Effect of ivermectin on the survival and fecundityb of <i>Euoniticellus intermedius</i> (Coleoptera: Scarabaeidae).

Abstract

The State of Veracruz in Mexico is one of the main cattle producers, and uses several veterinary products for disease and parasite control. For parasite control, ivermectin is one of the most frequently used substances. Nevertheless, even though previous research conducted in other countries has found that this product has negative effects on beneficial coprophagous fauna, no studies have described its effects on coprophagous insects at a local scale in Veracruz, Mexico. This study evaluated Euoniticellus intermedius survival, fecundity, fertility and preimaginal development under laboratory conditions when ivermectin was added to cattle dung at three different concentrations. The design included two controls (spiked dung), and the following product concentrations: 0.01, 1.0 and 100ppm, which were homogenized with wet cattle dung. 20 female-male E. intermedius couples between five and 15 days old were used and kept at 27°C, 70% RH, and 12h light for 10 days. The survival of all specimens, the fertility of 20 females and the gonadal maturity of 17 males were verified. The larval development in 162 pieces of brood-mass was examined, and a total of 974 larvae developed and reached adulthood. The highest ivermectin concentration was toxic at 1.0ppm dose, the survival of adults was reduced to almost the half, and at 100ppm, total mortality was observed. The effects on specimen reproductive systems showed that the ovary was not affected, that the testicle size increased, and that the fecundity and weight of brood-masses were reduced. Pre-imaginal development increased 0.5 times at 0.01ppm concentration, and the width of the cephalic capsule in third instar larvae diminished. The prolonging of development time may cause a phase lag in the field activity cycle, this lag may reduce the number of E. intermedius individuals and the efficiency of the environmental services that they provide.

Effects of grazing intensity and the use of veterinary medical products on dung beetle biodiversity in the sub-mountainous landscape of Central Italy

“…When it comes to the impact of VMPs on dung beetles, however, the majority of research has been carried out in the laboratory, with the focus on the effects on a single or just a few species (Verdú et al, 2015; Cruz-Rosales et al, 2012; Hempel et al, 2006; Wardhaugh & Rodriguez-Menendez, 1988). Nevertheless, it is important to evaluate the impact of different grazing intensities in order to determine the optimum level for dung beetle conservation.…”

Morphometric Modifications in Canthon quinquemaculatus Castelnau 1840 (Coleoptera: Scarabaeinae): Sublethal Effects of Transgenic Maize?

“…Sublethal effects of chemical compounds associated with agricultural practices have been observed in dung beetles. Dung beetles fed with feces containing Ivermectin (a chemical product used to control parasites in cattle) presented behavioral changes, increased developmental time, reduced fecundity and oviposition, and reduced cephalic capsule size [ 18 , 19 , 20 ]. Behavioral and physiological changes were also described in dung beetles fed with cattle feces containing transgenic maize.…”

Reproductive sublethal effects of macrocyclic lactones and synthetic pyrethroids on the dung beetle Onthophagus similis

“…Significantly fewer brood masses were made by E. intermedius in dung collected from cattle 1 to 14 days after a 200 μg/kg injection of ivermectin (Kruger and Scholz, 1997), and when E. intermedius was exposed to dung spiked with 0.1 ppm of ivermectin (Cruz Rosales et al, 2012).…”