Plasma lipoprotein concentration as an indicator of fatness in broilers: development and use of a simple assay for plasma very low density lipoproteins.

1. A turbidimetric assay for plasma very low density lipoproteins (VLDL) was developed, based on their selective precipitation with heparin and Mg2+. 2. Measurements of plasma VLDL concentration using the turbidimetric method showed a correlation of 0.98 with plasma VLDL plus low density lipoprotein triglyceride concentration estimated chemically. 3. Correlations between plasma VLDL concentration measured turbidimetrically and body fat content were similar to or higher than those obtained previously using a chemical assay. Correlations for broiler grandparent stock fed on a low-fat diet were 0.70 and 0.65 for males and females respectively. 4. Turbidimetric measurement of plasma VLDL concentration provides a simple, rapid and effective method of estimating fatness in live broilers that could be applied to commercial broiler breeding programmes.