To assess the effect of flaxseed on rat milk creamatocrit and its contribution to offspring weight gain during lactation.

The study was conducted with 22 Lister Hooded rats divided into two groups: Control Group (CG, n = 11), which received a casein-based diet with 17% protein, and Flaxseed Group (FG, n = 11), which received a 25% flaxseed diet supplemented with 14% casein, totaling 17% protein. Food consumption was controlled per individual cage and litter size. Maternal milk creamatocrit and offspring weight variation until weaning age were also evaluated.

FG was similar to CG concerning food intake (FG = 76.46±31.87 g; CG = 76.7±33.36 g; p = 0.9613) and equivalent to CG concerning litter size (FG = 4.94±2.34; CG = 5.5±3.19; p = 0.435). The same was found for milk fat content (FG = 18.4±4.76; CG = 15.3±6.03; p = 0.204) and total energy value (FG = 212.92±46.4; CG = 181.1±60; p = 0.1964). FG was similar to CG both in offspring body weight at weaning (FG = 37±6.96 g; CG = 32.6±7.5 g; p = 0.1817) and in weight gain (FG = 31.8±7.0 g; CG = 27.7±7.5 g; p = 0.2104).

A total of 25% flaxseed promoted an adequate offspring growth.