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Grazing strategies by reducing reliance on anthelmintics.

Grazed grass is the cheapest and most natural ruminant feed. Up to half that grown is commonly wasted. If managed correctly however, grazed grass can provide 85% and 95% of natural energy requirements of beef and sheep systems respectively. Input costs and reliance on bought-in feed can be dramatically reduced. Many producers finish lambs and cattle purely off pasture and conserved forages often earning a premium. They can also reduce other costly inputs such as anthelmintics and provide the market with naturally and ethically produced food. There are costs associated with better grass utilisation with higher fencing, water provision and management etc. but benefits far outweigh the costs

Differing approaches to grazing as highlighted in the table, can almost double grass yield which in turn increases stocking potential. A move to one grazing system entirely may be impractical and a combination can be applied still with yield improvements.

Understanding grass growth and the host of factors that affect it is key. Growing as much as you can is pointless if not utilised. Optimum grass sward height for cattle and sheep differ. Measurement by eye, against your boot or by sward stick etc. monitors growth from week to week. Plate meters are an excellent management tool and so accurate they are second only to cutting, drying and weighing pasture samples so quickly establish quantity of dry matter available in a grazing paddock taking measurements as you walk.

Gaining that illusive ‘extra bite’ for lactating ewes or growing youngstock can be achieved by grazing the same areas more efficiently using a Rotational or Paddock type systems. It may be daunting to set up but electric fencing easily incorporates with existing fence lines creating separate blocks quickly so you can give it a go. The use of Speedrite Unigizer™ power units gives the option to use mains, battery or solar power with the latter only requiring daylight to recharge batteries. Modern systems also provide more power output from less input with Cyclic Wave® technology keeping stock fenced in.

Assuming stocking rates increase, over reliance on anthelmintics for worm and fluke control can be an issue. Effective grazing management can assist in this too if planned. Simply rotating grazing pastures with cattle one year and sheep the next reduces the parasite burden. Mixed grazing reduces species density and the worm build up but compromises to optimum sward height must be made. Forage areas partially grazed or even considered in a grass ley in your arable rotation helps. Permanent pasture in an arable rotation for reduced parasite build up and less anthelmintic use should not be ruled out too.

Grouping lambs in tight age groups after lambing as opposed to one large flock has benefits when it comes to assessing worm treatment requirements especially using faecal egg counts (FECs). Other management actions are easier, such as adhering to withdrawal periods post treatment. Also, grading, weighing and batching more even batches of finished lambs is easier too.

Moving weaned lambs onto forage aftermaths reduce worm burden exposure and provides a good supply of fresh grass. Do not move immediately, if they are drenched, carry some susceptible worms as well as resistant ones to the new pasture so you are not breeding resistance. Managing worm population is the goal not total eradication. Mature ewes in good body condition on the other hand need to remain on these high-risk pastures, ingesting large quantities of infective larvae and are effectively killing them reducing the overall level of contamination on that pasture for later in the season and/or next spring.

In cattle, a dairy heifer study found achieving breeding weights took three months longer when burdened with worms, costing £260/head extra. Using mixed age grazing of cattle reduced worm burdens as older cattle excrete lower worm egg concentrations due to more resistance. The Leader/Follower system on rotational grazing allows young stock at turnout to graze ahead of older animals and keeps them in front of the worm burden and impressive growth rates of 0.81kg compared to 0.39kg per day were observed. Delayed turnout of cattle has also reduced young-stock worm burdens but considered impractical, although grazing forage aftermaths with stock remaining housed and eating excess overwintered forage an option.

Areas of the farm utilised for forage and arable production often have weaker permanent fencing and once again electric fencing can provide a quick and movable solution. Large areas once cut for forage can be grazed. Pastures can also be split as required as grass growth dictates, using temporary electric fencing in conjunction with permanent boundary fences.

Liver fluke infestation (fasciolosis) is a constant problem during late autumn/winter especially in the wetter UK areas but slaughterhouse liver condemnations indicate fasciolosis is now widespread and increasing. Permanent exclusion from snail-infested areas or at least the boggiest areas should not be ruled out as farm conservation schemes rule out drainage etc. Compensate with better stocking rates elsewhere in improved grazing regimes (Source; SCOPS).

Regular weighing of grazing animals ensures DLWG targets are met and assist with market selection at optimum weights and reveal worm burdens.

Farm Resource Management (FRM) solutions from Tru-Test include electronic Plate Meters automatically recording each reading displaying number of samples taken, average pasture height and cover. Tru-Test also supply weigh scale indicators, EID Readers and Load bars including portable solutions. Speedrite electric fencing incorporates unique market leading technology including Unigizer™ powered energisers via mains, battery or solar. They are highly weather resistant and require less power input providing more power output with Cyclic Wave® technology. Hayes hand tools from New Zealand are the choice of fencing contractors worldwide with wire strainers, dispensers and crimpers for both permanent and temporary conventional and electric fencing.

Animal Health Delivery Systems (AHDS) from Simcro and NJ Phillips ensure animals are correctly medicated with anthelmintics with

animal welfare and lower resistance build up considerations.

Available from your local UK stockist.

More information and a store locator is available online at or call Datamars on 028 2076 8696.

Info sourced from SCOPS, AHDB & Professor Andy Forbes Glasgow Vet. Med. School/COWS


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