2.10 Calf health scoring Similar to that reported by (Sinnott et al., 2024) calf health scores were assigned on an individual basis twice-weekly, on two non-consecutive days, from birth to weaning. Calves were scored on 11 different aspects of health as outlined by (Barry et al., 2022) which were as follows: demeanor, mobility, interest in surroundings, temperature, ears, eyes, nasal discharge, fecal consistency, cough, naval, and joints. Each individual aspect received a score from 0 to 3; 0 represented normal and 3 represented the most severely affected. Following each health-scoring assessment, results were relayed to the farm manager to allow treatments to be provided if necessary. Any illness episodes were treated appropriately by farm personnel or a veterinarian, depending on the severity or complexity of the illness. Type of treatment and duration of administration were recorded. When a calf was identified, through health scoring, as necessitating veterinary treatment a saliva sample was collected. A corresponding healthy calf was also identified and simultaneously sampled. Saliva swabs were collected as described by (Rubio et al., 2021) using a foam swab (Sterile Oral Swab Mouthcare, Medguard Healthcare) which calves chewed for 1 min. Lastly, saliva were extracted from the swab and were ready for testing.