Monthly Archives - October 2016

Distribution and prevalence of malaria parasites among long-tailed macaques (Macaca fascicularis) in regional populations across Southeast Asia

Abstract

Background: Plasmodium knowlesi and Plasmodium cynomolgi are two malaria parasites naturally transmissible between humans and wild macaque through mosquito vectors, while Plasmodium inui can be experimentally trans‐ mitted from macaques to humans. One of their major natural hosts, the long-tailed macaque (Macaca fascicularis), is host to two other species of Plasmodium (Plasmodium fieldi and Plasmodium coatneyi) and is widely distributed in Southeast Asia. This study aims to determine the distribution of wild macaques infected with malarial parasites by examining samples derived from seven populations in five countries across Southeast Asia. Methods: Plasmodium knowlesi, P. cynomolgi, P. coatneyi, P. inui and P. fieldi, were detected using nested PCR assays in DNA samples from 276 wild-caught long-tailed macaques. These samples had been derived from macaques captured at seven locations, two each in the Philippines (n = 68) and Indonesia (n = 70), and one each in Cambodia (n = 54), Singapore (n = 40) and Laos (n = 44). The results were compared with previous studies of malaria parasites in long- tailed macaques from other locations in Southeast Asia. Fisher exact test and Chi square test were used to examine the geographic bias of the distribution of Plasmodium species in the  macaque populations.

Results: Out of 276 samples tested, 177 were Plasmodium-positive, with P. cynomolgi being the most common and widely distributed among all long-tailed macaque populations (53.3 %) and occurring in all populations examined, followed by P. coatneyi (20.4 %), P. inui (12.3 %), P. fieldi (3.4 %) and P. knowlesi (0.4 %). One P. knowlesi infection was detected in a macaque from Laos, representing the first documented case of P. knowlesi in wildlife in Laos. Chi square test showed three of the five parasites (P. knowlesi, P. coatneyi, P. cynomolgi) with significant bias in prevalence towards macaques from Malaysian Borneo, Cambodia, and Southern Sumatra, respectively.

Conclusions: The prevalence of malaria parasites, including those that are transmissible to humans, varied among all sampled regional populations of long-tailed macaques in Southeast Asia. The new discovery of P. knowlesi infection in Laos, and the high prevalence of P. cynomolgi infections in wild macaques in general, indicate the strong need of public advocacy in related countries.

Keywords: Plasmodium knowlesi, Plasmodium cynomolgi, Macaca fascicularis, Geographic distribution, Biased infection rate

Read full article here: 2016_malaria-article

Authors “Xinjun Zhang1 , Khamisah Abdul Kadir2 , Leslie Fabiola Quintanilla‑Zariñan1 , Jason Villano3 , Paul Houghton4 , Hongli Du5 , Balbir Singh2* and David Glenn Smith1*”

Genetic Testing for Non-human Primates

The Kanthaswamy DNA Laboratory (KDL) at Arizona State University in collaboration with Primate Products, Inc. (PPI) is pleased to announce our new Genetic Testing Program. Working with state of the art technology, including Next Generation Sequencing platforms, the following genetic testing services are now currently being offered:

ABO Blood Phenotyping

Knowledge of the ABO blood type is used for metabolism studies and stem cell research as well as for recipient matching in blood transfusion and tissue/organ transplantation studies.

Kinship

Primate breeders today have a limited male to female ratio. Juvenile growing groups are usually formed from related cohorts. Including related animals in a trial can bias the study’s results. This test estimates the relatedness/kinship between any one animal and any number of other animals. This is particularly of interest for multiple or specific import groups coming from one breeder. This test compares any single animal to all other animals in an import group multiple import groups of animals up to first cousin, or 1/8 relatedness.

Regional Origin and Ancestry

Animals of different ancestry and geographic regions can have genetic differences. These differences can cause varying responses to experimental factors and can confound study results. This test determines the geographic origin of the animals in question.

Hybridization

Animals may have admixed ancestry because they were derived from hybrid zones. For example, rhesus (Macaca mulatta) and cynomogus macaques (M. fascicularis) individuals originating from Indochina may exhibit varying degrees of rhesus and cynomolgus heritage because of hybridization between these species. Our test estimates the percentage of genome that is attributable to each species.