By Kirsten Williams, senior beef and sheep consultant at SAC Consulting

Continuous dry, warm/hot weather is having a negative effect on animal performance and feed stocks across Scotland which comes as no surprise when temperatures of over 30 degrees centigrade have been recorded.

Thermal comfort zone is when animals do not have to use extra energy to regulate heat and for cattle this zone is between 13 and 25 degrees C and for shorn sheep this is between 7 and 29 degrees C.

The rumen is one of the major sources of heat and in hot weather results in reducing intakes of up to 10-30% of dry matter intake. This in turn will decrease the daily live weight gain and performance of an animal. For grass the optimum temperature for growth is 25 degrees C but moisture is essential, the lack of moisture is the reason for fields burning up and yields being vastly reduced.

There are numerous management techniques that should be considered for late summer. Initially, grazing stock must be given priority, for example autumn-calving cows, nutrition is paramount to ensure the calves get the adequate colostrum and milk supply that is required as well as allowing the cow to regain condition before returning to the bull.

For sheep, many had a hard winter and have now reared lambs, the condition of the ewes must now be managed to ensure they are in target condition for tupping to maximise conception rates. By prioritising the breeding stock you are protecting next year’s crop of calves and/or lambs.

Identify the stock which is not a priority and look to market these to reduce the pressure on the grass supply e.g. cull cows and ewes.

Other management options include making arable silage from cereal headlands at the cheesy ripe stage, baling EFA field margins (after July 15) or AECS field margins (after August 15), harvest cereals 2-3 weeks earlier (hard dough stage) as cracked whole crop, leaving higher stubbles when cutting silage to allow the grass to regrow quicker and the possibility of making arable silage or whole crop from light arable spring crops.

Reducing the amount of livestock on the holding is another option. Look to stock that is not a priority such as cull and barren cows and cull ewes, which could be marketed.

It is also worth considering early lamb weaning as they will thrive better without competition for grass from their mothers, as long as there is good quality grass to wean them on to. At six weeks of age, a lamb will be gaining a third of its energy intake from grass rather than milk, this intake increases sharply as the ewe’s milk supply declines. Most research and industry advice states that 12 weeks is the optimum weaning time. By 12 weeks the contribution of milk to the diet is small, but as this is still very nutritious, it is really worth considering the degree of competition between the ewe and lamb.

Finally there may be store cattle that can be marketed now, to further reduce the pressure on grazing.

Forage crops offer a solution to fill the forage gap when grass growth is insufficient. Various crops can be sown in to August/September, including stubble turnips, forage rape and hybrid brassicas which are fast growing and can be utilised quickly. It may be too dry to establish these crops now, but after the soil has some moisture, forage crops could be a solution. These could be sown after harvest in a stubble field or a grass field that would benefit from a break crop. Remember to assess the site and think of environmental conditions e.g. free draining soils with no steep slopes to minimise the risk of poaching and run off in the winter. Ensure the field offers shelter and water is supplied, to minimise poaching around water courses.

Conserved forage for the winter should be analysed for its nutritional value at least seven weeks after it has been preserved. There is no doubt the silage will be dry, but knowing the energy and protein content is essential when feed budgeting for different groups of livestock. This is the starting point to assessing if you have enough forage for the winter. Shortly the Farm Advisory Service will be issuing a booklet to all producers, which will guide livestock farmers through feed budgeting for the winter.

If forage is short there are alternatives that can sourced, such as potatoes, other vegetables, draff, and later on potentially roots (fodder beet, swedes). It is essential to speak to a nutritionist and ensure the planned diet for each batch of livestock will meet their nutritional requirements. Similarly if straw is short, there are alternatives for bedding such as sawdust, wood fines, peat, or grazing stubbles, etc. Start to investigate these options now and secure your supply for the winter.

This article has been funded by the Farm Advisory Service.