Evaluating The Precocial-altricial Axis of Motor Skill at Birth in A Preterm Pig Model
Title
Evaluating The Precocial-altricial Axis of Motor Skill at Birth in A Preterm Pig Model
Creator
Jesse W Young
Christopher J Mayerl
Alekhya Mannava
Claire Lewis
Tianhui Fan
Manas Nair
Christopher Mamone
Nicole M Schapker
Angela M Mossor
Rebecca Z German
Publisher
Integrative and Comparative Biology
Date
2023 Apr 6
Description
The pace of locomotor development is a critical component of lifetime evolutionary fitness. Developmental researchers often divide species into two broad categories based on functional competence at birth: precocial infants who can independently stand and locomote soon after birth versus altricial infants who are either incapable of independent movement or can only do so in a rudimentary manner. However, investigating the lower level neuromotor and biomechanical traits that account for perinatal variation in motor development is complicated by the lack of experimental control inherent to all comparative analyses. Precocial and altricial animals often differ along a host of dimensions that can obfuscate the specific factors controlling motor development per se. Here, we propose an alternative approach of examining locomotor development in a nominally precocial species-the domestic pig (Sus scrofa)-in which gestation length has been experimentally manipulated, thereby creating "functionally altricial" cohorts for comparison. We used standard biomechanical testing to evaluate balance and locomotor performance in preterm pigs born at 94% full-term gestation (N = 29 individuals) and compared these data to a similar dataset on age-matched full-term piglets (N = 15 individuals). Static balance tests showed that preterm pigs were characterized by increased postural sway, particularly in the fore-aft (anteroposterior) direction. Locomotor analyses showed that preterm piglets tended to take shorter, more frequent strides, use higher duty factors, and preferentially choose gait patterns that ensured they were supported by at least three limbs during most of the stride cycle, though differences between preterm and full-term animals were often modulated by variation in locomotor speed. Morphometric analysis showed no differences in relative extensor muscle mass between preterm and full-term animals, suggesting that neurological immaturity might be more determinant of preterm piglet motor dysfunctions than musculoskeletal immaturity per se (though much work remains to be done to fully document the neuromotor phenotype of the preterm infant pig model). In many ways, the postural and locomotor deficits shown by the preterm piglets paralleled the locomotor phenotype of altricial mammals. Overall, our study demonstrates the utility of a "within-species" design for studying the biomechanical correlates and neuromotor basis of evolutionary variation in motor skill at birth.
Source
doi: 10.1093/icb/icad013. Online ahead of print.
Language
English
Citation
Jesse W Young et al., “Evaluating The Precocial-altricial Axis of Motor Skill at Birth in A Preterm Pig Model,” NEOMED Bibliography Database, accessed April 25, 2024, https://neomed.omeka.net/items/show/12306.