Animals and Society Institute

Good early life conditions are increasingly recognized as essential for animal welfare later in life. The use of light during incubation might improve coping capacities and welfare in later life in poultry, by more closely approximating chicken natural environments, compared to the current conventional incubation in darkness. Due to the position of the embryo in the egg just before hatching, the two brain hemispheres receive different amounts of light stimulation via the eyes. This unequal stimulation results in increased lateralization of the brain, which is the specialization of brain hemispheres on certain functions. In current commercial practice, chickens are incubated in complete darkness. Previous studies showed promising results of light during incubation on broiler welfare: more lateralized chicks, a more pronounced daily behavior rhythm, earlier onset of melatonin rhythms, and lower stress reactions to various stressors after hatching. However, information about the effects of light during incubation on laying hens is scarce. Research is necessary on both white and brown egg layers, as stronger effects are expected in hybrids coming from white eggs than brown eggs. In addition, white hybrids are known to be flightier and more sensitive than brown hybrids. Light during incubation could have different effects on both types of hybrids. For this thesis, Dekalb White (DW) and ISA Brown (ISA) eggs were incubated in complete darkness (dark) or in a light-dark cycle of 12h of green light and 12h of dark throughout incubation (light), resulting in four treatment groups of 100 chickens each: DW-dark, DW-light, ISA-dark, and ISA-light. Light transmission was higher through white eggshells than through brown eggshells. Light during incubation had no effects on hatching characteristics or brain measurements, and only few effects on fear of humans and cognition tests. There were hybrid effects on some hatching characteristics, most tests about fear of humans, one brain measurement, and some cognition tests. Despite the difference of light transmission through eggshell between hybrids, there was no interaction between incubation treatment and hybrid on hatching characteristics, on fear of humans or on brain measurements, and the effects on cognition were inconsistent. Green light during incubation did not negatively affect hatching characteristics in either DW nor ISA laying hen hybrids, and did not decrease fear of humans as much as expected. In addition, light during incubation affected the brains and cognition of laying hens at different life stages post-hatching, but the effects were not consistent across tests or hybrids. As such, the light regime used in this study does not seem as promising as expected to improve laying hen welfare. In parallel, the brown hybrid was usually less fearful than the white hybrid, although there were some exceptions depending on the stressor. Future research should focus on the effects of a longer exposure to green light during incubation on laying hen welfare. In parallel, research set-ups and husbandry guidelines for commercial settings should be adapted to the specific hybrids used.

As announced in two recent issues, on the occasion of the 30th anniversary of the publication of Society & Animals, in partnership with Brill Publications we are making ten previously published articles available for a limited time in Open Access. Articles are selected that: (1) demonstrate the expansion of the field to an increasing number of interfacing disciplines, (2) suggest changes in policy and practice involving human-animal relationships, and/or (3) make important conceptual advances in the field. Here is the third and final batch of articles the full texts of which are available for three months from the publication of this issue:

Abstract This is the third in a series of reports on the state of the field of Human-Animal Studies. In the introductory section, major terms in the prevailing definition of the field—Human-Animal Studies is the interdisciplinary study of human-animal relationships—are unpacked and critically analyzed. Subsequent sections deal with the field’s past, present, and possible futures. A schematic history of the field considers both scholarly contributions and programmatic inroads in the academy. The current state of the field section describes its breadth in terms of publication venues, disciplines that interface with it, and the variety of methods employed. It also offers a description of several common strategies that critique the received view of the categorical divide between human and other animal beings. The final section highlights both the potential of and anticipated roadblocks to each of several future trajectories.

Abstract Reframing atheism as a set of positive beliefs, I describe a way of living in the world in which atheism requires faith, defined as a commitment to beliefs that are both logically and empirically not subject to proof. Faithful atheists have faith in and take spiritual nourishment from being in the presence of a world which is awesome and wonderful both in that it is immediately available and that it is and will always remain at least partly opaque to understanding. They do so without positing a God or inflating the reach of reason. Their way of living is characterized by “sensational presence” (full attention to and staying with a present moment) and the courage to accept that their access and understanding whether in relation to other people, other animals, and nature more generally, is always limited. This inherent residual opacity grounds their respect and sense of mystery in each of these realms.

Kommentar til “The Co-occurrence of Human Violence andAnimal Abuse: Policy Implications and Interventions” af LisaLunghofer og Kenneth Shapiro, Animals and Society Institute.