[Effect of lighting on various biochemical indicators in the plasma of chickens]

In six experimental series involving all seasons of the year, the author compared the influence natural illumination of medium intensity 82.8 lux (max. 400 lux) with that of artificial illumination of 47.7 lux used alternatively for 3 hr and 1 hr darkness during the day cycle with 5- and 8-week-old chickens in relation o sex. The influence of differentiated illumination on body weight as well as on biochemical indicators of blood plasma was studied. A significantly higher cholesterol level in the plasma of chickens subjected to artificial illumination in the 5th week of age (82.4 mg% and 74,4 mg%) was found, whereas in the 8th week this level was considerably lower than in natural illumination, respectively 92.4 mg% and 101.5 mg%. No significant differences in AP and AlAT activity in the chicken plasma was found with different illumination. In 5-week-old chickens significantly higher AspAT activity was found with artificial illumination--362.1 K units and 327.7 K units, whereas in the 8th week the activity to this enzyme was significantly lower than with natural illumination--246.1 K units and 324.4 K units. Significant differences were also found in the level of total protein and albumins with regard to the kind of illumination.