The Effect of Different Storage Temperatures over Time on the pH of Mammary Gland Secretions in Periparturient Mares.

This research investigates how storage temperatures affect the pH level of mare Mammary Gland Secretions (MGS) pre and postpartum. It also examines the concentrations of various electrolytes in the MGS and how they fluctuate throughout the foaling process. The study found that most mares had an acidic pH at foaling, which changed to neutral and slightly alkaline in the postpartum period. Variations in storage temperatures had minimal influence on MGS pH, except at a pH of around 7.5 which shifted to about 8 after storage.

Methodology and Objectives

• The study’s first goal was to measure the pH and electrolyte (calcium, magnesium, sodium, potassium) levels in the MGS of mares pre and post-foaling.
• The second aspect was to track the changes in mare milk pH in the first week after foaling.
• An additional aim was to assess the effect of different storage temperatures on the pH of pre-foaling MGS.
• Twenty-three mares in late stages of gestation were closely monitored, and their MGS collected for pH measurement and further evaluation.
• For the storage temperature evaluation, pH levels were checked at set intervals after the samples were stored.

Hypotheses and Findings

• Two hypotheses were tested: one, that all mares would display acidic pH and altered electrolyte concentrations irrespective of pre-foaling levels; second, that the pH of pre-foaling MGS would change with storage temperature and time depending on initial values.
• Results demonstrated that most mares manifested a sodium-potassium inversion and acidic pH at the time of foaling.
• Investigations revealed that in the early postpartum days, milk pH was neutral and eventually became slightly alkaline, the clinical significance of which remains undetermined.
• Contrary to the second hypothesis, changes in storage temperatures showed minimal effect on MGS pH except for a certain pH value, around 7.5, which notably increased following storage to approximately 8.

Significance of the Study

• This research is the first attempt to address such physiological and practical aspects concerning the pH of mare MGS during the periparturient period.
• This provides valuable understanding about the intricate hormonal, physiological, and biochemical changes occurring in mares around the time of foaling and how they’re influenced by external factors such as storage temperature.

The findings provide an important basis for further investigation into the clinical implications of such changes and their impact on the health and welfare of mares and their offspring.