Earlier housing of ewes or lambs for finishing is looking like a very real prospect for many farmers.

While higher temperatures are underpinning above-normal grass growth and may help some farmers to extend the grazing season, it is likely that for many housing may come earlier than normal. An added threat to existing grass supplies is the sharp drop in levels of grass utilisation caused by recent torrential rainfall.

As such, it is prudent to have plans in place, if required, and this includes reviewing straw supplies and fodder reserves.

Looking at straw firstly, lowland ewes will require approximately 7kg straw for bedding each week to absorb all urine, while the requirement for hill ewes is significantly lower at 4kg to 5kg.

Looking at this in an easier light, a typical 4x4 round bale of straw weighing 14kg will generally be sufficient to provide bedding for 18 to 20 lowland ewes and 30 to 35 hill ewes.

This calculation is based on a silage diet. Higher volumes of hay and haylage were saved this year and where this is the main diet for ewes then the bedding requirement may be reduced by 20% to 30%.

It is also worth considering that straw was saved in excellent condition this year which should optimise absorbency.

For users of large volumes of straw bedding, straw choppers/blowers are worth considering.

There will also be savings in labour and potentially in straw usage where it is spread using a straw chopper.

Reports vary on the volume of straw that can be saved with some claiming savings of over 10%, while there are very definite savings in labour input.

Adequate ventilation will also help keep bedding drier and any leakages in drinkers, etc, should be rectified immediately.

Lambing considerations

Account also needs to be taken when calculating straw requirements of higher usage during lambing.

Typically, four to five bales need to be factored in for every 100 ewes for bedding lambing pens where ewes are turned out within 24 to 36 hours of delivering lambs. In high prolificacy flocks, this requirement should be increased by 20% to 30% to take account of the higher average litter size and need to keep lighter lambs indoors for longer.

Weight of bales

The best way to accurately assess volumes of straw available is by weight as consideration needs to be given to the variance in weight that can exist between bales.

Round 4 x 4 bales typically weigh 150kg on average but well-packed bales can weigh 140kg to 180kg with poorly packed bales as low as 120kg. The lower moisture content in straw this year will also have an influence. Rectangular 8 x 4 x 3 bales weigh about 360kg (range 350kg to 380kg), while 8 x 4 x 4 bales vary more and can weigh from just below 500kg to upwards of 600kg with an average weight typically of 540kg to 550kg.