- news, features, articles and disease information for the beef industry


Zilmax Safe If Stricter Protocols Followed

14 November 2014

US – Cattle feed additive Zilmax is safe but a raft of labelling and management revisions are required to ensure ‘appropriate’ use.

Feeders are now advised to dose no more than 90 milligrams of Zilmax per head each day as part of new guidelines arising from extensive analysis of the product’s safety.

A new administration method - “component feeding” - will provide cattle with a controlled delivery system, supplying 60 milligrams to each animal daily.

Food and Drug Administration approved dosage guidelines are informed by insights into industry data showing a steady increase over time in cattle weights and feed consumption rates.

According to product manufacturer Merck, overseeing the safety assessment, this has created “the possibility that certain cattle could consume feed quantities that result in ingestion of Zilmax in an amount that exceeds the approved dose.”

Accompanying ‘enhanced label language’ is a training and certification scheme to help producers achieve new best management practices.

Measures range from animal handling and transportation to nutrition protocols, environmental factors and cattle selection.

New labelling communicates that Zilmax should note be fed if pen consumption of complete feed exceeds 26.5 pounds per head per day, at 90 per cent dry matter basis. 

Merck’s announcement is the latest update in its ‘Five-step plan’ for Zilmax, chemical name zilpaterol hydrochloride.

The company has described “significant progress” made, with a final stage to include ‘in-field’ studies.

These studies will;

  • Observe cattle throughout the system – before and after receiving Zilmax – at the feedyard and at the packing plant
  • Evaluate the mobility of cattle by trained third-party experts utilizing an established mobility scoring system
  • Review potential confounding factors, such as nutrition, transportation, receiving facilities, flooring surfaces and, cattle management and handling practices, given that mobility issues can be the result of numerous issues or even multifactorial in nature

Merck’s senior vice president for global research and development, Dr KJ Varma said that Merck’s commitment to the highest standards of cattle health and well-being was unwavering.

He added: “We are pleased to announce the addition of Component Feeding to the Zilmax label, and are equally excited to note we are moving ahead with the Five-Step Plan.”

Michael Priestley

Michael Priestley
News Team - Editor

Mainly production and market stories on ruminants sector. Works closely with sustainability consultants at FAI Farms


Top image via Shutterstock

Our Sponsors


Seasonal Picks

Animal Welfare in EPS - 5m Books