Lithium Chloride Shows Effectiveness against the Poultry Red Mite (Dermanyssus gallinae)

Abstract

The poultry red mite (Dermanyssus gallinae) is the main pest of poultry, causing severe problems by being a vector of several animal and human pathogens. The number of miticides is few, and their efficacy in practice implies problems of residues and resistance; therefore, the demand for a new and safe agent is constant. The present publication investigated the effectiveness of lithium chloride under in vitro conditions on poultry red mites. This chemical currently appears to be one of the most promising alternatives to study amongst potential applicants to treat varroosis, a fatal disease of honey bees. In Experiment I, the previously used experimental doses (5.52 M, 2.76 M, 1.38 M) on Varroa mites confirmed their in vitro activity on the poultry red mite. Three event times (uncontrolled movement, immobilisation and death) were recorded to base the response to treatment for each concentration. In Experiment II, the LD 50 value was calculated, i.e., the value at which 50% of the mites were killed by the treatment. This Experiment showed that the LD50 of lithium chloride = 0.265 M in the poultry red mite. It is to note that the study remained restricted to in vitro confirmation of lithium chloride’s effectiveness on the parasite. Thus, further extensive studies are needed to decide whether it has any relevance in practice against D. gallinae, and also to assess potential residue problems that could affect poultry products.

Isotopic and Elemental Fingerprint of Edible Egg Parts—The Health Risk Assessment Based on Potentially Toxic Elements Content

“…Foods of animal origin are rich in naturally occurring micro-elemental lithium, such as milk, poultry meat and eggs (>7000 µg dry matter) [ 23 ]. As cereals constitute an important part in the poultry diet, and grains contain a low content of boron, 2 mg/kg of B are recommended for hens’ feed, even if B is not considered an essential micronutrient for fowls and other farm animals [ 24 ].…”

Evaluation of the Acaricidal Activity of Lithium Chloride against Tetranychus urticae (Acari: Tetranychidae)

“…Lithium was also found to be effective for poultry red mite. Lithium concentrations of 5.52 M, 2.76 M, and 1.38 M were also tested on poultry red mite (Dermanyssus gallinae) recently [45]. The time needed for the death of 50% of the animals-i.e., reaching LD50-was 25, 45, and 134 min for the 5.52 M, the 2.76 M, and the 1.38 M concentrations, respectively, and similarly significant differences occurred for reaching the LD90 stage (64, 87, and 312.5 min for the 5.52 M, the 2.76 M, and the 1.38 M concentrations, respectively).…”

“…In addition, a feasible technological solution is already available should lithium become a widely authorised veterinary active substance in the near future [44]. Recently, it was revealed that lithium chloride also exerts effectivity on the poultry red mite [45]. To date, however, research on the acaricidal feature of the biometal has remained limited to its possible veterinary application.…”

Efficacy of In Vitro Lithium Chloride Treatments on Dermacentor reticulatus

“…Two separate tests were conducted to describe the dynamics of response and to determine the LC 50 values for the lithium chloride in dog ticks. In Test I, aqueous lithium chloride solutions (deionized water, LiCl a.r, Szkarabeusz Kft.,Pécs, Hungary) were used in the following concentrations: 5.520 M, 2.760 M, and 1.380 M, similar to those applied in previous studies on V. destructor and D. gallinae [ 8 , 10 ]. The dog ticks were immersed in 1 mL solutions in Eppendorf tubes (Thermo Fisher Scientific, Waltham, MA, USA) and slightly vortexed for 10 s to remove any air bubbles on the animals, ensuring an even contact exposure.…”

“…Later, it was confirmed that its strong biocidal effect contributes to the high efficacy of the varroacide agent [ 8 ], and techniques relevant to beekeeping practice have been published for lithium-based Varroa control treatments [ 9 ]. Additionally, it has been recently revealed that lithium is effective against the poultry red mite in vitro [ 10 ].…”