Birds are homeothermic animals, that is, they control their temperature through physiological and behavioral changes such as decreased feed consumption, decreased movement, competition for space, among others. Stress in birds can lead to reduced production performance, illness and even death of the animals, which is why ensuring their well-being is of paramount importance.
Ambience is one of the most important factors for bird performance, as it directly affects their physiology, behavior and health. It is known that ambience and well-being[1] are important aspects for poultry production, being one of the requirements for commercialization in several international markets. Climate variations represent a challenge in maintaining production, especially in Brazil, due to high temperature variations.
Economic heat losses related to animal production highlight the need to minimize its impact. High temperatures can harm food consumption, increase feed conversion, reduce egg production (including decreased eggshell weight and thickness), in addition to causing thermal stress and, consequently, increasing bird mortality.
The environmental challenges in poultry farming are related to the diversity of existing production systems, which range from conventional ones, with a low level of technology and environmental control, to automated ones, with a high degree of sophistication and monitoring of environmental variables. Each system has its specifications and demands, which must be considered when planning and managing the poultry environment.
Types of aviary
Poultry houses can be classified according to the production system, which can be:
Cut: raised for meat production.
Laying: bred for egg production.
Types of ventilation
Ventilation is one of the most important factors in the poultry environment, as it is responsible for air exchange inside the poultry house. Adequate ventilation helps maintain temperature, humidity and air quality within parameters suitable for the well-being of birds. The types of ventilation can be classified according to the air movement mechanism:
• Natural ventilation: provided by openings in the aviary structure, such as curtains.
• Mechanical ventilation: carried out by fans, inlets, cooling plates and exhaust fans.
Natural ventilation is the most common type of ventilation in poultry houses, as it is more economical and easy to install, however, natural ventilation may be insufficient to meet the needs of birds in extreme climates. Mechanical ventilation is the most efficient type of ventilation to ensure adequate environmental conditions for birds, regardless of the weather. However, mechanical ventilation requires greater investment and joint operation between the operator and the birds' needs.
Ventilation in summer vs winter
Birds' ventilation needs vary depending on air temperature and humidity. In summer, birds need more ventilation to dissipate heat. In winter, birds need less ventilation to avoid heat loss, but enough to exchange gases present inside the aviary. The ideal values for ambient temperature and air humidity for birds vary according to age and production system, however, in general, the recommended values are:
These are just general values and may vary depending on other factors, such as the chicken's genetics, location and the specific conditions of each farm. It is always important to monitor the birds' behavior to ensure they are comfortable and healthy.
Impacts on animal performance
Inadequate environmental conditions can have several negative impacts on broiler performance, including reduced weight gain, reduced egg production and increased mortality. The conditions that most affect birds are:
1. Temperature: Inadequate temperature can cause heat stress in birds, which can lead to slower growth and reduced egg production. Birds tend to eat less in extreme temperatures to avoid producing excessive metabolic heat, resulting in less weight gain.
2. Humidity: Inadequate relative humidity can affect the rate of water evaporation from the bird's body, which can lead to heat stress. Furthermore, high humidity levels can promote the growth of pathogens in the breeding environment, increasing mortality.
3. Ventilation: Inadequate ventilation can lead to the accumulation of harmful gases, such as ammonia, which can adversely affect the health of birds and consequently their performance, including egg production and mortality rate.
4. Lighting: Inadequate lighting can affect bird behavior, including their feeding and sleeping patterns, which can affect their growth, egg production and mortality rate.
5. Density of A
Stocking: A high housing density can lead to stress, competition for resources and the spread of disease, all of which can negatively affect weight gain, egg production and mortality rate.
Therefore, it is crucial that poultry producers maintain adequate environmental conditions to ensure optimal bird performance. This includes regularly monitoring and adjusting environmental conditions, as well as implementing appropriate management practices to minimize stress on birds and promote their welfare.
Equipment that helps with environmental control
Environmental control in poultry houses is crucial to guarantee the health and performance of birds. There are several pieces of equipment that can be used to assist with this control:
1. Thermometers and Hygrometers: these instruments are used to monitor the temperature and humidity of the environment, respectively. They provide essential data that can be used to adjust environmental conditions as needed.
2. Fans: are used to control ventilation inside the poultry house. They help remove excessive heat by circulating air inside the house.
3. Exhaust fans: they are essential to maintain adequate air quality, temperature and humidity inside the poultry house. Their function is to control temperature, remove harmful gases, control humidity and promote air circulation within the poultry house, ensuring that fresh air is distributed evenly.
The Avifan 57" exhaust fans, developed in highly resistant polymer, provide less noise during operation, which leads to less stress on the birds. They are also able to deliver a high air flow rate that culminates in greater energy efficiency, reducing production costs, improving air quality and animal well-being. The structure of the extractor fan is manufactured from NBR 7008 CZ-275 galvanized sheet metal and high-resistance polymer, along with a sealing system made using wings made from ACM (aluminum and polymer ) of high resistance, with anti-UV protection, ensuring greater durability of the product.
4. Heaters/Ovens: in colder climates, heaters can be used to maintain the ideal temperature inside the poultry house. They can be of various types, such as gas heaters, electric heaters or models that use wood, pellets, chips, among others.
5. Nebulizers or Evaporative Coolers: These equipment are used to control humidity and temperature, especially in hot climates. They work by evaporating water, which cools the air and increases humidity.
6. Lighting Systems: Adequate lighting is crucial to bird behavior and performance. Lighting systems can be adjusted to provide the appropriate quantity and quality of light throughout the growing season.
7. Automated Feeding and Drinking Systems: Although not directly related to environmental control, these systems can help reduce bird stress by ensuring that they have constant access to food and water.
All of this equipment, when used correctly, can help create an ideal environment for birds, thus improving their performance and well-being.
The search for a better environment in poultry production systems aims not only to improve the well-being and performance of birds, but also to reduce production costs and the environmental impacts of the activity. Saving electricity and water, reducing gas and dust emissions and improving the quality of the final product are some of the benefits that can be obtained with an appropriate environment. The choice of equipment must be made according to specific needs and is a fundamental factor in ensuring adequate environmental conditions, and it is always important to know the birds' needs and the aviary model.
In addition to good equipment, it is essential to invest in training the workforce involved in poultry farming, who must be highly specialized to deal with new technologies and environmental challenges. Constant updating of professionals is essential to guarantee the quality and competitiveness of Brazilian poultry farming in the global market.
BIBLIOGRAPHIC REFERENCES
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