RESUMEN
BACKGROUND: Flaxseed oil (FO) is an alpha linolenic acid source important for growth and body development. However, there is little literature on the role of FO in critical stages of bone development and formation. OBJECTIVE: This study evaluated the influence of a diet containing FO on rat femurs. METHODS: After birth, mothers and pups were divided into control and flaxseed groups (n = 6 pups each) fed diets containing 7% soybean oil (C) or 7% FO. At 21 days, pups were weaned and separated from the mothers, and control or experimental diets were continued. At 67 days, the following were analyzed: osteocalcin and osteoprotegerin (OPG) levels, bone mineral density (BMD) and content, and bone area; the dimension, BMD, head radiodensity, and biomechanical proprieties of the right femur; and histomorphometric parameters of the left femur. RESULTS: Compared to the C group, the FO group presented (p < 0.05) a lower body mass (-3.7%) and medullary area (-10.1%) and higher osteocalcin (+36.7%), OPG (+52.5%), femur width (+3.8%), absolute mass (+2.3%), femur BMD (+3.6%), head radiodensity (+6.1%), maximum force (+7.4%), breaking strength (+17.3), and cortical thickness (+7.0). CONCLUSION: The FO diet contributed to femur quality in healthy male Wistar rats.