A study of soya substitutes proves insightful
A recent study with the aim of identifying sustainable protein sources other than soya has produced interesting results.
Soya is an important component of sheep feeds because it provides high quality protein. All soya, however, is imported into the UK.
The purpose of the research undertaken by ADAS and supported by Hybu Cig Cymru – Meat Promotion Wales (HCC) was to evaluate other protein sources that can be grown in this country to improve the long term sustainability of UK sheep production.
It was based on a sample of approximately 240 ewes aged 1-7 years, scanned as carrying twin lambs and due to lamb in February and March 2014. They were randomly allocated to six treatment groups of 39-40 ewes at housing in January 2014. Ewe live weight and body condition was assessed from housing in January until weaning in July.
“Six groups of ewes were fed good quality grass silage along with different protein and energy sources, namely fodder beet or cereals,” said Lynfa Davies, HCC’s Technical Development Executive. “The project then looked at how the ewes and lambs performed on the different diets.
“The research demonstrated that rapeseed meal, wheat distillers grains and beans can all be used as substitutes for soya bean meal in the diets of twin bearing and rearing ewes that have been fed silage of a good quality.
“Poorer silage, however, would mean a higher level of supplementary feeding. This highlights the importance of producing high quality silage as it can have detrimental effects on the profitability of a farm.”
The six treatments were: control – soya bean meal with cereals; rapeseed meal with cereals; wheat distillers dark grains (WDDG) with cereals; field beans with cereals; rapeseed meal with fodder beat; and WDDG with fodder beat.
Feed costs were found to be higher for the Barley/soya group with the cheapest being the Barley/WDDG diet. Supplementary feeding costs for ewes fed poorer quality silage, however, are estimated to be nearly double those calculated in the study.
Ewe live weight and body condition score were unaffected by the protein source, and lamb weights at birth, four weeks and eight weeks did not differ between treatments. Performance of twin lambs that received creep feed was consistently above 300g/day on all treatments between birth and eight weeks.
The research report, entitled ‘Sustainable protein sources for pregnant ewes,’ was published in December 2014 and can be found on HCC’s website: http://hccmpw.org.uk/farming/research_and_development/sheep-management/sustainable_protein_sources/Back to news listing