Comparative Analysis of Citrate Synthase Activity in Skeletal Muscle, Liver, and Adipose Tissue in Beef Cattle

Authors

• Abigail Webb, University of Nebraska - LincolnFollow

First Advisor

Jessica Petersen

Second Advisor

Kristi Montooth

Date of this Version

Fall 10-26-2025

Document Type

Thesis

Citation

Webb, A. 2025. Comparative Analysis of Citrate Synthase Activity in Skeletal Muscle, Liver, and Adipose Tissue in Beef Cattle. Undergraduate Honors Thesis. University of Nebraska–Lincoln.

Comments

Copyright Abigail Webb 2025

Abstract

Mitochondrial efficiency plays a central role in determining how cattle partition nutrients toward muscle growth or adipose deposition, yet little is known about tissue-specific differences in mitochondrial density among tissues or among beef cattle. This study aimed to quantify mitochondrial density in muscle, liver, and adipose tissue samples from beef cattle and evaluate its potential relationship with metabolic efficiency. Tissue samples of semitendinosus muscle (ST), liver, and subcutaneous adipose (SC) were collected, homogenized, and analyzed for citrate synthase (CS) activity using a fluorometric assay as a proxy for mitochondrial density. Preliminary analyses revealed that the semitendinosus muscle displayed the highest CS activity, adipose tissue showed moderate activity, and liver tissue exhibited the lowest levels. Statistical testing showed that CS activity in the ST muscle was significantly greater than that of both SC adipose (P = 0.0016) and liver (P = 0.0001). Additionally, CS activity in SC adipose tissue was significantly greater than in the liver (P = 0.0001). These results suggest that mitochondrial distribution varies significantly across tissues, reflecting their unique metabolic roles. Together, these findings help to explain how variation in mitochondrial density may influence feed efficiency, muscle growth, and adipose storage in livestock production.