You may recall back in February we shared the exciting news that Seelye Brook Farms was selected for a Sustainable Agriculture Demonstration Research Grant by the Minnesota Department of Agriculture. We developed the idea to test how different pasture-based management methods for pastured poultry would affect farmer profitability, animal welfare, and nutrient composition of chicken meat for our consumers. Randy found out about research grants through the Sustainable Farming Association of Minnesota (SFA), of which Seelye Brooks Farms is a member.
We partnered with Minnesota farmer and SFA Livestock and Grazing specialist Kent Solberg to design an experiment. After applying for the grant to research our idea, we were selected and began the study in May 2018. If you visited us on our Open Farm Day, you saw the chickens in the brooder right before they were placed on pasture.
So what’s the big idea?
Many of our customers and others who are concerned about the current conventional food system in the USA are familiar with farmers like Joel Salatin from Polyface Farms. You might recognize him from one of the many documentaries he has appeared in including Food, Inc. Salatin is a pioneer in pastured poultry production and brought the idea of a bottomless, mobile poultry pen (aka a “chicken tractor”) into the mainstream. Hundreds if not thousands of farmers use this system shown below, including us here at Seelye Brook Farms.
The chicken tractor has multiple benefits for pastured poultry, humans, and farms. First, it moves birds around on pasture so they have access to fresh green grass, bugs, and sunshine. Salatin calls this “allowing chickens to express their ‘chicken-ness'”. This environment is what chickens experience when they aren’t being raised in large, conventional confinement poultry houses like nearly all of the chicken raised for meat in America. (Yes, even “free range” and organic chicken from large-scale producers typically rear birds in massive poultry buildings. These producers bend the intent of the USDA National Organic Board’s organic standards by providing limited outdoor access, instead of actually raising chickens outside on pasture.) The tractor provides predator protection as well, improving animal welfare for the chickens.
Second, moving chickens in tractors improves the soil of a farm by spreading out chicken manure as a fertilizer. Since the mobile pen is rotated around pastures, it mimics birds in nature who follow large herds of four-legged creatures feeding off the bugs that grow in the leftover manure. Avoiding stationary housing also has a positive environmental impact, by not creating a nitrogen overload in any one place like a conventional operation would do which requires remediation to fend off pollution.
Lastly, when chickens move around on pasture, they ingest fresh green grasses, weeds, seeds, ants, flies, moths, beetles, grasshoppers and just about anything else they can. The green grasses provide antioxidants like beta carotene and change the fatty acid profile of the chicken meat, skin, and fat (for the better!). The chickens become part of the ecosystem by eating from their surroundings, which reduces the feed required to bring them to finished weight, promoting a more sustainable agriculture.
Comparing how chickens are raised on pasture
In sustainable agriculture circles, the practice of “day ranging” has been around for 25+ years. When chickens are day ranged, they are kept in some sort of housing like a chicken tractor, but are allowed to (actually) free range on a section of pasture. This is different from just keeping the birds in a chicken tractor and moving it once or twice a day, which is the most common management practice and the one popularized by Salatin. Recently day ranging has become popular again on the basis that it may be better for animal welfare and easier for farmers. Day ranging still rotates the chickens around the pasture within a protective electric fence, but the chickens are given more simultaneous access to pasture to hunt insects and feed on grasses.
Herein lies our research study: to compare broiler chickens raised in a chicken tractor full time versus chickens that are allowed to day range. At Seelye Brook Farms, we are passionate about producing nutrient-dense food for our customers. Therefore, our production methods and livestock management practices are evaluated based on their ability to improve the land, enhance livestock welfare, and optimize the nutritional quality of our farm products. In this case, that means we are always looking for ways to raise our pastured poultry in the most humane ways that make sense for us (and fellow farmers), and which bring real value to our customers.
We set out to do side-by-side trials of pastured broilers in full-time mobile chicken tractors, and birds in the day range system. With the greater access to pasture at a time, it seems a reasonable assumption that flocks in a day-range system could provide two specific benefits:
- they may require less supplemental feed (and therefore cheaper for farmers to raise) by having access to un-soiled, non-trampled pasture, and
- the highly-nutritional forages and peak insect populations in the pasture may produce a chicken with a better nutritional profile for human consumption.
By doing side-by-side trials, we were able to measure the feed consumption, weight gain, required labor, and nutrient composition of the chickens raised in the two systems. Capturing data about these factors will allow Seelye Brook Farms to help other farmers determine if day ranging is viable for them, and will help us ensure that we are raising nutritious chicken for our customers in an efficient and humane way.
The results are in
If you want to dive into the full nitty-gritty details including all the data tables and analysis, you can access the full report here: Year 1 report. This is just the first year of a two-year the study. You can check back at the end of 2019 for the final results where we compare the results over multiple growing seasons and with a different meat bird breed.
Summary (for consumers)
For consumers, our study is mainly relevant for the nutritional testing of the chicken meat that was harvested from the birds that were raised for the study. We are pleased to report that the birds were in great health and grew within expectations for size for our climate. Our current customers also had great things to say about the quality and taste of the meat.
We compared our pasture-raised birds to the standard reference values given by the USDA National Nutrient Database (updated in 2018). Here’s is a summary of the nutritional content of the breast and thigh meat (with skin) that we had analyzed. Compared to the USDA standard values, our pastured-raised broilers on average had:
- 300% higher vitamin E content,
- a 68% decrease in total fat as well as a 63% decrease in saturated fat,
- a 64% decrease in omega-6 to omega-3 ratio (5.4 to 1, compared to 14.8 to 1 for the standard values),
- a slightly higher amount of cholesterol (about 3% increase).
The good news is that our study confirmed that pastured-raised chickens are superior to conventionally-raised chickens in terms of the nutrition they provide to you. This is the case regardless of whether the birds were in a chicken tractor full time, or day ranged.
While many consumers might not want to know “how the sausage is made”, some may be interested in more of the production factors that were studied in this project. If that is you, keep reading.
Summary (for farmers)
For farmers who are looking to start into pastured poultry production or are curious about trying other production methods, the following summary may be helpful in determining if day ranging will be viable for their context.
- Labor requirements: In general, the day range system required 20-39% extra labor depending on how quickly the additional infrastructure (poultry netting, electric fence energizer) can be set up by the farmer.
- Mortality: In a day-range system, the chickens are much more exposed to the possibility of predation from aerial predators, or predators that can compromise an electric fence more readily than a chicken tractor. However, our farm did not experience any predation in the Spring or Fall groups that were grown out. This is obviously very sensitive to each farm’s predator context.
- Growth and Feed Usage: Day-ranging increased the feed conversion ratio (FCR) in the early parts of the season by 3.8%, but became an advantage in the mid- to late-season (FCR decreased by 1.8%) presumably because temperatures were higher, forage was more plentiful, and insect populations were at or near peak levels.
- Nutrient Composition: There was not strong evidence that day ranging produced chickens with significantly different nutrient composition. Instead, the more favorable values of Vitamin A and fatty acid composition (including omega-6:omega-3 ratio) came when the broilers were on the best pasture (thriving grass and abundant insect populations).
- Profitability: Day ranging is not likely to result in lower production costs due to the increased labor component and additional infrastructure unless the farmer can garner a premium by marketing based on the “free-er range” nature of the day range system with their customers.
This work was funded by an Agricultural Growth, Research, and Innovation (AGRI) Program Sustainable Agriculture Demonstration Grant from the Minnesota Department of Agriculture.
The AGRI Sustainable Agriculture Demonstration Grant supports innovative on-farm research and demonstrations. Projects must explore sustainable agricultural practices and systems, and findings are published in the Minnesota Department of Agriculture’s annual Greenbook publication.
To learn more about the AGRI Sustainable Agriculture Demonstration Grant, visit https://mda.state.mn.us/grants/agri.aspx.