Tuesday, February 9, 2016

Sex-change fish and factory chickens: Update

UMD researchers say sex hormones from chicken plants appear to be turning male fish into females

Sex-change fish and factory chickens: Update


Lakes in the chicken-raising country south of Philadelphia are producing mutant largemouth bass, with male sex organs - and female eggs. Lots more "intersex" fish have also turned up in the Susquehanna, Chesapeake and Potomac.

"We find it in every lake that we look," Daniel J. Fisher, senior research scientist at the University of Maryland's Wye Research and Education Center in Queenstown, MD, told the Baltimore Sun here. "Intersex" fish at lakes in central Delaware and Maryland's Eastern Shore range "from 33 percent of fish we sampled to 100 percent."

"In separate laboratory tests, the UM researchers said, they found the sex and development of certain juvenile fish were affected when exposed to water contaminated with poultry waste," says the Sun.

"Fathead minnows displayed changes in their gonads, or sex organs, and larval minnows experienced "pronounced feminization." By contrast, mossbunkers put through similar tests didn't change sex, but they still showed a reaction to elevated female hormones, if I'm reading the summary of their original report correctly.

Fisher, Lance T. Yonkos, and their colleagues reported their findings in October's Environmental Toxicology and Chemistry journal.  More from the US Fish and Wildlife Service here.

UPDATE: Don't blame hormones or runoff from the Peninsula's millions of avian residents for the she-male fish, says industry lobby Delmarva Poultry Council 's Bill Satterfield: It's still "speculation at best, and unproven" to associate the "feminization" of male fish to runoff from hormone-treated poultry farms.

"At best, this report is a weak link between fish estrogenicity findings and poultry-associated litter contaminants," Satterfield says. The cause of the egg-bearing male fish "could have been crop chemicals, common household products... or other pollutants, and not poultry manure; we simply don't know... Keeping little fish in tanks in continuous, long-term exposure" to poultry runoff "is not representative of what happens in nature."

We encourage respectful comments but reserve the right to delete anything that doesn't contribute to an engaging dialogue.
Help us moderate this thread by flagging comments that violate our guidelines.

Comment policy:

Philly.com comments are intended to be civil, friendly conversations. Please treat other participants with respect and in a way that you would want to be treated. You are responsible for what you say. And please, stay on topic. If you see an objectionable post, please report it to us using the "Report Abuse" option.

Please note that comments are monitored by Philly.com staff. We reserve the right at all times to remove any information or materials that are unlawful, threatening, abusive, libelous, defamatory, obscene, vulgar, pornographic, profane, indecent or otherwise objectionable. Personal attacks, especially on other participants, are not permitted. We reserve the right to permanently block any user who violates these terms and conditions.

Additionally comments that are long, have multiple paragraph breaks, include code, or include hyperlinks may not be posted.

Read 0 comments
comments powered by Disqus
About this blog

PhillyDeals posts interviews, drafts and updates that Joseph N. DiStefano writes alongside his Sunday and Monday columns and ongoing articles about Philadelphia-area business.

DiStefano studied economics, history and a little engineering at Penn. He taught writing and research at St. Joe’s. He has written for the Inquirer since 1989, except when he left a few times to work at Bloomberg and elsewhere. He wrote the book Comcasted, and raised six kids with his wife, who is a saint.

Reach Joseph N. at JoeD@phillynews.com, 215.854.5194, @PhillyJoeD. Read his blog posts at http://www.philly.com/PhillyDeals and his Inquirer columns at http://www.philly.com/philly/columnists/joseph-distefano/. Bloomberg posts his items at NH BLG_PHILLYDEAL.

Reach Joseph N. at JoeD@phillynews.com or 215 854 5194.

Joseph N. DiStefano
Also on Philly.com:
letter icon Newsletter