Litter quality is such an important part of the net profit factor in today's broiler chicken industry that it needs maximum attention. There are many reasons why litter becomes too wet and answers how to keep litter dry. World Poultry dives into litter management.
By Ken Marshall
After hatching, when the chicks are placed in the growing house the most important aspect after house temperature and correct feed and water availability, is litter management, keeping the litter dry. Basically, one must know, when litter is "Wet". What constitutes wet litter? Better still, let's define it as, 'A physical state in which the bedding contains too much moisture'.
How much is too much? 20-25% moisture is considered good. 26-39% will give problems and cost you losses and 40+% is really a disaster. One usually sees the first signs of moisture underneath the nipple lines and it spreads out from there. Even before it reaches the 20% level one can see a damp wet slippery surface on the top of the litter and shortly afterwards a crust beginning to form. This occurs basically due to poor levels of management, not only by the stockman as there are other factors beyond his control that can also contribute to what is happening.
What can be done?
The type of litter (bedding) used is very important. Globally, a soft white wood shaving is preferred, the red woods are harder and do not absorb as much moisture as the mostly pine white wood shavings do. However, the red wood may, in some instances, be better than other types of bedding that is used. It is not by chance that you are able to get a supply of the best, when planning a new venture, it requires you to know everything about the procurement of all your main imputs.
Other types of bedding
Sunflower seed husks can usually be obtained from a feed mill, as they are predominately a black colour and there is a tendency to make the floor of the house dark, so be careful, you will need to add extra lighting in the brooding area (bigger or brighter globes and more of them). Ground nut kernels (peanuts) can also be used, however they may not be the best for chicks' feet and their moisture retention is not very good. They can also be prone to having fungi if stored incorrectly. If you cannot get anything else, use it. Chopped straw, (in an emergency only scenario - use in the brooding area until your delivery of better bedding arrives).
Litter is wet when its moisture level is in the region of 40+%. It is significant, regardless of the type of housing, closed environment, or open type natural ventilation using a curtain system or even the type of drinking system to a large extent. Management practices of the chicks, from day old, also plays an important part. These will be discussed later. We must remember that a chicken over its normal 35 day growth cycle consumes up to twice as much water as it does feed.
Assuming a 35 day live weight of 2.1 kg at a FCR of 1.55 = 3.255 kg feed (3255 gm) @ 1.75 x more water than feed = 5696 ml or cc or 5.696 litres of water/bird. At 2.0 x more water than feed = 6510 cc water = or 6.5 litres. In many instances the litter is wet by 14 days when the chick weighs only 480-500 gm and has consumed 500 gm of feed and @ 1.75 x more water = 0.5 x 1,75 = 875 gm feed 0r (0.875) L of water. @ x 2.0 = 1000 ml or 1.0 litres.
Why is this happening in so many instances that the litter is wet at 14 days? Indication would have it that possibly better management has not kept pace with increases in bird performances on many poultry farms. Many houses that were erected 10+ years ago are still using the same bird numbers today, however with the genetic advancement alone (not to mention better nutrition), in hatchery vaccinations, gut health promoters, water soluble stress reduction packages to administer after water vaccinations and feed phase changes. Live weight/m2 has most probably increased by around 20+%.
There are several factors to take into consideration: Stocking density, type of drinker (nipple), has it got a drip cup? Experiences show that it may not be necessary, however there are pros and cons and it is up to the company or farmer to decide what he is happy with. Start without and add later if necessary.
Water line pressure - are the adjustments correct to give the required nipple flow rate for the birds requirements or is the pressure too high? Birds soon learn not to eat so much if there is not enough water available. If there is no water available they will soon stop eating. Spend some time in your chicken houses, not just a quick walk through and say "that looks ok." Take a small fold up camping seat, sit down and watch the chicks/birds. How are they behaving - are they comfortable walking on the bedding that has been provided? How does the air flow appear to you? Take out your air flow meter and measure it just above bird height. Depending on whether it is a Tunnel system or a cross flow, take more measurements closer to the air exit points and also temperatures with an IR (infra red laser) thermometer. Also at the air inlets. Ammonia readings as well as C02 should also be taken on a regular basis especially when there are seasonal changes, as adjustments may need to be made. If you get into this habit on a regular basis it will pay good dividends. Maybe the bedding is too hard or sore for the chicks' feet, maybe they are not active enough because of this or are the house temperatures correct? Is the floor temperature on top of the bedding at day old 32˚C and a house temperature of 34-35˚C?
Listen to the chicks
In this fast moving industry you only have 35 days and if an error is made in the first few days it can be difficult if not impossible to catch up! Listen to what the chicks are telling you! Are they too hot or cold or just right? How is their drinking behaviour? Are they getting enough water (time spent at the nipples) - check by pushing some nipples at the front middle and end of each line. Better to purchase a water meter stick, to measure the flow rate per minute along the line. This should be done 4 times daily and written where it is close to the water lines along the inside front of the house. Use the long standing formula: Multiply 7ml per minute, times the age in weeks and add 20, i.e. 7 x 3wks = 21 + 20 = 41 ml per minute. These stats were applicable 10+ years ago and as bird weights have increased over that period by 10+%. Addition may need to be made! Check with your breed supplier for his recommendations for your area and type of house, as well as the manufacturer of the drinking equipment.
Monitor with the right equipment
In order to have your flock at optimum environmental conditions you will need some additional equipment to help you, especially if you do not have a CE house. Even if the house environmental computer gives these stats. Ammonia meter, CO2 meter, hygrometer for % RH as well as a wind speed measurer in meters per second. In order to measure the % moisture in the litter one needs a unit somewhat like a hand held infrared thermometer (which you also need) and this can give you an instant reading for the surface moisture %, you will also need to remove litter to create an opening (a small gardening four-pronged fork) and take more readings of the litter below the surface. Wet litter is classed at +- 35-40% moisture. However, you should aim not to be above 20%. The old yardage of measurement to give a rough idea is to squeeze the litter in your hands and estimating, if litter clumps and stays in a ball, it is too wet. If litter instantly dissolves and falls in fine particles, it is too dry. If the litter initially clumps and then starts to disintegrate it is probably ok at 20-25% moisture.
With poultry there is too much involved to play guessing games - the cost is minimal and you need to know exactly what is happening! Your results will show you what you have to do. If you do not have the correct tools then you are making things more difficult for yourself and your staff.
Source: World Poultry, Volume 30, no. 9, 2014
The second part of this article can be found here...