The ontogeny of thermal nociception in domestic fowl: Thermal stimulus intensity and isolation effects

✍ Scribed by Richard A. Hughes; Kenneth J. Sufka

• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 764 KB
• Volume: 23
• Category: Article
• ISSN: 0012-1630
• DOI: 10.1002/dev.420230204

✦ Synopsis

Socially housed leghorn cockerels were confined to a heated grid (55,57, or 5YC, Experiment 1; 59, 61, or 63"C, Experiment 2) and tested at posthatch ages of 14 days (Experiment 1) and 1, 3, 7, or 14 days (Experiment 2). In Experiment 1, chicks performed a discrete jump response only at 59°C. In Experiment 2, jump latency was inversely related to temperature at each age but significantly so only at 7 and 14 days posthatch. At the highest temperature, jump latency did not differ significantly across ages. At medium and low temperatues, latency increased from 1 and 3 to 7 days posthatch (antinociceptive effect) and decreased thereafter. Chicks raised in isolation from hatch to 7 days posthatch (Experiment 3) did nut display the increased jump latency (antinociceptive effect) displayed by socially raised chicks. Developmental increases in jump latency may reflect stress-induced antinociceptive concomitants of neophobia that emerge with age in this precocial species and social experience may be required for the normal development of this stress-induced antinociception.

Several procedures have been described for the evaluation of nociception in domestic fowl (Bardo