Progesterone profiles in postpartum dairy cows with inflammatory disorders

Area of Science:

• Reproductive endocrinology in dairy cattle
• Impact of inflammation on ovarian function
• Dairy cow health and fertility

Background:

• Postpartum inflammatory disorders are common in dairy cows.
• Inflammation is suspected to negatively affect reproductive performance.
• Progesterone profiles are critical for successful reproduction.

Purpose of the Study:

• To investigate differences in progesterone profiles between cows with and without early postpartum inflammatory disorders.
• To determine the relationship between inflammatory markers and luteal phase characteristics.
• To explore potential mechanisms linking inflammation to reduced fertility.

Main Methods:

• Prospective cohort study of 708 dairy cows.
• Assessment of clinical health disorders, serum haptoglobin (Hp), and endometritis.
• Progesterone (P4) measurement twice weekly from 35 to 70 days in milk (DIM) to analyze luteal phase (LP) parameters.

Main Results:

• Cows with inflammatory disorders (INFLAM) exhibited prolonged LPs (67% vs. 37%) and longer average LP length (17 vs. 15 days).
• INFLAM cows had lower P4 concentrations during the LP, including peak P4 (6.9 vs. 8.2 ng/mL).
• Inflammation was associated with delayed luteolysis in multiparous cows.

Conclusions:

• Postpartum inflammation in dairy cows is linked to altered luteal function, characterized by prolonged LPs and reduced P4.
• These luteal function alterations represent a potential pathway connecting postpartum health disorders to reduced fertility.
• Early identification and management of inflammation may be crucial for improving dairy cow reproductive success.