The effect of cysteine and B group vitamins on the skin of the white laboratory mouse infested with the mite Myocoptes musculinus (Koch)

Abstract

1. Mice were given a supplement of nicotinic acid, riboflavin or B complex from 1 to 6 months.2. One mouse of each group was then infested with Myocoptes musculinus for a period of 1 week or 8 weeks. At infestation the supplement was discontinued. Alternatively infestation lasted 8 weeks, the supplement being continued until death.3. The mitotic rate was estimated for the epidermis of clean and infested mice and the rates compared.4. Other mice were fed cysteine for periods of three months, one was then infested for a period of 8 weeks before being killed and the mitotic rates of the clean and infested mice compared.5. It was found that after supplementing the feed of the mice by members of the B group vitamins, quite large numbers of mites (M. myocoptes) could be carried without deleterious effect to the host and without signs of mange.6. With cysteine supplementation, no gross signs of mange were seen but the mite affected the skin by raising the mitotic rate in the malpighian layer.I wish to thank Vitamins Limited for supplying the vitamin supplements; and the Royal Free Hospital School of Medicine for facilities for carrying out the work; also Dr A. M. Hughes for her helpful guidance at all stages of the work and especially for reading the paper.