Revista Brasileira de Medicina do Esporte
Print version ISSN 1517-8692
NERY, Cybelle da Silva et al. Murinometric evaluations and feed efficiency in rats from reduced litter during lactation and submitted or not to swimming exercise. Rev Bras Med Esporte [online]. 2011, vol.17, n.1, pp. 49-55. ISSN 1517-8692. http://dx.doi.org/10.1590/S1517-86922011000100010.
INTRODUCTION: Overfeeding in early life can persistently modify consumption and body weight. Adoption of exercise is one useful strategy to prevent excessive weight gain. OBJECTIVE: to assess body growth and feed efficiency in rats from reduced litters during lactation. METHODS: On day 3 of life, litters were formed with 4 (GN4) or 10 animals (GN10) (n = 25). When weaned, Wistar male rats were kept in individual cages and at day 60 (± 2) they were divided into sedentary (SED) and exercised (NAT), forming thus four groups: GN4SED; GN10SED; GN4NAT and GN10NAT. Assessment consisted of weight, weight gain and specific rate of weight gain, epididymal fat, Body Mass and Lee Indices, consumption and feed efficiency, blood glucose and lactemia. RESULTS: At day 21, GN4 had body weight 52% above GN10 (P = 0.001). However, at days 30 and 60, their weight was not different. At the end of the period, GN10NAT showed lower weight (356.82 ± 23.04) that GN10SED (409.28 ± 17.30), but GN4NAT was heavier (417.85 ± 37.91) than GN4SED (413.69 ± 57.45) and GN10NAT. GN4 presented higher rate of weight gain during lactation, but slower after weaning. Regardless of litter size, rate of weight gain reduces as age progresses. At the end of this period, blood glucose, total and relative epididymal fat, and Lee and BMI indices did not differ between groups. Pre and post-exercise lactate values are consistent with moderate effort. In periadolescence, GN4 showed lower food intake, but with no differences in adulthood. CONCLUSION: Reduced litter during lactation did not affect body weight or food intake persistently. However, the swimming protocol was effective in reducing weight gain in control animals, but not in animals from reduced litters.
Keywords : anthropometry; physical activity; food intake; rat pups.