ABSTRACT
BACKGROUND: Hyacinth macaw Anodorhynchus hyacinthinus is the largest parrot of the world and is considered vulnerable to extinction due to its habitat loss and illegal trade associated to the international pet market demand. Genetic studies on this species are still incipient to generate a consistent characterization of the population dynamics and to develop appropriate conservation strategies. In this sense, microsatellite markers may support the detection of a population genetic structure for this bird species. However, at this time, none Hyacinth macaw species-specific primers for microsatellite loci have been so far established. This study aimed to develop and characterize polymorphic microsatellite markers for A. hyacinthinus and to check for their cross-amplification in other parrot species. FINDINGS: Sequences containing repeated dinucleotide motifs were prospected and optimized from a genomic library that was enriched for microsatellites using magnetic beads. The analyses of 43-57 samples from wild individuals of three distinct Brazilian subpopulations led to the characterization of five polymorphic microsatellite loci. Allele richness per locus ranged from two to 12. Three loci exhibited observed heterozygosity values higher than 50%, but the overall average value among all loci was close to 45%. In addition, successful primer cross-amplification was verified in seven other investigated species of Neotropical parrots. CONCLUSIONS: The newly developed markers have shown to be potentially useful for in situ and ex situ population studies to support future conservation actions of Hyacinth macaw and other parrots.
Subject(s)
Gene Amplification/genetics , Microsatellite Repeats/genetics , Parrots/genetics , Animals , Animals, Wild , Brazil , Conservation of Natural Resources , Molecular Sequence DataABSTRACT
Understanding the intraspecific genetic composition of populations in different geographic locations is important for the conservation of species. If genetic variability is structured, conservation strategies should seek to preserve the diversity of units. Also, origin of individuals can be determined, which is important for guiding actions against animal trafficking. The hyacinth macaw (Anodorhynchus hyacinthinus) is located in allopatric regions, vulnerable to extinction and suffering animal trafficking pressure. Therefore, we characterized its population genetic structure based on 10 microsatellites from 98 individuals and 2123bp of mitochondrial sequence (ND5, cytochrome b, and ND2) from 80 individuals. Moderate to high levels of differentiation were observed among 3 geographic regions of Brazil: the north/northeast of the country, the north Pantanal, and the south Pantanal. Differentiation between the 2 regions within the Pantanal was not expected, as they are relatively close and there is no known barrier to macaw movement between these regions. These genetically differentiated groups were estimated to have diverged 16000 to 42000 years ago. The low genetic variability observed seems not to be the result of past bottlenecks, although a star-shaped haplotype network and the mismatch distribution suggest that there was recent demographic expansion in the north and northeast. Environmental changes in the Holocene could have caused this expansion. Given the genetic structure observed, the most probable regions of origin of 24 confiscated individuals were identified. Thus, these data helped to trace illegal traffic routes and identify natural populations that are being illegally harvested.
Subject(s)
Genetics, Population , Parrots/genetics , Animals , Animals, Wild , Bayes Theorem , Brazil , Conservation of Natural Resources , Crime , DNA, Mitochondrial/genetics , Genetic Variation , Geography , Haplotypes , Microsatellite Repeats , Sequence Analysis, DNAABSTRACT
Molted feather sampling is a useful tool for genetic analyses of endangered species, but it is often very laborious due to the low quality and quantity of the DNA obtained. In the present study we show the parts of feathers that resulted in better yield of DNA. In descending order these were: blood clot outside the umbilicus, umbilicus (without blood clot), tip, inner membrane, and small calamus. Compared to DNA extracted from blood samples, DNA extracted from feathers produced microsatellite alleles of poorer quality and had to be processed immediately after extraction. As expected due to the level of DNA degradation, molecular sexing protocols that result in shorter PCR products were more efficient.
ABSTRACT
Cross-amplification was tested and variability in microsatellite primers (designed for Neotropical parrots) compared, in five macaw species, viz., three endangered blue macaws (Cyanopsitta spixii [extinct in the wild], Anodorhynchus leari [endangered] and Anodorhynchus hyacinthinus [vulnerable]), and two unthreatened red macaws (Ara chloropterus and Ara macao). Among the primers tested, 84.6% successfully amplified products in C. spixii, 83.3% in A. leari, 76.4% in A. hyacinthinus, 78.6% in A. chloropterus and 71.4% in A. macao. The mean expected heterozygosity estimated for each species, and based on loci analyzed in all the five, ranged from 0.33 (A. hyacinthinus) to 0.85 (A. macao). As expected, the results revealed lower levels of genetic variability in threatened macaw species than in unthreatened. The low combined probability of genetic identity and the moderate to high potential for paternity exclusion, indicate the utility of the microsatellite loci set selected for each macaw species in kinship and population studies, thus constituting an aid in planning in-situ and ex-situ conservation.
ABSTRACT
Cross-amplification was tested and variability in microsatellite primers (designed for Neotropical parrots) compared, in five macaw species, viz., three endangered blue macaws (Cyanopsitta spixii [extinct in the wild], Anodorhynchus leari [endangered] and Anodorhynchus hyacinthinus [vulnerable]), and two unthreatened red macaws (Ara chloropterus and Ara macao). Among the primers tested, 84.6 percent successfully amplified products in C. spixii, 83.3 percent in A. leari, 76.4 percent in A. hyacinthinus, 78.6 percent in A. chloropterus and 71.4 percent in A. macao. The mean expected heterozygosity estimated for each species, and based on loci analyzed in all the five, ranged from 0.33 (A. hyacinthinus) to 0.85 (A. macao). As expected, the results revealed lower levels of genetic variability in threatened macaw species than in unthreatened. The low combined probability of genetic identity and the moderate to high potential for paternity exclusion, indicate the utility of the microsatellite loci set selected for each macaw species in kinship and population studies, thus constituting an aid in planning in-situ and ex-situ conservation.
ABSTRACT
An alpha actin gene segment, isolated from Nile tilapia (Oreochromis niloticus), was characterized by nucleotide sequencing, predicted amino acid sequence and Southern blot hybridization. Genomic DNA amplification resulted in a 1063-bp fragment corresponding to a partial alpha-cardiac muscle actin gene containing exons 3 to 6. Southern blot analysis of the restriction-digested DNA revealed that the Nile tilapia genome contains multiple muscle actin isoforms. Although comparison of the nucleotide sequence, amino acid residues and exon-intron organization of the isolated actin gene with those of other vertebrates showed a high level of identity, diagnostic amino acid residues can still be correlated to distinct actin genes in fish species.
