Criteria for Welfare Assessment

Welfare of animals involves their subjective feelings. Hence it cannot be directly assessed. It is generally accepted that welfare comprise the morphological, physiological, behavioural and mental status of the animals, and most indicators are related to these scientific disciplines. Welfare is defined as “normal” morphological development and undisturbed physiological, behavioural and mental status of the animals. It is expected that this status allows the animals to successfully cope with the prevalent environmental conditions. The definition of “normal” or “abnormal” status of domestic animals is a crucial problem in assessing welfare. Genetic selection for morphological, behavioural and production traits has changed the phenotypical appearance and the physiological background of the domestic fowl. At the same time the environmental conditions have been changed dramatically. Attempts to use the Bankiva fowl under natural conditions as a base line for normality have failed so far, and welfare indicators for the domestic fowl are focussed on mechanisms which allow the specific breeds to cope with their environment. Morphological changes in body shape (crests, dwarfism), feathering (curled, silky, naked neck and scalelessness) have been suspected to impair the welfare of the birds. It is argued that these breeds may not be fit to survive under natural or quasi natural conditions. Morphological changes per se cannot be taken as indicators unless it is established that these characteristics lead to suffering as stated by physiological or behavioural indicators. Selection for high egg production has been related to potential risks of osteoporosis and high growth rate resulted obviously in reduced locomotor ability, leg disorders, ascites and sudden death syndrome. The interrelationships between production traits and welfare are complex and the discussion on this topic is controversial. Stress, diseases and metabolic disorders in general impair growth and egg production. Therefore normal production rates are considered as indicators for welfare by poultry keepers. In some cases, however, there are welfare problems despite high productivity, and low productivity may not have negative effects on welfare. It is important to collect information from various scientific disciplines. This information may not be consistent, and indicators of good and poor welfare arise within the same bird. The assessment of welfare in this case requires balancing of positive and negative aspects. There is no generally accepted solution for this problem so far. __________________________________________________________________________________