We report the effect of several parameters on the efficiency of recovery of DNA from animal bones. The effects of preheating the samples (at either 60degreesC or 100degreesC) at different intervals (from 1 h to overnight) in different media (water, 0.5 m ethylenediaminetetraacetic acid (EDTA), or 0.5 m EDTA + 0.05% sodium dodecyl sulfate (SDS) were investigated. The effect of slight (5 min) or intense (30 min) pretreatments with ultrasound was also evaluated. Several different treatments with proteinase K (ranging from 200 to 800 mug, and lasting from 1 to 3 h) at 65degreesC were also considered. Additionally, two different DNA extraction methods (based on silica resins and purification columns, respectively) were evaluated. The recovery of DNA from the samples was 40% higher when the bones were preheated in 0.5 m EDTA at 60degreesC for 1 h, this being followed by treatment with 800 mug of proteinase K for 3 h. The DNA thus obtained was successfully amplified by polymerase chain reaction (PCR) using a set of primers specific to a 359 bp region of the mitochondrial cytochrome b gene, and the species of origin were identified by visualizing the restriction fragment length polymorphism (RFLP) with the endonucleases Pa/l and Mbol.