Environmental Impacts of the Brazilian Egg Industry: Life Cycle Assessment of the Battery Cage Production System.

Brazil stands as one of the world's leading producers of animal protein, ranking sixth in global egg production. However, estimated growth in production demand, along with environmental impacts, represents a potential threat to the sustainability of the food system. Methods for assessing and quantifying the environmental impacts generated by Brazilian egg production remain scarce, lacking current reports on comparative effects or guiding standards. The objective of this study was to conduct a life cycle assessment from cradle to farm gate, adhering to ISO 14040 and 14044 standards, for the battery cage egg production systems and associated products in Brazil, with the aim of supporting and promoting sustainability improvements in the Brazilian egg industry. The entire life cycle modeling and process sustainability analysis were executed using the openLCA software, integrated with the Ecoinvent database. Emissions related to egg production yielded results of 65.06 kg SO2 eq., 27.74 kg N eq., 3086.71 kg CO2 eq., 75,152.66 CTUe, 2.75 × 10-5 CFC-11 eq., and 10,044.68 kg MJ eq. per ton of eggs produced. These findings can serve as comparative benchmarks for future studies and for analyzing data across different egg production systems in Brazil.

Life Cycle Assessment Project for the Brazilian Egg Industry.

Brazil is among the ten largest egg producers in the world. The domestic consumption of Brazilian eggs is 99.6%, the rest being exported to more than 82 countries, with an expectation of growth in the foreign market. The Brazilian egg industry has evolved considerably in recent decades, incorporating new technologies and smart practices. However, there is no assessment of how production could become more sustainable over the years. The LCA (Life Cycle Assessment) approach aims to recognize the polluting potential, identify the environmental impacts generated and reduce these impacts throughout production. On a global scale, researchers approach LCA as a constructive and quantitative technique, and there is great interest in implementing an LCA for the Brazilian egg production sector. With the aim of introducing the LCA methodology to the Brazilian egg industry, this review presents the concept and accounting structure of LCA through LCI (Life Cycle Inventory) and LCIA (Life Cycle Impact Assessment), based on the ISO 14040 and 14044:2006 standards, to quantify the environmental performance of production and identify areas for future improvement, thus promoting the environmental footprint of the Brazilian egg industry.

Spatial Distribution of Bedding Attributes in an Open Compost-Bedded Pack Barn System with Positive Pressure Ventilation in Brazilian Winter Conditions.

The objective of this study was to characterize the dependence and spatial distribution of bedding attributes in an open compost-bedded pack barn (CBP) system with positive pressure ventilation during the winter period in Brazil. The study was conducted in July 2021, in the Zona da Mata region, Minas Gerais, Brazil. The bedding area (shavings and wood sawdust) was divided into a mesh with 44 equidistant points. At each point, the bedding temperature at the surface (tB-sur) and at a depth of 0.2 m (tB-20) and the air velocity at bedding level (vair,B) were measured, and bedding samples were collected. The bedding samples were used to determine the moisture level and pH at the surface (MB-sur e pHB-sur) and at a depth of 0.2 m (MB-20 and pHB-20). The spatial behavior of the variables was evaluated using geostatistics techniques. For all variables, the occurrence of strong spatial dependence was verified. Through the maps, it was observed that tB-sur, tB-20, MB-sur, MB-20, and vair,B showed high spatial variability, whereas pHB-sur and pHB-20 demonstrated low variation. On the surface, values of tB-sur < 20 °C and MB-sur > 60% were observed. At the subsurface, there was a predominance of tB-20 < 40 °C, MB-20 > 60%, and pH > 9, which are indications of low bedding composting activity.

Potential for Ammonia Generation and Emission in Broiler Production Facilities in Brazil.

Air quality is one of the main factors that must be guaranteed in animal production. However, the measurement of pollutants is still a problem in several countries because the available methods are costly and do not always apply to the reality of the constructive typology adopted, as in countries with a hot climate, which adopt predominantly open facilities. Thus, the objective of the present study was to develop predictive models for the potential generation and emission of ammonia in the production of broiler chickens with different types of litter, different reuse cycles and under different climatic conditions. Samples of poultry litter from thirty commercial aviaries submitted to different air temperatures were analyzed. The experiment was conducted and analyzed in a completely randomized design, following a factorial scheme. Models were developed to predict the potential for generation and emission of ammonia, which can be applied in facilities with ambient conditions of air temperature between 25 and 40 °C and with wood shaving bed with up to four reuse cycles and coffee husks bed with up to six reuse cycles. The developed and validated models showed high accuracy indicating that they can be used to estimate the potential for ammonia generation and emission.

Spatial Variability of External Egg Quality in Vertical Naturally Ventilated Caged Aviaries.

External egg quality is an essential parameter of egg production as it relates directly to economic losses. This study evaluated the spatial variability of external egg quality in five naturally ventilated caged vertical aviaries. Differences caused by bird age and thermal and luminous variability within aviaries during winter and summer were analyzed. Data on aviary air temperature, relative humidity, light intensity, and external egg quality were collected at evenly distributed points along the aviary length within three levels of cages. The experimental design was completely randomized in a factorial scheme. In the summer, the highest air temperature and lowest relative humidity were found in central cages, mainly in upper center cages; hens produced eggs with a lower weight and shape index in this area. Similar results were obtained in the winter. In the summer, eggs with lower shell weight and thickness were also produced by hens housed in the central cages, but in the winter, the opposite result was obtained. This study of the spatial variability of external egg quality proved efficient in detecting areas within an aviary with poor quality eggs; improvements to design and management in these areas could help management improve production efficiency and contribute to a sustainable egg supply.

Mapping of the Thermal Microenvironment for Dairy Cows in an Open Compost-Bedded Pack Barn System with Positive-Pressure Ventilation.

The objective of this study was to evaluate and characterize the dependence and the spatial and temporal distribution of variables and indices of the thermal environment in an open compost-bedded pack barn system with positive-pressure ventilation (CBPPV) during the winter period. The study was conducted in a CBPPV system located in the Zona da Mata region, Minas Gerais, Brazil. The indoor environment was divided into a mesh composed of 55 equidistant points, where data on dry-bulb air temperature (tdb) and relative humidity (RH) were collected. The collected data were divided into four periods-dawn, morning, afternoon, and night-and mean values were obtained. To evaluate the thermal microenvironment, the temperature and humidity index (THI) and the specific enthalpy of air (h) were used. For spatial dependence analysis, geostatistical techniques were applied. Through the results, a strong spatial dependence was verified for all variables evaluated. Through THI and h maps, conditions of thermal comfort were found for dairy cattle. The highest values of tdb, THI, and h were recorded in the afternoon period in the northwest region of the facility (tdb = 23.2 °C, THI = 69.7, and h = 50.9 kJ∙kg of dry air-1).

Spatial distribution of bed variables, animal welfare indicators, and milk production in a closed compost-bedded pack barn with a negative tunnel ventilation system.

This research aimed to characterize, evaluate and compare the spatial distribution of the leading bed variables, animal welfare indicators, and milk production in a closed compost-bedded pack barn (CBP) with a negative tunnel ventilation system, for summer and winter periods. The study was carried out in a CBP located in the Zona da Mata region, Minas Gerais, Brazil. The geostatistical modeling technique evaluated the variables of temperature, moisture content, and pH (on the surface and depth of 0.20m) across the length of the bed. Bed samples were characterized for carbon (C), nitrogen (N), and C:N ratio. Cows housed in the CBP were assessed for locomotion and hygiene scores and average milk production. To evaluate the thermoregulation of the cows, the respiratory rate (RR) and surface temperature (ST) were measured. Geostatistical analysis showed spatial dependence and the non-uniformity of the spatial distribution of bed variables. The worst levels of bed temperature and moisture were found in the regions close to the evaporative cooling plate, surrounding the feeding alley, and in the region with the highest cow stocking. The C:N ratio, obtained in both climatic seasons of the year, remained outside the recommended range for ideal composting. During the summer and winter, the bed variables' values suggest that the material was below levels for optimal composting; however, the aerated inner layer was biologically active. The high animal density significantly impacted the worsening of the bed moisture content and internal temperature. In general, dairy cows showed adequate hygiene (score of 1 and 2) and locomotion (score of 0 and 1) scores for the two climatic seasons evaluated, indicating good welfare conditions. In relation to RR and ST, the summer period presented less favorable environmental conditions. During winter, the average milk production was 28.1 ± 7.2 kg day-1, and during summer, it was 26.9 ± 6.7 kg day-1.

Modeling and simulation of the transient response of temperature and relative humidity sensors with and without protective housing.

Based on the necessity for enclosure protection of temperature and relative humidity sensors installed in a hostile environment, a wind tunnel was used to quantify the time that the sensors take to reach equilibrium in the environmental conditions to which they are exposed. Two treatments were used: (1) sensors with polyvinyl chloride (PVC) enclosure protection, and (2) sensors with no enclosure protection. The primary objective of this study was to develop and validate a 3-D computational fluid dynamics (CFD) model for analyzing the temperature and relative humidity distribution in a wind tunnel using sensors with PVC enclosure protection and sensors with no enclosure protection. A CFD simulation model was developed to describe the temperature distribution and the physics of mass transfer related to the airflow relative humidity. The first results demonstrate the applicability of the simulation. For verification, a sensor device was successfully assembled and tested in an environment that was optimized to ensure fast change conditions. The quantification setup presented in this paper is thus considered to be adequate for testing different materials and morphologies for enclosure protection. The results show that the boundary layer flow regime has a significant impact on the heat flux distribution. The results indicate that the CFD technique is a powerful tool which provides a detailed description of the flow and temperature fields as well as the time that the relative humidity takes to reach equilibrium with the environment in which the sensors are inserted.