A project of the Atlantic Headquarters of the University of Costa Rica (UCR), in conjunction with the School of Zootechnics, proposes the grazing system as a key tool to produce eggs without affecting the health of the hens. By means of this method, the animals have enough space to move around and feed themselves throughout the day, improving their quality of life and their coexistence in a group, details an article of the UCR.
What is grazing?
In simple words, it is a system in which the animals go out to a green area, with a forage bed of at least 10 centimeters to feed. In agriculture, grazing is one of the methods used to convert grass and other forages into meat, milk and other products (such as eggs). In this case, the protagonist is the chicken, who chops the grass to eat it.
The researcher and coordinator of the Dairy Module of the Atlantic Headquarters and professor of the School of Zootechnics, Rodolfo Wing Ching, has joined forces with Ana Cruz Bermúdez and Sianny Chavarría Zamora, 2 graduated students of Agronomic Engineering who have investigated the main advantages of this method.
Wing Ching assures that in order to maintain good levels of grazing, the continuous revision of the land is imperative. “In the grazing system it is necessary to maintain the forage consumed by the hens, since sometimes the land is so eaten that there is not enough grass to consume”, said the academic.
Do they eat all the foliage?
They do not. It happens that although they have a large lot to move, the hens prefer to concentrate in a small space of the land to graze, usually for fear of exploring or because they prefer the shade. The drawback here is that by always eating from the same place, they do not allow time for the foliage to grow back properly. That is why continuous maintenance is necessary.
According to the UCR, researchers have studied the behavior of almost 300 chickens in 2 lots located in the Dairy Module of the Atlantic Headquarters in Turrialba.
Diet: grains, grass, and insects
To ensure an adequate balance of nutrients, the grazing hens should be fed grain and balanced feed based on cereals, which constitute about 95% of their daily ration. The grass (plus the insects that are in it) can constitute the remaining 5% of the ration.
According to Wing Ching, this small percentage is very significant, since it can supply the caloric requirement and the natural vitamins, minerals and amino acids that these birds need to feed themselves properly.
“With the diagnosis we made for the study, we realized that there is misinformation about the management of grazing systems. There are producers who take 10% or 20% of the feed off the chickens to eat grass, but the problem is that this rather generates malnutrition. They have a table of food consumption and must be respected”, said the researcher.
Every 14 days the investigators inspect the lands where the chickens graze. A person is responsible for maintaining the 2 lots constantly.
A whole process of socialization
Although this method helps chickens roam more freely, it also improves their collective coexistence. How? The study indicates that these birds live in a sort of hierarchy, divided between the leading and subordinate hens. When they live in overcrowding, those in charge peck at the rest to break through in order to eat and hatch. Occasionally, this generates serious injuries in a large number of the group.
In contrast, in the grazing system, when the “forts” go out to graze, the “weak” are left with a lot of space to drink water, eat food and even have time to lay an egg. This improves the health of the whole flock and benefits the production, since it lowers the levels of stress in the hens; a factor that is decisive for them when hatching.
One drawback of this practice is that coliforms (small contaminants) may be present in the eggs, since there is more room for the chickens to move, and there is a greater possibility that they will soil their legs and eggs at the same time hatch them. Those in charge of the project declare that they try to keep this controlled with iodine baths and weekly controls to lower the bacterial load.
Green and sustainable trade
Integrating grazing eggs into their offer allows companies to capture a portion of the growing market for green and sustainable products. In addition to this, it motivates consumers to appeal to consume foods of animal origin produced with high standards of care and maintenance in the period of preparation. But, do these standards exist?
The thesis of Sianny Chavarria determined that as the hen’s age advances the egg weight, the weight of the shell and its thickness increases.
According to the researchers, there is no specific list of actions to exercise a good grazing system in the country. What does exist are investigations (such as Ana and Sianny) that can function as an input to create these norms, and thus propose them as policies that are later established by the public institutions in charge.
For Ana Cruz it is crucial “to inform the current conditions of alternative poultry systems in Costa Rica, and the need to establish critical points in them to ensure welfare to the birds and quality product to the consumer”.
In his thesis, Cruz set out to generate a productive model for laying hens with access to grazing. This was achieved thanks to the obtaining of productive parameters and the characterization of facilities and grazing areas in 5 egg marketing systems with access to grazing in the Greater Metropolitan Area (GAM).
For its part, Sianny Chavarría’s thesis compared 3 different production systems (including grazing) and yielded beneficial results for the pasture method. She made a sensory panel of taste to 108 habitual egg consumers, to evaluate which egg these people preferred, 38.9% said they preferred to graze.
Also, Chavarria identified that “the respondents buy the egg without noticing where it comes from since what matters most to them when buying is the price. However, they proved to have a notion about the different production systems and said they felt willing to pay more for the egg if within the productions the hens were guaranteed animal welfare, good nutrition, and hygiene”.
