Re-alimentation of phosphorus deficient cattle

The Re-alimentation of phosphorus deficient cattle project investigated the responses of phosphorus deficient animals to a high phosphorus supplement.

Feed intake and liveweight gain are affected by phosphorus (P) content of the diet. For example, in the MLA project, Validation and demonstration of a diagnostic tool for phosphorus status of beef cattle (B.NBP.0537) cattle fed a P deficient diet had reduced feed intake and liveweight gain over a 20 week period.  However, it was unknown how quickly P deficient animals respond when offered a P supplement and the magnitude of the response.

The Re-alimentation of phosphorus deficient cattle project examined the response of animals of various P status to a high P supplement. It used animals generated in B.NBP.0537 and fed them a diet representative of early wet season pasture (~10 to 11% crude protein and 60 to 65% digestibility) supplemented with biofos to provide ~0.25% P/kg DM.  Feed intake, liveweight gain, hip height, bone density, plasma inorganic P, faecal P and carcass data were collected.

This project aimed to:

  • determine the response (in terms of feed intake, liveweight gain, faecal and plasma P, hip height and bone density) of P deficient cattle to a high P diet (both the speed at which the response occurs and the magnitude of the response)
  • determine if relationships between faecal P:dietary DMD exist in animals that are P deficient and are fed a high P diet
  • examine allometric growth in P deficient animals undergoing compensatory gain.

For more details, please read the final report summary and download the final report (B.NBP.0565) (PDF, 542.3KB) from Meat & Livestock Australia.

When: 1 September 2011 to 1 July 2012

Contact: Dr Simon Quigley

Collaborator: University of Queensland