Assessments of Motor Abnormalities on the Grid-Walking and Foot-Fault Tests From Undernutrition in Wistar Rats

• Published in: Journal of motor behavior Vol. 48; no. 1; pp. 5 - 12
• Main Authors: Barbosa, Everton Horiquini, Vallim, José Henrique, Lachat, João-José, de Castro, Vera Lucia S. S.
• Format: Journal Article
• Language: English
• Published: United States Routledge 01-01-2016; Taylor & Francis Inc
• Subjects: Anatomy; Animals; Animals, Newborn - physiology; Body Weight; Breastfeeding & lactation; developmental milestones; early undernutrition; Feet; Female; foot-fault test; grid-walking test; Male; Malnutrition; Malnutrition - complications; Malnutrition - physiopathology; Motor ability; motor development; Motor Skills Disorders - etiology; Motor Skills Disorders - physiopathology; Muscle Strength - physiology; Muscular Strength; Neurodevelopmental Disorders - etiology; Neurodevelopmental Disorders - physiopathology; neurological reflexes; Nutrition; Physical Fitness; Pollution; Rats; Rats, Wistar - physiology; Reflex - physiology; Reflex, Startle - physiology; Rodents; Walking; Walking - physiology; foot-fault test; motor development; neurological reflexes; developmental milestones; early undernutrition; grid-walking test
• ISSN: 0022-2895; 1940-1027
• DOI: 10.1080/00222895.2015.1024824

This study was designed to verify whether different lactation conditions influenced nervous system development. The authors used motor tasks to verify changes in exploratory activity and muscle strength of weaned rats from different litter sizes and evaluated the applicability of the grid-walking test for assessing motor abnormalities caused by undernutrition. Alterations in litter size during the suckling period perturbed the nutritional status of pups, which exhibited body weight differences between the groups. Large-litter (L) pups showed significant delays in achieving developmental milestones and neurological reflexes compared to the small-litter (S) and medium-litter (M) pups. The S, M, and L group pups exhibited similar exploratory responses and muscle strength. In the grid-walking and foot-fault tests, the L group pups traveled shorter distances and, consequently, had less footsteps. However, the percentages of foot faults in the L group were higher than S and M groups. These results reflect delayed maturation of structures responsible for sensorimotor responses, such as the cerebellum, because much cerebellar maturation takes place postnatally. This is the first study to report that early undernutrition in pups resulted in suboptimal performances on the grid-walking and foot-fault tests and that the former test was sensitive to alterations caused by nutritional deficiency.