A demonstration study conducted by livestock nutrition company CopRice has shown that a ‘loose blend’ of processed cereals, vegetable protein meals and non-forage fibres can provide a cost-effective alternative to silage during times of limited supply.
CopRice operates a model farm in northern Victoria to examine the effectiveness of integrated nutritional strategies and new formulations under real-world conditions.
Each year, the company implements dozens of projects that aim to optimise animal health, fertility, productivity, environmental sustainability and profitability.
Model farm partners — Fred, Sonyia, Daniel and Ben DeCicco — milk a herd of high production registered Holstein cows at Undera.
The DeCiccos usually provide a partial mixed ration (PMR) to their cows over summer to complement their lucerne pastures and fodder crops.
However, faced with the complexity of an exceptionally dry summer and escalating water costs, the family opted to supply a total mixed ration (TMR) to their herd over summer.
The initial ration comprised farm-grown pasture silage (68 per cent DM) and maize silage (12 per cent) and purchased vetch hay (10 per cent) and cereal hay (10 per cent).
This was supplemented with 6.2 kg/day of CopRice dairy pellets fed in the bails.
As available stocks of maize silage tightened, the CopRice team investigated how to maximise the utilisation of the pasture silage content and reduce the level of purchased feed resources.
The maize silage component and part of the vetch and cereal hay levels in the TMR were replaced with a ‘loose’ blend of processed cereal grains, vegetable protein meals and non-forage fibre sources.
The highly-digestible ration was formulated to deliver 18 per cent protein, 11.8 MJ/kg energy and 30 per cent starch.
Following a rumen adaptation period, the levels of vetch and cereal hay in the TMR were reduced by about 20 per cent and the amount of pellets fed in the dairy was reduced to 4 kg/day, while total feed offered to the herd remained the same (24.7 kg/day).
CopRice model farm manager Ellen Fitzgibbon said the reformulated TMR had a marked impact on boosting milk production efficiency.
“At the start of the trial in late January, the herd comprised about two-thirds spring-calving cows in late lactation and about one-third fresh autumn-calving cows,” she said.
“Milk production averaged 27.5 litres/day, while milk composition averaged 4.2 per cent butterfat and 3.2 per cent protein.
“Within six weeks, milk production had increased to 30 litres/day, while milk composition had increased to 4.59 per cent butterfat and 3.45 per cent protein.
“Total milk solids production increased by 17.6 per cent to 2.4 kg/day, which helped to improve the margin over feed cost by 0.63 cents/cow/day.”
These results were sustained until the completion of the project at eight weeks, when cows were transitioned back to forage pastures and new-season maize silage.
Ms Fitzgibbon attributed the significant production increases to improved rumen health and digestibility.
“The loose blend provided a rich source of high quality, digestible ingredients and reduced the large, twice-daily fluctuations in ruminal pH that can occur with high levels of ‘slug feeding’ inside the shed,” she said.
CopRice now markets a range of commercially-available ‘loose mixes’ under the DairyBlends brand name.
They utilise a range of processed cereal grains, vegetable protein meals and non-forage fibre sources to complement available feed resources or to replace conventional feed ingredients that may be in limited supply.
Depending on seasonal availability, raw ingredients may include processed wheat, barley, maize, lupins, canola, soybean, cottonseed, palm kernel, almond hulls and grape pomace.
Ms Fitzgibbon is an accredited adviser for the Dairy Australia InCalf Program and a committee member of the Australian Association of Ruminant Nutrition.
She graduated from La Trobe University with a Bachelor of Veterinary Bioscience (Hons).
Her research on markers of fertility in colostrum was awarded Ag Institute Australia’s Richardson Memorial Award in 2015 for outstanding contribution to agricultural research.