Journal Article

Effects of thermal manipulations during embryogenesis of broiler chickens on developmental stability, hatchability and chick quality

Erdoğan, S., Narinç, D., Aksoy, T., Tahtabiçen, E.

2016

Overview

Stress based on high temperature and humidity reduces the production performance of fast-growing broilers and causes high mortality. Temperatures higher than optimum have been applied to broilers in the embryonic period in order to overcome thermal stress. This study was conducted to investigate the effects of exposure to two long-term high-thermal environments on the developmental stability of embryonic growth, hatchability and chick quality. For this purpose, 600 broiler eggs were incubated. Treatments consisted of eggs incubated at 37.8°C at 55% relative humidity throughout (control), heated to 39.6°C at 60% relative humidity for 6 h daily from 0 to 8th day, and heated to 39.6°C at 60% relative humidity for 6 h daily from the 10 to 18th day. Embryo weights and lengths of face, wing, femur, tibia and metatarsus were measured daily between the 10th and 21st day of the experiment. Daily relative asymmetry values of bilateral traits were estimated. The hatchability, the weight of the 1-day-old chicks and chick quality were determined. In conclusion, no negative effects of the treatments of the long-term high-thermal environment in the early and late stages of incubation for epigenetic adaptation were determined on the embryo morphology, development stability and weight of the chick. Moreover, regressed hatchability of embryos that were exposed to a long-term high-thermal environment was detected. Especially between the 10 and 18th day, the thermal manipulation considerably reduced the quality of the chicks. Acclimation treatments of high temperature on the eggs from cross-breeding flocks should not be made long term; instead, short-term treatments should be made by determining the stage that generates epigenetic adaptation.

• Publisher: Cambridge University Press,Elsevier Limited,Elsevier
• Subject: acclimation / Acclimatization / adverse effects / Animals / Body Weight / broiler / broiler chickens / Chick Embryo - embryology / Chick Embryo - growth & development / Chick Embryo - physiology / chick quality / Chickens / Chickens - growth & development / Chickens - physiology / chicks / crossing / Eggs / embryogenesis / Embryonic Development / Embryonic growth stage / Embryos / epigenetic adaptation / epigenetics / face / femur / flocks / heat stress / High temperature / Hot Temperature / metatarsus / mortality / Physiology and functional biology of systems / Random Allocation / relative asymmetry / Relative humidity / Research Article / temperature / Thermal stress / tibia