Environmental and transition stress in multiparous Holstein cows

Hodnik, Jaka Jakob (2026) Environmental and transition stress in multiparous Holstein cows. MVM(R) thesis, University of Glasgow.

Abstract

Cows are exposed to a range of environmental and physiological stressors that can affect their welfare, behaviour, milk production, and reproduction. Calving is a particularly critical phase in the dairy production cycle, characterised by significant physiological demands. During this period, reduced feed intake coincides with increased energy requirements for foetal growth and the onset of lactation, predisposing cows to metabolic disorders and diseases. This can negatively impact welfare, productivity, and longevity. Stress is commonly assessed using behavioural observations or biomarkers such as cortisol, though these approaches may be subjective or invasive. Heart rate variability (HRV) provides a non-invasive alternative for evaluating autonomic nervous system activity and physiological stress.
This thesis aimed to assess physiological stress in cows -10 to +7 days around calving using HRV and to investigate associations with transition diseases, cow-level factors, and calf characteristics. Clear temporal changes in HRV were observed. Heart rate increased as calving approached, peaking shortly before parturition, while vagally mediated HRV parameters showed a U-shaped pattern with a nadir around calving. These findings indicate elevated stress during the periparturient period followed by recovery. Carrying twin calves or dairy-sired calves was associated with HRV patterns suggesting greater stress. In contrast, post-partum disease, body condition score, rumen fill, and lactation number showed no significant association with HRV within the study period.
A second objective was to evaluate environmental conditions within a commercial dairy housing system using both commercial and custom-built monitoring devices. Results from the commercial sensors revealed considerable spatial and temporal variation in microclimatic conditions within the sheds. Sheds were typically warmer and less humid than outside, yet the Temperature Humidity Index (THI) frequently exceeded the threshold of 62, particularly in high-density areas such as the collecting yard. Custom-built sensors performed comparably to commercial devices for temperature and humidity but were less reliable overall, particularly for light intensity.
In conclusion, HRV is a practical and sensitive non-invasive tool for assessing physiological stress in dairy cows around calving. Stress levels peak during the immediate peri-calving period, with calf characteristics influencing maternal stress. Environmental monitoring demonstrated variability within housing, with higher-risk areas identified. These findings highlight the potential for targeted interventions, such as cooling systems in high-density areas, and support the integration of HRV and environmental monitoring into precision livestock farming to improve cow welfare, management, and productivity.

• Item Type: Thesis (MVM(R))
• Qualification Level: Masters
• Additional Information: Supported by funding from the University of Glasgow Vet Fund and MVLS Academic Returners Scheme grant.
• Subjects: S Agriculture > SF Animal culture > SF600 Veterinary Medicine
• Colleges/Schools: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Funder's Name: University of Glasgow Vet Fund, MVLS Academic Returners Scheme
• Supervisor's Name: Viora, Dr. Lorenzo, Vazquez, Mr. Richard, Evans, Dr. Neil and Hill, Dr. Davina
• Date of Award: 2026
• Depositing User: Theses Team
• Unique ID: glathesis:2026-86129
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 16 Jul 2026 10:58
• Last Modified: 19 Jul 2026 06:36
• Thesis DOI: 10.5525/gla.thesis.86129
• URI: https://theses.gla.ac.uk/id/eprint/86129