The vitamin E concentration in pig muscle biopsy specimens. A methodological study.

Two litters of weaned pigs were housed in the same stable and fed a commercially available diet for five months. When the pigs weighed about 90 kg, surgical biopsy specimens (about 3 g), were obtained from the superficial portion of the biceps femoris muscle. In addition, samples weighing about 100 mg were taken from the deep portion of this muscle by the needle biopsy technique. The surgically obtained biopsies were divided into two pieces, one for determination of the vitamin E concentration in whole wet muscle and the other for determination in pure muscle and debris (blood, connective tissue and fat). The latter piece was freeze-dried and the pure muscle was separated from the debris by dissection. The vitamin E concentration in whole wet muscle correlated (p less than 0.05) with that in pure muscle tissue. However, in individual biopsy specimens the vitamin E values in pure muscle were sometimes similar to those in debris and sometimes very different. The range of values in pure muscle was much narrower (7.1 to 12.0 mg/kg), than in debris, where it was 7.1 to 41.8 mg/kg dry weight (dw). These data show that the vitamin E concentration can be measured in very small muscle samples obtained by the needle biopsy technique, provided that the analysis is performed on pure muscle freed from blood, connective tissue and fat. It is clear that pure muscle is preferable to whole wet muscle for this analysis irrespective of the size of the sample.