Experimental diet based on the foods listed in the family budget survey is more detrimental to growth than to the reflex development of rats

Abstract

Objective: The present study assessed the pregnancy and lactation performances of rats fed an experimental diet based on the foods listed in the Family Budget Survey (Pesquisa de Orçamento Familiar) 2002/2003 and the impact of said diet on the growth and development of the pups until weaning. Methods: Wistar (n=12) rats were randomly divided into two groups: a control group (control group, n=6) fed a commercial chow (Labina®, Brazil) and an experimental group (n=6) fed the Family Budget Survey diet during the entire pregnancy and lactation period. All animals had free access to food and water during the entire study period. Results: The Family Budget Survey diet increased the duration of pregnancy (control group=21.00±0.00; POFG=21.57±0.55, p=0.025) and made the dams lose weight during the lactation period (control group=27.92±18.47g; POFG=-15.66±16.90g). The Family Budget Survey group presented low food, energy and nutrient intakes during pregnancy, which became even lower during lactation. Pups from Family Budget Survey dams presented lower body weight at weaning (control group=52.38±4.49g; POFG=39.88±2.78g, p=0.001) and lower nose-to-anus length (control group= 117.37±0.64mm; POFG=125.62±0.96mm, p=0.001). However, some physical milestones and reflexes occurred earlier, such as the placing response reflex [control group= 12.00 (9.00-15.00) days; POFG=9.50 (9.00-14.00) days] aerial righting reflex [control group=18.00 (17.00-20.00) days; POFG=16.00 (13.00-18.00) days] and unfolding of the external ear [control group=3.00 (3.00-3.00) days; POFG=2.00 (2.00-3.00) days]. Conclusion: The Family Budget Survey diet seems to be more detrimental to the physical growth of the pups than to their brain growth, according to the assessed reflexes and physical milestones and measures. This may be due to the low protein content of the diet for rat reproduction and growth combined with adequate fat and essential fatty acid contents. Providing an adequate amount of protein to the Family Budget Survey diet may normalize pup growth.