Theo Bos: My untrimmed laying hens waste less water

Theo Bos: My untrimmed laying hens waste less water

"After fourteen days, everyone has tunnel vision," layer poultry farmer Theo Bos quotes a former teacher's anecdote. Whilst building a third poultry house, he also discovered that you're never too old to learn something new. Thanks in part to a new management system, he noticed that the water usage in his two new laying houses was 0.1 ml per gram of feed lower than in the old housing. 
"Water wastage results in wet manure on the manure belt, and every poultry farmer knows wet manure costs money." 

"Tap, tap, tap, tap. A hen drinking. To me, that's the most beautiful sound there is at the start of a new cycle", says Theo Bos as he opens the door to the laying house. The untrimmed laying hens effortlessly push the nipple to drink. 

Bos' new barn, equipped by Jansen Poultry Equipment, provides space for 18,000 NOVOgen Brown Classic hens. He keeps the birds according to the Dutch requirements under the highest-rated conditions (3-star Better Life). 

The second house underwent a complete renovation in 2016. It now houses 14,000 laying hens, also under a 3-star Better Life quality label rating. The renovation took place one year after Bos switched to untrimmed laying hens. 

The ideal drinking nipple for untrimmed laying hens

Because of their longer upper beak, untrimmed laying hens can no longer approach the drinking nipple from below. That's why they peck at the nipple with the side of their beak. But when drinking from a 180-degree or traditional 360-degree drinking nipple, they waste quite a lot of water. Therefore, a 360-degree nipple with a low side-action flow rate is more suitable for untrimmed laying hens, just like the I-Flex 14-SP drinking nipples installed at the farm of Theo Bos. These drinking nipples are specially designed for untrimmed laying hens. 

There is less water wastage in the new houses

He believes the advantages of the new drinking nipples are evident in the water/feed ratio between the newest and the oldest housing. In the oldest house, built in 2010, he keeps 34,000 hens under a Better Life 2-star rating. "With the new housing, we switched to a new management system, which makes the contrasts between the three houses even more obvious. The two different screens presented us with a clear outcome. In the 2010 housing, the water/feed ratio is 1.8 per hen, while in the other two newer houses where we use the specially designed drinking nipples, the water/feed ratio is 1.7.

Every poultry farmer knows wet manure costs money.

The birds use 0.1 ml less water per gram of feed, which shows that the hens in the oldest house waste more water. 
Untrimmed laying hens do have a different way of drinking. Ultimately, the water wastage results in wet manure. Fortunately, we don't encounter health problems or pecking. They just make a mess. Thanks to the simulation, we now know that they do a lot less with the new drinking nipples.

Adjusting the water pressure may reduce water wastage

The 2010 housing happens to be empty for a few weeks due to maintenance. During this period, Jansen Poultry Equipment will also replace the worn pressure regulators, which are outdated. "We discovered that they needed to be replaced too. The pressure was too high, which, of course, also results in additional water wastage. So we want to wait and see what comes of that before we invest in new drinking nipples for this housing. We are going to play with the pressure first, which may go a long way to resolving things." The main water supply pipes run in all three houses to the two pressure regulators, mounted in the middle of each drinking line.

Do you want to know the ideal water pressure for your laying hens? Check it here!

"We are going to play with the water pressure, which may go a long way to resolve things."

A higher water capacity to meet the needs of the hens

In the new house, we installed a height-adjustable drinking line. The drinking line has a diameter of 28 mm, which is wider than the standard 22 mm diameter. 

A 28 mm drinking line has a higher water capacity, so more water is available over the entire length. This is especially important in the morning when a lot of hens drink water at the same time. "We leave the drinking lines hanging at a fixed height because the birds are over seventeen weeks old. They won't get any bigger anymore and can easily reach the drinking nipples." 

Maximizing egg production

Back in 1993, the 'De Peppel' farm had chickens, cows, and pigs. In 2010, Theo Bos stopped with dairy cattle and constructed housing for 41,500 laying hens. In 2016, the second house underwent a renovation and was adapted for 14,000 chickens. "Actually, I prepared the house for organic housing; I did that for three rounds but then stopped as it didn't really suit me." 

In the third house completed last year, Bos used the space left according to his permit. "I reduced the number of chickens in the 2010 housing to 34,000. By doing this, I now meet the living space requirements for when it is no longer allowed to include the covered wintergarten." 

The average egg production is 385 to 390 eggs per hen. "The goal is to reach four hundred eggs, especially by playing with nutrition. For example, we currently already add oyster shell grit as a source of calcium to the diet at the end of the round, to improve the eggshell quality." 

Everything starts with water

Everything the hen needs, Bos adds through the feed. He is reluctant to administer medicines through the drinking line because the water comes from a natural spring. Bos obtains the NOVOgen chickens from Verbeek Hatchery Holland.

"We don't have specific requirements, but we do want hens that are used to drinking from drinking nipples, so they know how to find the water, and the start-up will go as easy as possible. My opinion is that everything starts with water." 

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