Energy Consumption Evaluation in Dark House Aviaries, With and Without Thermal Insulation: A Case Study in the Western Region of the State of Paraná

Broilers production suffered, due to major investments in technology and genetic development in recent decades, to adapt to the conditions and requirements of the national and world market. Studies on the production systems of reraring show the importance of the economy in the sector, which is one of the most competitive in the agribusiness sector. The present work aimed at studying two dark house aviaries construction, with and without thermal insulation, to evaluate the variations in temperature, gas consumption, and effect of the insulation. Both facilities were checked for temperature variation, using J-type thermocouple sensors and recording in datalogger; LPG consumption, and the production performance considering mortality of birds, feed consumption, water intake, and weight gain. It was concluded that the Dark House with Thermal Insulation (DHTI) aviary showed better broiler birds performance indexes, lower mortality, and greater weight gain. But when it comes to performance in the face of temperature conditions, the Conventional Dark House (CDH) aviary showed values better suited to the production, as noted in the bibliographic references.


Introduction
Technological advances in Brazilian poultry industry in recent decades have been decisive for the segment to consolidate itself as one of the most competitive in the agro-industrial sector. Brazilian poultry industry ranked first in the world in exports and second in broiler production-a placement that guarantees about 9% of the country's exports, generating more than two million direct and indirect jobs according to the Brazilian Animal Protein Association-ABPA (2019), in 2018. In 2018 alone, Brazil exported a total volume of 4,101 million tons of chicken meat, amounting to US $ 6.571 billion. The state of Paraná produced about 4.56 million tons of chicken meat, representing around 35.47% of chicken meat in the country. The total national production of chicken meat reached 12.86 million tons in 2018.
Genetic improvements; investments in technology; and care for health, nutrition, environment, and better quality of management justify this lead and potential. The environment plays an important role on production, as an inadequate environment leads to a drop in production and meat quality, consequently incurres losses to the producer (Souza, 2005).
With advancement of time, the environment and the equipment for the poultry production undergo changes, and the same is true for suitable aviaries for the birds, especially in terms of thermal control and easy handling. Thus, aviaries have been adapting and modernizing with the use of equipment and systems that provide better automation and production control, such as the use of exhausters, heating systems, evaporative panels and air jas.ccsenet. and tempe identified which allo Nonethele handling a United Sta broilers is increase in The challe handling a of energy, environme In this con terms of m convention

Method
The presen in the extr South, Lo (1948)

Measuring Instruments and Systems
The evaluation of the energy consumption of the two aviaries was carried out based on their thermal control system, both inside and outside, during the period of production of the birds, where the following data were verified: air temperature and gas consumption.

Air Temperature
The air temperature was checked inside and outside the aviaries. In the external area, a sensor was installed, equidistant between the aviaries, for the continuous measurement of air temperature throughout the experiment.
In the internal area, in order to characterize the level of thermal comfort, the air temperature was verified through the installation of temperature sensors. To check the temperature, Switerm's Type J Thermocouples SMTJ 8 mm were used, consisting of two distinct metallic conductors, according to the specifications in Table 1. Three internal sensors were used in each aviary to determine the average temperature, one being 6 meters long and two 12 meters long, due to the distance from the measurement point to the temperature recorder. To store data and record air temperature measurements, a MasterLogger A 202 Datalogger, from the manufacturer Contemp, was used, with 8 channels and technical characteristics described in Table 2. The datalogger was used to collect the voltage variation in the sensors, and the values to compare temperature difference were recorded at every 5 minutes.

LPG Consumption
For the evaluation of gas consumption, volumetric gas meters were installed in each of the evaluated aviaries, located in the secondary distribution network. The equipment used was LAO's G10 gas meter. The operating jas.ccsenet.org Journal of Agricultural Science Vol. 12, No. 5;2020 principle consists of channels between four chambers that move the diaphragms that coordinate the loading and unloading of the system, activating the rotary valve that moves the integration system.
The equipment totalizer has an is 8-digit cyclometric register, with an optical reading marking. The technical data of the equipment is shown in Table 3. The meters were installed outside the aviaries, connected to the secondary network that distributes the gas to the heaters inside the aviaries.

Broiler Birds Performance
To determine the broiler birds' performance, the most common zootechnical indexes, recorded daily, were used.

Data Analysis
For data analysis, the project was divided into two construction systems, considering the data obtained in the Conventional Dark House (CDH) aviary and in the Dark House with Thermal Insulation (DHTI) aviary, with two production periods being considered for each of the models, the initial one (broilers' initial growth period, with a period of 0 to 7 days of age, in an expandable area internal to the shed called a chicken coop, corresponding to the need for heating the birds. In this phase, it was possible to verify the gas consumption for heating) and the final one (period characterized by the growth of birds, comprising 22 to 29 days, period in which the consumption of electricity was evaluated). The results obtained were presented in the form of tables and graphs, enabling the comparison between the two systems and an analysis of the variables obtained in the birds' confinement time and their breeding phase.

Temperature
The average temperature values (ºC) verified through the sensors and registered in the datalogger are shown in Table 4. It is observed that the highest external temperature recorded was 38.1 ºC, on the first day of confinement (08/01), and the highest internal temperatures recorded were on the second day (09/01), where in the CDH aviary registered 31.4 ºC, and the DHTI aviary 35.1 ºC. In the graphical representation of Figure 3, it can be seen that the DHTI aviary temperature was higher than the CDH aviary temperature. Regarding the external temperature, the CDH aviary presented an internal temperature always lower than the external one, and on January 14, there was the smallest variation of 0.2 ºC. The DHTI aviary presented greater temperature variations, and in the period from 12/01 to 14/01, corresponding to the 1st week, and in the 3rd week (23/01 and 24/01) internal temperatures are higher than the external ones. In view of (CDH) avi for the air generating has the exh and circula f gas, .45% view of the less insulation of the sealing materials, and the greater propensity to air flows due to the less tightness of the system, promoting the removal of heat.

Broiler Birds Performance
The mortality (M) and culling (C) data of the birds confined in the two evaluated aviaries, under the effect of the two distinct construction systems, Conventional Dark House (CDH) aviary and in the Dark House with Thermal Insulation (DHTI) aviary, at the end of the evaluation period (four weeks), are shown in Table 6. Note. Dead birds (M), birds Culled (C).
It can be observed that in the Conventional Dark House (CDH) aviary there was a higher mortality rate of birds, totaling 344 birds with a standard deviation of 66, while in the Dark House with Thermal Insulation (DHTI) aviary, the total number of dead birds was 299, with a standard deviation of 27, at the end of the fourth week.
The birds culled totaled 177 in the CDH aviary and 95 birds in the DHTI on, with a standard deviation of 57 and 32, respectively.
Through the analysis of the data of the dead birds in both aviaries and of the temperature data in the first week, it is found that the temperatures in DHTI are more suitable for the birds, providing a smaller number of dead birds, which was 98, while in CDH it represented 184 dead birds. Thus, it is concluded that in the initial phase, that is, the initial growth period of broilers, from 0 to 7 days old, the DHTI aviary presents a better performance of broiler birds production, with a smaller number of dead birds.
According to the data analysis, it can be verified that in the CDH aviary there was a 33.43% higher mortality than in the DHTI one, while the percentage of birds culled in the same aviary was 46.33% higher than in the thermally insulated aviary.
Regarding the amount of feed consumed during the evaluated period, it can be observed that in the Dark House with Thermal Insulation (DHTI) aviary there was a higher feed consumption than in the CDH aviary, with 94.320 kg and 91.958 kg respectively, a difference of 2.5%.
According to the mortality and culling data, the DHTI aviary represented lower total quantities in the evaluated periods, that is, a greater number of growing birds. In view of the above, it is concluded that feed consumption was higher in the aviary, as a result of a greater number of birds in production, than in the CDH aviary.
The amount of water consumed during the production period is shown in Table 7. According to data analysis, it is observed that in the CDH aviary the water consumption was 121.260 liters and in the DHTI the total consumption was 126.597 liters, thus, it can be concluded that the DHTI aviary presented, in addition to higher feed consumption, a 4.22% higher percentage of water consumption. As the DHTI aviary had higher temperatures in the evaluated period, and a greater number of birds in the growing period, due to lower mortality and culling, it is concluded that the higher water consumption is influenced by these two variables.
Regarding the monitoring of the birds' weight gain, Table 8 shows the values obtained by weekly measurements.  Considering the difference in final weight and the initial weight of the birds, performed every seven days, it can be seen that in the Dark House with Thermal Insulation (DHTI) aviary the average weight gain was 20 grams more than in the CDH aviary, at the end of 28 days of confinement.

Comparison of Results
In Table 9, the two construction systems are compared, Conventional Dark House (CDH) and Dark House with Thermal Insulation (DHTI), allowing a general comparison of variables and broiler birds performance, verified and discussed in the present work.