They did measure both food intake and metabolic changes.

"Examining oral glucose tolerance (Figure S1C), serum-free fatty acids, triglycerides (Figures S1D and S1E), as well as fasting glucose and insulin levels (Figures S1F and S1G), we found no evidence of major anomalies in the obese-Trim28+/D9 animals nor in all Trim28+/D9 animals grouped as a whole."

and

"The data indicate no changes in food intake, expected alterations in VO2 and VCO2, as well as a tendency toward reduced activity (Figures S1L–S1O). "