Using organoids to unravel feed efficiency in pigs

First results show differences in gene expression

Improving feed efficiency is an important trait in many livestock species. However, the biological mechanisms underlying feed efficiency are largely unknown. Organoids provide an excellent in vitro model system to study complex traits which are not easily accessible in vivo. HMI, ABG and B4F collaborated in setting up a proof of principle experiment using organoids isolated from intestine samples of slaughtering pigs with divergent phenotypes for feed efficiency to measure nutrient uptake. In total, 12 pigs were selected: 6 efficient pigs and 6 less efficient pigs. From these pigs, tissue from the ileum has been collected and grown to organoids. From both groups, 3 organoid cultures were challenged using commensal E. coli, whereas 3 organoid cultures were unchallenged. A transport study was performed to measure differences in histology and gene expression. Some first results indicate that there are some differences in gene expression between pigs. However, further research is needed to do some more in-depth analysis.

Organoid model valuable for study purposes

Developing the organoid system is very important to study many traits of importance. A literature review showed that the organoid model system has been applied for most of the livestock species, using different organ tissues. Although the organoid model system seems promising to study complex traits, there are still a number of challenges, e.g. developing a robust culture of organoids, validation of the use of organoids as proxy for in vivo performance, high-throughput phenotyping. The proof of principle performed by HMI, ABG and B4F is one of the first validating organoids as proxy for in vivo performance. On the long term, the results of this study can potentially be used to select for better feed efficiency by including biological information as weighted markers in future genomic selection analysis.