Systematic metabolomics characterisation of various research models such as rodents, chickens, pigs, humans and horses have been published in the past (Claus et al. 2008; Le Roy et al. 2016; Martin et al. 2007; Merrifield et al. 2011; Ndagijimana et al. 2009; Holmes et al. 1997; Escalona et al. 2015; Mora-Ortiz et al. 2019), but to date, a comprehensive metabolic phenotyping of the leptin receptor defective (db/db) T2D mouse model: BKS.Cg-Dock7 < m > +/+ Lepr < db >/J is missing. Here, LEPR is linked to type 2 diabetes mellitus.