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โครงการรวบรวมและจัดทําเอกสารวารสารอิเล็กทรอนิกส์ มหาวิทยาลัยเกษตรศาสตร์

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Peirce, 1989; Valkiunas, 2005). Many studies have shown the impact of blood parasites on the
reproductive system, e.g., delayed arrival to breeding grounds, decreased cluster size, reduced
hatching success and babies with poor body condition scores (Applegate, 1970; Merino et al., 2000;
Tomás et al., 2007; Knowles et al., 2009; Knowles et al., 2010; Dunn et al., 2013).
Plasmodium is generally considered to be more pathogenic than Haemoproteus and

Leucocytozoon. Several haemosporidian parasites have been reported in Strigiformes across the
world (Paperna et al., 2008). Nine morphologically distinct haemosporidian species have been
reported, including Plasmodium subpraecox, P. fallax, P. forresteri, P. gundersi, P. hexamerium, P.
elongatum, H. noctuae, H. syrnii and Leucocytozoon danilewskyi (Karadjian et al., 2014). Unidentified
plasmodium was found in several Strigidae due to low quality blood smears. Only P. elongatum can
be identified in the Barred owl (Strix varia). Due to lower virulence, few studies mention
Haemosporidian infection. H. noctuae was reported in the Brown Hawk-owl (Ninox scutulata) and H.
cf. noctuae was reported in the Collared owlet (Glaucidium brodiei). H. syrnii was reported in N.
scutulata and the Spotted wood owl (Strix seloputo). Unidentified haemosporidian was also reported

in Strigidae and Tytonidae. Recently, H. ilanpapernai was morphologically and molecularly
differentiated from H. syrnii in S. seloputo (Ishak et al., 2008).
Recently, the prevalence of blood parasite infections in barn owls was quite low (24%) in the
United States (Ishak et al., 2008). Previous studies also demonstrated no or low blood parasite
infection in barn owls, suggesting that habitats of barn owls in Denmark and northern European
countries might not be suitable for blood parasite vectors (Tella et al., 1999; Krone et al., 2001). In
Thailand, the barn owl plays an important role in the oil palm industry as a biological rodenticide.
In many oil palm plantations, breeding and health monitoring programs are established to maintain

the population of barn owls. However, there was no report about haemosporidian in barn owls in
Thailand among a low number of studies on this species.
Molecular techniques are considered to be powerful tools for identifying and characterizing
blood parasites. In this study, blood samples were collected from seventeen barn owls (Tyto alba)
in captivity at an oil palm plantation, Chumphon Province, in the southern part of Thailand. We
identified haemosporidian from blood samples by PCR techniques and sequencing.

MATERIALS AND METHODS

The EDTA blood samples collected from seventeen Barn owls (Tyto alba) in captivity at an oil
palm plantation, Chumphon Province, in the southern part of Thailand were sent for molecular
sexing by the local farmer. The blood samples were also subjected to DNA extraction by a modified
phenol-chloroform method (Nelson & Krawetz, 1992) for observation of blood parasites by PCR
technique.
The PCR product was amplified by two separate sets of primer. Firstly, the primers DW2 (5’-

TAATGCCTAGACGTATTCCTGATTATCCAG–3’) and DW4 (5’-TGTTTGCTTGGGAGCTGTAATCATAATGTG–
3’) were specific to the cytochrome b (Cytb) region of mitochondrial DNA (mtDNA) (Perkins & Schall,
2002). Secondly, the newly designed primers Haem311w (5’-GACGTTCTTAACCCAGCTCACG– 3’) and
Haem2020w (5’-CAGTCCCAGCGACAGCGGTTA– 3’) were specific to the cytochrome c oxidase subunit

วารสารสัตว์ป่าเมืองไทย ปีที่ 24 พ.ศ. 2560 Journal of Wildlife in Thailand Vol. 24, 2017