Genetic variability in three Amazon parrot species

Parrots of the genus Amazona are among the most threatened species of the Order Pscittaciformes. This work describes allozyme polymorphisms in three Amazon parrot species - the Blue-fronted Amazon (Amazona aestiva), the Orange-winged Amazon (Amazona amazonica), and the Festive Amazon (Amazona festiva) -, and provides useful data for the evaluation of their genetic variability. We electrophoretically analyzed blood samples from 68 wild-caught individuals, maintained in captivity in three Brazilian zoos. Eight of the ten studied enzyme loci exhibited polymorphism. Glucosephosphate isomerase (Gpi) proved to be a diagnostic locus for the identification of these Amazon species. The expected average heterozygosity of the Blue-fronted Amazon (0.060) differed significantly from the expected heterozygosities of the Orange-winged Amazon and the Festive Amazon (0.040 and 0.039, respectively). This result was discussed as a consequence of hybridization between two geographic A. aestiva subspecies, and alternatively as a particular trait of this species. Genetic variability of the Blue-fronted Amazon compared to birds in general is not low on a species-wide level, despite the fact that this parrot is one of the most illegally traded species. Allozyme analysis proved to be an useful tool in monitoring the genetic variation within the genus Amazona and can be applied in the management program of other threatened species of this genus.

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Mating System and Hybridity in Eucalyptus pauciflora

Australian Journal of Biological Sciences ◽

10.1071/bi9770337 ◽

1977 ◽

Vol 30 (4) ◽

pp. 337 ◽

Cited By ~ 49

Author(s):

MA Phillips ◽

AHD Brown

Keyword(s):

Mating System ◽

Outcrossing Rate ◽

Seedling Stage ◽

Average Heterozygosity ◽

Evolutionary Advantage ◽

Allozyme Polymorphisms ◽

Self Fertilization

Allozyme polymorphisms at four loci expressed in seeds, and three other loci expressed in seedlings, were used to determine the outcrossing rate in three natural subalpine populations of snow gum (E. paucijlora). Based on the seed loci data, an estimated 37 % of seed was derived from self-fertilization and 63 % from random outcrossing. In the most elevated population the estimate after germination was similar. However, at lower elevations the frequency of effective self-fertilization estimated at the seedling stage was only 16 %. The less elevated populations also showed a greater average heterozygosity and a larger increase in heterozygosity in the adult over the progeny stages. Heterosis apparently operated differentially in these populations-it was more intense at the lower altitudes. Selection in favour of outcrossed individuals may be an important factor in checking the spread through the population of genes which promote self-fertilization, and which would otherwise enjoy an evolutionary advantage.

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Genetic variability in the brazilian criollo horse breed

Ciência Rural ◽

10.1590/s0103-84782003000100022 ◽

2003 ◽

Vol 33 (1) ◽

pp. 137-142 ◽

Cited By ~ 1

Author(s):

Myriam Elizabeth Vinocur ◽

Karin Erica Brass ◽

Mara Iolanda Batistella Rubin ◽

Carlos Antonio Mondino Silva

Keyword(s):

Genetic Variability ◽

Rio Grande ◽

Blood Groups ◽

Rio Grande Do Sul ◽

Average Heterozygosity ◽

Horse Breed ◽

Allelic Frequencies ◽

Blood Types ◽

Inbreeding Level

Allelic frequencies of 7 blood groups and 8 protein systems were determined in 6 herds of Criollo horse breed raised in Rio Grande do Sul, Brazil. Analysis of these frequencies showed a significant isolation component (Fst = 0.0866; p<0.01) and construction of dendogram using Nei´s D confirmed this difference among the 6 herds. The highest values measuring genetic variability on 15 blood types were average heterozygosity: 0.4631; total number of alleles: 87 and probability of exclusion: 98%. When all herds were considered together, the inbreeding level (Fis) was zero. These results indicate that the Criollo horses have a large genetic variability.

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High Levels of Genetic Variability in an Isolated Colony of Rock-wallabies (Petrogale assimilis): Evidence from Three Classes of Molecular Markers

Australian Journal of Zoology ◽

10.1071/zo96058 ◽

1997 ◽

Vol 45 (2) ◽

pp. 199 ◽

Cited By ~ 12

Author(s):

Peter B. S. Spencer ◽

Mark Adams ◽

Helene Marsh ◽

David J. Miller ◽

Mark D. B. Eldridge

Keyword(s):

Genetic Variation ◽

Molecular Markers ◽

Genetic Variability ◽

Mating Systems ◽

Selective Pressure ◽

Multiple Mating ◽

Dna Fingerprints ◽

Average Heterozygosity ◽

Low Levels ◽

High Level

Estimates of genetic variation for a small (Ne = 39) colony of allied rock-wallabies (Petrogale assimilis) were calculated with three different categories of molecular marker. Average heterozygosity was estimated at 3·8% for allozymes, 47·3% for multilocus ‘DNA fingerprints’ and 85·5% for microsatellite markers. Overall these values indicate that this small isolated colony of rock-wallabies maintains a high level of genetic variation despite its relative isolation and the apparently low levels of migration between colonies. It is likely that mechanisms exist (such as kin avoidance, multiple mating systems, high and variable selective pressure in extreme and fluctuating environmental conditions) that promote the maintenance of high levels of genetic variation in isolated colonies of P. assimilis. These mechanisms are discussed in the context of the results obtained from the molecular markers.

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Being Attractive Brings Advantages: The Case of Parrot Species in Captivity

PLoS ONE ◽

10.1371/journal.pone.0012568 ◽

2010 ◽

Vol 5 (9) ◽

pp. e12568 ◽

Cited By ~ 43

Author(s):

Daniel Frynta ◽

Silvie Lišková ◽

Sebastian Bültmann ◽

Hynek Burda

Keyword(s):

In Captivity ◽

Parrot Species

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A COMPUTER MODEL ALLOWING MAINTENANCE OF LARGE AMOUNTS OF GENETIC VARIABILITY IN MENDELIAN POPULATIONS. II. THE BALANCE OF FORCES BETWEEN LINKAGE AND RANDOM ASSORTMENT

Genetics ◽

10.1093/genetics/82.2.377 ◽

1976 ◽

Vol 82 (2) ◽

pp. 377-399

Author(s):

Christopher Wills ◽

Charles Miller

Keyword(s):

Linkage Disequilibrium ◽

Genetic Variability ◽

Natural Populations ◽

Bimodal Distribution ◽

Average Heterozygosity ◽

Epistatic Interactions ◽

Selective Sampling ◽

Two Factors ◽

Random Assortment ◽

Balance Of Forces

ABSTRACT It is shown, through theory and computer simulations of outbreeding Mendelian populations, that there may be conditions under which a balance is struck between two factors. The first is the advantage of random assortment, which will, when multilocus selection is for intermediate equilibrium values, lead to higher average heterozygosity than when linkage is introduced. There is some indication that random assortment is also advantageous when selection is toward a uniform distribution of equilibrium values. The second factor is the advantage of linkage between loci having positive epistatic interactions. When multilocus selection is for a bimodal distribution of equilibrium values, an early advantage of random assortment is replaced by a later disadvantage. Linkage disequilibrium, which in finite populations is increased only by random or selective sampling, may hinder the movement of alleles to their selective equilibria, thus leading to the advantage of random assortment.—Some consequences of this approach to the structure of natural populations are discussed.

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Temperament in Captivity, Environmental Enrichment, Flight Ability, and Response to Humans in an Endangered Parrot Species

Journal of Applied Animal Welfare Science ◽

10.1080/10888705.2020.1765367 ◽

2020 ◽

pp. 1-13

Author(s):

Gabriela de A. P. Ramos ◽

Cristiano S. de Azevedo ◽

Talys H. A. Jardim ◽

Aline C. Sant’Anna

Keyword(s):

Environmental Enrichment ◽

Flight Ability ◽

In Captivity ◽

Parrot Species

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Bilateral Intratesticular Spermatoceles in a Critically Endangered Dama Gazelle (Nanger dama mhorr)

Case Reports in Veterinary Medicine ◽

10.1155/2020/8810770 ◽

2020 ◽

Vol 2020 ◽

pp. 1-3

Author(s):

Riley E. Thompson ◽

Holly J. Haefele ◽

Daniel P. O’Neil ◽

Budhan S. Pukazhenthi

Keyword(s):

Adult Male ◽

Threatened Species ◽

Wild Population ◽

Iucn Red List ◽

Red List ◽

Critically Endangered ◽

Normal Sperm ◽

The Us ◽

In Captivity

Dama gazelles (Nanger dama mhorr) are considered critically endangered by the IUCN Red List of Threatened Species since the wild population is comprised of fewer than 200 animals. Several zoos in Europe and some private ranches in the US (Texas) maintain this species in captivity as a hedge against extinction. A routine reproductive exam on an adult male revealed bilateral cysts in the testicular parenchyma. The fluid in the cysts contained copious, moderately progressive motile spermatozoa. Following examination, the gazelle was diagnosed with bilateral intratesticular spermatoceles. Electroejaculation yielded 1.5 ml of semen containing 387×106 total sperm with 50% motility and 45% morphologically normal sperm. The spermatoceles did not appear to cause pain or dysfunction, so no treatment was performed at this time. Since fewer than 10 animals are managed in captivity in the US, no intervention (castration/hemicastration) was considered.

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High Prevalence of Novel Beak and Feather Disease Virus in Sympatric Invasive Parakeets Introduced to Spain From Asia and South America

Diversity ◽

10.3390/d12050192 ◽

2020 ◽

Vol 12 (5) ◽

pp. 192

Author(s):

Francisco Morinha ◽

Martina Carrete ◽

José L. Tella ◽

Guillermo Blanco

Keyword(s):

Disease Virus ◽

Wild Populations ◽

Disease Symptoms ◽

Myiopsitta Monachus ◽

Psittacula Krameri ◽

Captive Populations ◽

High Prevalence ◽

In Captivity ◽

Parrot Species ◽

Feather Disease Virus

The psittacine beak and feather disease (PBFD) is a globally widespread infectious bird disease that mainly affects species within the Order Psittaciformes (parrots and allies). The disease is caused by an avian circovirus (the beak and feather disease virus, BFDV), which is highly infectious and can lead to severe consequences in wild and captive populations during an outbreak. Both legal and illegal trading have spread the BFDV around the world, although little is known about its prevalence in invasive parrot populations. Here, we analyze the BFDV prevalence in sympatric invasive populations of rose-ringed (Psittacula krameri) and monk parakeets (Myiopsitta monachus) in Southern Spain. We PCR-screened 110 blood samples (55 individuals from each species) for BFDV and characterized the genotypes of five positives from each species. About 33% of rose-ringed parakeets and 37% of monk parakeets sampled were positive for BFDV, while neither species showed disease symptoms. The circovirus identified is a novel BFDV genotype common to both species, similar to the BFDV genotypes detected in several parrot species kept in captivity in Saudi Arabia, South Africa and China. Our data evidences the importance of an accurate evaluation of avian diseases in wild populations, since invasive parrots may be bringing BFDV without showing any visually detectable clinical sign. Further research on the BFDV prevalence and transmission (individual–individual, captive–wild and wild–captive) in different bird orders and countries is crucial to understand the dynamics of the viral infection and minimize its impact in captive and wild populations.

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