Growth rate estimation is important to understand the flow of energy and nutrient elements in an ecosystem, but it's remained challenging, especially on microscopic organisms. In this study, we proposed four growth rate indices that use mRNA abundance ratio between nuclear and mitochondrial genes: (1) total nuclear and mitochondrial mRNA ratio (Nuc:Mito-TmRNA), (2) nuclear and mitochondrial ribosomal protein mRNA ratio (Nuc:Mito-RPmRNA), (3) gene ontology (GO) terms and total mitochondrial mRNA ratios and (4) nuclear and mitochondrial specific gene mRNA ratio. We cultured Daphnia magna under different food concentrations and temperatures and manipulates its growth rate. Total RNA was extracted using RNeasy Plus Micro kit, and mRNA were isolated using NEBNext Poly(A) mRNA magnetic isolation module, and finally RNA-Seq libraries were constructed from each individual using NEBNext Ultra II RNA Library Prep Kit.