Separating the effects of group size, density, and enclosure size on movement and use of space in domestic fowl (Gallus gallus domesticus)

摘要: Title of Document: SEPARATING THE EFFECTS OF GROUP SIZE, DENSITY, AND ENCLOSURE SIZE ON MOVEMENT USE SPACE IN DOMESTIC FOWL (Gallus gallus domesticus) Erin Hoerl Leone, Ph.D., 2008 Directed By: Professor Inmaculada Estevez, Department Animal and Avian Science This project was designed to separate the confounded effects group size, density, enclosure examine role design its related parameters in shaping movement patterns use space domestic fowl. While previous research has suggested that size are highly relevant broiler (meat-type chicken) welfare, confounding between variables makes their individual contribution difficult distinguish. My novel treatment structure with 10, 20, 30 birds small (1.5 m 2 ), medium (3.0 large (4.5 ) enclosures enabled me determine impact while systematically controlling for density. Three designs: rectangular, square, square partitions maintain a constant perimeter area ratio, were employed order such as length width ratio. Enclosure most factors use, which immune influence Birds consistently had larger home ranges enclosures. The strong effect movement, altering response combinations. Movement appeared be greatest rectangular enclosures, where largest straight-line distance is available ratio declines at relatively slow rate increasing size. played significant determining nearest neighbor distances net displacement, these limited by presence increase interior reduce inactivity. did not appear restricted social interactions any Rather, physical mates even low density 6.7 birds/ act barrier dispersal movement. Group little on young Overall, this shown fowl overall amount design.