Following up on my last column on better pig house insulation, I continue this mini-series concerning key and basic profit-dependent areas of pig production - with more to come.
Some of you may think you know it all, but in my experience of solving problems on pig farms - even today - many don't, so refresher courses may be in order.
Ventilation basics: a refresher
A discussion of ventilation back in the farm kitchen can open eyes, and with better understanding, the remedies seem more feasible; the response is "I never realized that was the cause.
"Why do we ventilate?
In order to provide oxygen,
Controlling the temperature;
Moisture, excess heat, gases, dust, bacteria, viruses, fungal spores, and chemicals are removed.
Ensure the health and happiness of pigs and stockpeople.
Extending the life of a building.
However, it is too simplistic
As a result, we need to keep the pigs in their environmentally-influenced comfort zones for economic reasons. To achieve this, we need to:
For maximum performance, we should provide a varying air supply in normal temperature conditions;
It is recommended to maintain the temperature around the pigs within 3 to 4°C of the outside temperature during temperate summers;
High air speed can be provided over the pigs in very hot conditions to increase their upper temperature tolerance level, often aided by wetting;
In cold to very cold conditions, provide a controllable minimum level of ventilation, while directing the air adequately over the pigs with good air mixing, so as to avoid draughts from cold incoming air. This process may be assisted by supplementary heating.
When pigs are kept warmer in cold weather than sufficiently cool in hot weather, the effect of exceeding the animal's Upper Critical Temperature is to lower performance. Visit our website to get more info about exhaust fan for pig farm.
Underrated and undervalued
I have found that clients are much better at keeping pigs warm than at keeping them cool enough for years. In the former, they are alert to huddling, shivering, compensatory over-eating, but less aware of hot weather signs of wrong-mucking, especially if they occur in central pens rather than in pens at either end of the building.
A greater incidence of tail biting and other disturbance vices, along with a drop-off in appetite, which, even if slight, can still adversely affect performance – especially with their several months of backlog – affect their performance. When clients are told that incorrect ventilation is the most likely cause of their concerns, they are surprised.
How do ventilation rules work?
As air moves, it does not move straight, unless it is under high pressure, but rather in 'bubbles' that swirl up and down (warm air rises), becoming less as distance increases. In normal temperatures, air must be manipulated so that it crosses the pig's back at about 0.2 m/s.
To judge this air flow, you will need a smoke generator, such as that used by beekeepers.
Pigs are normally ventilated last, the dunging area first. In hot weather, the reverse is true.
Additionally, have long air travel to ensure the pigs are never exposed to a cold air current or draught. In hot weather, reverse the process. Read more: www.pigequipments.com
It is the controllable inlets that direct the air. Therefore, the inlet closure and fan speed must be interconnected by a controller.
Exhaust the air, not pressurize, as a fan exhausting the air in a properly sealed building must draw air in from the inlets which can be controlled. Determine the amount of air the pigs require according to their weight and number.