Poultry Litter Research Articles

Evaluating antibiotic occurrence, degradation, and environmental risks in poultry litter within Argentina's agricultural hub

This study explores the relationship between poultry farming's antibiotic administration practices and residual antibiotic levels in the litter before its application onto agricultural soils. Twenty-three antibiotics were performed across 19 Argentinean farms representing diverse antibiotic management practices. Analysis revealed up to 20 antibiotics from eight chemical classes in poultry litter samples, with tylosin, enrofloxacin, and salinomycin being the most relevant drugs. Farms with restricted antibiotic use in feed exhibited lower residual concentrations. A self-heating treatment was tested to reduce litter antibiotic levels. Although a 60 % reduction of antibiotics was found after treatment, prevalent compounds persisted at residual levels. Regulatory measures and comprehensive litter treatments pre-application are crucial to mitigate environmental risks. This is the first study that provides insight on the occurrence of >20 drugs in real poultry production scenarios from Latin America and demonstrates how relatively simple treatments can be readily applied to decrease the associated environmental risks.

Ammonia Capturing Capacity of Biochar and Kaolinite

Emission of ammonia from poultry litter has numerous negative impacts on poultry, poultry house workers and the environment. When applied as a litter amendment, acidified biochar (ABC) and Kaolinite are reported to lower the emission of ammonia. Apart from reducing ammonia formation, both amendments have a capacity to capture ammonia before being released into the environment. However, capacity of those materials to capture ammonia has not been estimated. The objective of this study was to determine the ammonia capturing capacity of ABC, kaolinite and three different mixtures of them; 75% Kaolinite and 25% ABC, 50% kaolinite and 50% ABC and 25% kaolinite, 75% ABC. Each of the five amendment mixture was tested in five separate completely randomized design experiments. Poultry litter samples were incubated in ten sealed-conical flasks; each fitted with flexible tubes through which emitting ammonia was conveyed to another sealed-flask containing either a known weight of amendment (five replicate flasks) or Styrofoam; control (five replicate flasks). The weight of the amendment or Styrofoam was adjusted to have same volume of material in flasks. A flexible tube originating from the second flask was connected to another sealed-flask containing a boric acid solution so that ammonia that has not been captured by the amendment or Styrofoam in the second flask is captured. A set of tubes originating from each of the ten boric acid flasks were fitted to a vacuum pump.N content, pH, dry matter percentage of the litter before and after the incubation and the amount of N captured by the boric acid were determined. The difference between N released and that captured by the boric acid solution was considered to be captured by the material added to the second flask. Though assumed to have no capacity to capture ammonia, in all five experiments, Styrofoam reported significantly higher ammonia capturing capacity compared to respective amendments. Ammonia capturing capacity of Styrofoam was as high as 1.24g/100g/hr while that of ABC and Kaolinite were 0.40g/100g/hr and 0.14g/100g/hr), respectively. In all five experiments, the percentages of ammonia captured (of the total released during incubation) were not significantly different between tested amendments and the Styrofoam. Percentage capture of ammonia by ABC, Kaolinite and Styrofoam were 91%, 83% and 84%, respectively. The study concludes that acidified biochar, Kaolinite and Styrofoam have capacity to capture ammonia releasing from poultry litter. Further studies are needed to understand the nature of capturing. 
 Keywords: Ammonia, Biochar, Kaolinite, Litter, Poultry

Effects of Salvinia as a broiler litter material on growth performance, behavior, welfare parameters, litter characters, and ammonia emission

The type of litter material has direct impacts on production, behavioral, and welfare parameters of broilers. The price of conventionally-used litter materials is increasing. Salvinia molesta is a fast-growing aquatic plant which has become an environmental issue in some areas. This study assessed the suitability of air-dried Salvinia plants (SAL) as an alternate litter material to paddy husk (PH). Resulting in a completely randomized experiment, a total of 240 broilers was raised in 12 floor-pens each provided with either PH or SAL as litter materials, from 11 to 36 d. Scan sampling technique was employed to record the birds' engagement in 15 predetermined behaviors. Foot pad dermatitis (FPD), hock burn damage (HBD) and plumage cleanliness (PC) were assessed using Welfare Quality Scoring System. Litter samples were analyzed for pH, dry matter%, water holding capacity, porosity, N%, tapped-density and ammonia emission rate. The litter material had no significant effect (P > 0.05) on mortality, growth performance parameters, dressing % and visceral organ weight. The scores for FPD and PC were unaffected by the litter materials. SAL litter reported significantly lower (P < 0.05) HBD scores. The percentages of birds engaged in eating and wing flapping behaviors were significantly lower on SAL. Litter type had no significant influence on the color, aroma, flavor, texture and overall acceptability of breast meat. Air-dried Salvinia plants reported acidic pH. SAL litter gave a significantly higher tapped-density. Ammonia emission rate of SAL litter was significantly lower than that of PH. However, the final litter N content was higher for PH (3.7%) than SAL (3.2%). The study proposes air-dried Salvinia plants as a litter material for broilers since it gives growth performance comparable to PH with reduced hock burn damage incidences. Effects of SAL on behavior and the fertilizer value of the spent litter are to be studied further.

Adsorption and partition of the antibiotic ciprofloxacin in poultry litter

AbstractBACKGROUNDThe use of antibiotics on a large scale is a common practice in poultry farming. This research investigated the adsorption of the antibiotic ciprofloxacin (CIP) in poultry litter samples to assess the potential risk to ecosystems as a result of the compound mobility. This residue is used directly dispersed in agricultural soils as a biofertilizer.RESULTSExperimental data were evaluated in terms of fits of isotherm models. The mobility of CIP was assessed by the distribution coefficient and the partition coefficient related to organic matter. The studied poultry litter presented a pH of 8.5 ± 0.1, moisture content of 20.3 ± 1.3% and total solids content of 79.8 ± 1.2%, with a high amount of both inorganic matter (57.1 ± 1.7%) and organic matter (42.9 ± 1.7%) content in its composition. The Redlich–Petersen isotherm model satisfactorily described the experimental data, with higher maximum adsorption capacities at more alkaline pHs (pH 8.0 = 3015.0 ± 118.0 μg g−1, pH 7 = 2916.6 ± 1152.9 μg g−1 and pH 6 = 410.0 ± 18.1 μg g−1). The log Kd (pH 6 = 0.9, pH 7 = 1.2, and pH 8 = 1.4) and log Koc (pH 6 = 1.3, pH 7 = 1.7 and pH 8 = 1.8) values obtained for the sorption of ciprofloxacin at different pHs in poultry litter were considered low (log Koc &lt; 3.5).CONCLUSIONSThe analyte does not tend to adsorb in the poultry litter and might leach to other environmental compartments. The information obtained in this study reinforces the ecotoxicological concern about antibiotic residues in the environment. © 2024 Society of Chemical Industry (SCI).

Evaluation of Lignocellulosic Biomasses for Pyrolysis Product Generation

This study aimed to assess agroindustrial residues, namely acerola seeds, poultry litter, bean pods, corn cobs, coconut fiber, pine nut shells, peanut shells, pine, and passion fruit, for the production of pyrolysis products, thereby adding value to these environmental assets. The characterization of these biomasses was carried out through elemental analysis (CHN), thermogravimetry (TG), higher heating value (HHV), ash content, and protein content determination. The samples exhibited low ash content (1.04% to 11.92%), protein content (1.22% to 15.06%), and moisture content (7.82% to 15.31%). Thermogravimetric analysis revealed that compound degradation occurred between 115°C and 500°C, with higher heating values (16.73% to 19.94 MJ.kg⁻1), indicating strong applicability in pyrolysis processes.

A Multi-Residue Analytical Method for Assessing the Effects of Stacking Treatment on Antimicrobial and Coccidiostat Degradation in Broiler Litter.

Antimicrobial drugs and coccidiostat compounds are commonly used in poultry farming. These compounds are subsequently excreted and released into the environment via broiler litter (BL) and can re-enter the food chain as fertilizer or animal feed. Such residue in animal feed can encourage the appearance of antibiotic-resistant bacteria as well as toxicity. Most analytical methods used to identify and quantitate these drug residues are traditional, and are specific to some antimicrobials and present limitations in assessing complex matrixes like BL. The aim of this study was to develop a multi-residue analytic method for assessing 30 antimicrobial drugs and coccidiostats associated with BL. We investigated the presence and the effects of biotic stack treatment on the degradation of drug residue in BL. Liquid-liquid extraction (LLE) and solid phase extraction (SPE) were replaced by Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) clean-up steps and detected by liquid chromatography mass spectrometry (LC/MS/MS). Results show that a wide spectrum of residues were detected from 0.4 to 8.9 mg kg-1. Following lab-scale stacking treatment, tilmicosin and eight coccidiostats persisted in BL (26-100%). This research supports the need for better understanding, regulation, and management of the use of BL that might carry a high risk of residue drugs.

Cover Crop and Crop Rotation Effects on Tissue and Soil Population Dynamics of Macrophomina phaseolina and Yield Under No-Till System.

The effects of crop rotation and winter cover crops on soybean yield and colony-forming (CFU) units of Macrophomina phaseolina, the causal agent of charcoal rot (CR), are poorly understood. A field trial was conducted from 2011 to 2015 to evaluate (i) the impact of crop rotation consisting of soybean (Glycine max [L.] Merr.) following cotton (Gossypium hirsutum L.), soybean following corn (Zea mays L.), and soybean following soybean over a 2-year rotation and its interaction with cover crop and (ii) the impact of different cover crops on a continuous soybean crop over a 5-year period. This trial was conducted in a field with 10 subsequent years of cover crop and rotation treatments. Cover crops consisted of winter wheat (Triticum aestivum L.) and Austrian winter pea (Pisum sativum L. subsp. sativum var. arvense), hairy vetch (Vicia villosa Roth), and a fallow treatment was evaluated with and without poultry litter application (bio-cover). Tissue CFU of M. phaseolina varied significantly between crop rotation treatments: plots where soybean was grown following cotton had significantly greater tissue CFU than plots following soybean. Poultry litter and hairy vetch cover cropping caused increased tissue CFU, though this effect differed by year and crop rotation treatment. Soil CFU in 2015 was substantially lower compared with 2011. However, under some crop rotation sequences, plots in the fallow treatment had significantly greater soil CFU than plots where hairy vetch and wheat was grown as a cover crop. Yield was greater in 2015 compared with 2011. There was a significant interaction of the previous crop in the rotation with year, and greater yield was observed in plots planted following cotton in the rotation in 2015 but not in 2011. The result from the continuous soybean planted over 5 years showed that there were no significant overall effects of any of the cover crop treatments nor was there interaction between cover crop treatment and year on yield. The lack of significant interaction between crop rotation and cover crop and the absence of significant differences between cover crop treatments in continuous soybean planting suggest that cover crop recommendations for midsouthern soybean growers may need to be independent of crop rotation and be based on long-term crop needs.

Economics of vermi-composting of cattle dung, sheep manure and poultry litter under temperate agro-climatic conditions of Kashmir valley

Economics of vermi-composting of cattle dung, sheep manure and poultry litter under temperate agro-climatic conditions of Kashmir valley

Assessment of the combined inputs of antimicrobials from top soil improvers and irrigation waters on green leafy vegetable fields

Sustainable food systems involve the recycling of biowaste and water. This study characterizes thirty-one top soil improvers of anthropogenic, animal, and green waste origin, along with eleven irrigation waters from rivers, channels, and civil wastewater treatment plants (cWWTPs) for the presence of antimicrobials. Liquid chromatography coupled with hybrid High-Resolution Mass Spectrometry (LC-HRMS/MS) was employed to identify forty-eight drugs belonging to the classes of sulfonamides (11), tetracyclines (7), fluoroquinolones (10), macrolides (12), amphenicols (3), pleuromutilins (2), diaminopyrimidines (1), rifamycins (1) and licosamides (1). Sludge from cWWTPs, animal manure, slurry, and poultry litter exhibited the highest loads for sulfonamides, tetracyclines, fluoroquinolones and macrolides (80, 470, 885, and 4,487 ng g−1 wet weight, respectively) with nor- and ciprofloxacin serving as markers for anthropogenic sources. In compost and digestate, antimicrobials were found to be almost always below the limits of quantification. Reused water from cWWTPs for irrigation in open-field lettuce production were contaminated in the range of 12-221 ng L−1 with sulfonamides, tetracyclines, and fluoroquinolones, compared to very few detected in channels and surface waters. The Antimicrobials Hazard Index (HI), based on the Predicted No Effect Concentration for Antimicrobial Resistance (PNECAMR), was significantly >100 in contaminated topsoil improvers from urban and animal sources. Accounting for worst-case inputs from topsoil improvers and irrigation water, as well as dilution factors in amended soil, fluoroquinolones only exhibited an HI around 1 in open fields for lettuce production. The origin of topsoil improvers plays a pivotal role in ensuring safe and sustainable leafy vegetable production, thereby mitigating the risk of Antimicrobial Resistance (AMR) onset in food-borne diseases and the transfer of AMR elements to the human gut flora.

Effect of Biochar Type and Amendment Rates on Soil Physicochemical Properties: Potential Application in Bioengineered Structures

Abstract Biochar has recently gained attention as a potential soil amendment for its usage in bioengineered structures, e.g., landfill cover system, green slopes, green corridor, etc., that usually comprises compacted soil with vegetation. In literature, many studies have explored the effect of biochar sourced from plant (agri-residues, wood)- and animal-based biomass on physicochemical properties of soil suitable for agricultural application. However, systematic study rarely has been conducted for soil suitable for bioengineered structures, and contradictory results have been reported. The objective of the present study is to explore the effects of biochar produced from different feedstock types (poultry litter, water hyacinth, and sawdust) on physicochemical properties of soil for bioengineered structures application. The results revealed that the amendment of biochar increased the liquid limit (14–52 %), plastic limit (PL, 2–66 %), optimum moisture content (OMC, 4–50 %), pH (29–59 %), cation exchange capacity (20–428 %), and water absorption capacity (12–94 %), whereas it decreased the maximum dry density (7–17 %), specific gravity (3–17 %), and shrinkage area ratio (SAR, 22–57 %) of the soil. Among the different biochar types tested, water hyacinth biochar (WHB) exhibited the highest increase in PL, OMC, and pH, and decrease in specific gravity and SAR of the soil after amendment, whereas poultry litter biochar showed the lowest variation of the same. These changes in the soil physicochemical properties after biochar amendment are likely attributed to the presence of intrapores and active chemicals in biochar, which are highly dependent on feedstock types. The findings of the present study could be useful in understanding the hydro-mechanical and plant interaction of biochar-amended soil (BAS), and potential implementation of BAS in bioengineered structures.

Influence of Soil Type and Temperature on Nitrogen Mineralization from Organic Fertilizers

Organic vegetable producers in Georgia, USA, utilize a range of amendments to supply nitrogen (N) for crop production. However, differences in soil type, fertilizers and environmental conditions can result in variability in N mineralization rates among commonly utilized organic fertilizers in the region. In this study, the effects of temperature on N mineralization from three commercial organic fertilizers [feather meal (FM), pelleted poultry litter (PPL) and a mixed organic fertilizer (MIX)] in two soil types from Georgia, USA (Cecil sandy clay loam and Tifton loamy sand) were evaluated for 120 d. Net N mineralization (Net Nmin) varied with soil type, fertilizer and temperature. After 120 d, Net Nmin from the FM fertilizer ranged between 41% and 77% of total organic N applied, the MIX fertilizer ranged between 26% and 59% and the PPL fertilizer ranged between 0% and 22% across all soil types and temperatures. Incubation at higher temperatures (20 °C and 30 °C) impacted Net Nmin of FM fertilizer in the Tifton series soil. Temperature and soil type had a relatively minor impact on the potentially mineralizable N of the PPL and MIX fertilizers after 120 d of incubation; however, both factors impacted the rate of fertilizer release shortly after application, which could impact the synchronicity of N availability and plant uptake. Temperature-related differences in the mineralization of organic fertilizers may not be large enough to influence a grower’s decisions regarding N fertilizer inputs for vegetable crop production in the two soils. However, organic fertilizer source will likely play a significant role in N availability during the cropping season.

Production of Biogas From a Mixture of Chicken Litter and Cow Manure and Its Effect on the Resulting Volume and C/N Ratio

The livestock sector's waste is a potential raw material for producing biogas because it is abundantly available. This experiment aimed to understand the potential of two types of livestock waste to produce biogas. The two sources of raw material were mixed with different variations. The results showed that the volume of fermentation gas produced from livestock waste varied depending on the type and composition of the raw material used. Mixing was done to determine the best variation in producing biogas from chicken litter and cow manure. The volume ratio of litter to cow manure used was (0%:100%), (25%:75%), (50%:50%), (75%:25%), (and 100%:0%), with a total volume of 2 liters. In addition, 10% of EM-4 (effective microorganism) was added to the mixture of livestock waste that had previously been given 2 liters of water. The waste mixture was then fermented for 30 days. The fermentation process was carried out under mesophilic conditions at room temperature and pressure. This study showed that the higher the concentration of chicken litter in the mixture, the higher the carbon-to-nitrogen (C/N) ratio value. On the other hand, if there is a higher composition of cow manure in the mixture, the substrate pH value will be higher. Furthermore, a 50%:50% composition of chicken litter and cow manure produced a high volume of biogas. Similarly, the biogas formation rate in this composition showed the best performance. These results prove that the balance of carbon and nitrogen composition, temperature, and substrate acidity significantly affect biogas production.

Biomass Electricity Generation Using Industry Poultry Waste

This work presents study details of a biomass based electricity generation project. The biomass used was industrial poultry litter. The objective of the work is to contribute to the research of poultry waste use in real life applications. In this sense, a case study is presented. The case study is an aviary industry region of southern Brazil, where is evaluated the technical and economic characteristics of power generation using biomass obtained from poultry litter. Still, it is highlighted the large energy potential and the high poultry litter production in the region, which translates into a important source of raw material for electricity generation, currently not highly explored in Brazi

Poultry litter: great potential for electrical energy generation in Brazil

Due to the rapid industrialization and population growth there is a higher energy demand. As a result of this factor the greenhouse effect has been aggravating the weather around the globe. Many countries are seeking for sources of renewable and clean energy in order to reduce the air pollution. The biomass energy is an alternative that may interest everyone, since it is a renewable source and there are several technologies for its processing. This study aims to quantify the generation of poultry litter in the production of broiler chickens in the country, to identify the technologies for the available energy conversion, to quantify the potential for electrical energy generation and indicate through technical analysis the most feasible technology to explore the energy potential. In Brazil the biomass derived from the poultry litter represents 1% of all the available biomass, compared to the straw and sugar cane bagasse, regarding the biomass used in the electrical energy generation this percentage increases to 7%. Using the process which is more efficient (gasification) with the poultry litter produced in the country in 2010 (8.23 X 109 kg), it is estimated a production of 503.77MW. This energy may be injected into the network to meet the demand at times of increased consumption.

Combining lime and organic amendments based on titratable alkalinity for efficient amelioration of acidic soils

Abstract. Ameliorating soil acidity using a combination of lime and organic amendments (OAs) can be an alternative to lime alone, but determining the appropriate OA rates can be difficult. We developed a new method for calculating the combined application rate of lime and OAs (wheat straw, faba bean straw, blended poultry litter, biochar, and compost) that is based on the titratable alkalinity of OAs and the equilibrium lime buffer capacity (LBCeq) of acidic soils. The effect of calculated soil amendment rates on soil pH was validated at soil water contents of 60 %, 100 %, and 150 % of field capacity (FC). The soil used to develop and validate the method was a sandy loam with a soil pH in deionised water (pHW) of 4.84 and a soil pH in 0.01 M CaCl2 solution (pHCa) of 4.21. The LBCeq of the soil was 1657 mg CaCO3 kg−1 pH−1 (where “CaCO3 kg−1 pH−1” denotes the amount of lime required to raise the pH of 1 kg of soil by one unit). The titratable alkalinity of the OAs ranged from 11.7 cmol Heq+ kg−1 for wheat straw to 357 cmol Heq+ kg−1 for compost. At 60 % FC, faba bean and wheat straw amendment increased the soil pHW to 6.48 and 6.42, respectively, but lower pH values were reached in soil amended with less biodegradable or resistant OAs (ROAs) (i.e. blended poultry litter, biochar, and compost). At 150 % FC, the two straws increased the soil pHW to only 5.93 and 5.75, respectively, possibly due to slower decomposition under submerged conditions, resulting in limited alkalinity production, whereas amendment with ROAs produced pHW values close to 6.5. With an increasing lime-equivalent value (LEV) of the OA, from 5.8 g CaCO3 kg−1 (wheat straw) to 179 g CaCO3 kg−1 (compost), the lime requirement to reach pHW 6.5 in lime–OA combinations decreased from 2.72 to 0.09 g CaCO3 kg−1. The developed method was shown to be effective in determining the appropriate rates of OAs (with or without additional lime) for the management of acidic sandy loam soils in this study and highlights the importance of the soil water content with respect to its acid-neutralising effect.

Biochar from poultry litter as reinforcement used in epoxy-based composites: mechanical and dynamic mechanical properties

Biochar from poultry litter as reinforcement used in epoxy-based composites: mechanical and dynamic mechanical properties

Fate of antibiotics and hormones during hydrothermal carbonization of poultry litter: degradation kinetics and toxicity assessment of filtrates and hydrochars

This study investigated degradation kinetics of five selected organic micropollutants (OMPs) present in poultry litter (namely: sulfadiazine, tetracycline, and doxycycline hyclate (antibiotics); estrone and 17-β-estradiol (hormones)) during hydrothermal carbonization (HTC) treatment as the temperature stepwise increased to 250 °C. All five pure OMPs were completely degraded before 250 °C was reached during the HTC process. Nevertheless, presence of poultry litter slowed down the degradation of OMPs. Through elemental mass balance calculation, it is noted that after 15 min (temperature less than 137 °C), 69–82% of organic carbon and 50–66% of organic nitrogen initially consisting part of the target antibiotics were fully mineralized. Both HTC filtrates and hydrochars obtained from poultry litter inhibited Escherichia coli and Bacillus subtilis growth. A combination of high salinity, high nutrients, dissolved organic carbon, and other ions in the filtrate as well as the adsorption of OMPs on hydrochars were probably the reason for the high toxicity.

Hazards Associated with the Combined Application of Fungicides and Poultry Litter in Agricultural Areas.

In recent decades, the poultry farming industry has assumed a pivotal role in meeting the global demand for affordable animal proteins. While poultry farming makes a substantial contribution to food security and nutrition, it also presents environmental and public health challenges. The use of poultry litter as fertilizer for agricultural soils raises concerns about the transfer of pathogens and drug-resistant microorganisms from poultry farms to crop production areas. On the other hand, according to the Food and Agriculture Organization of the United Nations (FAO), fungicides represent the second most used chemical group in agricultural practices. In this context, agricultural soils receive the application of both poultry litter as a fertilizer and fungicides used in agricultural production. This practice can result in fungal contamination of the soil and the development of antifungal resistance. This article explores the necessity of monitoring antifungal resistance, particularly in food production areas with co-application of poultry litter and fungicides. It also highlights the role of fungi in ecosystems, decomposition, and mutualistic plant associations. We call for interdisciplinary research to comprehensively understand fungal resistance to fungicides in the environment. This approach seeks to promote sustainability in the realms of human health, agriculture, and the environment, aligning seamlessly with the One Health concept.

Biogas Dynamics and Microbial Composition Employing Different Inocula and Substrates in Continuous Stirred-Tank Reactors

The current investigation delved into the utilization of cattle and municipal sanitary inocula for anaerobic digestion of poultry wastes, addressing a crucial and pragmatic challenge in waste management. The emphasis on poultry waste is pertinent due to its well-documented impediments in anaerobic digestion, attributed to heightened levels of ammonia and volatile fatty acids (VFAs). The strategic selection of cattle and municipal sanitary inocula suggests an approach aimed at bolstering the anaerobic digestion process. In this study, we evaluated the use of cattle and municipal sanitary inocula for the anaerobic digestion of various poultry wastes, which is often challenged by high levels of ammonia and volatile fatty acids (VFAs). The substrates tested included belt waste (Poultry A), poultry litter plus feed residues (Poultry B), tray hatchery ©, and stillage. These substrates were processed in two continuous stirred tank reactors (CSTRs), R-1 (with antibiotic monensin) and R-2 (without monensin). Initially, both reactors operated with the same hydraulic retention time (HRT), using a substrate ratio of stillage: belt: tray hatchery (S:B:T) of 70:15:15. On the 41st day, the HRT was adjusted to 20 days, and the substrate ratio was changed to S:A:T 70:40:40. The specific methane yield for R-1 started at 10.768 L g−1 COD, but decreased to 2.65 L g−1 COD by the end of the experiment. For R-2, the specific methane yield varied between 0.45 L g−1 COD and 0.243 L g−1 COD. Microbial composition in the reactors changed over time. In R-1, bacteroides were consistently dominant, while firmicutes were less abundant compared to R-2. Proteobacteria were initially low in abundance, but spirochetes were found in both reactors throughout the experiment. The study concluded that Poultry B substrates, due to their rich nutrient and trace element composition, are suitable for biogas plants. Municipal sanitary inocula also showed promise due to their resilience in high ammonia concentrations. Further research into biofilm interactions is recommended to better understand microbial responses to high ammonia concentrations, which can lead to propionate production in anaerobic digestion (AD).

Effects of Acacia mearnsii tannins on growth performance, footpad dermatitis, nutrient digestibility, intestinal permeability, and meat quality of broiler chickens

An experiment was conducted to evaluate the effects of increasing dietary supplementation of tannins from Acacia mearnsii on broiler growth performance, footpad dermatitis, litter moisture, and ileal digestibility as well as on intestinal permeability, jejunal morphometric, and lipid oxidation measurements. A total of 1620 Cobb 500 one-day-old male chicks were fed 6 experimental diets with 10 replicate pens of 27 birds each in a 4-phase feeding program. Dietary treatments were as follow: non-challenged control, challenged control, and challenged supplemented with 300, 500, 700, or 900 mg/kg tannin from Acacia mearnsii. All birds on challenged groups were challenged with Eimeria spp. on day 1 and Clostridium perfringens on days 11, 12, and 13. Performance was evaluated weekly until day 43. On day 21, blood samples were collected for biochemistry analyses and the intestinal permeability was evaluated using FITC-d as marker. Ileal digestibility and jejunal morphometric were also determined on day 21. Footpad dermatitis, litter moisture, and litter pH were evaluated on days 28, 35, and 43. On day 44, carcass and commercial cuts weights were evaluated and thigh samples were collected for lipid oxidation (TBARS) through a 6 months storage period. Broilers under intestinal challenge had lower growth performance, higher intestinal permeability, and lower serum albumin, cholesterol, glucose, and triglycerides compared to non-challenged birds (P < 0.05). From day 1 to 43, increasing tannin supplementation for broilers under intestinal challenge led to quadratic increases (P < 0.05) in body weight gain, with optimal supplementation at 310 mg/kg as well as optimized estimations for feed conversion ratio at 444 mg/kg tannin. Dietary tannin supplementation that reduced intestinal permeability at 21 days was 466 mg/kg (P < 0.05). Tannin supplementation that improved protein and energy digestibility were at 374 and 294 mg/kg, respectively (P < 0.05). No effects of tannin were observed on blood biochemistry, crypt depth, litter pH, carcass measurements, and lipid oxidation until the storage day 60. However, increasing levels of tannin supplementation led to a linear (P < 0.05) decrease on lipid oxidation of broiler meat after 90 days of storage. In conclusion, low levels of supplemental tannins from Acacia mearnsii improved growth performance, nutrient digestibility, and intestinal permeability in broilers under an intestinal challenge.