Porcine mastitis-metritis-agalactia (MMA) syndrome: mammary gland responsiveness to oxytocin given to healthy sows during lactation
Sims, M.H.; Eiler, H.
American Journal of Veterinary Research 40(8): 1104-1106
1979
ISSN/ISBN: 0002-9645 PMID: 575026 Document Number: 152079
Mammary gland response to oxytocin was measured from changes in intramammary pressure of healthy sows given 40 U i/m once a week for the first 8 weeks of lactation. Recordings of pressure changes were expressed as mean area (cm2) under the trace at each 10-minute interval over 30 minutes after oxytocin injection. During the second week of lactation, there was a 55.3% increase in response to oxytocin (25.1 plus or minus 4.2 cm2/10 minutes) as compared with the first week (13.9 plus or minus 2.2 cm2/10 minutes). The response decreased from the second to the eight week. Since the frequency of mastitis-metritis-agalactia in sows is particularly high during the first week of lactation, a low response of the mammary gland to oxytocin may be a contributing factor.