Despite having sperm with good motility (forward movement) and morphology (cell shape), one out of every four boars experience a conception rate of less than 80%. The issue mirrors human fertility challenges with one out of eight couples struggling with infertility, and one-third of those cases are attributed to male factors, according to the National Institute of Health.
“Pigs and cattle are species we have plenty of oocytes and sperm cells available for, allowing us to conduct in vitro fertilization research,” says Karl Kerns, Iowa State University assistant professor of animal science in a recent article. “They also are effective models for human reproduction compared to rodents, who do not model the human as well genetically or phenotypically at the cellular level.”
He dedicates his research efforts to pigs and cattle.
Kerns’ Lab specializes in molecular reproductive physiology with a focus on understanding and enhancing livestock sire fertility. The lab is equipped with state-of-the-art facilities, including andrology and molecular biology labs as well as an in vitro fertilization (IVF) lab. The IVF lab has computer-assisted semen analysis and time-lapse fluorescent microscopes to image-based flow cytometry paired with deep learning, artificial intelligence analysis methods and sorting flow cytometry.
The lab’s goal is to enhance reproductive efficiency by analyzing sperm quality and identifying biological markers that influence fertility rates. The process involves sorting sperm cells using advanced flow cytometry technology. The sorter system uses microfluidics and lasers to analyze and sort cells based on fluorescence-marked biomarkers.
“We can track thousands of cells per second, identifying key fertility indicators and sorting them accordingly,” Kerns says.
The process allows for an in-depth analysis of fertility potential and production capabilities.
Kerns’ team employs both positive and negative biomarkers to evaluate sperm quality. Positive biomarkers are generally considered good and reflect increased chances of conception, while negative biomarkers can indicate compromised fertility potential.
The team also assesses mitochondrial activity, zinc signatures and protein detection, all of which assist the lab in detecting and analyzing both healthy and unhealthy sperm.
Ian Shofner, a third-year doctorate student in mammalian reproductive physiology, focuses on artificial intelligence (AI) and developing models that predict sperm fertility metrics in the Kerns Lab.
“Currently, male fertility diagnostics are lacking in accuracy, and my work aims to improve these predictions for better assessments of male fertility in mammals,” Shofner explains. “With this, we intend on enabling the industry to make cost-effective AI solutions for fertility diagnostics using affordable brightfield microscopy technology.”
Tyler Weide, a third-year doctorate student in the interdepartmental genetics and genomics program, has an emphasis on uncovering the molecular and cellular mechanisms for fertilization.
“It’s an ideal environment for those interested in reproductive physiology to apply critical thinking in solving complex problems relevant to both agricultural and biomedical sciences,” Weide says.
Your Next Read: Gene Editing: Livestock Genetic Improvement Through DNA Editing
