Written by: Dr. Jacquie Jacob, University of Kentucky
The domesticated chicken is a descendant of the jungle fowl of Southeast Asia, whose natural habitat is forested areas. Today's chickens have not lost the urge to roost, especially at night. Consequently, you may wish to include perches in your poultry housing. Laying hens make full use of perches. Meat-type chickens (broilers), due to their extra weight, typically do not use perches. Most waterfowl do not use perches; however, Muscovy ducks, like chickens, do prefer to roost.
Although it is not mandatory in the United States to include perches in poultry housing, research has shown that chickens prefer having them. Recent animal welfare legislation in the United Kingdom requires poultry growers to provide birds with perches, with a minimum of 15 centimeters per hen (about 6 inches per hen) of perch space under regular standards and 18 centimeters per hen (about 7 inches per hen) under organic standards. Moreover, there must be a minimum of 30 centimeters (about 12 inches) of horizontal space between perches and 20 centimeters (about 8 inches) between a perch and the wall. Also, the perches cannot have sharp edges.
Providing laying hens with perches is a way to relieve their stress and to reduce certain injuries and cannibalism. During the day, hens that are lower in the pecking order use the perches to escape pecking from more dominant hens. This ability to escape reduces the incidences of injury to the head and neck caused by aggressive pecking and cannibalism caused by severe feather pecking. At night, when all the hens perch, the more dominant hens take the higher perches.
Perches can play a role in manure management as well. Perches allow birds to stay off the floor, particularly during the night. Consequently, manure tends to accumulate under the roost area, and the rest of the bedding material in the house stays cleaner.
The use of perches also can affect egg laying. A higher level of floor eggs has been reported for flocks without access to perches.
Domesticated chickens are considerably heavier than the mature jungle fowl, and the modern chicken has a relatively smaller wing surface area. These traits make the modern chicken an awkward flier. As a result, often an increase in keel injuries exists in chickens with access to perches, due to misjudged landings.
Research from 2010 and 2011 showed that the use of perches is associated with a higher incidence of skeletal damage (such as bone fractures and keel deformations) and fat pad lesions. Additional research is under way to determine the best materials and design of perches to reduce the incidences of these issues.
If you plan to include perches in your poultry housing, you should introduce the perches to the flock when the birds are still young. Rearing chickens without early access to perches has been shown to impair their ability to use the perches as adults.
Location and placement of perches are important. Locate perches in an area of the house where they will not interfere with the daily care of the birds, including feeding, watering, and egg gathering. Also, the roosts should be removable to allow you to clean out the manure that accumulates under them. Place the lowest perch about 3 feet off the floor to minimize the opportunity for other chickens to feather peck a chicken using this roost. Consider the vertical distance between perches too. If the vertical distance between perches is too large, it is more likely that the chickens will misjudge their landings and collide with perches, thereby injuring their keels. Also, chickens find it difficult to land safely on perches when jumping down, so ensure that there is sufficient floor space to allow the chickens to land safely when leaving the higher perches.
Perch shapes and the materials used to make perches vary. Europeans typically use round iron tubes for perches to minimize infestations of red mites (Dermanyssus gallinae), which don't like such perches. However, these perches are associated with a higher risk of keel deformations. Some flock owners have used plastic perches with mushroom shapes, but red mites hide during the day in the areas where these perches are connected to each other. Wooden perches also are very sensitive to red mites. In Europe, the presence of red mites is a more significant problem for poultry producers than keel deformations, so European producers prefer the iron tube perches. If red mites are not a concern, wooden perches are the best option because more layers use perches if the perches are square rather than round.