Abstract:

In order to investigate the interaction effects of transport and rest on the stress responses and meat quality of
broilers in summer, 189 white-feather broilers were randomly assigned to 9 treatments. The study design included three
transport time points (0.5, 3 h and 5 h, respectively), and three rest time points (0, 1 h and 2 h, respectively), and analyses of
adreno-cortico-tropic-hormone (ACTH), corticosterone (CORT), creatine kinase (CK), L*, pH, drip loss, cooking loss, lactic
acid, and glycogen were performed after broilers were slaughtered on commercial line. The results showed that ACTH,
CORT, CK, and pH values increased with prolonged transport time (P ＜ 0.05). However, L* value, drip loss, cooking
loss, muscle lactic acid and glycogen showed the opposite trend with increasing transport time (P ＜ 0.05). Meanwhile,
ACTH, CORT, and CK decreased with prolonged rest time (P ＜ 0.05), which had an insignificant influence on the rest
indicators (P ＞ 0.05). Factorial analysis results showed that transport time had a highly significant effect on all indicators
(P ＜ 0.01). Rest time had an insignificant effective on all other indicators (P > 0.05), exceptACTH and CORT. Interactions
between transport time and rest time significantly affected CORT, 1 h L*, drip loss, and cooking loss (P ＜ 0.05), however,
the impacts on other indexes were not significant (P ＞ 0.05). In conclusion, the transport in summer would result in stress
responses in broilers, which is adverse to meat quality. Reasonable transport time with proper rest time would relieve the
stress in broilers and improve their meat quality.

Key words: words: broilers, transport time, rest time, stress, meat quality