Sheep health and nutrition tips in a heatwave

So far, the hot, dry summer, especially after a tough spring, is making it difficult for sheep producers to get lambs fit and off farm while keeping ewes in good condition.

Grass growth is stagnant across much of the UK meaning grazing pressure is high at a time when most farmers are trying to wean and finish lambs before getting ewes ready for the tupping season.

Sheep nutrition and health experts were on hand at the Three Counties Showground, Malvern, Worcestershire to advise visitors to the National Sheep Association’s Sheep Event on Wednesday (18 July).

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Prioritise

Sheep vet Fiona Lovatt of Flock Health said producers need to prioritise to manage this difficult stage.

“More than anything, they need to be body condition scoring (BCS) and dividing their flock so they’re not at the mercy of the weather,” she said.

“Lambs are the priority now, get food into them and get them away,” she advised. “But people cannot afford to sacrifice ewes.”

Mrs Lovatt said farmers should group the flock into thin, fit and fat – although there probably aren’t many fat ewes around at the moment – so they can manage them accordingly.

Producers should aim to get ewes at a BCS of 3.5 by 10 days before tupping and it takes six weeks to gain one condition score point, so attention is needed now to get and keep them fit.

Supplementation

Nick Canning from Strathclyde Nutrition said farmers should consider getting lambs off ewes as soon as possible to reduce pressure on the grass and ewes and consider supplementation.

He said, with grass growth poor on many farms, hay volumes due to be down and silage stocks due to be about 30% less than normal, many farmers will be grazing cattle for longer into the winter and therefore, grass availability for sheep will be further reduced.

By reducing pressure on ewes, which require 10MJ of energy a day for maintenance, Mr Canning says you can increase the amount of grass available for silaging and haymaking to contribute to winter feedstocks.

“If you take a ewe with twin lambs – if you can get the lambs off the ewe and you can supplement her, you can get four ewes in her place,” he said.

“If you can get four ewes onto the same pasture for one [ewe], you can get fields shut up for silage and hay and that’ll survive you the winter.”

Mr Canning explained to delegates that, assuming grass is 18% dry matter with 10.5MJ/kg DM energy content, you can reduce the grass requirement of a ewe carrying twins from 13.07kg to 5.29kg if you wean the lambs.

This would give enough grass for 2.5 ewes in the place of one twin-carrying ewe. In addition, supplementation with an energy block can further reduce the necessary grass intake  to 3.57kg, meaning the same amount of pasture for one twin-bearing ewe can feed four ewes (see “Feeding requirements”, below for more detail).

Feeding requirements

 

Energy requirement (MJ)

Kg fresh grass* required to meet energy requirement

Kg of fresh grass* required if supplemented with 250g of a 13ME feed block

70kg ewe

10

5.29

3.57

70kg ewe producing 1 litre milk/day

16.5

8.73

7.01

70kg ewe producing 2 litres milk/day

24.7

13.07

11.35

Assuming grass is 18% dry matter with 10.5MJ/kg DM energy content