hsus-a-comparison-of-the-welfare-of-hens-in-battery-cages-and-alternative-systems

Hsus-a-comparison-of - An HSUS Report A Comparison of the Welfare of Hens in Battery Cages and Alternative Systems Sara Shields Ph.D and Ian J.H

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
An HSUS Report: A Comparison of the Welfare of Hens in Battery Cages and Alternative Systems | Prepared by Drs. Shields and Duncan 1 An HSUS Report: A Comparison of the Welfare of Hens in Battery Cages and Alternative Systems Sara Shields, Ph.D., * and Ian J.H. Duncan, Ph.D. Abstract Housing systems for egg-laying hens range from small, pasture-based flocks to large, commercial-scale operations that intensively confine tens of thousands of hens indoors. The overwhelming majority of laying hens used for commercial egg production in the United States are confined in battery cages and provided 432.3 cm 2 (67 in 2 ) of space per bird. Cages prevent hens from performing the bulk of their natural behavior, including nesting, perching, dustbathing, scratching, foraging, exercising, running, jumping, flying, stretching, wing- flapping, and freely walking. Cages also lead to severe disuse osteoporosis due to lack of exercise. Alternative, cage-free systems allow hens to move freely through their environment and to engage in most of the behavior thwarted by battery-cage confinement. Given their complexity, cage-free systems can be more challenging to manage and may require superior husbandry skills and knowledge. Laying hens must be genetically suited to the alternative housing system to realize its full welfare advantages. Regardless of how a battery-cage confinement system is managed, all caged hens are permanently denied the opportunity to express most of their basic behavior within their natural repertoire. The science is clear that this deprivation represents a serious inherent welfare disadvantage compared to any cage-free production system. Cages and Alternative Systems Three basic housing systems are used in commercial egg production in the United States: battery cages, barns, and free-range. An estimated 95% 1 of the 280 million hens in the U.S. egg-laying flock 2 are confined in battery cages. 3 Egg industry guidelines recommend 432.3 cm 2 (67 in 2 ) of floor space per typical egg-laying hen, 4 and the most commonly used cages hold 5-10 birds per cage. 5 Cages are placed side by side, lined in rows, and stacked in tiers up to five levels high; tens of thousands of hens can be caged in a single building. Conventional battery cages provide a feed trough and water lines, but are otherwise barren environments. Scientists using preference testing techniques have demonstrated that hens generally prefer more space than is provided to them in a conventional battery cage. 6,7,8,9,10 Alternative laying hen housing systems, barns and free-range, vary widely both in design and management practices and requirements but, in contrast to battery cages, allow birds to move about freely. In barn systems, hens do not have outdoor access but are provided with nest boxes and often perches and loose substrate (litter or sand) for dustbathing, scratching, and foraging. Barns may be single- or multi-level structures. Single-level * Dr. Shields received her Ph.D. in Animal Behavior from the University of California at Davis and serves as a consulting
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 01/16/2012 for the course BI 200 taught by Professor Potter during the Fall '11 term at Montgomery College.

Page1 / 28

Hsus-a-comparison-of - An HSUS Report A Comparison of the Welfare of Hens in Battery Cages and Alternative Systems Sara Shields Ph.D and Ian J.H

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online