References
- Bareham , J. R. 1972 . Effects of cages and semi‐intensive deep litter pens on the behaviour, adrenal response and production in two strains of laying hen . Br. vet. J. , 128 : 153 – 162 .
- Black , A. J. and Hughes , B. O. 1974 . Patterns of comfort behaviour and activity in domestic fowls: A comparison between cages and pens . Br. vet. J. , 130 : 23 – 33 .
- Goussopoulos , J. , Carles , Y. , Prud'hon , M. and Bacou , F. 1973 . Enregistrement graphique de l'activité et du comportement alimentaire du poulet . Annls Zootech. , 22 : 133 – 145 .
- Hughes , B. O. and Duncan , I. J. H. 1972 . The influence of strain and environmental factors upon feather pecking and cannibalism in fowls . Br. Poult. Sci. , 13 : 525 – 547 .
- Levy , D. M. 1944 . On the problem of movement restraint . Am. J. Orthopsychiat. , 14 : 644 – 671 .