Effects of temperature manipulation during late embryogenesis on broiler performance

الملخص EN

This study aimed to elucidate the effects of thermal manipulation (TM) for different periods during different ages of embryogenesis on the post hatch performance of broiler.

Eggs from Ross breeders were subjected to heat treatment of 38.4°C at day 19 for 6h per day (T1) and in T2 eggs were subjected at 19 and 20 days old for 3h per day.

Control eggs were incubated at 37.4°C.

Eggs were submitted to the same humidity range (80-85%).

A total of 270 one-day chicks obtained from the treated eggs in the hatchery, were distributed randomly on the treatments with three replicates per treatment (30 chicks per replicate).

Chicks reared on the floor, and Aviagin rearing guides of Ross strain was applied for environmental control.

A pelleted feed and water were offered adlibitum.

Results showed significant (p<0.05) differences in body weight (BW), body weight gain (BWG) and feed intake (FI) during the grower phase, while values of feed conversion ratio (FCR) differed insignificantly among treatments.

In overall, higher BW and BWG were found in T1, while lowest value of FI was recorded in T2, both treated groups showed improvement in FCR compared to the control.

Male broilers obtained higher BW with embryos exposure to higher temperature for 3h in days 19 and 20, while female broilers obtained higher BW with both treatments compared to the control.

The production index improved in both treated groups compared to control and lower mortality was recorded in T1, while highest value recorded in T2.

In conclusion results indicated that TM of broiler embryo during late embryogenesis period improved post hatch performance of broiler chickens