Cerium Chloride Improves Protein and Carbohydrate Metabolism of Fifth-Instar Larvae of Bombyx mori Under Phoxim Toxicity

The organophosphorus pesticide poisoning of the silkworm Bombyx mori is one of the major events causing serious damage to sericulture. Added low-dose rare earths are demonstrated to increase resistance in animals. However, very little is known about whether or not added CeCl 3 can increase resistance of silkworm to phoxim poisoning. The present findings suggested that added CeCl 3 to mulberry leaves markedly increased contents of protein, glucose and pyruvate, and carbohydrate metabolism-related enzyme activities, including lactate dehydrogenase, succinate dehydrogenase and malate dehydrogenase, and attenuated free amino acids, urea, uric acid and lactate levels and inhibited the protein metabolism-related enzymes activities, such as protease, alanine aminotransferase and aspartate aminotransferase in the haemolymph of B. mori , under phoxim toxicity. These findings suggest that added CeCl 3 may improve protein and carbohydrate metabolisms, thus leading to increases of growth and survival rate of B. mori under phoxim stress.