The provision of well-designed shade or shelter structures, particularly during hot weather, improves the wellbeing of animals in the feedlot.
In the previous Lotfeeding Journal I outlined the advantages of providing shade or shelter structures to feedlot cattle.
In this article, I look at the design and construction of shade or shelter structures. Many feedlots have already installed shade or shelter structures, with more than 69 per cent of the national feedlot capacity having access to shade.
For feedlots still investigating shade or shelter structures, several key objectives must be considered in the design and construction process:
Adequate Coverage: Ensuring each animal in the pen has sufficient shaded space.
Structural Integrity: Constructing shade structures that are both durable and structurally sound to withstand various weather conditions.
Ease of Cleaning: Minimising obstructions during pen cleaning.
Optimal Air Flow: Maximizing air circulation beneath the structure to enhance overall comfort.
Efficient Pen Drying: Designing structures to facilitate efficient pen drying, crucial for hygiene and preventing the buildup of wet manure.
Geographical Considerations: Adapting the design to suit the specific geographical location of the feedlot. Different shade or shelter structures exist, each with their own merits and considerations.
Longitudinal rows – long thin shade structures that stretch over many different pens
Centre squares – structures in the centre of the pen
Separate panels – structures connected in a grid-like pattern and providing alternating shade spots through each pen.
Covered feedlots – structures that completely cover the feedlot pen and prevent rain from falling on the pen surface.
The choice depends on factors such as structure size, orientation, height, and shading material. It is advisable for shade structures to provide more than 2 sqm of shaded pen floor space per animal, especially during heat load events when spreading cattle becomes beneficial. Both longitudinal row and centre squares shade structures may have spaces or gaps throughout the structure to encourage the pen floor to dry during the day and to increase air flow.
Sunlight reaching different parts of the pen at different times of the day helps prevent a buildup of wet manure. Orientation, height, and material selection are critical aspects of the design process.
Longitudinal row structures, for example, are ideally north-south oriented to maximise drying efficiency, while centre squares and separate panels are less sensitive to orientation. The height of shade structures influences the area of shade cast at different times of the day. Higher structures allow better ventilation but result in increased wind loads and costs. Lower structures may discourage cattle from entering the area and restrict access for pen cleaning.
A minimum height of 5m will reduce the risk of pen cleaning machinery damaging the cover with an extended loader bucket or burning holes in shade cloth with an exhaust pipe. Shade structures often use materials such as shade cloth, galvanised iron sheets, or waterproof fabrics.
ALFA and MLA have collaborated to provide comprehensive resources, including the ALFA Unlocking the Benefits of Shade handbook, MLA Feedlot covered housing systems best practice design and management manual, case studies from feedlot operators, webinar recordings and links to structure manufactures. These resources are all available on the ALFA Shade Resources Hub.
While there is a wealth of information available, feedlot operators are still encouraged to seek professional advice from structural engineers to ensure the optimal design and functionality of shade or shelter structures.