Coprological examination of gastrointestinal (GI) parasites and their life stages in humans and dogs and in soil was carried out in a low income tea estate community in the Central Province. This community has limited access to public health facilities and veterinary services and lives in close contact with free roaming dogs. Parasites in faeces were isolated and identified morphologically and morphometrically using microscopical methods, followed by molecular confirmation of selected protozoans. Soil samples collected from the neighbourhood were analyzed for soil inhabiting parasitic stages. Of the 50 dogs examined, 86.0% was infected with one or more parasites with a significantly higher number of dogs having mixed infections than single infections. Dogs harboured 13 GI parasites, of which nine were known zoonotic species: Toxocara canis, Strongyloides sp., Entamoeba coli, hookworm, Trichuris sp., Giardia duodenalis, Spirocerca lupi, Toxascaris sp., and Taenia sp. Additionally Entamoeba histolytica, coccidia, unidentified trematodes and cestodes were also found in dogs. Six types of GI parasites were identified in humans, of these four types, E. coli, G. duodenalis, Strongyloides sp. and Blastocystis sp. were potentially acquired from animals. A total of 16 soil samples were analyzed, of which 44.4% were carrying infective nematode L 3 larvae and eggs, cysts of E. coli and eggs of T. canis all of which were zoonotic. High prevalence of zoonotic infections in dog population and in soil poses a serious health threat to the community. Results highlight the importance of regular deworming of both humans and dogs and reducing environmental contamination, a One Health approach incorporating veterinary and public health interventions in the surveillance and management of zoonoses.

Amblyomma integrum is a hard tick infesting mainly buffalo and cattle and has been identified as an agent of human otoacariasis in Sri Lanka. Data on the life cycle pattern of A. integrum were collected by experimental infestation on New Zealand white rabbits under laboratory conditions. Wild-caught females laid 55-7389 eggs for 2-35 days after spending a latent period of 10-25 days. Egg incubation period was 31-105 days and the newly emerged larvae started feeding after 4-11 days. Larvae dropped off after feeding and they moulted into nymphs after 10-16 days. Nymphs actively fed on rabbits for 4-8 days and dropped off. Engorged nymphs took 11-25 days for moulting before emerging as adults. The male:female sex ratio of the adults moulted under laboratory conditions was 11:9. All the stages showed periodicity in engorgement and dropping off. The three-host life cycle was completed within 74-245 days with an average of 152.9 days. The mean Reproductive Efficiency Index (REI) and Reproductive Aptitude Index (RAI) were 3.6 and 1.1, respectively. Females hatched in the laboratory did not successfully feed on New Zealand white rabbits. The wild-caught females which fed on buffaloes had prolonged pre-oviposition and oviposition periods, low REI, low RAI and low eclosion under controlled laboratory conditions compared to other tick species. Although larva and nymphs of A. integrum successfully fed on New Zealand white rabbits under laboratory conditions, full life cycle was not completed because the adult females did not feed on rabbits.

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Hyalomma isaaci and Rhipicephalus microplus are two common hard tick species infesting buffalo and cattle. Biological data on the ticks' life cycle were collected by experimental infestation on New Zealand white rabbits (Oryctolagus cuniculus) under controlled conditions (70%-80% Relative humidity and 27 ± 1 ᵒ C Temperature). Life cycle parameters including latency period, oviposition, feeding, moulting periods were determined and the Mean Reproductive Efficiency Index (REI) and Reproductive Aptitude Index (RAI) were calculated. Females of H. isaaci and R. microplus started oviposition after 3-14 days and 5-8 days, respectively. Hyalomma isaaci laid 15-6,166 (1600.8 ± 1940.9) eggs in 1-24 days while R. microplus laid 19-1,535 (434.2±344.8) eggs in 1-11 days. Emerged larvae of H. isaaci spent 19-47 days in incubation and moulted on-host. Nymphs dropped after feeding for 15-21 days, subsequently taking 14-18 days to moult into adults. Females fed for 8-10 days, and reached a maximum engorgement weight of 127.0 mg. The non-parasitic phase of R. microplus was 29-57 days, while the parasitic phase was confined only to larval engorgement and moulting into nymphs taking of 8-14 days. The REI/RAI was 7.1/3.6 and 8.3/5.1 for H. isaaci and R. microplus, respectively. Hyalomma isaaci completed its two-host life cycle within 62-166 days while R. microplus could not complete its life cycle because the nymphs did not feed on rabbits and therefore, none of them moulted into adults. The New Zealand white rabbit was not an appropriate laboratory host for the mature stage of R. microplus even though it was a suitable host for H. isaaci.

Amblyomma integrum Karsch, 1879 (Acari: Ixodidae) is one of four Amblyomma Koch, 1844 species with eyes found in southern India and Sri Lanka. The immature stages of this species were poorly described. Therefore, accurate identification is difficult. Here we re-describe the male, female, nymph and larva of A. integrum and illustrate all the stages in greater detail for the first time. A set of diagnostic morphological characters is defined to distinguish this species from other sympatric species of eyed Amblyomma in any parasitic stage of development. Adults of A. integrum parasitize mostly various larger mammals whereas nymphs and larvae use mostly larger and medium mammals. Amblyomma integrum is recorded from India (Andhra Pradesh, Goa, Karnataka, Orissa and Tamil Nadu States) and throughout Sri Lanka.

Nosomma monstrosum (Nuttall & Warburton) is a hard tick infesting mainly buffalo and cattle in Sri Lanka. Biological data on the life cycle pattern of N. monstrosum were collected using experimental infestation on New Zealand white rabbits under laboratory conditions. The three-host life cycle was completed within 64-102 days. Eggs hatched after 20-29 days of incubation and the larvae hatched out started feeding which lasted for 2-4 days. After a moulting period of 8-11 days nymphs emerge and they actively fed for 2-4 days. Subsequently the nymphs took 15-18 days for moulting before emerging as adults. Freshly moulted females fed for 7-8 days and remained latent for 4-5 days before starting the oviposition. Females laid 3864-12,520 eggs for 11-17 days. The male: female sex ratio was 8:3 in the adults which were moulted under laboratory conditions. Strong positive correlations were found in female weight with number of eggs laid and REI. Females raised from the first generation of eggs had higher oviposition periods, higher REI, laid ten times more eggs, and lower pre-oviposition periods compared to those collected from the wild. When a suitable host is given, N. monstrosum could successfully complete its three-host life cycle under laboratory conditions.