‘Super-rats’ unwittingly bred on farms says study

• Rats resistant to rodenticides

• Traditional poisons don’t work

• New product is now available

Most farmers don’t know if their farm is in an area of known rodenticide resistance, reveals a survey by pest control solutions company BASF.

The research – which looked at on-farm rodent control measures and rodenticide usage – found that an overwhelming 88% of those surveyed were unsure if resistance to certain baits had been reported in their region.

When asked, one third of farmers were not aware that rodenticide resistance was even an issue to consider when selecting which bait to use on their land, despite over 90% of farmers having used rodenticides on their farm in the past 12 months.

In fact, farmers could be unknowingly contributing to the spread of “super rats,” which are resistant to baits containing first generation anticoagulants – as well as those containing  second-generation anticoagulants difenacoum and bromadiolone.

 BASF key account manager Helen Hall said: “The issue of rodenticide resistance is problematic for many farmers, who may be unknowingly contributing to the pest problems on their farms.”

Heavy cost

Although traditional difenacoum and bromadiolone baits should control non-resistant rodents, resistant rats could spread disease, destroy equipment, and contaminate animal feed – ultimately costing farmers a lot of money.

“Growing populations of “super-rats” will be unaffected by these traditional poisons and will continue to reproduce, thus breeding more rats with the mutated gene and creating an even wider issue of resistant rodents throughout the area.”

The findings come as BASF launches its new “resistance breaking” rodenticide Selontra, into the rural market. It features the active ingredient cholecalciferol, used to break the cycle of resistance and control infestations in as few as seven days.

Cholecalciferol, the active ingredient in Selontra, causes death by depositing too much calcium in the blood. It has a stop feed effect, causing rodents to cease feeding approximately 24 hours after a lethal dose has been achieved

Ms Hall said: “It also stops them moving around, minimising any further cost or risk impact such as the spread of disease, reducing damage to property, and preventing additional bio-security contamination.”

To help raise awareness of rodenticide resistance and encourage best practice across UK farms, BASF has launched a new digital portal offering farmers an interactive rodent control training programme.

Developed by rodent infestation expert Oliver Madge, the Real Results Virtual Farm CPD portal, explains different areas of rodent control. It then asks users to complete a CRRU-recognised exam for the Safe Use of Rodenticides.

Ms Hall said three quarters of farmers said they are keen to learn more about rodent control on farms. “We hope this new platform will enable many to gain more knowledge and understanding of biology, behaviour and best practice.”