Effect of Incubator Temperature and Oxygen Concentration at the Plateau Stage in Oxygen Consumption on Turkey Embryo Muscle Growth and Development

Abstract

It was hypothesized that incubator temperature and oxygen concentration affect embryo muscle development. Turkey eggs were incubated until the 24th day of development. At the beginning of the 24th day, the eggs containing viable embryos were randomly divided into 4 groups immediately prior to the plateau stage in oxygen consumption. Four experimental cabinets accommodating approximately 100 eggs were used for the actual hatching process. Each cabinet operated at predetermined temperatures (TEM) and oxygen concentrations (O₂) in a 2 TEM (36° and 39°C) x 2 O₂ (17 and 23%) factorial arrangement. At 27 and 28 days of development, immediately following the plateau stage, 10 embryos or poults were sampled from each of the 4 cabinets. Blood was obtained following decapitation. From each carcass the pipping (musculus complexus), breast (pectoralis thoracicus) and thigh muscles (gastrocnemus) were collected. Muscles were placed into an appropriate volume of 7% perchloric acid preparatory to assaying for glycogen and lactate. Five birds were sampled for histological analyses of muscle fibers. Plasma Creatine Kinase (CK) and lactate dehydrogenase (LDH) activities were measured. TEM and O₂ affected muscle growth differently. High TEM and O₂ affected pipping and thigh muscle weights but not that of the breast muscle. Only TEM affected breast muscle weights. Muscle function was affected differently when embryos were exposed to TEM and O_2. The CK and LDH activities were also affected at 27 days 39°C causing elevated CK and LDH activities compared to 36°C. At 28 days, only CK was affected as 39°C elevated CK activity in the 23% oxygen environment but not in the 17% environment. Thus, incubator conditions may affect muscle development and function in poult embryos