An environmental assessment of the property took place on 5 March, a week after they were discovered, as part of the investigation into their deaths.
It found rodent faeces, a live rodent, dead rodent and a rodent nest in three garages, in addition to further rodent droppings in two small external houses and three sheds. Traps had also been set up.
There were sightings of rodents, a nest and faeces in two abandoned vehicles or farming machinery in the grounds of the property.
All eight detached outbuildings were within 50 yards (45 metres) of the main house where the couple lived, which itself was "clean with no signs of rodent activity," New Mexico public health officials said in their eight-page report.