Territorial and duet calls of three Malaysian owl species

Vocalisations of tropical birds are still largely unexplored particularly the nocturnal species. This study examined and quantitatively described the territorial calls and duets of the Sunda Scops-Owl (Otus lempiji), Brown Boobook (Ninox scutulata) and Spotted Wood-Owl (Strix seloputo) based on 105 territorial call and four duetting recordings collected from one forest reserve and oil palm smallholdings in Selangor, Peninsular Malaysia. Wilcoxon signed-rank tests found significant differences (p<0.05) for almost all vocal parameters measured from the spectrograms derived from the duets with one higher-pitched than the other. Being the first study to describe the vocal structure of the duetting calls of the three Malaysian strigids, this study serves as a baseline for future behavioural study of nocturnal birds particularly pertaining to conspecific interactions in the Sunda region

Genetic assemblage of Sarcocystis spp. in Malaysian snakes

Abstract Background: Sarcocystis species are protozoan parasites with a wide host range including snakes. Although there were several reports of Sarcocytis species in snakes, their distribution and prevalence are still not fully explored. Methods: In this study, fecal specimens of several snake species in Malaysia were examined for the presence of Sarcocystis by PCR of 18S rDNA sequence. Microscopy examination of the fecal specimens for sporocysts was not carried as it was difficult to determine the species of the infecting Sarcocystis. Results: Of the 28 snake fecal specimens, 7 were positive by PCR. BLASTn and phylogenetic analyses of the amplified 18S rDNA sequences revealed the snakes were infected with either S. nesbitti, S. singaporensis, S. zuoi or undefined Sarcocystis species. Conclusion: This study is the first to report Sarcocystis infection in a cobra, and S. nesbitti in a reticulated python

Specific, sensitive and rapid detection of human plasmodium knowlesi infection by loop-mediated isothermal amplification (LAMP) in blood samples

<p>Abstract</p> <p>Background</p> <p>The emergence of <it>Plasmodium knowlesi </it>in humans, which is in many cases misdiagnosed by microscopy as <it>Plasmodium malariae </it>due to the morphological similarity has contributed to the needs of detection and differentiation of malaria parasites. At present, nested PCR targeted on <it>Plasmodium </it>ssrRNA genes has been described as the most sensitive and specific method for Plasmodium detection. However, this method is costly and requires trained personnel for its implementation. Loop-mediated isothermal amplification (LAMP), a novel nucleic acid amplification method was developed for the clinical detection of <it>P. knowlesi</it>. The sensitivity and specificity of LAMP was evaluated in comparison to the results obtained via microscopic examination and nested PCR.</p> <p>Methods</p> <p>LAMP assay was developed based on <it>P. knowlesi </it>genetic material targeting the apical membrane antigen-1 (AMA-1) gene. The method uses six primers that recognize eight regions of the target DNA and it amplifies DNA within an hour under isothermal conditions (65°C) in a water-bath.</p> <p>Results</p> <p>LAMP is highly sensitive with the detection limit as low as ten copies for AMA-1. LAMP detected malaria parasites in all confirm cases (n = 13) of <it>P. knowlesi </it>infection (sensitivity, 100%) and none of the negative samples (specificity, 100%) within an hour. LAMP demonstrated higher sensitivity compared to nested PCR by successfully detecting a sample with very low parasitaemia (< 0.01%).</p> <p>Conclusion</p> <p>With continuous efforts in the optimization of this assay, LAMP may provide a simple and reliable test for detecting <it>P. knowlesi </it>malaria parasites in areas where malaria is prevalent.</p

ダイチョウキン ニ オケル ヒドロキシウレア ニ ヨル DNA ソンショウ ノ ユウドウ

博第1567号甲第1567号博士(バイオサイエンス)奈良先端科学技術大学院大

Vocal individuality of Sunda Scops-Owl (Otus lempiji) in Peninsular Malaysia

Like many owl species, Sunda Scops-Owls (Otus lempiji) are difficult to monitor using traditional survey techniques, because of their nocturnal habits, secretive nature, and cryptic coloration. Individual variation in vocalizations could potentially be used to distinguish individuals of this owl species, as has been demonstrated for many bird species. The objectives of this study were to describe the territorial call of Sunda Scops-Owls, to determine whether the calls can be distinguished individually, and to examine whether the calls from the same individuals were stable over time. We analyzed 75 recordings collected from 12 owls from December 2014 to June 2015 in a lowland forest and oil palm smallholdings in Selangor State, Peninsular Malaysia. Using two temporal parameters and six frequency parameters derived from spectrogram, we employed ANOVA tests and found significant differences for all parameters among individual owls. Discriminant function analysis correctly classified 97.1% of the owl calls to the correct individuals. Based on the Wilcoxon signed-rank test, all vocal parameters did not vary significantly for the six birds that were vocally active over two predetermined survey sessions within the breeding period. Our results demonstrated that Sunda Scops-Owls can be identified individually by their vocalizations. This implies that assessing vocal individuality can be useful as a noninvasive method for surveying the Sunda Scops-Owls and the method should be further tested for other little-known owl species in the tropics

Nutritional conditions and oxygen concentration affect spontaneous occurrence of homologous recombination events but not spontaneous mutagenesis in Escherichia coli

Effects of environmental factors for growth of Escherichia coli on spontaneous mutagenesis and homologous recombination events are described. By analyzing rifampicin-resistant (Rifr) mutation frequencies in an E. coli strain lacking MutM and MutY repair enzymes, which suppress base substitution mutations caused by 8-oxoguanine (7,8 dihydro-8-oxoguanine; 8-oxoG) in DNA, we examined levels of oxidative DNA damage produced in normally growing cells. The level of 8-oxoG DNA damage was about 9- and 63-fold higher in cells grown in M9-glucose and M9-glycerol media, respectively, than in those grown in LB medium. We also found that about 14-fold more 8-oxoG DNA damage was produced in cells grown in about 0.1% oxygen than in those grown in the normal atmosphere. However, Rifr mutation frequency in wild-type cells was unchanged in such different growth conditions, suggesting that the capacity of repair mechanisms is sufficient to suppress mutations caused by 8-oxoG even at very high levels in cells growing in the particular conditions. On the other hand, the frequency of spontaneous homologous recombination events in wild-type E. coli cells varied with different growth conditions. When cells were grown in M9-glucose and M9-glycerol media, the spontaneous recombination frequency increased to about 4.3- and 7.3-fold, respectively, higher than that in LB medium. Likewise, the spontaneous recombination frequency was about 3.5-fold higher in cells growing in the hypoxic condition than in cells growing in the atmosphere. When cells were grown in anaerobic conditions, the recombination frequency decreased to half of that in the atmosphere. These data indicated that spontaneous homologous recombination is highly responsive to environmental factors such as nutrition and oxygen concentration