Rodent Battles: In small doses

Brandon Kraupp, owner of Romex Pest Control in Plano, Texas, always used more than one rodent control product. He rotated such products so rats and mice wouldn’t develop resistance to any one active ingredient.

But after trying Selontra rodent bait by BASF six months ago, Kraupp stopped buying other rodent baits. He says he now uses Selontra exclusively. The product doesn’t create resistance challenges, as Selontra’s active ingredient, cholecalciferol, is effective against anticoagulant-resistant rodents.¹ “I’m getting a lot better results for all of our customers with Selontra,” Kraupp says. “It’s a good feeling when a product actually performs and does its job.”

The stop-feed action of Selontra’s active ingredient, cholecalciferol, makes a little go a long way — rodents eat only enough for a lethal dose, leaving more for the rest of the colony.^2,3 This stop-feed action causes rodents to lose their appetite, leaving more bait for the rest of the colony and allowing subdominant rodents to feed sooner.

BASF field trials have shown that Selontra brings infestations under control in as few as seven days.⁴ This means pest control companies save money and time, because they don’t need as much bait, and technicians don’t have to return as often to refill bait stations.

Romex faced its biggest challenge on a residential lot infested with Norway rats (Rattus norvegicus). The homeowner had initially contacted him about 18 months ago, saying contractors clearing land next to her house had driven scores of rats out of sunflower fields and onto her property.

Romex first positioned bait stations using a competitive bait on the site. The plan was to return once a quarter to replenish the bait. However, the infestation was so extensive that the company’s technicians had to refill bait stations every 18 to 20 days. The battle raged for months without significant decline in the rodent population.

Then, in spring 2018, Romex tried Selontra on the property. Each time technicians returned to check the bait stations, they found the rats had eaten less and less of the Selontra. Yet they continued to find dead rats. “There were so many rats,” Kraupp says. “We were expecting to see the bait stations empty.”

While Kraupp didn’t realize it right away, he was seeing the effects of the stop-feed action of cholecalciferol. As a result, following initial treatment and control of the infestation in accordance with the label, the technicians were able to cut back their visits to once every two months. “The best part was that we had much better results,” Kraupp says. “Selontra controlled the population so much. It was nice to have a product that helped us solve the problem in a time effective manner.”

_{¹ E.F. Marshall. Cholecalciferol: A Unique Toxicant for Rodent Control. Proceedings of the Eleventh Vertebrate Pest Conference 1984. pp. 95-98.}

_{² Prescott, C.V., El-Amin, Vusa, and Smith,R.H. “Calciferols and Bait Shyness in the Laboratory Rat.” Proceedings of the Fifteenth Vertebrate Pest Conference 1992. Paper 64.}

_{³ Whisson, Desley, “Rodenticides for Control of Norway Rats, Roof Rats, and House Mice.” University of California Cooperative Extension, Poultry Fact Sheet No. 23, 1996}

_{⁴ U.S. Field Trials (Indiana Grain Farm, 2017; NC Pig Farm, 2016; New Orleans, LA, Urban Study, 2016) demonstrated control of rats and mice infestations in as few as seven days, in the presence of abundant, competing food sources.}