Abstract
AimThis study aimed to examine the effects of feeding or abdominal brushing on the release of the hormones oxytocin, ACTH and cortisol during milking in dairy cows.MethodsTwelve cows in early lactation were used (2 × 2 factorial experimental design), testing the effects of two types of sensory stimulation during milking over a 3 day period; feeding concentrate or manual abdominal brushing (1 stroke/s). Blood samples for hormone analyses were collected at time at −15, −1, 0 (onset of cluster), every min for 8 min, at 10, 12, 14, 16, 30, and 60 min. Hormone levels were assayed and AUC was calculated.ResultsMilking was associated with an immediate and significant rise of oxytocin. When milking was combined with feeding, significantly higher levels of oxytocin were observed at 2 and 4 mins (p < 0.05). No effect of brushing on oxytocin levels was observed. Milking alone was associated with a significant rise of ACTH levels. Feeding in connection with milking reduced the immediate rise of ACTH levels (p < 0.05) and AUC (p < 0.02), whereas no effects of brushing were found. Milking caused a progressive rise of cortisol levels. Concomitant feeding did not influence cortisol levels, whereas brushing significantly decreased cortisol levels at 1, 5 and 14 mins after onset of milking (p < 0.05).ConclusionFeeding increases oxytocin release in response to milking and decreases ACTH levels. Abdominal brushing did not influence these variables, but decreased cortisol levels. These data demonstrate that activation of afferent vagal nerve fibres and of cutaneous sensory nerves originating from the abdominal skin in front of the udder influence milking related hormone release differently.
Highlights
The data from the present study represent a subset of results from a study in which the role of feeding and brushing of the abdominal area during milking on the release of hormones released during milking and on milk yield was studied
When milking was combined with feeding, a significantly higher oxytocin concentration was obtained at 3 min (P < 0.05) and a tendency to higher levels was obtained at 4 min after start of milking compared to milking alone)
ACTH levels were significantly lower at the onset of milking and at 2, 3, 4, and 5 min after onset of milking (P < 0.05) in the feeding group (Table 2)
Summary
The data from the present study represent a subset of results from a study in which the role of feeding and brushing of the abdominal area during milking on the release of hormones released during milking and on milk yield was studied. Oxytocin released within the brain stimulates different types of social interactive behaviours and bonding, induces calmness, increases nociceptive thresholds and induces anti-stress like effects such as a decrease of the activity of the HPA axis and of the sympathetic nervous system, which is reflected by, e.g., reduced plasma cortisol concentrations, blood pressure and heart rate (as reviewed by Uvnäs-Moberg, 1998, 2014, 2015; Uvnäs-Moberg and Petersson, 2005). Oxytocin is released into the circulation in response to milking to induce milk ejection in dairy cows (for review see Bruckmaier and Blum, 1998). Social interactive behaviours and anti-stress effects are induced in connection with milking suggesting that oxytocin is released from neurons originating within the brain during milking (Johansson et al, 1999a,b)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
