Animal weight (A), length (B), mortality rate (C) and organ weight (D) taken daily in animals exposed to 670nm compared to controls in normal atmospheric oxygen.

<p>(A) From P12 there was a statistically significant (* indicated p<0.05) deviation from normal weight gain with animals gaining weight at an increased rate. (B) There were no noticeable differences in the length of the animals over the 21 day period. (C) There was no change in the weight of the organs investigated except for the lungs which showed a significant increase in weight (* indicates p < 0.05). (D) 670nm red light appears to reduce the mortality rate from 27% in controls (n=27) to 15% in the 670nm (n=21) exposed animals (* indicates p<0.05). All animals were raised in normal atmospheric oxygen. Littermates were used to reduce variability across litters. Graph bar fills indicate controls (grey bars), 670nm treated (white bars).