Oxytocin and cortisol in goat milk during early lactation under different housing conditions: a descriptive study

This Brief Research Report descriptively characterizes oxytocin (OT) and cortisol (CORT) concentrations in milk of multiparous dairy goats (n = 20) during early lactation and explores associations with housing context and early kid growth within a Positive Animal Welfare framework. Does and their kids were housed in two indoor pens (low density, LD; 1.39 m² per doe; high density, HD; 0.89 m² per doe).Milk samples were collected weekly over four consecutive weeks during machine milking and kid suckling. Mean milk OT concentrations were 296.7 ± 133.6 pg/mL during milking and 284.9 ± 119.7 pg/mL during suckling, whereas mean CORT concentrations were 0.86 ± 0.72 and 0.75 ± 0.71 μg/dl, respectively. OT concentrations were highest in week 1 and declined over time, while CORT showed no consistent temporal pattern. Does in LD showed higher OT and lower CORT than HD during both milking (OT: 336 ± 141 vs. 257 ± 116 pg/ml; CORT: 0.72 ± 0.63 vs. 1.00 ± 0.77 μg/dl) and suckling (OT: 309 ± 123 vs. 260 ± 111 pg/ml; CORT: 0.64 ± 0.62 vs. 0.86 ± 0.76 μg/dl). Higher maternal OT and lower CORT were associated with greater kid body weight at 51 days of age, whereas twin-rearing does showed higher CORT and lower kid weight than single-rearing does. These findings demonstrate the feasibility of repeated OT and CORT measurement in goat milk under routine farm conditions, but interpretation is limited by small sample size, lack of pen replication, and incomplete assay validation.