Dung beetles provide ecosystem services including reduced pasture fouling, increased nutrient cycling, and control of pest flies and gastrointestinal parasites.

Dung beetles have been estimated to save the UK cattle industry £367 million each year. Stopping the largely unnecessary treatment of adult cattle with anthelmintics could save the UK cattle industry an additional £6.2 million per year.

Dung beetles reduce livestock gastrointestinal parasites on pastures

Over the duration of a summer grazing season, dung insects can reduce the development and survival of cattle gastrointestinal parasites by approximately 30%

The effects of dung beetle tunnelling on soil infiltration and macropore creation (depth and width of the flow pathways) was evaluated. Soil infiltration rate increased in the presence of dung beetles, and infiltrated water reached a greater depth than control chambers without beetles.

Tropical dung beetles and those inhabiting arid environments close to upper thermal limits for survival are more vulnerable to climate change and heat stress. Dung beetles in sub-Saharan Africa have been shown to have a limited ability to adapt under climate stress, impacting ecosystem service (dung removal) efficiency.

Macrocyclic lactone (ML) and synthetic pyrethroid (SP) use on farms has significant impacts on dung beetle functional diversity. Tunnelling (paracoprid) dung beetles appear more sensitive to these chemicals than dwellers (endocoprids). This could negatively impact ecosystem function because tunnellers are thought to contribute more than dwellers to dung decomposition and soil health.

Dung beetle reproductive output is impaired by parasiticides .

Deltamethrin residues in cattle dung in sub-Saharan Africa increased mortality of adult dung beetles and reduced brood ball production and larval survival

In other research, dung beetles fed dung containing ivermectin had smaller ovaries, fat bodies and reduced motility

Contaminated dung buried by tunnelling dung beetles retains insecticidal effects, impacting below ground survival of immature stages .

Ivermectin residues can be present in manure even after storage.

Farmyard manure containing ivermectin was aged in the field for 4 months. Rainwater run-off from the manure heap was toxic to freshwater invertebrates . The aged manure was toxic to beetles and flies after spreading, and pasture growth from ryegrass seed was reduced by 18%

Veterinary medicines can end up in water bodies.

Anthelmintic residues were detected in 18% of groundwater sites surveyed in the Republic of Ireland . The majority of the residues detected belonged to the broad spectrum benzimidazoles commonly used to treat livestock for helminths and fluke.

Other recent work shows pet flea treatments polluting English rivers.

Dung beetles fed dung containing sublethal concentrations of parasiticides (far below what is found in cattle dung after treatment) accumulated chemical resides in their tissues. After ingestion, ivermectin moved rapidly through the gut, accumulating in the haemolymph (which bathes the other organs) and fat body tissues (used for metabolism).

This biomagnification could explain the acute toxicity of ivermectin on adult dung beetles, and sub-lethal effects that seriously affect sensorial and locomotor capacities even at very low doses.