Telomere Dynamics and Cortisol Response in Grazing Goats: Preliminary Insights Into Welfare Monitoring

This study evaluated telomere length (TL) and serum cortisol concentration (SCC) as complementary stress biomarkers in grazing dairy goats. Twenty pluriparous "Camosciata delle Alpi" goats were monitored under extensive conditions at three 15-day intervals. Milk-derived DNA was used to assess TL by quantitative PCR; SCC was measured by enzyme immunoassay. Environmental parameters were recorded throughout the trial. SCC rose from 5.84 to 12.93 ng/mL at the second sampling, coinciding with adverse weather, and returned to baseline thereafter. TL decreased from 1.21 to 0.92 (telomere-to-single-copy gene-T/S ratio) before recovering to 1.16. TL was negatively correlated with humidity and dew point, and positively correlated with rainfall, suggesting that moisture-related stressors influence TL dynamics. These findings indicate that acute environmental challenges induce transient telomere shortening. Integrating TL and SCC provides a more comprehensive welfare assessment, with TL emerging as a promising non-invasive genomic biomarker for stress and resilience in pasture-based livestock systems.