MACROPARASITE COMMUNITIES OF WILD RATS FROM ISLAND AND COASTAL HABITATS IN PENINSULAR MALAYSIA

The occurrences  of  macroparasites communities  in363wild ratsof two  urban coastalcities (Kuantan and Malacca)and two islands (Carey  Island and Penang)of Peninsular Malaysia  wererecordedbetweenMay  2010  to  August  2011. The wild  ratsfrom  both habitatscomprised ofmainly commensal rat species namely;Rattus norvegicus, Rattus rattus  diardii,  Rattus  tiomanicusand Rattus  argentiventer. Overall,  higher  numbers  of females  (60.3%)  were  captured  compared  to  males  (39.7%) with  more  adults  (87.9%) compared to juveniles  (12.1%).The ratswere infected witha minimum of one species and a maximum of six species of ectoparasiteswhile up to five species of endoparasiteswere  seen  in  each  rat.InR.  norvegicusthe  highest number  of  ecto  and  endoparasites infestation/infection was seen respectively.There  were  no differences  inthe types  of macroparasites  recovered fromboth  coastal and  island rat populations. Overall,  ectoparasites  diversity  index  was  low  for  all  sites, although  Carey  Island  recorded  higher  index  compared  to  other  locations  with 8 numbers of species. Nine cosmopolitan ectoparasitespecies were recoveredin total with 5mite    species,(Laelaps    nuttali,    Laelaps    echidninus,    Ornithonyssus    bacoti, Listrophoroidessp.,  Laelaps  sculpturatus) 2lice,(Polyplax  spinulosa,  Hoplopleura pacifica,)one  flea(Xenopsylla  cheopis)and one  tick(Ixodes granulatus).Host sex (male  and  female)  and  host  age  (adult  and  juvenile)did  not influence  ectoparasite infestation  onthe  rat  population.  However,  seasons playeda  significant  role with Ornithonyssus  bacoti, Laelaps  sculpturatus,Polyplax  spinulosa,Hoplopleura  pacificaand Ixodes granulatus with higher infestionduring wetcompared to dry season.Endoparasites    infections    comprised    entirely    of    cosmopolitan    species,    namely Nippostrongylus   brasiliensis,   Angiostrongylus   malaysiensis,   Capillaria   hepatica, Mastophorus  muris, Heterakis  spumosa,  Hepatojarakus  malayae, Syphacia  muris, Taenia  taeniaeformis, Hymenolepis  diminuta andRodentolepis (=Hymenolepis)nana. Species  diversity index  was  low  in  all  locations. Host  sex  influenced  endoparasitic infection only    forCapillariahepatica,    Syphacia    murisand Rodentolepis (=Hymenolepis)nanawhile other helminths(Hepatojarakus   malayae,   Taenia taeniaformis, Rodentolepis (=Hymenolepis)nana)  showed  significant  effects  between host ages. Season also played a significant role determining diversity and prevalence for most endoparasitespecies with higherinfectionobservedduring the dry season. Despite   low   diversity,seven   ectoparasites(Laelapsnuttali,Laelapsechidninus,Ornithonyssus bacoti,Polyplax spinulosa,Hoplopleurapacifica,Ixodes granulatusand Xenopsylla  cheopis)  and5helminths  species(Capillaria  hepatica,Angiostrongylus malaysiensis,Hymenolepis diminuta, Taenia taeniaeformis, Rodentolepis (=Hymenolepis)nana)recoveredwere  zoonotic. The  close  association  between  the  ratpopulationswithhuman may facilitate the transmission ofzoonotic parasitescirculating in  these  ecosystems. Therefore,  long  term  monitoring  of  the  rodent  population  is necessary in order to predict future disease prevalence.