Optimal Flock Size for Pasture Raised Layers

Optimal Flock Size for Pasture Raised Layers

Summary

Objectives/Performance Targets

Accomplishments/Milestones

Work Activities

In the spring of 2016, our first year of a two year project, we built a movable coop and movable nest boxes for a 100 layer flock on pasture.

Unlike the larger pasture structures, we wanted the smaller flock structures to be moved by hand, so we constructed two separate units: A mobile unit for the roosts and a mobile unit for the nests. The water was kept with the nests.

In addition to the construction materials for these, we also purchased a feeder and components for a waterer for this 100 layer flock.  We also purchased 4 movable electric nets for security against land predators and we purchased a portable electric fencer and a deep cycle battery to keep the fence electrified.

Additionally, funds were used to help offset labor costs for the additional time needed to maintain an extra flock, to construct the pasture housing, as well as for the farm tour and talks.

In late summer of 2016 we held a farm tour that highlighted the SARE project and we began working on a manual entitled “100 layers on pasture”. In January of 2017 we presented at the N. Michigan Small Farm Conference with a workshop about layer chickens on pasture.

Impacts and Contributions/Outcomes

Results and Lessons Learned

The birds went out to pasture when the fields were ready in April. We divided the flock into 3.

The two larger flocks were composed of 250 and 450 birds. For these respective flocks we utilized mobile coops that we built in previous years. The 100 layer flock used a brand new coop we built in March of 2016.

With the larger flocks, the chicken ships (what we call the pasture housing) include roosts, nests and water and are moved around by a tractor or truck. However, with the smaller flock we wanted to be able to move them by hand so we made two different structures to keep the weight to a minimum. The roosts and the nests were separated and the water was housed with the mobile nests.

The flocks were divided in April when they went out to pasture. For the first 2 ½ months they performed similarly. The 100 layer flock did lay a bit better but only by a small margin (less than 3%) and I didn’t want to draw any conclusions from this small difference.

This continued through May and into June, but by the first of July, our summer turned quite hot and dry. It was the hottest July and August we had experienced in N. Michigan and the layer’s efficiency suffered because of it. This was difficult for our farm’s finances but good for our SARE project. At this point, the larger flocks began to decrease significantly, dropping from >75% lay efficiency to near 55%. Both of the larger flocks decreased significantly though the 250 layer flock performed slightly better (2-3%).

The 100 layer flock did not struggle nearly as much as the other two flocks in the unusual summer heat. Their rate of lay gradually dropped throughout the summer, but this is normal for us as the birds begin to age. Throughout the summer the 100 layer flock averaged about 72% which is what we expect.

The most troubling part of the decrease in lay rate was that the larger flocks did not rebound from the midsummer heat until deep into fall. Overall, it was a difficult year for the layers but the SARE project enabled us to draw some knowledge from our struggles.

Something we noticed was that the chickens in the smaller flock were eating a greater amount of their ration (per hen) than those in the larger flocks. It is known that one way that heat affects animals is that they do not eat as much and if a layer is not eating enough, they will not ingest enough of their nutritional needs and their rate of lay will suffer because of it.

When we realized this, we bought additional feeders for the larger flocks. We theorized that the birds were all trying to eat in the cooler parts of the day, rather than through the whole day as they do in more mild temperatures. If this was the case, the feeders would be a bottle neck for them during these cooler times of the day to ingest enough feed to meet their laying needs.

An additional possibility for the rate of lay difference is that the larger flocks produced more heat as a whole in the night so that each individual bird did not cool down as much as the birds in the smaller flocks.

We almost never had issues with land predators because of the electrified poultry netting, however we always have issues with eagles and owls. We observed that the smaller flock lost a significantly higher number of chickens to eagles than the bigger flocks. We do not understand why this would be but we will continue to monitor this and see if it is a trend that continues in 2017. Potentially the landscape of the pasture made it easier for the eagles, as it is slightly hillier. Or maybe the eagles simply had success early with the smaller flock and pestered them more often.

At our presentation in January, an attendee said that in their experience the Red Sex Links are more prone to aerial predation. We have raised a variety of layers in the past but we settled on the Red Sex Links because they performed well on pasture and we like their disposition. However, we intend to experiment with a few different breeds this year to test if the red sex links are more prone to predation.

Work Plan for 2017

We intend to construct two additional small mobile pens for 100-125 hens. We want to fence these together so that the flock will include 200-250 hens but each mobile roost will hold fewer birds. We will track production and compare this with the other two flocks.

Our goal is to make the new mobile houses lighter. The mobile roost that we constructed last year was not very easy to move because it was quite heavy. We are working on a design so that it is lighter and easier.

Also we are adjusting the roosts on the inside to make a ‘V’, rather than the standard ‘A’ frame. Our thinking with this is that the ‘V’ frame may allow more airflow at night and help with heat dispersement in the heart of summer.

We will continue to track the efficiency of the different size flocks and compare the results against 2016.

We will also continue to work on a manual for a 100 layer flock and try to find venues to present our findings.

Outreach

In late summer of 2016 we held a field day on the farm. The sole focus was on raising layers on pasture. It was publicized in conjunction with Crosshatch, a non-profit organization that focuses on ecology and farming. It was part of a twilight-farm tour series.

The tour lasted about 2 hours and was attended by about 65 people.

In January 2017, Aaron presented at the Northern Michigan Small Farm conference. It annually has about 1000 attendees. Aaron’s session was entitled “The 100-Layer Flock on Pasture”. There were approximately 100-125 people in his session.