Interpretive Summary: Impact of increasing levels of fumonisin on the health and performance of beef steers
By: Anne Kamiya, MS
Contamination of corn-based feeds with the fungal mycotoxin fumonisin poses a serious risk to the health and safety of many animals. Fumonisin is carcinogenic and also causes an array of severe pathologies, including diseases of the brain, liver and lungs. The FDA has therefore set guidelines on the maximum allowable levels of fumonisin in corn-based feed. However, these guidelines are based on studies that lack data in ruminants.
The authors of this recent Journal of Animal Science study evaluated the effects of fumonisin on cattle at concentrations below and above the current FDA maximum allowed levels. Their goal was to determine at what point feed intake and performance were hindered by fumonisin.
Beef steers were fed a corn-based diet containing either no added fumonisin (the control diet), or up to 90 ppm from day 50 to day 160 when cattle were slaughtered. The current FDA regulations for cattle feed sets the maximum fumonisin concentration at 60 ppm of dry matter. Performance indicators and biopsies from skeletal muscle, kidney and liver tissue were collected in this study at regular intervals. Body weight, carcass characteristics, tissue biopsies and dry matter intake were similar in all groups regardless of the fumonisin concentration in feed. However, with more fumonisin, liver amino alcohol concentration, ADG, and sphinganine and sphinganine/sphingosine (SA:SO) liver ratio all increased.
The results of this study showed no negative effects on carcass characteristics or performance indicators in cattle fed up to 90 ppm of fumonisin for 110 days. These results suggests that cattle may possibly be more tolerant to fumonisin toxicity than previously suggested by the FDA. Larger, more comprehensive studies looking into the maximum safe allowable concentration of fumonisin in corn-based cattle feed is well justified.
The full paper can be found on the Journal of Animal Science website.