It Ain't Chickenfeed¹
by Bob Hartzler
February 20, 2002 -  At a recent meeting where we were working on revamping Iowa's Noxious Weed Law  (something that is long overdue), our discussion digressed to poisonous weeds.  Mike White, Area Field Crop Specialist in south central Iowa, mentioned that velvetleaf seed could cause problems if fed to laying hens.  He stated that research had shown chickens fed velvetleaf seed would produce eggs with rubbery yolks.  Being somewhat skeptical, I questioned Mike on the validity of this fun fact.  Well, Mike was able to produce an article from the January 1993 issue of Ag Consultant (he obviously has a much better filing system than I) that proves he knew what he was talking about.

Researchers at Cornell University isolated two fatty acids in velvetleaf seed that deactivate a liver enzyme responsible for converting saturated fats into unsaturated fats.  Chickens given feed containing 1.5% velvetleaf seed produced egg yolks with 55% saturated fats compared to only 33% saturated fat in eggs from chickens not given velvetleaf seed.  The increased saturated fat content resulted in yolks that turned rubbery within 24 hours of refrigeration.  Uncooked yolks from these eggs would not break open when poked with a fork.

It just shows that you can learn something new everyday, and Mike White has earned my highest level of respect for retention of weed trivia.

¹Please forgive the bad grammer - this title just seemed to have a nice ring to it.

 Prepared by Bob Hartzler, extension weed management specialist, Department of Agronomy, Iowa State University