Shearing lambs: Recent discussions on finishing store lambs continue to raise follow-on questions, with a couple received this week on the merits of shearing lambs. Extensive research has been carried out in this area by Teagasc in recent years. Trials carried out in Mellows Campus Athenry show no production benefits in terms of daily liveweight gain from shearing lambs.

There can be advantages in terms of management, with shearing preventing hill lambs grazing outdoors from getting caught in briars while fully shearing lambs or crutching the area around the tail head and belly region can help to keep lambs cleaner where finished indoors or on forage crops and satisfy the requirements of the clean livestock policy (CLP).

Teagasc has also carried out trials in recent years to establish how much wool regrowth is required to be able to re-shear lambs if their fleece subsequently gets dirty and they are deemed unsuitable for slaughter (category C of the CLP).

Clippings were taken on a weekly basis across the loin, shoulder and belly region of Scottish Blackface and lowland lambs (Texel, Suffolk and Charollais). The results of the trial showed that for all breed types, four weeks’ regrowth was sufficient to allow lambs to be re-shorn if required pre-slaughter.

Temporary fencing and grazing management: Temporary electric fencing can be used to achieve greater utilisation from heavier covers and underpin positive performance. This is particularly beneficial where grazing heavy covers as if given unrestricted access to surplus grass, sheep will graze all the green leafy material first and then be forced to graze off the poorer quality grass at the base of the sward. While not always practical, the ideal approach with heavy covers is to split the available area into two- to three-day grazing blocks. In this situation ewes will be forced to graze lower-quality material for a shorter period before returning to better-quality grass.

The secret to operating such a system is to have a good current in the fence and possibly additional strands of wire to ensure ewes cannot break at the outset as if ewes break through a fence at the beginning it will be significantly harder to train them into such a system. Once accustomed, three strands of wire or two along by solid hedgerows should suffice.

Ewe intake requirements will be in the region of 1.5kg to 1.6kg DM/ha in the runup to and during breeding. This will reduce to closer to 1.3kg DM/ha later in the season or for early lambing ewes which are in mid-pregnancy.

Table 1 details the number of grazing days for a range of grass covers based on 100 ewes grazing a 1ha plot and offered 170kg DM/day.

Grass utilisation also needs to be taken into account and during times of poor utilisation ewes will need to be allocated a higher volume of grass or moved more regularly to maintain performance.