Ectoparasites of brown rats (Rattus norvegicus) in Grenada, West Indies

Abstract

Background and Aim:Arthropod ectoparasites (mites, lice, ticks, and fleas) on common house rats or brown rats (Rattus norvegicus) are known to transmit zoonotic pathogens and diminish rat health. To the best of our knowledge, there is no published information regarding the prevalence of ectoparasites on R. norvegicus in Grenada. This study aimed to determine the prevalence and types of ectoparasites present on brown rats from Grenada.Materials and Methods:One hundred sixty-eight rats were collected live from the parishes of St. George and St. David, Grenada, from May to July 2017. Following euthanasia, external parasites were collected using fine combs, thumb forceps, and paper tape. Tape samples and free specimens were placed in containers with 70% ethanol. External parasites were evaluated using dissection microscopy.Results:Over 2000 ectoparasites were collected from 149 of the 168 trapped rats (88.7%). Ectoparasites identified included mesostigmatid mites (found on 84.6% of infested rats), fur mites in the families Atopomelidae and Listrophoridae (67.1%), Polyplax spp. lice (6.7%), fleas (3.4%), an unidentified larval tick (0.7%), and a mite in the family Myobiidae (0.7%). Infestation rates were higher in St. David Parish (86/89; 96.6%) than in St. George Parish (63/79; 79.7%) (p=0.001). When comparing sex and age, males had a marginal increase in infestation rate (83/89; 93.3%) compared to females (66/79; 83.5%) (p=0.054), and adults had an infestation rate of 90.7% (97/107) compared to juvenile rats who had a 66.7% (14/21) infestation rate.Conclusion:Brown rats in Grenada are heavily infested with ectoparasites, including known vectors of pathogens. Future studies will examine the prevalence of zoonotic pathogens in these arthropods.

First report of ectoparasites from black rats (Rattus rattus Linnaeus, 1758) in oasis regions from Algeria

“…were similar to those reported byThille et al (2019) who found that adults of R. norvegicus were the most infested by ectoparasites, with a prevalence of 90.7%, compared to juveniles (66.7%) with a significant difference (P = 0.008). Volf (1991) maintained that there is a relation between the level of infection of rats with the louse Polyplax spinulosa and the age and gender of rats.…”

“…which are dangerous to human health, due to the fact that they participate in the distribution of various pathogens zoonoses like Rickettsia spp. and transferring pathogenic agents to hosts causing diseases to human beings (Crystal, 1958;Lehan, 2005;Badiaga and Brouqui, 2012;Chakma et al, 2015;Thille et al, 2019). Also, X. cheopis was considered the main epidemic and enzootic vector of murine typhus Rickettsia typhi (Soliman et al, 2001).…”

“…The need to take into account the ecology and evolution of infectious diseases to understand their dynamics is increasingly accepted (Schrag and Wiener, 1995), particularly in the case of zoonosis caused by ectoparasites of black rats. Previous studies focused on the ectoparasites associated with black rats (Gaaboub et al, 1981;Soliman et al, 2001;Abd El-Halim et al, 2009;Bahgat, 2013;Nateghpour et al, 2013;Solanki et al, 2013;Asiry et al, 2014;Khajeh et al, 2017;Eslami et al, 2018;Thille et al, 2019) and zoonotic diseases attributed to these species as well as their involvement in its transmission to human and animals (Tijjani et al, 2020;Panthawong et al, 2020;Wang et al, 2020). No studies have been reported in Algeria on ectoparasites of rodents.…”

Deteksi Endoparasit Cacing pada Hepar Tikus Laboratorium (Rattus norvegicus) dari Sentra Peternak di Kabupaten Banyumas dan Kabupaten Purbalingga

“…felis, Myobia spp., Mesostigmata, Argasidae, Atopomelidae dan Listrophoridae. 6 Endoparasit yang diketahui menginfeksi tikus, antara lain Protozoa (Giardia muris, Entamoeba muris, Blastocystis spp., Eimeria spp., Trichomonas muris, Cryptosporidium spp., 7 Klossiella muris, K. cobayae 8 ), dan Helminth (Hymenolepis nana, Syphacia obvelata, Strongyloides ratti, Trichomonas crassicauda, Aspiculuris tetraptera, 7 Hymenolepis diminuta, 9 S. muris, 7,10 Nippostrongylus muris, 8 Eustrongylides excisus, 11 Gongylonema neoplasticum, 8 dan Cysticercus fasciolaris. [12][13][14] Keberadaan tikus laboratorium sangat diperlukan guna kepentingan penelitian biomedis atau observasi laboratorium.…”

Comparative analysis of the intestinal microbiome in Rattus norvegicus from different geographies

“…In a very recent study, we reported several opportunistic and pathogenic bacteria, including Bordetella, Clostridium, Corynebacterium, Empedobacter, Helicobacter, Limosilactobacillus, Macrococcus, Neisseria zaloph, Porphyromonas, Pseudomonas, Rahnella, Ralstonia, Rhodococcus, Rickettsiella, Streptococcus, etc. in the free-living urban R. norvegicus (Shah et al, 2023). R. norvegicus is also reported to be a host for a large number of blood-sucking ectoparasites, such as Polyplax lice, fleas, fur mites, mesostigmatid mites, etc., in the West Indies (Thille et al, 2019). Another study investigated free-living R. norvegicus for the presence of zoonotic viruses, parasites, and bacteria in Maryland, United States (Easterbrook et al, 2007).…”