Overview of progesterone profiles in dairy cows

Area of Science:

• Veterinary Science
• Reproductive Biology
• Animal Science

Background:

• Estrus cycle variability in cows impacts reproductive efficiency.
• Understanding progesterone profile dynamics is crucial for estrus detection and fertility management.
• Existing methods for analyzing progesterone profiles lack standardized templates for natural variations.

Purpose of the Study:

• To characterize the variability in progesterone profiles during bovine estrus cycles.
• To develop data-driven templates for typical progesterone cycle shapes and features.
• To establish a foundation for improved reproductive assessments in cattle.

Main Methods:

• Analysis of 1006 bovine estrus cycles using daily milk progesterone data.
• Smoothing of progesterone time series using a median kernel.
• Clustering analysis of luteal-like phases (LLP) based on shape distance within quantiles.

Main Results:

• Most progesterone profiles exhibited a typical shape, even exceeding 24 days.
• Cycles in quantiles Q2 and Q3 showed steeper slopes and higher peak progesterone than Q1 and Q4.
• Normalized profiles demonstrated similar shapes across quantiles, with defined differences in steepness and height between quantiles.

Conclusions:

• Established templates for progesterone profile shapes and features based on data-driven clustering.
• Demonstrated quantifiable differences in LLP steepness and height across quantiles.
• Proposed a profile clustering procedure for classifying progesterone profiles without arbitrary rules, enabling more accurate assessments.