Tips for Managing Grazing Cereal Crops this Winter
It is that time of the year where grazing cereal crops can play an important role in many livestock enterprises. Grazing winter cereals helps with feed shortage in the cooler months and helps to spread income risk through utilizing high quality feeds and has been shown to reduce weed biomass at harvest (Dr Hugh Dove, CSIRO Research, GRDC GroundCover issue 109, March 2014).
Monitoring crop growth is important to ensure that the crop is not grazed too early (before the plant is well anchored) and that it is not grazed past GS30/GS31 as this will cause impacts with grain yield. By implementing a small ‘exclusion cage’ in the crop (stop animals grazing the crop in the cage), will allow the crop to be monitored accurately and stock to be removed at the appropriate time to avoid any grain penalties.
Stocking rates will vary depending on the animals production requirements but the ‘rule of thumb’ according to CSIRO research suggests grazing at about 1000kg of stock liveweight per hectare (33 sheep and 30kg each or 3 cattle at 330kg each) is most beneficial to get the most out of your cereal.
It is also important that livestock performance is not reduced by mineral deficiency or imbalance and that ewes lambing do not reach an excessive body condition score at late trimester as this will cause lambing problems. Cereal crops are very high in potassium and low in magnesium, salt and calcium. It is important that mineral supplements are on offer as this is the perfect diet to induce Grass Tetany, Ketosis, Milk Fever or Twin Lamb disease when grazing at lambing or pre-lambing. High levels of potassium in the diet limit the absorption of magnesium in the gut and this is another reason why mineral supplements need to be on offer to ensure that livestock weight gains continue throughout the grazing period. It is also important that all livestock about to graze a cereal crop are up to date with vaccinations as pulpy kidney is likely to occur in this situation.
The following table produced by GRDC demonstrates the importance of providing mineral supplements when grazing cereals to increase liveweight gains.
Source: Cattle data courtesy of Rebecca van Es, University of Western Sydney, and Julian Minehan, Landmark, Goulburn.
Figure 1. Impact of mineral supplementation on the liveweight gains of sheep and cattle grazing dual-purpose wheat in south-east NSW and the ACT.
By contacting your local Western AG Animal Health Specialist, we can advise you on the correct mineral supplements for your livestock. We can also help to create an effective vaccination program to avoid metabolic issues when grazing, ensuring you can get the best return for your livestock.
Article produced by - Emily Clothier, Western Ag Horsham