Controlling rodents: The need for speed

According to BASF, you can prevent costly rodent damage and control infestations in as few as seven days this winter.

Farmers can stop rats and mice from moving around their site after 24 hours and gain complete control in as few as seven days, just by choosing the right rodenticide, according to pest control manufacturer BASF.

When signs of rodents are spotted, it’s important farmers act fast to reduce the risks posed by these common pests. Having rats and mice active on farms comes with a host of issues, including:

• Damage: Rats and mice need to gnaw, and often choose to do so on electrical cables which can result in damage to expensive equipment and machinery, and in some cases even cause res to breakout.

• Disease: Rats carry up to 45 diseases, posing a serious risk to the biosecurity of the whole food chain. Salmonella is an ever present (and possibly increasing) risk within pigs and poultry and rodents are a contributing factor to the spread of this disease.

• Loss

of animal feed and grain:

It is estimated that one rat can eat and contaminate 100kg of stored grain and feed annually, so 200 rats will destroy a massive 20 tonnes per year.

• Spread of infestation: In the right conditions, rats and mice can reproduce every three weeks and from one breeding pair it is possible for over 1,500 o spring to occur within six months.

Choosing a bait

A recent national rodent control survey showed that 92% of farmers have used rodenticides on their farm in the last year, but with so many rodenticide baits on the market, how do you choose which bait is best?

From anticoagulants to nonanticoagulants, and hard blocks, soft blocks, pellets, paste and grain available, it can be di cult to decide which is the most e ective solution.

One of the most important factors to consider, though, is the speed of control. Anticoagulant rodenticides usually take 21–28 days to control an infestation, which means that these risks of damage, loss and contamination continue to occur around a site for some weeks after the initial treatment. BASF has introduced a new non-anticoagulant rodenticide, Selontra, to combat this, using the active ingredient cholecalciferol to stop rodents in their tracks.

The soft block bait causes death from hypercalcaemia; the accumulation of too much calcium in the blood. This results in rodents stopping feeding, on both the bait and any available food on the farm, 24 hours after consuming a lethal dose, quickly putting a stop to disease, contamination and damage to the site.

Sharon Hughes, BASF pest control solutions specialist, commented: “Not only does Selontra have a stop feed e ect, causing rodents to cease feeding once a lethal amount of bait has been eaten, it is also e ective on rats and mice with rodenticide resistance, non-bioaccumulative and readily metabolised by rodents, balancing performance and environmental impact.

“Thanks to these fast-acting results, Selontra o ers the added bene t of reducing the time the bait is in the environment as it is applied on site for shorter-periods of time –typically no more than seven days. This also means that farmers’ valuable time can be spent focusing on their many other daily tasks!”

Best practice

To help raise awareness of rodenticide resistance and encourage best practice across UK farms, BASF has launched a new digital portal o ering farmers the chance to gain CPD points through an interactive rodent control training programme. Find out more about Selontra and gain CPD points at www.basf-ruralhygiene. com/rodent-course

Reducing the risk to non-targets

With the use of all pesticides, reading and following the product label is a strict requirement. With rodenticides, however, it is also essential to complete an Environmental Risk Assessment (ERA). Think Wildlife’s

Campaign for Responsible Rodenticide

Use (CRRU) reported that routine monitoring from 2016–2021 found rodenticide traces present in nearly 90% of barn owls, demonstrating that more needs to be done to reduce the risk to all nontargets.

If all non-chemical preventative methods have failed, an ERA should be completed before applying rodenticides. This ERA should focus primarily on non-target species, those being animals which may consume any baits applied (known as primary poisoning) that are not rats and mice, and those which may consume poisoned rodents through predation or scavenging (known as secondary poisoning).

Which active ingredient to use is an important consideration as part of a planned approach to minimise and prevent both primary and secondary poisoning. Second Generation Anticoagulant Rodenticides (SGARs) have been termed ‘bioaccumulative’, simply meaning there can be a buildup of these rodenticides within the body, which occurs with repetitive feeding on the rodent bait or poisoned rodents. The non-anticoagulant active ingredient, cholecalciferol, which is used in Selontra, is neither bioaccumulative nor persistent in the environment.

It also goes without saying that all non-target species should be prevented from accessing the rodenticide bait, either by using a securable bait in a lockable bait box or by using the covered and protected approach, that is attaching bait to an object and covering with a sturdy item such as palettes, timber or tyres. Frequent searching for and disposing of dead rodents throughout the rodenticide treatment helps to prevent secondary poisoning, and ensuring all bait is removed following the treatment plan is essential. FG