Allow me to summarize
Quote:
Originally Posted by Article  Carotenoid pigments are responsible for many examples of sexually attractive red, orange, and yellow coloration in animals and play an important role in antioxidant and immune defenses. Because vertebrates cannot synthesize carotenoids, |
If the fish cannot synthesize, that is to say create carotenoid from other compounds, you must provide the fish with this pigment somehow.
Quote:
Originally Posted by Article A second key assumption of the trade-off hypothesis is that carotenoid supplementation boosts immune activity. Also consistent with this, we found that carotenoid supplementation significantly increased the immune response of male B. splendens, as measured by the swelling of the caudal peduncle in response to PHA injection (Figure 3; mean postinjection swelling in mm ± SE: control = 0.087 ± 0.01 mm, N = 28; supplemented = 0.17 ± 0.02 mm, N = 33; carotenoid supplementation group: F1,58 = 12.68, P = 0.001). We obtained similar results when we used the ratio of preinjection swelling to postinjection swelling as our dependent variable |
So to skip all of the details about everything, after doing an experiment by feeding half of the fish food laced with carotenoids and compairing them with the other half, they found that the group that had received the carotenoids had stronger immune response and brighter colors.
So we need to feed our fish tiny pieces of carrots to give them brighter colors and stronger immune systems.
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I've never even heard of it! haha
