Researchers have known that chronic stress has many negative health effects that can impair normal growth. The impact of stress on skeletal muscle specifically is less understood. For this reason, researchers at Universidad Andres Bello in Chile explored the effects of stress induced by overcrowding in fine flounders (Paralichthys adspersus). Their results were published this month in American Journal of Physiology – Regulatory, Integrative and Comparative Physiology.
After just four weeks of living in an overcrowded environment, these fish had increased levels of circulating stress hormones. After 7 weeks, levels of hormones important in regulating growth were reduced resulting in overall reduced muscle growth.
Twenty years ago, flounders were one of the top ten consumed fish in the United States. That is, until their populations began to decline. Most people now consume flounder raised in fish farms. In fact, aquaculture is a big-business. In 2013 alone, $1.4 billion in aquaculture products were sold in the United States alone. Fish accounted for over half of the aquaculture products sold. As overcrowding can result in muscle (i.e. meat) loss, this research should be of interest to aquaculture farmers.
CA Valenzuela,R Zuloaga, L Mercado, IE Einarsdottir,BT Bjornsson, JA Valdes, A Molina. Chronic stress inhibits growth and induces proteolytic mechanisms through two different nonoverlapping pathways in the skeletal muscle of a teleost fish. American Journal of Physiology – Regulatory, Integrative and Comparative Physiology. https://doi.org/10.1152/ajpregu.00009.2017
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