Your Pain Is Not My Gain: How the in-utero Experience of Piglets Born From Sows With Lameness Shapes Their Life Trajectory

Abstract

Experiences during gestation can alter the mother’s behavior and physiology, affecting the development of the offspring, including the organization of their brains and emotional system. In livestock, one common challenge for pregnant animals is lameness: a multifactorial condition that causes pain, stress, and compromises welfare. Since pain experienced during gestation can affect offspring development, we aimed to quantify the emotional outcomes of 156 piglets born from sows with lameness during pregnancy. Gait scores of 22 pregnant group-housed sows were assessed six times at two-week intervals. Lameness scores varied from 0 (no lameness) to 5 (most severe lameness score). Saliva samples and behavior were assessed in the sows throughout the pregnancy. Sows were moved to individual farrowing pens and placental tissue was collected for glucocorticoids assessment. At 28 days of age, piglets were weaned, weighed, and grouped by body size and sex. Skin lesions were counted in each piglet on days 28, 29, and 30 after birth. During open field and novel object tests the vocalization and activity levels were evaluated. Piglet data were grouped by the lameness score of the sows as G1 (lameness score 0-1), G2 (lameness score 2-3), and G3 (lameness score 4-5). Data analysis included ANOVA or Kruskal-Wallis tests and pairwise comparisons were performed using Tukey and Kramer (Nemenyi) test with Tukey-Dist approximation for independent samples. G2 piglets were heavier than G3 at weaning. G1 piglets had fewer skin lesions at days 28 and 29 than G2 piglets. Moreover, G1 piglets vocalized more than G2 when they were subjected to the combined open field and novel object test. We did not identify differences in the concentration of placental or salivary glucocorticoids among the sampled sows showing different lameness scores. Lameness in pregnant sows has negative effects on the offspring, affecting weight gain, increasing aggressiveness, altering vocalization during an open field, and novel object tests in piglets.

Lameness in sows and the emotional consequences in the offspring

“…Our data supports previous results where lameness in sows during late pregnancy alters the phenotype of the offspring (Sarmiento et al, 2021). Piglets from lame sows responded behaviorally and physiologically differently when subjected to social challenges or unknown situations than piglets from sows without lameness.…”

Life experiences of boars can shape the survival, aggression, and nociception responses of their offspring

“…Saliva samples for cortisol quantification were collected with buccal swabs (3 cotton swabs, Johnson & Johnson ® ) from piglets in the morning (8 -10h am) on the day of weaning when they were still with the sow and 24 h post-weaning. Afterwards, 50µl saliva samples were analyzed with a cortisol enzyme immunoassay (EIA) (Siegford et al, 2008;Tatemoto et al, 2019a;Bernardino, 2021;de Souza Farias et al, 2021;Sarmiento et al, 2021).…”

“…For all piglets, three pictures were taken daily from each side of their body: face, external ear, and body (Figure 2). At the time of weaning and 24 h postweaning for three consecutive days, totaling 30 images per animal (Guy et al, 2009;Bernardino et al, 2016;Sarmiento et al, 2021). Physical restraint was performed gently following the same protocol to obtain the photos.…”

“…Intergenerational effects have generally been investigated in sows (Bernardino et al, 2016;Tatemoto et al, 2019b;Nery da Silva et al, 2021;Sarmiento et al, 2021). Housing of sows in unstable social environment during pregnancy induced long-term alterations in the nociceptive responses of their offspring (Rutherford et al, 2009;Sandercock et al, 2011).…”

“…Moreover, piglets born from sows with lameness during pregnancy showed altered reactions to noxious mechanical stimuli (Parada et al, 2019). Furthermore, environmental conditions that improved the welfare of gestating sows resulted in modulation of the developmental outcomes of their offspring by altering the aggressive behavioral profile and the number of skin lesions (Bernardino et al, 2016;Sarmiento et al, 2021), changing the hypothalamic-pituitary-adrenal axis responsiveness (Tatemoto et al, 2019a), and impacting the weaning weight of offspring (Sarmiento et al, 2021). Conversely, few scientific studies evaluating the welfare of boars and the consequences on their offspring have been carried out.…”