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Sustainable agriculture options for production, greenhouse gasses and pollution alleviation.

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Abstract

Previous and current agricultural practices have contributed to environmental pollution, which is further affecting food security, human health, and climate. Yet, agriculture cannot be eliminated, because, of its promising role in ending hunger, reducing poverty, improving nutrition, and achieving food security in low-middle income countries. Hence, there is a need for shift from ‘unclean’ practices to sustainable practices. Similarly, differences in pollution, among nations call for regional changes or intervention in agri-food practices to reduce global pollution. These practices are essential for African and Asian countries. Of the many methods proposed in this review, localized technology improvement and globalized sustainable intensification are of high impact models having the potential of mitigating greenhouse gases upto an extentof 30%. Various methods of achieving these measures include, but not limited to, the shift in management systems of crop and livestock production, encouraging agriculture and veterinary practices with less environmental impact and high adaptation, enabling nutrient recycling or recovery, resource-use efficiency, mitigation of nitrous oxide and methane from soil, implementation of integrated farming system and insect farming. Government agencies along with agri-food producers, processors, and farmers must be ready to change their current agricultural practices by adopting new methods. The review conclude that the sustainable agricultural production is possible through the use of low-priced local resources that are capable of increasing soil carbon storage, thus combating the pollution in countries with a transition economy.

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During the last decade, a lot of research has been focused on identifying the methane yields achievable when using microalgae biomass (fresh and pretreated) as a substrate in anaerobic digestion. Encountered differences are frequently attributed to the different microalgae strains (cell walls and macromolecular profiles) or the different metabolic activities of anaerobic sludge used as inoculum. Nevertheless, under the hypothesis that the state of microalgae upon biomass storage may also play a significant role, this study was designed to evaluate the effect of biomass processing and storage on methane yields and hydrolysis kinetics in batch mode assays. Slight changes in the macromolecular profile distribution of the different tested biomass were observed. Regardless of the time that the biomass was stored, results revealed that frozen biomass doubled the hydrolysis constant and enhanced methane yield by 1.56-fold compared to fresh microalgae biomass (82.4 mL CH4 g COD in⁻¹). Similar enhancement was obtained with the freeze-dried biomass, and slightly lower values were obtained (1.34-fold) for the biomass kept at 4 °C longer than a week. Likewise, the semi-continuously operated reactor fed with microalgae biomass stored for 28 days at 4 °C did not show any effect in terms of methane production, although nitrogen mineralization was higher than expected. Remarkably, the initial stage of the biomass should be carefully considered for comparison purposes with the available literature on batch mode assays. This study highlights the importance of considering how the biomass is stored before the anaerobic digestion process to avoid misleading conclusions.
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Microalgae is considered as one of environmentally sustainable and potential feedstocks to produce biodiesels. However, recent studies on life cycle assessments (LCA) of microalgal buidiesels have shown that energy requirement is not small to produce biodiesel from microalgae, especially during cultivation stage. The costs for carbon sources, nutrients like nitrogen or phosphorous, and water for cultivation can contribute up to 80% of the total medium costs. In the present article, recent trends on the utilization of several promising nutrient sources such as municipal wastewaters, organic fertilizers, combustion exhaust emissions and organic solid wastes were reviewed, and the potential strategies to be used as substitutes of artificial culture media, especially for the biodiesel production, were discussed. © 2018, Korean Society of Industrial Engineering Chemistry. All rights reserved.
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Arenosols (sandy soils) in the Cerrado region of Mato Grosso, Brazil are increasingly used for maize production, the second most important crop in the region after soybean. Yet, these soils are typically nutrient poor with low soil water retention, requiring high fertilizer inputs that are often lost in surface runoff or leached. The addition of biochar, a more recalcitrant organic amendment, may therefore be beneficial in Cerrado Arenosols, contributing to sustainable crop production in the region. To examine biochar contribution to soil nutrient levels and maize growth in a Cerrado Arenosol, we conducted a greenhouse experiment using biochars made from local agricultural waste feedstocks. These were cotton husks, swine manure, eucalyptus sawmill residue, and sugarcane filtercake, pyrolized at 400°C and applied to soil at five rates: 0%, 1%, 2%, 3%, and 4% by weight. Maize plants were grown under unstressed conditions (e.g., no nutrient or water limitations) to highlight any possible negative effects of the biochars. After 42 days, soils were analyzed for nutrient levels, and plant physical and physiological measurements taken. Filtercake biochar had the highest plant biomass and physiological properties (e.g. photosynthesis, respiration, nitrogen use efficiency), while cotton biochar had the lowest. Importantly, maize biomass decreased with increasing application rates of cotton and swine manure biochars, while biomass did not vary in response to biochar application rate for filtercake and eucalyptus biochars. In this study we found that, while each biochar exhibited potential for improving chemical and physical properties of Cerrado Arenosols, filtercake biochar stood out as most promising. Biochar application rate was identified a key factor in ensuring crop productivity. Transforming these agricultural residues readily available in the region into more stable biochar can thus contribute to sustainable crop management and soil conservation, providing an alternative form of waste disposal for these residual materials.
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As global consumption expands, the world is increasingly facing threats to resource availability and food security. To meet future food demands, agricultural resource efficiency needs to be optimized for both water and nutrients. Policy makers should start to radically rethink nutrient management across the entire food chain. Closing the food loop by recycling nutrients in food waste and excreta is an important way of limiting the use of mineral nutrients, as well as improving national and global food security. This article presents a framework for sustainable nutrient management and discusses the responsibility of four key stakeholder groups—agriculture, the food industry, consumers, and waste management—for achieving an effective food loop. In particular, we suggest a number of criteria, policy actions, and supporting strategies based on a cross-sectoral application of the waste hierarchy.
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For centuries, wastewater has been improperly used in agriculture, presenting potential risks to public health and the environment. In the context of scientific development, and confronted by an increasing water crisis, wastewater reuse merits consideration because the practice helps decrease water use pressure and moderates water pollution. Thus, this article presents a literature review that addresses the effects, both positive and negative, of wastewater use in agriculture, emphasizing the effects on the soil environment. The literature review reveals that, until the 1990s, research studies promoted the use of wastewater for irrigation purposes from a treatment approach, while proposing "end of pipe" conventional solutions. However, more recent research studies (2012-2016) reveal that agricultural reuse significantly affects soil texture properties, while also causing possible alterations of the biomass and microbiota. In addition, research in this period has been oriented to the quantitative evaluation of microbiological risk.
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Changes in tropical wetland, ruminant or rice emissions are thought to have played a role in recent variations in atmospheric methane (CH4) concentrations. India has the world’s largest ruminant population and produces ~ 20% of the world’s rice. Therefore, changes in these sources could have significant implications for global warming. Here, we infer India’s CH4 emissions for the period 2010–2015 using a combination of satellite, surface and aircraft data. We apply a high-resolution atmospheric transport model to simulate data from these platforms to infer fluxes at sub-national scales and to quantify changes in rice emissions. We find that average emissions over this period are 22.0 (19.6–24.3) Tg yr⁻¹, which is consistent with the emissions reported by India to the United Framework Convention on Climate Change. Annual emissions have not changed significantly (0.2 ± 0.7 Tg yr⁻¹) between 2010 and 2015, suggesting that major CH4 sources did not change appreciably. These findings are in contrast to another major economy, China, which has shown significant growth in recent years due to increasing fossil fuel emissions. However, the trend in a global emission inventory has been overestimated for China due to incorrect rate of fossil fuel growth. Here, we find growth has been overestimated in India but likely due to ruminant and waste sectors.
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With a growing world population, increasingly demanding consumers, and a limited amount of agricultural land, there is an urgent need to find alternatives to conventional meat products. Livestock production is, moreover, a leading cause of anthropogenic-induced climate change. To mediate this, more sustainable diets are needed, with reduced meat consumption or the use of alternative protein sources. Insects are promoted as human food and animal feed worldwide. In tropical countries, edible insects are harvested from nature, but overexploitation, habitat changes, and environmental contamination threaten this food resource. Therefore, sustainable harvesting practices need to be developed and implemented. We provide examples of (1) aquatic insects whose populations are threatened by pollution, (2) caterpillar species in Africa that are disappearing due to overexploitation and habitat change, (3) edible insects species that are considered pests in agro-ecosystems, and (4) edible insect species that can be conserved and enhanced in forest management systems. Insect farming can be conducted either on small-scale farms or in large-scale industrialized rearing facilities. We review the environmental sustainability of insect farming compared to livestock production. The major environmental advantages of insect farming compared to livestock production are as follows: (1) less land and water is required; (2) greenhouse gas emissions are lower; (3) insects have high feed conversion efficiencies; (4) insects can transform low-value organic by-products into high-quality food or feed; and (5) certain insect species can be used as animal feed or aqua feed. For instance, they can replace fish meal, which is becoming increasingly scarce and expensive. However, edible insect species intended for production should be screened for risks to humans, animals, plants, and biodiversity.
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The intensification of beef cattle production in dryland areas of East Indonesia has the potential to substantially raise the incomes of smallholder farmers that dominate the sector. In this study we assess the potential for intensifying beef production on Sumbawa Island, by introducing a household feedlot production system (2–20 animals) based on the Leucaena leucocephala (leucanea) tree legume as an improved source of feed. We used a system dynamics approach to model the entire value chain, accounting for herd dynamics, demand dynamics and seasonality. Our findings complement the growing body of biophysical evidence about the potential success of this intervention, by simulating improvements in the annual profitability for beef farmers in the project area of up to 415% by 2023. Increases in farm profit were shown to depend near equally on the higher productivity of the leucaena feeding system and an associated price premium, demonstrating the importance of supporting improved agricultural production with better marketing practices. The intervention was also shown to generate positive or neutral benefits for the main post-farm value chain actors. Importantly, it also reduced the GHG emission intensity of outputs from the beef herd by 16% by 2020. We explored number of scale-out pathways, including a relatively moderate pace of autonomous adoption for our main analysis, resulting in the accumulation of 3,444 hectares of leucaena 20-years after the initial project phase, which could sustain the fattening of 37,124 male cattle per year. More ambitious rates of scale-out were found to be possible without exceeding the animal and land resources of the island. © 2017 Dahlanuddin et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
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The study assessed the effect of Acacia mearnsii tannin extract supplementation grazing dairy cows on dry matter (DM) intake, enteric methane (CH4) emission, and performance. Twelve Holstein cows were divided into two groups and subjected to two treatments that consisted of millet pasture (Pennisetum glaucum L.) plus supplementation with 6 kg of concentrate (750-g/kg ground corn and 250-g/kg soybean meal) including or excluding 120-g tannin extract. The trial design was a double reversal using three periods of 28 days each, with 21 days for the adaption period, and 7 days for sample collection. Herbage intake was measured using the n-alkane technique, and daily CH4 emission was measured with the sulfur hexafluoride tracer gas technique. Individual total DM intake (mean = 17.1 kg/day), herbage DM intake (mean = 11.8 kg/day), and milk production (mean = 19.2 kg/day) were similar between treatments. CH4 emission significantly decreased (32%, P < 0.05) in the animals supplemented with tannin extract, compared to non-supplemented animals. On the other hand, as proportion of DM intake or milk production, methane emission tended to decrease in tannin-supplemented animals. Supplementing dairy cows grazing a millet pasture with 120-g tannin extract reduced daily CH4 emission without affecting animal performance.
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Arenosols in the Brazilian Cerrado are increasingly being used for agricultural production, particularly maize. These sandy soils are characterized by low soil organic matter, low available nutrients, and poor water-holding capacity. For this reason, adding biochar as a soil amendment could lead to improved water and nutrient retention. A greenhouse experiment was carried out using twelve biochars derived from four feedstocks (cotton husks, swine manure, eucalyptus sawmill residue, sugarcane filtercake) pyrolized at 400, 500 and 600 • C and applied at 5% w/w. The biochars' effect on maize biomass was examined, along with their contribution to soil physical properties including water retention, electrical conductivity (EC), and grain size distribution. After six weeks, maize plants in soils with eucalyptus and particularly filtercake biochar had higher biomass compared to those in soils with cotton and swine manure biochars. The latter's low biomass was likely related to excessive salinity. In general, our biochars showed potential for increasing θ in sandy soils compared to the soil alone. Filtercake and eucalyptus biochars may improve soil aeration and water infiltration, while applying cotton and swine manure biochars at levels <5% to avoid high salinity could contribute to improved soil water retention in Cerrado Arenosols.
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The aim of the study was to evaluate the effect of supplementation of Delonix regia (DR) seed meal containing tannins and saponins on gas kinetics, ammonia-nitrogen (NH3-N) content, pH, methane (CH4) production and dry matter (DM) digestibility using an in vitro gas production technique. The experimental design was completely randomized, and the dietary treatments included DR seed meal supplementation at levels of 0, 3.3, 5.0, 6.7, 8.3, 10, 11.7, 13.3, 15.0 and 16.7 mg DM added to 0.5 g of roughage and concentrate (70:30) mixture. The gas production was measured at several time points: 0, 0.5, 1, 2, 4, 6, 8, 12, 18, 24, 48, 72 and 96 h by a pressure transducer. The parameters of gas kinetics and cumulative gas production were not altered (P > 0.05), except for gas production rate constant for the insoluble fraction which was the highest at 11.7 mg DR seed meal inclusion. CH4 production and total protozoa counts linearly decreased with increasing DR seed meal levels (P < 0.05). DR seed meal addition caused quadratic increase of in vitro DM digestibility with the highest value at 11.7 mg DR seed meal inclusion. No significant difference in volatile fatty acid profile (P > 0.05) was stated between treatments except for propionic acid. In conclusion, supplementation of DR seed meal resulted in improved in vitro gas kinetics and DM digestibility up to 11.7 mg level, while CH4 production was reduced linearly. The further in vivo studies are necessary to examine practical of DR seed meal usage in animal production.
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Methane (CH4) and nitrous oxide (N2O) are two important greenhouse gases (GHGs) that are emitted into the atmosphere by livestock during the process of enteric fermentation and manure management. Developing countries produce a large quantity of those emissions, caused mainly by inefficient animal rearing systems, feed production and manure management. This paper outlines the CH4 and N2O emitted from livestock in developing countries and the mitigation actions that could be put in place to reduce atmospheric emissions and increase animal productivity. Emission intensity expresses emission (CO2 equivalents) per unit of product and describes it in relation to the capacity of local animals to produce from local resources. Developing countries are characterized by low production per animal and, consequently, high emission intensity. The emission intensity of dairy cattle in developing countries ranges from 2 to 9 kg CO2-eq/kg fat and protein corrected milk (FPCM) and in only a few cases is below 2 kg CO2-eq/kg FPCM. In sub-Saharan Africa, the average emission intensity is 7.5 kg CO2-eq/kg FPCM for dairy cattle, 71 kg CO2-eq/kg of carcass weight for beef cattle, 6.9 kg CO2-eq/kg FPCM for sheep and goats, and 5 kg CO2-eq/kg eggs for chickens. Taking into account the limited economic and technical resources in most developing countries, the application of appropriate mitigation tools is recommended to reduce the emissions of CH4 and N2O gases in the atmosphere. Increasing livestock productivity through selection and feeding is the most effective tool to reduce emission intensity.
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The objective of this experiment was to determine the digestibility of rice straw fermented for 28 days with the fungus Pleurotus eryngii. Four Phan Rang sheep with body weight of 20.5 kg (±0.42 kg) were allocated to a changeover design with three treatments (consecutive periods each of 20 days). In period 1 the diet was 100% of guinea grass (1:GG); in the second period it was 30% FTR + 70% GG (2:FTR); in the third period it was 30% RS and 70% GG (3:RS:GG). In each period, the first 14 days were for adaptation to the diet followed by 6 days of measurements of feed intake and digestibility. The growth of the fungus reduced the content of NDF, ADF and ADL, enhanced the content of crude protein (from 4.2 to 7.1% in DM), and the digestibility of DM (from 43 to 53%) and of the crude protein (from 45.8 to 54.4%). Over the 28-day treatment period, 14.8% of the straw biomass was catabolized.
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After entering the twenty-first century, biochar has become a focal point of multidisciplinary research because of its special characteristics, broad application, and promising development prospects. Basic and applied research on the application of biochar in the areas of agriculture, environment, and energy have increased dramatically in the face of food security, environmental pollution, and energy shortage. Although there are some disputes about biochar research, many studies have demonstrated the importance of biochar research from the perspective of scientific advancement and practical application. This paper briefly recalls the history of biochar application; introduces research progress on the basic characteristics of biochar and its associated production technologies; summarizes the research status and existing problems of biochar application in the areas of agriculture, environment, and energy; and analyzes the potential problems and development trends of biochar research in the future.
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There is an urgent need to develop agricultural methods that balance water supply and demand while at the same time improve resilience to climate variability. A promising instrument to address this need is biochar – a charcoal made from pyrolyzed organic material. However, it is often unclear how, if at all, biochar improves soil water availability, plant water consumption rates and crop yields. To address this question, we synthesized literature-derived observational data and evaluated the effects of biochar on evapotranspiration using a minimal soil water balance model. Results from the model were interpreted in the Budyko framework to assess how climatic conditions mediate the impacts of biochar on water fluxes. Our analysis of literature-derived observational data showed that while biochar addition generally increases the soil water holding capacity, it can have variable impacts on soilwater retention relative to control conditions. Our modelling demonstrated that biochar increases long-term evapotranspiration rates, and therefore plant water availability, by increasing soil water retention capacity – especially in water-limited regions. Biochar amendments generally increased crop yields (75% of the compiled studies) and, in several cases (35% of the compiled studies), biochar amendments simultaneously increased crop yield and water use efficiencies. Hence, while biochar amendments are promising, the potential for variable impact highlights the need for targeted research on how biochar affects the soil-plant-water cycle.
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Although air pollution is well-known to be harmful to the lung and airways, it can also damage most other organ systems of the body. It is estimated that about 500,000 lung cancer deaths and 1.6 million chronic obstructive pulmonary disease (COPD) deaths can be attributed to air pollution, but air pollution may also account for 19% of all cardiovascular deaths and 21% of all stroke deaths. Air pollution has been linked to other malignancies, such as bladder cancer and childhood leukemia. Lung development in childhood is stymied with exposure to air pollutants, and poor lung development in children predicts lung impairment in adults. Air pollution is associated with reduced cognitive function and increased risk of dementia. Particulate matter in the air (PM2.5) is associated with delayed psychomotor development and lower child intelligence. Studies link air pollution with diabetes mellitus prevalence, morbidity, and mortality. Pollution affects the immune system and is associated with allergic rhinitis, allergic sensitization, and autoimmunity. It is also associated with osteoporosis and bone fractures, conjunctivitis, dry eye disease, and blepharitis, inflammatory bowel disease, increased intravascular coagulation, and decreased glomerular filtration rate. Atopic and urticarial skin disease, acne, and skin aging are linked to air pollution. Air pollution is controllable and, therefore, many of these adverse health effects can be prevented.
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The black soldier fly [Hermetia illucens L. (Diptera: Stratiomyidae)] can be sustainably reared on organic waste streams and thereby provide a novel animal protein source for animal feed. Black soldier fly’s performance and body composition depend to a large extent on the nutrient composition of the waste stream. Black soldier fly larvae were fed on four diets consisting of vegetable by-products from the food industry. All four diets contained dried distiller’s grains with solubles plus one or two other main ingredients; for diet 1 the additional ingredient was grape pulp; diet 2: potato peels; diet 3: bean seeds; and diet 4: cabbage leaves plus old bread. The diets were formulated based on an optimal summed protein and carbohydrate (P+C) concentration resulting from previous experiments and a 1:2 protein:carbohydrate (P:C) ratio. We quantified both larval and adult performance. Diet 4 was the best performing vegetable waste-based diet. In a follow-up experiment, we re-formulated diet 4 to have P:C ratios of 1:2 or 1:3 and 40 or 47% dry matter of P+C. In the first experiment, although there were differences in larval performance among the diets, all diets supported a higher larval performance than reported previously, with diet 4 having 47% P+C being the best performing diet. We infer that not only total macronutrient content but also nutritional quality of proteins and carbohydrates affected performance. In the second experiment, the two vegetable residue-based larval diets resulted in similar larval and adult performance. High dietary protein resulted in increases in larval crude fat content.
Chapter
Insects have been an important part of food culture for many different places and peoples across North America’s history. This chapter retraces the indigenous uses of insects as a food across the continent, through modern Mexico and into the present day movement to bring these ingredients into the culinary landscape of the United States of America and Canada. The authors provide an overview of the practices and uses of insects as food in both whole and traditional forms, and newer abstractions of the insects into consumer facing snack food products. In addition, the ways in which these startup farms and product makers are using insects for food are discussed, including facets such as crowdfunding, processing and marketing, as well as evidence from the culinary and celebrity worlds that entomophagy is gaining traction in North America.
Chapter
Already in the early phases of the development of a European insect industry, aquafeed was suggested as one of the first animal feeds where insect products could be implemented. Since then, substantial progress has been made by the research community and feed producers to test various types of insect species and insect products as part of a complete feed for aquaculture. These (mostly extruded) feeds are typically high in energy and protein content which demands specifics characteristics of the raw materials. The role insects, high in protein and lipids, can play in these diets will be reviewed and discussed in this chapter. We will shortly touch on topics like the effect of insect feeding substrate, insect processing and chitin that all can have an effect on insect meal. Finally, feed safety considerations related to the use of insects in aquafeeds will be reviewed and discussed.
Chapter
This chapter systematically compares and contrasts the known environmental impacts of traditional vertebrate animal production with insect production intended for both food and animal feed. There are major physiological and biological differences between traditional livestock species and insects, which often translate into lower environmental impacts from insect production. However, insect production systems are still in their infancy and there are still major improvements to be made. Based on our analysis, the greatest potential of insects is the prospect of feeding them various kinds of waste products from agriculture, industry and households. This chapter can serve as a reference guide for future research into the environmental impacts of insects for food and feed.
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Tetracyclines are one of the most widely used class of veterinary and human antibiotics. The conventional treatment of wastewater based on activated sludge is not effective to remove antibiotics and their residues are still biologically active, which represents a problem in terms of bacterial resistance. The main objective of this work is to assess ability of stevensite and two biochars to adsorb three tetracycline antibiotics from water. Batch adsorption experiments were carried out to test the ability of these materials to adsorb tetracyclines. Then desorption experiments were performed to determine the adsorption strength on stevensite. In order to elucidate the adsorption mechanism of tetracyclines on stevensite, cation exchange analysis and spectroscopic analyses by IR and XRD were performed. The adsorption of tetracyclines on stevensite was tested on continuous system with water artificially contaminated. Finally, the designed filter was validated with tetracyclines spiked wastewater. The two biochars and stevensite were able to adsorb between 60 and 100% of the tetracyclines present in the batch system. Stevensite was the material with the highest tetracyclines removal capacity (around 100% at low concentrations of tetracyclines). Biochars showed less affinity for tetracyclines adsorption (70%). Tetracyclines desorption from stevensite reached values lower than 10% for low tetracyclines concentrations. The IR spectroscopy suggested that cation exchange is the main mechanism of tetracyclines adsorption on clay and also proved the role of amide and amine groups in this adsorption. The cation exchange mechanism was confirmed by displacement of Ca and Mg from stevensite. A continuous wastewater flow through a system composed by stevensite leaved this system with no tetracyclines, indicating water purification by tetracyclines adsorption in clay.
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The aim of the present study was to evaluate the animal performance, haematochemical parameters, intestinal morphology and histological features of broiler chickens fed diets including Tenebrio molitor (TM) larvae meal. A total of 160 female broiler chicks (Ross 708) at one-day of age were randomly allotted to four dietary treatments: a control (C) group and three TM groups, in which TM meal was included at 50 (TM50), 100 (TM100) and 150 (TM150) g/kg, respectively. Each group consisted of five pens as replicates, with eight chicks per pen. After the evaluation of growth performance and haematochemical parameters, two birds per pen were slaughtered at 40 days and carcass traits were recorded. Morphometric investigations were performed on duodenum, jejunum and ileum and histopathological alterations were assessed for liver, spleen, thymus, bursa of Fabricius, kidney and heart. The live weight (LW) showed a linear (12 days, P < 0.05, maximum with TM150) and quadratic response (40 days, P < 0.05, maximum with TM50) to dietary TM meal inclusion. The average daily gain (ADG) showed a linear increase (1-12 days, P < 0.05, maximum with TM150) in response to TM meal utilization. A linear effect (1–12 and 12–25 days, P < 0.01 and P < 0.05, maximum with TM150 and TM50) was observed for the daily feed intake (DFI). The feed conversion ratio (FCR) showed a linear response to TM utilization in the period 12–25 days (P < 0.01, maximum with TM150). A quadratic effect (P < 0.05, maximum with TM50) was observed for the carcass weight. The abdominal fat weight and percentage showed a linear response to dietary TM meal inclusion (P < 0.05 and P < 0.01, maximum with TM150 and TM100). A quadratic increase (P < 0.05, maximum with TM100) was observed for the erythrocytes, while the albumin and GGT showed a linear and quadratic decrease (P < 0.05, minimum with TM100) in relation to TM utilization. Gut morphology and histopathological findings were not significantly influenced (P > 0.05) by dietary TM meal inclusion. The present study suggests that increasing levels of dietary TM meal inclusion in female broiler chickens diets may improve body weight and feed intake, but can partially worsen feed efficiency. However, positive effects on carcass traits and haematochemical parameters related to TM meal utilization are observed, along with no negative influence on gut morphology and histological findings.