Broiler breeding flocks: management and animal welfare

This chapter discusses the management of broiler breeders, that is, the parent stock of broiler chickens, and welfare issues related to the different life stages of broiler breeders. Where commercial broilers are the product of a cross of four lines, broiler parent stock (broiler breeders) are the product of a cross of two lines; both the male and female broiler breeder is the product of a cross of a specific paternal line and a specific maternal line (Hiemstra and Ten Napel, 2013). The actual figures on the number of broiler breeders worldwide are lacking; as an indication, in Europe the number of broiler breeders is estimated to be 44 million (Horne and Bondt, 2014). Management and housing of grandparents and great grandparents (but not pedigree stock) is to a large extent similar to that of broiler breeders (EFSA, 2010; Hiemstra and Ten Napel, 2013) and not described in this chapter. Nowadays, three companies dominate the world market for broiler breeding stock: Aviagen Broiler Breeders, Cobb-Vantress and Hubbard.The majority of the broiler breeders worldwide are the parent stock of the so-called standard or fast growing broilers, which reach a body weight of 2.5 kg in 42 days or ess (EFSA, 2010). Dwarf parental females are used to produce broilers of intermediate (2.2 kg in 56–63 days of age) or slow growth rate (2.2 kg in 70–80 days of age) (De Jong and Swalander, 2013). Although worldwide only a small percentage of parent stock for intermediate or slow growing broilers is housed, in some countries a larger proportion of the total number of broiler breeders produce intermediate or slower growing broiler strains. For example, in France, the majority of the parent stock –85% according to De Jong and Guemene (2011) – are parents of intermediate or slower growing broiler strains (EFSA, 2010). In Europe, about 8% of the broiler breeders are estimated to be parent stock of intermediate or slower growing broilers (Horne and Bondt, 2014).We provide a short, general description of housing and management of broiler breeders during both the rearing and the production period in the next paragraph. In addition, we focus on (major) welfare issues related to the management of broiler breeders and the current state-of-the-art research related to these welfare issues.