些被浪费掉的食物过程中所投入的各种资源的浪费以及不必要的温室气体排放。以北京市餐饮食物浪费问题为切入点,在通过问卷调查和称重方法对餐饮食物浪费状况进行调查的基础上,将整个食物生命周期各供应链环节相应的温室气体排放纳入考量,估算了北京市餐饮食物浪费的碳排放量。研究结果表明:北京市餐饮食物浪费总量为39.86×10~4t/a。其中,蔬菜类浪费量最高,约占浪费总量的43.16%,其次为肉类和主食类,分别占食物浪费总量的20.59%和16.66%。北京市餐饮食物浪费所产生的总碳足迹为192.51×10~4—208.52×10~4t CO_2eq。其中,农业生产阶段的碳排放量最大为99.34×10~4t CO2eq,占食物浪费总碳足迹的47.64%。其次是消费阶段的碳足迹77.96×10~4t CO_2eq,占食物浪费总碳足迹的37.39%,再次是餐厨垃圾处理阶段的碳足迹28.54×104tCO2eq,占食物浪费总碳足迹的13.68%。这些不同供应链环节的碳排放比例,为透视食物浪费所带来的环境影响提供了新的认知,也为遏制食物浪费提供了科学的理论依据。  相似文献   

11.
We report evidence of one of the oldest known animal migratory episodes in the form of queues of the eyeless trilobite Trimerocephalus chopini Kin & B?a?ejowski, from the Late Devonian (Famennian) of central Poland. In addition, there is evidence for two morphs in this population, one with nine segments and the other with ten. We infer that these queues represent mass migratory chains coordinated by chemotaxis, comparable to those observed in modern crustaceans such as spiny lobsters, and further suggest that the two forms, which occur in an approximately 1:1 ratio, may be dimorphs. These ancient arthropods may have migrated periodically to shallow marine areas for mass mating and spawning. The sudden death of the trilobites in the queues may have been caused by excess carbon dioxide and hydrogen sulphide introduced into the bottom water by distal storm disturbance of anoxic sediments. This study demonstrates the potential for further research on the evolution and ecology of aggregative behaviour in marine arthropods.  相似文献   

12.
The food-feed competition is one of the complex challenges, and so are the ongoing climate change, land degradation and water shortage for realizing sustainable food production systems. By 2050 the global demand for animal products is projected to increase by 60% to 70%, and developing countries will have a lion’s share in this increase. Currently, ~800 million tonnes of cereals (one-third of total cereal production) are used in animal feed and by 2050 it is projected to be over 1.1 billion tonnes. Most of the increase in feed demand will be in developing countries, which already face many food security challenges. Additional feed required for the projected increased demand of animal products, if met through food grains, will further exacerbate the food insecurity in these countries. Furthermore, globally, the production, processing and transport of feed account for 45% of the greenhouse gas emissions from the livestock sector. This paper presents approaches for addressing these challenges in quest for making livestock sector more sustainable. The use of novel human-inedible feed resources such as insect meals, leaf meals, protein isolates, single cell protein produced using waste streams, protein hydrolysates, spineless cactus, algae, co-products of the biofuel industry, food wastes among others, has enormous prospects. Efficient use of grasslands also offers possibilities for increasing carbon sequestration, land reclamation and livestock productivity. Opportunities also exist for decreasing feed wastages by simple and well proven practices such as use of appropriate troughs, increase in efficiency of harvesting crop residues and their conversion to complete feeds especially in the form of densified feed blocks or pellets, feeding as per the nutrient requirements, among others. Available evidence have been presented to substantiate arguments that: (a) for successful and sustained adoption of a feed technology, participation of the private sector and a sound business plan are required, (b) for sustainability of the livestock production systems, it is also important to consider the consumption of animal products and a case has been presented to assess future needs of animal source foods based on their requirements for healthy living, (c) for dairy animals, calculation of Emission Intensity based on the lifetime lactation rather than one lactation may also be considered and (d) for assessment of the efficiency of livestock production systems a holistic approach is required that takes into consideration social dimensions and net human-edible protein output from the system in addition to carbon and water footprints.  相似文献   

13.
ABSTRACT

Soil fungi were studied in three desert areas in Namibia with the aim of identifying saprotrophic microorganisms associated with animal communities as opportunistic pathogens. The extremely arid environment of the Naukluft Desert Park was found to be more selective for soil fungi, whereas the soils of Etosha Pan, with seasonal wet areas, and the mobile dunes of Sossousvlei, which absorb atmospheric moisture at night by virtue of their proximity to the sea, host saprotrophic microorganisms and potential and/or opportunistic pathogens.  相似文献   

14.
AIMS: To investigate whether treatment of animals feeds with organic acids/formaldehyde may mask the presence of Salmonella, when assessed by standard cultural methods. METHODS AND RESULTS: Four commercial treatments were applied at the manufacturers' recommended rates on feeds artificially inoculated with Salmonella. The recovery of Salmonella from these treated feeds was assessed after specific antagonists were added to the treatments during culture. A control group of treated feed received no antagonist. Masking of Salmonella was demonstrated when the addition of antagonists resulted in recovery of Salmonella from the treated feed, compared with a negative recovery when no antagonists were added. There were large variations in the efficacy of treatments, and masking was demonstrated with all four tested treatments. One formaldehyde-based product showed greater efficacy and less masking. Masking was greater when high levels of Salmonella were present in the feed. CONCLUSIONS: Some organic acid or formaldehyde-based feed treatments may mask the presence of Salmonella. SIGNIFICANCE AND IMPACT OF THE STUDY: Feeds may be deemed safe despite being contaminated with Salmonella. The use of antagonists during culture may help assess the level of Salmonella contamination when organic acid or formaldehyde treatments have been applied to feed ingredients.  相似文献   

15.
高梅香  朱家祺  刘爽  程鑫  刘冬  李彦胜 《生态学报》2023,43(16):6862-6877
土壤动物学面临以全新知识体系为科学研究框架的变革时期,其核心内容是以数据驱动为主要特征的人工智能技术方法。目前广泛应用的基于数据库的数据处理分析方法,面临着数据多源异构、快速增长和处理能力不足之间的矛盾。基于快速发展的大数据科学和人工智能技术的数据挖掘方法在解决前述矛盾中有突出优势,但需要依赖一个强大的领域知识库,然而土壤动物领域知识图谱的研究十分匮乏。土壤动物知识图谱是一个具有有向图结构的知识库,其中图的节点代表与土壤动物相关的实体或概念,图的边代表实体或概念之间的各种语义关系。提出了土壤动物知识图谱的定义、内涵、理论模型和构建方法,以浙江天目山土壤螨类多样性为例,分析了构建山地土壤动物知识图谱的技术方法;以土壤动物多样性研究关注的物种分布、物种共存、环境条件对物种的影响作用为例,探讨了基于山地土壤动物知识图谱可以解决的相关科学问题。研究表明,土壤动物知识图谱在解决生物多样性重要科学问题方面具有独特的潜力和优势,有力推动了土壤动物学、信息科学和数据科学交叉的土壤动物信息学的发展。  相似文献   

16.
In response to increasing efforts for reducing concentrate inputs to organic dairy production in grassland-rich areas of Europe, a long-term study was conducted, which assessed the impacts of concentrate reductions on cows’ performance, health, fertility and average herd age. In total, 42 Swiss commercial organic dairy cattle farms were monitored over 6 years (‘Y0’, 2008/09 until ‘Y5’, 2013/14). In comparison with overall data of Swiss herdbooks (including conventional and organic farms), the herds involved in the project had lower milk yields, similar milk solids, shorter calving intervals and higher average lactation numbers. During the first 3 project years farmers reduced the concentrate proportion (i.e. cereals, oilseeds and grain legumes) in the dairy cows’ diets to varying degrees. In Y0, farms fed between 0% and 6% (dietary dry matter proportion per year) of concentrates. During the course of the study they changed the quantity of concentrates to voluntarily chosen degrees. Retrospectively, farms were clustered into five farm groups: Group ‘0-conc’ (n=6 farms) already fed zero concentrates in Y0 and stayed at this level. Group ‘Dec-to0’ (n=11) reduced concentrates to 0 during the project period. Groups ‘Dec-strong’ (n=8) and ‘Dec-slight’ (n=12) decreased concentrate amounts by >50% and <50%, respectively. Group ‘Const-conc’ (n=5 farms) remained at the initial level of concentrates during the project. Milk recording data were summarised and analysed per farm and project year. Lactation number and calving intervals were obtained from the databases of the Swiss breeders’ associations. Dietary concentrate amounts and records of veterinary treatments were obtained from the obligatory farm documentations. Data were analysed with GLMs. Daily milk yields differed significantly between farm groups already in Y0, being lowest in groups 0-conc (16.0 kg) and Dec-to0 (16.7 kg), and highest in groups Dec-slight (19.6 kg) and Const-conc (19.2 kg). Milk yield decreases across the years within groups were not significant, but urea contents in milk decreased significantly during the course of the project. Milk protein, somatic cell score, fat–protein ratio, average lactation number, calving interval and frequency of veterinary treatments did not differ by group and year. In conclusion, 5 years of concentrate reduction in low-input Swiss organic dairy farms, affected neither milk composition, nor fertility and veterinary treatments. Milk yields tended to decline, but at a low rate per saved kilogram of concentrate.  相似文献   

17.
Even though Helicobacter pylori infection was the most causative factor of gastric cancer, numerous in vivo studies failed to induce gastric cancer using Hpylori infection only. The utilization of established animal studies in cancer research is crucial as they aim to investigate the coincidental association between suspected oncogenes and pathogenesis as well as generate models for the development and testing of potential treatments. The methods to establish gastric cancer using infected animal models remain limited, diverse in methods, and showed different results. This study investigates the differences in animal models, which highlight different pathological results in gaster by literature research. Electronic databases searched were performed in PubMed, Science Direct, and Cochrane, without a period filter. A total of 135 articles were used in this study after a full-text assessment was conducted. The most frequent animal models used for gastric cancer were Mice, while Mongolian gerbils and Transgenic mice were the most susceptible model for gastric cancer associated with Hpylori infection. Additionally, transgenic mice showed that the susceptibility to gastric cancer progression was due to genetic and epigenetic factors. These studies showed that in Mongolian gerbil models, Hpylori could function as a single agent to trigger stomach cancer. However, most gastric cancer susceptibilities were not solely relying on Hpylori infection, and numerous factors are involved in cancer progression. Further study using Mongolian gerbils and Transgenic mice is crucial to conduct and establish the best models for gastric cancer associated Hpylori.  相似文献   

18.
Mizrahi A  Lazar A 《Cytotechnology》1988,1(3):199-214
The increasing interest in products from animal cells has caused an extensive research effort towards development of media for cell cultivation.The basic components in the media used for cultivation of animal cells vary depending upon the characters of the cells and the cultivation method. Basic components consist of an energy source, nitrogen source, vitamins, fats and fatty soluble components, inorganic salts, nucleic acid precursors, antibiotics, oxygen, pH buffering systems, hormones, growth factors and serum. Extensive efforts are directed towards developing serum-free or chemically defined media. Among the serum substitutes is a long list of hormones and growth factors.  相似文献   

19.
刘军  岳梦婷  问鼎 《生态学报》2023,43(15):6212-6224
旅游业在给目的地带来经济增长的同时,也会对其生态环境造成一定影响。既有研究多关注旅游业对生态环境的压力,而较少关注旅游业对目的地生态系统服务价值(Ecosystem service value, ESV)的影响。为此,研究以“旅游社会-生态系统”为基础,构建了旅游业对目的地ESV的影响框架。以神农架为例,基于土地利用格局变化以及修正ESV价值当量,计算其2005—2018年ESV以及时空变化特点。通过地理加权回归(Geographically weighted regression, GWR)与增强回归树(Boosting regression tree, BRT)模型对距居民点距离、距景区距离、距酒店距离以及距道路距离等旅游因素对ESV的影响以及空间差异进行了研究,并得到以下主要结论:(1)神农架土地利用格局变化显著,耕地、林地、草地和未利用地面积总体减少,水域及建设用地面积总体增加。(2)神农架ESV呈逐年递增趋势,由2005年的33.58亿元增加至2018年的89.10亿元。11项生态系统服务功能所占价值比例稳定,以气候调节、水文调节、土壤保持及生物多样性为主。ESV在空间上呈现...  相似文献   

20.
BACKGROUND: The occupational chemical 4-vinylcyclohexene (VCH) has been shown to cause destruction of small pre-antral follicles in ovaries of mice. Further, its monoepoxide metabolites, 1,2-VCH epoxide, 7,8-VCH epoxide, and the diepoxide, VCD, have been shown to cause pre-antral follicle loss in rats as well as mice. Chemicals that destroy small pre-antral follicles are of concern to women because exposure can result in premature ovarian failure (early menopause). METHODS: Studies working with these chemicals over the past decade have determined a number of aspects of the mechanism(s) of small pre-antral destruction, and a variety of questions have been answered. RESULTS: Specifically, it has been determined that the diepoxide (VCD) is the bioactive form and it directly targets the ovary in mice and rats. Mice are more susceptible to VCH than rats because they are capable of its metabolic bioactivation. Follicle destruction by VCD is selective for primordial and primary follicles. Mechanistic studies in rats have determined that VCD causes ovotoxicity by accelerating the natural process of atresia (apoptosis) and this requires repeated exposures. Pro-apoptotic signaling events in the Bcl-2 and mitogen activated protein kinase families have been shown to be selectively activated in fractions of small pre-antral follicles (targets for VCD). Finally, a whole ovarian culture system using neonatal mouse and rat ovaries has been developed to expand the potential for more in depth investigations into ovotoxicity caused by VCD. CONCLUSIONS: This article provides an overview of the questions asked and the approaches taken in studying VCH and VCD to support these conclusions.  相似文献   

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