The Cobb 500 is a fast-growing
broiler chicken
Breed broiler is any chicken (''Gallus gallus domesticus'') that is bred and raised specifically for meat production. Most commercial broilers reach slaughter weight between four and six weeks of age, although slower growing breeds reach slau ...
breed. They can reach a 2 kg slaughter weight at 33 days old. They make up around half of all globally farmed chickens as of 2016.
The Cobb 500 is controversial due to their health problems.
Animal rights
Animal rights is the philosophy according to which many or all Animal consciousness, sentient animals have Moral patienthood, moral worth independent of their Utilitarianism, utility to humans, and that their most basic interests—such as ...
and
animal welfare
Animal welfare is the quality of life and overall well-being of animals. Formal standards of animal welfare vary between contexts, but are debated mostly by animal welfare groups, legislators, and academics. Animal welfare science uses measures ...
groups such as Open Cages have called for the industry to stop their use.
History
The Cobb linage descends from the Vantress chicken, which was bred for the USDA's
Chicken of Tomorrow contest
The Chicken of Tomorrow Contest was an animal husbandry contest held between 1946 and 1948 and sponsored by the American grocery store chain A&P, in partnership with the US Department of Agriculture (USDA), to encourage the development of broiler ...
in the 1940s. The Cobb line itself saw its initial development in the 1970s in
England
England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It ...
by Cobb-Vantress. The Cobb 500 in particular was introduced into the United States in 1985. In response, the US producer
Tyson Foods
Tyson Foods, Inc. is an American multinational corporation based in Springdale, Arkansas that operates in the food industry. The company is the world's second-largest processor and marketer of broiler industry, chicken, beef, and pork after JBS ...
acquired a 50% stake in Cobb-Vantress in 1986. In 1994, Tyson acquired full control of the company. The Cobb 500's share of all chickens has increased in the decades since.
In 2008, all Cobb line birds made up around 30-40% of global broilers. In 2016, the Cobb 500 alone was nearly 50%.
More broadly, fast-growing chickens now make up the vast majority of the global chicken supply. As of 2021, 90% of the global broiler population is part of either the Cobb or Ross lines, which are both fast-growing.
Health issues
The fast growth of the Cobb 500 is associated with an increased rate of various health problems. Compared to slower-growing chickens, they have a higher rate of
sudden death syndrome
Sudden death syndrome (SDS), a disease in soybean plants, quickly spread across the southern United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North Ameri ...
,
hock burns
Hock burns are lesions found on the hock joints of chickens and other birds raised on broiler farms. They are considered a form of contact dermatitis. These marks occur when the ammonia from the waste of other birds burns through the skin of the ...
,
Tibial dyschondroplasia
Tibial dyschondroplasia (TD) is a metabolic disease of young poultry that affects the growth of bone and cartilage.
Often occurs in broilers (chickens raised for meat) and other poultry which have been bred for fast growth rates. The tibial carti ...
, weaker disease resistance and
antibody
An antibody (Ab) or immunoglobulin (Ig) is a large, Y-shaped protein belonging to the immunoglobulin superfamily which is used by the immune system to identify and neutralize antigens such as pathogenic bacteria, bacteria and viruses, includin ...
response, bone deformations, and problems with walking.
References
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Chicken breeds
Ethically disputed business practices towards animals