The host preferences of eight species of anophelines were studied in two coastal Malaysian villages, Kampung Permatang Rawa and Sungai Udang Kecil, by seven 12-hour catches in each village. Collections were made concurrently from a human-baited net trap, a cow-baited net trap and by human-bait landing catches. Anopheles campestris was attracted almost equally to man and cow, but An. lesteri paraliae, An. nigerrimus, An. peditaeniatus, An. sinensis, An. indefinitus, An. subpictus and An. vagus showed a strong preference for the cow bait. The human-bait landing catches were more productive than the human-baited net trap, which attracted very few mosquitos. Seven more all-night catches were made at each village employing only the cow-baited trap, and the combined data were used to plot the biting-cycles of each species at each site. Although the biting-cycles at the two localities were in general agreement, there were notable differences. At Sungai Udang Kecil, where the collection site was relatively sheltered, several species showed a steady decline in numbers from sunset to sunrise. At Kampung Permatang Rawa, on the other hand, where the site was more exposed and close to the sea, the same species showed a bimodal pattern of activity with an early evening peak followed by a decline then a period of increased activity before sunrise rising to a second, lesser peak at 0500-0600 hours.
Genetic characterization of Theileria species infecting bovines in India was attempted targeting the 18S ribosomal RNA region of the parasite. Blood samples of bovines (n = 452), suspected for haemoprotozoan infections, from 9 different states of the country were microscopically examined for Theileria species infection. Four Theileria spp. positive blood samples from each state were randomly utilized for PCR amplification of the 18S rRNA gene (approx. 1529 bp) followed by cloning and sequencing. The sequence data analysis of all the 36 isolates revealed that 33 isolates had high sequence similarity with published sequences of T. annulata, whereas 3 isolates (MF287917, MF287924 and MF287928) showed close similarity with published sequences of T. orientalis. Sequence homology within the isolates ranged between 95.8 and 100% and variation in the length of targeted region was also noticed in different isolates (1527-1538 nt). Phylogenetic tree created for T. annulata sequences revealed that a total of 24 Indian isolates formed a major clade and grouped together with isolates originating from countries like China, Spain, Turkey and USA. Remaining 09 isolates clustered in a separate group and were closely related to the TA5 isolate of T. annulata (a new genotype) originating from India and also with the isolates from East Asian countries like Japan and Malaysia. All the three T. orientalis isolates had minimal intraspecific variation (99-100% homology) amongst themselves. Further, in the phylogenetic analysis T. orientalis Indian isolates were found to cluster away from other 14 isolates of T. buffeli/sergenti/orientalis originating from different countries (Australia, China, Indonesia and Spain). However, these 3 isolates clustered together with the T. buffeli Indian isolate (EF126184). Present study confirmed the circulation of different genotypes of T. annulata in India, along with T. orientalis isolates.
Antibodies to the protozoan parasite, Toxoplasma gondii were assayed in sera of 200 goats, 100 pigs, 126 cattle from various states of Malaysia, and 135 dogs and 55 cats around Ipoh region using an indirect fluorescence antibody test (IFAT, cut-off titer 1:200); antibodies were found in 35.5% of goats, 14.5% cats, 9.6% dogs, 7.9% local cattle and 4% yellow cattle but not in pigs. Results indicate that infection is most prevalent in goats.
Blastocystis sp. is a common enteric protozoan parasite found in humans and various type of animal worldwide. Recently, genotypic distribution of Blastocystis sp. was revealed in insects, rodents, avian and mammals, which exposed its potential of transmiting the infections to human. However, very little information on current level of Blastocystis sp. infection were reported in cattle from Malaysia. Herein, a total of 120 stool samples of cattles were collected. While the potential risk of infection such as age, gender, body score, diarrheic condition of the cattle were noted, the management of the farms was also recorded. All stool sample were cultured, but 80 samples were selected for PCR sequencing analysis. The cultivation and microscopic examination revealed only 25% of the cattle (30/120) were infected with Blastocystis sp.. But, 43.8% of the cattle (35/80) were found positive upon PCR sequencing. The study also found that age, body score condition, diarrheic condition and certain farm were associated with the infection (p<0.05). Six subtypes (STs) that were discovered during the study were ST10 (21.3%;17/35), ST5 (8.8%;7/35), ST3 (7.5%;6/35), ST1 (2.5%;2/35), ST4 (2.5%;2/35) and ST14 (1.3%;1/35). Thus, moderate infections of Blastocystis sp. and variants in the genotypic distributions of the cattle suggest its potential for zoonotic transmission. Therefore, this findings could be helpful for further understanding the parasite, which assist studies of its pathogenicity.
Blastocystis is the most frequently observed eukaryotic gastrointestinal symbiont in humans and animals. Its low host specificity and zoonotic potential suggest that animals might serve as possible reservoirs for transmission. The prevalence and subtype distributions of Blastocystis sp. in animal populations in Southeast Asia, a hotspot for zoonotic diseases, are reviewed. Recommendations for future research aimed at understanding the zoonotic role of Blastocystis are also included. Seven countries have, so far, reported Blastocystis infection in various animals, such as livestock, poultry, companion animals, and non-human primates. Pigs were the most studied animals, and there were records of 100% prevalence in pigs, cattle, and ostriches. Using polymerase chain reaction (PCR)-based approaches, twelve Blastocystis sp. subtypes (STs), namely ST1, ST2, ST3, ST4, ST5, ST6, ST7, ST8, ST9, ST10, ST12, and ST14 have been recognised infecting animals of Southeast Asia. ST1 and ST5 were the most frequently identified, and Malaysia observed the most diverse distribution of subtypes. Further investigations on Blastocystis sp. in various animal hosts, using adequate sample sizes and uniform detection methods, are essential for a better understanding of the distribution of this organism. Detailed genome studies, especially on STs shared by humans and animals, are also recommended.