Kyphotic response alterations in perinatally underfed lactating dams

In the rat, the mother provides the newborns with plenty of breastfeeding, sensory stimulation, and protection for survival. In this review, we emphasized the deficits in the kyphotic response of F1 lactating dams with pre-and neonatal undernutrition that interfere with the pups ' sucking activity and physical and brain development. One group (F0) compared the effects of gestational food restriction (50%, G6-G12; 30%, G13-G19) and postnatal undernutrition of F1 pups to investigate their physical development. To analyze the impact of early undernutrition on the physical development of F1 rats, prenatally underfed subjects were placed daily in an incubator (12 h) or by the rotation (12 h) of two dams, one with nipples-ligature (days 1-24) between litters. Weaning was at 25 days old, and rats followed a balanced diet until 90 days, when pregnant F1 dams were tested for the kyphotic response. Skull, nose-coccyx, tarsus-metatarsus, phalange lengths, bitemporal axis, body weight, and eyelid-opening were measured in F1 rats (days 5-30). Pre-and neonatally undernourished F1 subjects exhibited body weight and skeletal deficits at most of the ages than controls. Furthermore, the functional evaluation of the nose-coccyx and limb musculature for the kyphotic posture elicited in F1 mothers by active pups (days 4, 12) indicated that undernutrition interfered with the kyphotic response. Functionally, this posture disrupted c-Fos immunostaining at the periaqueductal gray of F1 dams and the pups ' body growth, brain sensory activity, and possibly later cognition. The findings may be relevant to understand long-term effects in adolescent human mothers, usually with short stature and poor interest in newborn breeding.