抄録
This study was carried out to investigate the behavior and physiological conditions of hens housed in cages with or without perches. The physiological parameters investigated were heart rate (HR), body temperature (BT) and locomotor activity (LA) using a radiotelemetry system. Six White Leghorn hens (90-weeks-old) were used after transmitters implantation. Following the preconditioning period for at least 10 days, the behavioral and physiological data were recorded for 2 consecutive days, which were the data in the control cages without perches (C). After that, the same hens were exposed to the following types of cages : conventional cages with perches available all day (P24), followed by conventional cages with perches from 19.00 to 08.00 hours (P13), and finally housed in conventional cages with perches from 19.00 to 04.00 hours (P9). The interval between each trial was a 10 days to habituate the hens with their new environment. Immediately following this, the behavioral and physiological data were recorded for 2 consecutive days for each trial. The only significant behavioral difference was found in the time consumed in resting, which increased significantly in P24 cages than in C and P9 cages (P<0.05). Our physiological data during the light period indicate that the hens in P24, P13 and P9 cages had a significantly higher heart rate than in C cages (P<0.01). On the other hand, hens in P24 cages had a significantly lower BT than in C, P13, and P9 cages (P<0.01), however, hens in P24 cages had a significantly higher LA than in C, P13 and P9 cages (P<0.01). Moreover, during the dark period, hens in P24 cages had a significantly lower HR, BT and LA than all the other treatment (P<0.01). These results suggest that the use of cages with perches might be important for the hens’ welfare than those without perches.
