How implants work
What are hormones?
Hormones are natural chemicals found in all mammals, including humans, that help to regulate certain physiological processes such as growth, metabolism and reproduction.
Extensive research has shown that the provision of oestrogens (or compounds with oestrogenic activity) and/or androgens (or compounds with androgenic activity) can significantly improve the growth rate and feed conversion efficiency of cattle when administered at relatively low levels.
Implants are registered for use in more than 30 countries throughout the world.
How do hormones work?
Hormones are anabolic compounds that promote constructive metabolism (i.e. protein deposition).2
Oestrogenic compounds stimulate the pituitary gland to release more of the body’s own natural growth hormones, increasing satellite cell proliferation, amino acid uptake and protein deposition.2
Androgenic compounds act directly on muscle tissue, stimulating protein/muscle synthesis and reducing muscle breakdown.2
How do implants differ?
There are a number of implants registered for use in beef cattle in Australia. These formulations typically contain an oestrogenic compound, sometimes in combination with an androgenic compound.
The active ingredient(s), formulation and length of payout of the selected implant have a direct impact on the performance and recommended usage of each implant.
All implants deliver a level of hormone above a threshold to promote growth for a particular payout period. Once the payout period ceases, the available hormone drops below the threshold and growth promotion stops.
1. Assessment of benefits from using HGPs, Fresh Agenda (2014) 2. Reinhardt, C. (2007). Growth-Promotant Implants: Managing the tools. Vet Clin Food Anim 23: 309–319.