In Vivo Body Composition Analysis Technology (Fat Content) in Animals

Body composition in live animals:

Body composition refers to the major components of an animal’s body, typically including:
Muscle: the controller of the body, providing the basis for movement.
Skeleton: the framework, offering support and protection.
Fat: the storage unit, serving as the primary energy reserve.
Body fluids: mainly free-flowing fluids within the body, such as urine.

The value of body composition analysis:

Fat is one of the most important components in body composition. Measuring fat content in animal tissue samples provides crucial information for research in nutrition, obesity, diabetes, oncology, and beyond. For example, it helps assess the quality of food-animal products and determine the nutritional value of animal-derived feed.

Techniques for body composition analysis (fat measurement)
There are several methods for measuring fat content in animals, including chemical analysis, X-ray techniques, and low-field NMR body composition analysis.

Chemical analysis:

This method uses solvents and reagents to extract and quantify fat from animal tissue. The most common approach is Soxhlet extraction, which continuously extracts fat over several hours. However, animals must be sacrificed prior to testing, making it unsuitable for in vivo fat measurement.

X-ray absorptiometry:

This technique measures variable absorption of high- and low-energy X-rays by different body tissues. Calcium and phosphorus atoms in bone have higher atomic numbers than carbon, nitrogen, and oxygen in soft tissue, enabling distinction between bone and soft tissue. Fat and muscle also attenuate X-rays differently, allowing fat measurement. Advantages include in vivo testing, but drawbacks include radiation exposure, anaesthesia requirements, and relatively long scan times.

Low-field NMR body composition analysis:

Low-field NMR exploits differences in relaxation times of fat, lean tissue, and water in vivo. The detected NMR signals can distinguish between fat, lean tissue, and water, enabling quantitative measurement of each. This yields fat, muscle, and water content simultaneously. The test takes just 1–3 minutes, is rapid and non-destructive, and can be performed on awake animals. Advantages include speed, precision, stability, and safety.

QMR06 Small-Animal Body Composition Analyser

No matter which method is used, it is essential to ensure that the test sample is representative of the animal and that results are accurate and reliable. This is achieved through appropriate sample preparation and strict adherence to validated testing protocols.