RESUMEN

Cytochrome oxidase subunit I (COI) gene has been recognized as an authentic tool for species identification. Besides its potential barcoding capacity, COI sequences have also been used for inferring the phylogeny. Phylogenetic relationships among genera of Columbidae (pigeons and doves family) have not been fully resolved because of scarce sampling of taxa and limited availability of sequence data. In this study, we have evaluated the efficiency of COI barcodes for species identification and phylogenetic analysis of various doves. We sequenced the 693 bp region of COI gene of three species of doves including Oena capensis, Streptopelia decaocto, and Streptopelia senegalensis. After retrieving the relevant sequences from the GenBank, the entire data-set of 85 sequences represented 25 dove species from 11 different genera of the family Columbidae. The COI sequences of four species including Chalcophaps indica (two specimens), Columbina inca (five specimens), Geopelia striata (three specimens), and Macropygia phasianella (three specimens) were identical. The mean intraspecific base differences ranged from 0 to 37 while the P-distances ranged between 0 and 0.058. For most of the species, the P-distances were ≤ 0.008. Phylogenetic analysis differentiated the taxa into three major clusters. One of the clusters grouped five genera including Claravis, Columbina, Gallicolumba, Geopelia, and Geotrygon. The remaining two clusters grouped three genera each including Chalcophaps, Oena, and Turtur in one cluster and Macropygia, Streptopelia, and Zenaida in another cluster. Further sub-clustering clearly separated all the genera into individual clusters except two discrepancies for the genera Streptopelia and Turtur. Species-level cladistics clearly separated all the species into distinctive clades. In conclusion, COI barcoding is a powerful tool for species identification with added information on phylogenetic inference. The finding of this study will help to understand the complex phylogeny of the family Columbidae.

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RESUMEN

Recently, DNA barcoding based on mitochondrial cytochrome c oxidase subunit I (COI) has gained wide attention because of simplicity and robustness of these barcodes for species identification including birds. The current GenBank records show the COI barcodes of only one species, chukar partridge (Alectoris chukar), of the Alectoris genus. In this study, we sequenced the 694 bp segment of COI gene of the two species including, Arabian partridge (Alectoris melanocephala) and Philby's rock partridge (Alectoris philbyi) of the same genus. We also compared these sequences with earlier published barcodes of chukar partridge. The pair-wise sequence comparison showed a total of 53 variable sites across all the 9 sequences from 3 species. Within-species variable sites were found to be 4 (Alectoris chukar), 0 (Alectoris philbyi) and 3 (Alectoris melanocephala). The genetic distances among the 9 individuals varied from 0.000 to 0.056. Phylogenetic analysis using COI barcodes clearly discriminated the 3 species, while Alectoris chukar was found to be more closely related to Alectoris philbyi. Similar differentiation was also observed using 1155 bp mitochondrial control region (CR) sequences suggesting the efficiency of COI gene for phylogenetic reconstruction and interspecific identification. This is the first study reporting the barcodes of Arabian partridge and Philby's rock partridge.

RESUMEN

This investigation was aimed to study the effects of individual and concomitant exposures of the two nitrile compounds, the industrially important acrylonitrile (ACN; 5, 15, 45 mg/kg/day) and the positive control iminodipropionitrile (IDPN; 100 mg/kg/day) in rats. The six treatment groups were 1 (control), 2 (ACN 5), 3 (ACN 15), 4 (ACN 45), 5 (IDPN), and 6 (IDPN + ACN 15). Both the drugs were started on the same day and continued for 9 days (IDPN was given daily 30 min before ACN but stopped a day earlier). The animals were daily observed for neurobehavioral abnormalities including dyskinetic head movements, circling, tail hanging, air righting reflex, and contact inhibition of righting reflex. There was no dyskinetic behavioral abnormality in the animals treated with any of the three doses of ACN whereas all the rats in IDPN alone treated group developed clear symptoms of excitation, circling, and chorea syndrome (ECC syndrome) on day 9. Concomitant treatment of rats with ACN significantly attenuated the severity of IDPN-induced behavioral deficits. Administration of ACN significantly depleted glutathione (GSH) in striatum, hippocampus and cerebral cortex; IDPN significantly reduced the GSH only in striatum. The anterior striatum showed intense tyrosine hydroxylase (TH) expression in IDPN alone treated rat as compared to control and ACN alone treated rat. Cotreatment with ACN reduced the intensity of TH immunostaining in IDPN-treated rats. Administration of IDPN alone caused massive loss of vestibular sensory hair cells in the crista ampullaris whereas the sensory epithelium appeared intact in ACN alone treated groups. The animals receiving the combination of ACN and IDPN showed comparatively less degeneration of sensory hair cells than IDPN alone group. These findings suggest that ACN and IDPN produce different behavioral effects that are exerted through entirely different mechanisms; the nervous and vestibular systems appear to be the major target sites of these toxins, respectively.

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