Mammary cancer is one of the most prevalent types of cancer worldwide, affecting millions of individuals each year. Obesity, characterized by excessive accumulation of body fat, has been identified as a significant risk factor for the development and progression of mammary cancer. The impact of a high-calorie diet on mammary tumor development was investigated in Wistar rats induced with N-methyl-N-nitrosourea (MNU). Twenty-eight female rats were randomly assigned to four groups (n=7): WD (Western diet); WD+MNU; SD (standard diet); SD+MNU. The rats had unlimited access to water and food. The WD groups received a high-fat diet (60% of calories from fat), while the SD groups received a standard laboratory diet. Body weight, and humane endpoints were recorded weekly. Lee index, body mass index, and specific rate of body mass gain were calculated. The initial body weights were found to be lower than the final weights (p<0.05), without significant differences observed across the groups (p>0.05). The final body weights were found to be slightly higher in the WD groups (p>0.05). The Lee index and body mass index were similar across the groups (p>0.05). The specific rate of body mass gain was found to be slightly increased in WD groups (p>0.05). No statistically significant differences were observed in humane endpoints. These findings suggest that a high-calorie diet did not significantly influence body weight parameters or humane endpoints in MNU-induced mammary tumors in Wistar rats.

Ana Faustino is Professor at Department of Zootechnics of University of Évora and Researcher at CITAB/UTAD. She holds a Master in Veterinary Medicine and a European PhD in Veterinary Sciences. Animal models of cancer, tumoral angiogenesis and imaging are her main areas of interest. She has collaborating in several Financed Research projects. The results of her works were published in more than 500 publications in several formats. She received several prizes of scientific merit, and highlights and press honors. She has experience in supervising graduate and post-graduate students. She participated in several courses, workshops, international and national meetings. She is editorial member of several scientific journals and reviewer of more than 300 manuscripts. She is Guest Editor of several special issues in Veterinary Animals and in Life.