Table 1.

Additional information given in the survey on culling day old male layer chicks.

Content of information provided	When was information provided	Prior to which questions—paragraph content
The poultry industry is specialized. Chickens for meat and chickens for eggs. This survey is aimed to test your knowledge and opinion on eating cockerel meat	At the start of the questionnaire	1–8.Paragraph 1. Knowledge on the poultry industry
In the Netherlands, 90,000,000 chickens are kept yearly. 45,000,000 chickens for meat and 45,000,000 chickens for eggs. Because cockerels of layer chicken do not lay eggs they are culled at the hatchery. Once chicks hatch sex is determined manually by a specialist. Once the sex is determined to be male, male layer chicks are culled via CO2 asphyxiation. Yearly 45,000,000 male layer chicks are culled.The culled chicks are used for zoos, reptiles and birds of prey and other animals.	After first paragraph of questions regarding the numbers of chicken in the Netherlands, which day old male chicks are culled (broiler and layer or only layer), the sexing method, the method of culling and what happens with the culled male layer chicks.	9–12Paragraph 2. Acceptance of culling day old chicks
Culling day old chicks is causing a discussion on animal and ethics. Research is being conducted on alternatives for culling day old layer males. In this survey we look at three alternatives. We consider herein the perspective of keeping the animals under the highest welfare conditions.1. Keeping layer males for special cockerel meat products.2. Double purpose chickens for keeping the cockerels for meat and the hens for egg production.3. Sex determination of the embryo in the egg. With a needle fluid is being taken from the embryo which is used to determine the sex. Male embryos will be excluded from further development and used in animal feed.	After paragraph 2. Acceptance of culling day old chicks.	13Paragraph 3. Acceptance of alternatives to culling day old male layer chicks19Paragraph 4. Preference of alternatives to culling day old male layer chicks
Broiler chickens are slaughtered at 6 weeks of age. When cockerels of layer breeds will be kept for meat this takes ~15 weeks, because they take longer to grow. The feed and care costs are higher as compared to broiler chicken. This makes the meat of these layer cockerels more expensive than meat of broiler chicken. Meat from cockerel layers is less tender than meat from broiler chicken, and therefore the meat is processed into sausages or burgers.	After paragraph 2. Acceptance of culling day old chicks.	13–18Paragraph 3. Acceptance of alternatives to culling day old male layer chicks19Paragraph 4. Preference of alternatives to culling day old male layer chicks
A double purpose chicken is a chicken breed which can be used for meat and eggs. The meat of double purpose chicken is more expensive because they do not grow as fast at the broiler chicken. The feed and care costs for double purpose chicken are higher as compared to the broiler chicken.	After paragraph 2. Acceptance of culling day old chicks.	13–18Paragraph 3. Acceptance of alternatives to culling day old male layer chicks19Paragraph 4. Preference of alternatives to culling day old male layer chicks
Layer cockerel meat is mainly being used for sausages and burgers. This is currently the cockerel burger from layer cockerels available in one specific supermarket chain.	After question 31 in Paragraph 6. Willingness to pay for chicken products	32