Sprouted sorghum: feed quality not dampened
Author: Rachel Bowman | Date: 15 Mar 2013
With recent rains has come sorghum sprouting across southern Queensland and northern NSW but research challenges conventional thinking that this grain has inferior feed quality and should be discounted.
James Clark, Grains Research and Development Corporation (GRDC) northern panel chair says research carried out under the Premium Grains for Livestock Program (PGLP) shows sprouting has little or no effect on feed value, provided it is not contaminated with fungal growth.
“Trials showed the energy content of sprouted grains for animals was not decreased and in some circumstances may be increased when compared with non-sprouted grain,” Mr Clark said.
“The effects of germination were particularly favourable for a barley sample fed to broiler chickens and sorghum fed to cattle.
“This is an issue that the grain market needs to take a closer look at so that growers are receiving fair payment for the grain they produce.”
GRDC co-funded the project which was carried out by the several research organisations across Australia and co-ordinated by researcher Dr John Black, John L Black Consulting, Warrimoo, NSW.
Dr Black said there was no detrimental effect of sprouting on the energy value of grains for animals, however the effects of storage on the possible deterioration of sprouted grain or of mycotoxins that may develop needed to be examined.
“The research analysed sprouted sorghum samples collected from the Moree, NSW district which had been significantly downgraded at the grain depot,” Dr Black said.
“The starch content and in vitro fermentation and digestion were compared with the mean values from all other sorghum samples and results suggested the starch content and nutritional value of sorghum were unaffected by sprouting.
“As part of the trials grain was fed to sheep, pigs, broiler chickens and layers and a comparison of available energy content and total available energy intake suggested the sprouted sorghum was not substantially different from the other sorghum samples examined.”
Two cultivars each of wheat and barley and three cultivars of sorghum were also germinated for periods from 16 to 48 hours and germination ceased by drying.
“Germination for these periods did not alter the starch content of the grains, but reduced significantly the Falling Numbers values that measure the degree of starch breakdown by the grain enzyme amylase,” Dr Black said.
“Germination did not affect the microbial fermentation of starch. However, the rate of starch digestion appeared to be increased with a significant increase in total acid and lactic acid production with all grain species.
“These results indicate that germination increases the accessibility of both rumen microbial and animal digestive enzymes to starch and increases the rate of starch digestion for all cereal species examined.”
PGLP was funded by GRDC, Meat and Livestock Australia (MLA), Australian Pork Limited (APL), Rural Industries R&D Corporation (RIRDC), Australian Egg Corporation Limited (AEC), Ridley AgriProducts and Dairy Australia (DA).
Dr Black said the project aimed to identify the characteristics of grains that made them most suitable for different forms of animal production; and develop a process, based on the rapid measurement of grain quality, for the rational trading of grains for livestock within Australia which provides just rewards to both the grain growers and livestock producers.
The project stemmed from rapidly increasing demand for grain from the livestock and dairy industries and the need to ensure supply at an appropriate price point.
The near Infra-red (NIR) calibrations for predicting the energy value of cereal grains for different livestock species developed in the program are now available to the grains and animal industries through the Pork CRC, AusScan project.
Caption: The feed value of sprouted and unsprouted sorghum grain may not be too far apart, according to research.
GRDC CODE: JLB2
For interviews contact:James Clark, GRDC Northern Panel Chair
0427 545 212
Dr John Black, Research Management Consultant
John L Black Consulting
Ph: 02 4753 6231
Mobile: 0419 493 567
Rachel Bowman, Cox Inall Communications
07 3846 4380 / 0412 290 673
GRDC Project Code JLB2
Region National, North