Date of Graduation

12-2024

Document Type

Thesis

Degree Name

Master of Science in Poultry Science (MS)

Degree Level

Graduate

Department

Poultry Science

Advisor/Mentor

Weimer, Shawna

Committee Member

Orlowski, Sara K.

Second Committee Member

Williams, Zac T.

Keywords

Athens Canadian Random Bred; Judgment Bias Test; Red Junglefowl; Thermal Images; Tonic Immobility

Abstract

Our understanding of how poultry perceive and interpret their environment is essential to enhancing their welfare; over the years, animal welfare science has relied on measures of the behavioral and physiological components of affective states (positive and negative) as welfare indicators. There is an increasing interest in the study of chicken’s affective states using the Judgment bias test (JBT) as a tool for assessing welfare through their responses to ambiguous cues. This study investigates the cognitive performance of two chicken breeds with different evolutionary histories: Red Junglefowl (RJF), the primary ancestor of modern chickens, and Athens Canadian Random Bred (ACRB), a rustic domesticated broiler breed from the 1950s, by examining their responses to ambiguous stimuli in the JBT and comparing the fear and stress responses of the chickens that were and were not subjected to the JBT at two ages. Latency to approach cues varied significantly, with chickens consistently showing shorter latencies to approach positive (POS) cues than neutral (NEU) and RJF chickens exhibiting faster responses than ACRB at the older age, indicating better memory. Longer latencies in the tonic immobility test revealed higher fearfulness in RJF than in ACRB. Additionally, tested chickens, particularly males, displayed longer durations of tonic immobility than untested chickens. Thermal image analysis of eye and beak temperatures revealed that chickens subjected to the JBT had lower eye and beak temperatures, indicating higher stress levels. These findings highlight the influence of domestication on cognitive and emotional responses in chickens and underline the importance of considering stress during cognitive tests.

Download

Included in

Agriculture Commons

Share

COinS