Early T-maze behavior, puberty and egg production in Japanese quail selected for contrasting adrenocortical responsiveness.

MARIN R.H.; SATTERLEE D. G.; CADD, G. G.; JONES, R. B.

Indianapolis, Estados Unidos.

Congreso; International Animal Agriculture and Food Science (Poultry Science Association).; 2001

Poultry Science Association

Broiler chicks that traversed a T-maze quickly to reinstate contact with their companions (HP, high performance) then grew faster, showed greater sociality and lower plasma corticosterone (C) responses to an acute stressor than did slower (LP, low performance) chicks. Genetic lines differing in adrenocortical responsiveness are powerful tools for studying the relationships between behavior, stress and performance. Herein we asked if early T-maze behavior is related to the attainment of puberty and to egg production in Japanese quail selected for low (LS) or high (HS) plasma C response to restraint. At 3 d of age, 196 HS and 189 LS quails were tested in a T-maze and categorized as HP or LP if running times were < 25 s or >100 s, respectively. They were housed in mixed-category, mixed-line groups in brooder batteries until 4 weeks when they were caged in same-line, same-category pairs of 1 male and 1 female until 14 weeks. Thus, there were 4 treatment combinations, i.e., 19 HP-LS, 21 HP-HS, 23 LP-LS and 24 LP-HS pairs. Egg records were kept from the first oviposition for the next 8 weeks. HP birds reached puberty sooner than LP ones as shown by reductions in age at first egg and at 25% egg production (ANOVA, P<0.02). Post-hoc tests showed that age at first egg and at 25% egg production were lower (P<0.05) in HP-LS than LP-HS pairs. Overall hen-day egg production (HDEP) was greater (repeated measures ANOVA, P<0.04) in HP than LP quail. A numerical trend towards greater overall HDEP (+5%) in LS than HS quail failed to reach significance (P<0.34). Our results suggest that rapid negotiation of the T-maze was associated with accelerated puberty and an associated increase in HDEP in quail of two genetically diverse lines. These findings strengthen our proposal that this simple, non-invasive test could be a useful selection criterion for breeding programs to improve productivity. Keywords: Japanese quail; T-maze behavior; puberty.