Effect of Simulated Microgravity on Metabolite Concentrations in the Muscles and Liver of Developing Japanese Quail Chicks

Abstract

Hypodynamy is the most frequently used ground-based model to study the negative consequences of microgravity on an animal organism. The objective of the current experiment was to examine the influence of hypodynamy on the growth and development of the breast muscle, thigh muscles and liver in female Japanese quail chicks from 3 to 56 d of age. Samples of muscles and liver were obtained at 1, 14, 28, 42 and 56 d; the variables studied were: weight (g), relative weight (%), dry matter (mg/g) and content of total proteins, total lipids and glycogen (mg/g). The actual weight of breast muscle, thigh muscles and liver gradually increased with age of quail in both groups. However, the experimental birds exposed to hypodynamy showed a reduction in growth relative to age-matched control. At the end of testing, the body weight of the hypodynamy group was significantly lesser than that of control (P < 0.05). The control birds had also significantly heavier breast muscle than those of experimental group. Similarly, the dry matter and total lipid content in both muscles and liver of control group was significantly increased (P < 0.05). On the contrary, the differences in the content of total protein and glycogen in muscles and liver of both groups were not significant at the end of experiment. These results provide further evidence that, although hypodynamy affects the examined variables of selected skeletal muscles and liver, the female Japanese quail is able to develop under conditions of simulated weightlessness.