Grass isn’t always greener

Sheep also get busy chasing the “green pick”, but producers need to be extra vigilant with nutrition in the aftermath of a downpour.

Geoff Duddy, sheep expert and owner and manager of Sheep Solutions at Yanco, said excessive heat and wet could put the animals off their feed.

“Then they tend to gorge themselves,” Mr Duddy said.

With the balance of bacteria disturbed in their gut, Mr Duddy said sheep were then at risk of grain poisoning when they returned to supplementary or drought feeding rations.

“That 24 to 36 hours they stop eating the grain disturbs their intake pattern,” Mr Duddy said.

“The most important thing to do is to cut back the level of feed after stinking hot weather, or if they are going off the feed because they want to chase a green pick, or if they are affected by the rain.

“Cut back and build it up slowly.

“For example if you’re feeding a kilogram of grain to a ewe after a day or two of wet weather, drop back the amount you’re feeding per head and this gives the bugs in the gut the time to re-adjust to the grain.”

The “green pick” (the early shoots on pasture after rain), whether it’s grass or crops is between 70 and 80 per cent moisture.

“For every kilogram they eat, they’re only getting about 200 grams of fibre,” Mr Duddy said.

“They are filling up on moisture and feeling full.

“They will preferentially graze green and go off the grain, but they’re physically not getting enough bulk or roughage into their diets.”

While green pick would provide the sheep with most vitamins and minerals, they run a risk of missing out on calcium and magnesium.

For pregnant ewes, like those in the Murrumbidgee region that are autumn lambing flocks due in March, April and May, the lack of calcium can be a major issue.

“If they don’t get enough calcium they can get hypocalcemia (milk fever),” Mr Duddy said.

“So calcium is the main mineral that can be supplemented.”

Magnesium levels should also be considered.

“Whether it’s the green pick from grass or cereal crops, it’s deficient in magnesium, so you should look at supplementing that,” he said.

“As a rough rule of thumb mixture, I recommend two parts lime, two parts salt and one part CausMag magnesium supplement with the stock at the moment.”

Mr Duddy said the main concern coming out of a dry feed period was the ewes’ energy requirement.

“There is a high risk if there is wet weather at the point of lambing if sheep go off feed, they have a high energy requirement to supplement grain feeding to keep those energy levels up.

“A twin-bearing ewe at the point of lambing needs two-and-a-half times the energy feed requirement of a dry sheep or wether.

“Anything that will interrupt her feeding with grain or cause her stress can lead to pregnancy toxaemia.”

Mr Duddy said another big issue following the recent rain would be the deterioration of the available dry feed.

“The feed that was out there, but perhaps wasn’t enough to keep them in the stage of production they’re in will now be even worse.”

He said there hadn’t been enough rain to fill dams and because it was so dry, the wet just infiltrated the ground.

However, he said producers in the south of the State were fortunate to have, after the rice harvest finishes, stubble that will fill a feed gap.

“In recent years the benefits of grazing cereals have really come into their own,” Mr Duddy said.

“Scratch in a bit of oats in six or eight weeks’ time – they can graze those – and farmers should be mindful of green pick.”