In Category #2 there are three basic areas that need to be addressed:

1. MOVEMENT RESTRICTIONS : Several research studies have shown that animals have a definite motivation for freedom of movement, but the consensus of new research studies is showing that a lack of roughage feeds which enable the animals to perform more natural feeding patterns causes greater discomfort to the animals. This is especially a problem in chicken broiler breeders and sows which have to be kept on a calorie restricted diet to prevent them from getting too fat to breed.

2. LACK OF ROUGHAGE FEEDS : Research has indicated that a lack of roughage feed and a lack of foraging activities involving the mouth may be a greater cause of abnormal behaviour than movement restriction.

3. GENETIC INFLUENCES : There are strong genetic influences. Calm, placid strains of animals are less likely to develop abnormal behaviours in a barren environment. Over selection for rapid gain has contributed to behaviour problems.
   Feather pecking problems in chickens may be reduced by genetic selection. It is possible to eliminate the need to beak trim chickens by selecting for strains that have less of an urge to peck.
   Research has shown that beak trimming
   may cause prolonged pain.

4. Sows and chickens which have been bred for tremendous appetite, drive, and rapid growth may still feel hungry even when they are fed a high roughage diet. Genetic selection for huge appetites may compromise the way of breeding animals that are kept on a restrictive calorie diet even when roughages are fed. To improve the way of breeding animals that have been over selected with high appetite drive and rapid growth would require a change in their genetics.

Category #2 also covers:

Objective, carefully conducted research will enable people to make decisions on behavioural needs. The strength of behavioural needs is influenced by genetics. Animals can be selected to reduce the motivation for a behavioural need.

Ian Duncan (at the University of Guelph, Onterio, Canada) has done some excellent research on the behavioural needs of chickens.

He has measured motivation by measuring the amount of weight a chicken will push to get to a dust bath or an enclosed nest box. He found that a chicken will lift very heavy weights to reach a secluded place to lay her eggs.
Some of the behavioural needs of chickens should be accommodated.

Nest building in the sow is another example of a highly motivated behaviour which may have to be accommodated.