• Title/Summary/Keyword: Population conservation

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Insights into the genetic diversity of indigenous goats and their conservation priorities

  • Liu, Gang;Zhao, Qianjun;Lu, Jian;Sun, Feizhou;Han, Xu;Zhao, Junjin;Feng, Haiyong;Wang, Kejun;Liu, Chousheng
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.10
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    • pp.1501-1510
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    • 2019
  • Objective: An experiment was conducted to evaluate genetic diversity of 26 Chinese indigenous goats by 30 microsatellite markers, and then to define conservation priorities to set up the protection programs according to the weight given to within- and between-breed genetic diversity. Methods: Twenty-six representative populations of Chinese indigenous goats, 1,351 total, were sampled from different geographic regions of China. Within-breed genetic diversity and marker polymorphism were estimated calculating the mean number of alleles, observed heterozygosities, expected heterozygosities, fixation index, effective number of alleles and allelic richness. Conservation priorities were analyzed by statistical methods. Results: A relatively high level of genetic diversity was found in twenty-four population; the exceptions were in the Daiyun and Fuqing goat populations. Within-breed kinship coefficient matrices identified seven highly inbred breeds which should be of concern. Of these, six breeds receive a negative contribution to heterozygosity when the method was based on proportional contribution to heterozygosity. Based on Weitzman or Piyasatian and Kinghorn methods, the breeds distant from others i.e. Inner Mongolia Cashmere goat, Chengdu Brown goat and Leizhou goat obtain a high ranking. Evidence from Caballero and Toro and Fabuel et al method prioritized Jining Gray goat, Liaoning Cashmere goat, and Inner Mongolia Cashmere goat, which agree with results from Kinship-based methods. Conclusion: Conservation priorities were determined according to multiple methods. Our results suggest Inner Mongolia Cashmere goat (most methods), Jining Gray goat and Liaoning Cashmere goat (high contribution to heterozygosity and total diversity) should be prioritized based on most methods. Furthermore, Daiyun goat and Shannan White goat also should be prioritized based on consideration of effective population size. However, if one breed can continually survive under changing conditions, the straightforward approach would be to increase its utilization and attraction for production via mining breed germplasm characteristics.

Acoustic-based estimation of fish stocks in Widas Reservoir, East Java, Indonesia

  • Siti Nurul Aida;Agus Djoko Utomo;Safran Makmur;Tuah Nanda M. Wulandari;Khoirul Fatah;Yosmaniar;Indra Suharman;Ulung Jantama Wisha
    • Fisheries and Aquatic Sciences
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    • v.27 no.4
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    • pp.240-255
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    • 2024
  • Widas Reservoir is situated in an area of 570 ha in the Pajaran Village, Madiun Regency, East Java Province, Indonesia, playing an essential role in fisheries, with the average fish catch per year of about 283 tons/year. This study explores the standing stock, growth parameters, mortality, and exploitation rates of several dominant fishes in Widas Reservoir. This study was carried out from February to November 2019. Fish stocks were estimated using acoustic tools, fish catch records, and sizes collected by local enumerators. Fish length frequency sampling was conducted on several dominant fish species, such as Oreochromis niloticus, Barbonymus gonionotus, and Osteochilus vittatus. Based on the length-frequency data, estimating fish population dynamics, the fish population dynamics (infinitive length (L) and growth coefficient (K)) estimation was run in a time series using the Fish Sock Analysis Tool, II (FISAT II) program package. Moreover, the estimation of natural mortality parameters, the fishing mortality parameter, and the exploitation rate was also performed. The approximated overall fish stock in the Widas Reservoir was about 79,848 kg, which lowered with the increase in water depth. Of particular concern, in the surface layer at a depth between 1-5 m, the fish stock reached 58,813 kg, while in the deeper zone (> 15 m), the value significantly lowered by about 98%, reaching 1,219 kg. These results indicate an overfishing in the Widas Reservoir. The value of the exploitation rate (E) of B. gonionotus was 0.748, O. niloticus 0.8, and O. vittatus 0.7, respectively, proving the overfishing states occurred in the study area. Therefore, regulations governing the number of catches and the use of fishing gear are crucial in Widas Reservoir, particularly the use of lift and gill nets with a mesh size of less than 2 cm.

The Establishment of Conservation Area and Conservation Strategy in Ulnung Island(II) -Habitat Situation and Morphological Characteristics of Cotoneaster Wilsonii Nakai in Ulnung Island- (울릉도의 보전지역 설정 및 보전전략(II) -섬개야광나무 서식처현황 및 형태적 특성-)

  • 신현탁;김용식;유지현
    • Korean Journal of Environment and Ecology
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    • v.17 no.2
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    • pp.133-143
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    • 2003
  • The three wild populations including unrecorded two wild populations and Do-dong population, where designated as a Natural Monument NO 51, of Cotoneaster wilsonii in Ulnung Island were studied. The population at Yilmoldae, western coast of the island is in the threat by the visitors, while the population at Tonggumi is well conserved due to the geomorphologically difficult to access . The existing 25 to 50 maturing individuals are are potentially vital sources fer the island species recovery projects in the future. There are no statistical difference in the floral characteristics of the species such as both length and width of the petals, while statistical difference were shown from the leaf characteristics such as length, width and area of the leaves in the three studies areas.

Genetic Diversity of Indigenous Cattle Populations in Bhutan: Implications for Conservation

  • Dorji, T.;Hanotte, O.;Arbenz, M.;Rege, J.E.O.;Roder, W.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.7
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    • pp.946-951
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    • 2003
  • The Genetic diversity and relationship of native Siri (Bos indicus) cattle populations of Bhutan were evaluated using 20 microsatellite markers. A total of 120 Siri cattle were sampled and were grouped into four populations according to their geographical locations which were named Siri West, Siri South, Siri Central and Siri East cattle. For each, 30 individuals were sampled. In addition, 30 samples each of Indian Jaba (B. indicus), Tibetan Goleng (B. taurus), Nepal Hill cattle (B. indicus), Holstein Friesian (B.taurus) and Mithun (B. frontalis) were typed. The mean number of alleles per loci (MNA) and observed heterozygosity (Ho) were high in the Siri populations ($MNA=7.2{\pm}0.3$ to $8.9{\pm}0.5$ and $Ho=0.67{\pm}0.04$ to $0.73{\pm}0.03$). The smallest coefficient of genetic differentiation and genetic distance ($F_{ST}=0.015$ and $D_A=0.073$) were obtained between Siri West and Siri Central populations. Siri East population is genetically distinct from the other Siri populations being close to the Indian Jaba ($F_{ST}=0.024$ and $D_A=0.084$). A high bootstrap value of 96% supported the close relationship of Siri South, Siri Central and Siri West, while the relationship between Siri East and Jaba was also supported by a high bootstrap value (82%). Data from principal component analysis and individual assignment test were in concordance with the inference from genetic distance and differentiation. In conclusion we identified two separate Siri cattle populations in Bhutan at the genetic level. One population included Siri cattle sampled from the West, Central and South of the country and the other Siri cattle was sampled from the East of the country. We suggest that Siri cattle conservation program in Bhutan should focus on the former population as it has received less genetic influence from other cattle breeds.

Assessment of genetic diversity of Prangos fedtschenkoi (Apiaceae) and its conservation status based on ISSR markers

  • Mustafina, Feruza U.;Kim, Eun Hye;Son, Sung-Won;Turginov, Orzimat T.;Chang, Kae Sun;Choi, Kyung
    • Korean Journal of Plant Taxonomy
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    • v.47 no.1
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    • pp.11-22
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    • 2017
  • Prangos fedtschenkoi (Regel et Schmalh.) Korovin (Apiaceae) is an endemic species for mountainous Middle Asia, which is both a rare and useful plant. Organic extractions from this species are being used in pharmaceutics and cosmetology. In recent years, P. fedtschenkoi distribution area has considerably decreased, presumably, resulting from human activities such as agriculture, construction works, overgrazing and collection from wild for pharmaceutic purposes. Six populations were found in Uzbekistan and their genetic divergence and differentiation were studied with 10 inter-simple sequence repeat (ISSR) markers, selected out of 101. Totally 166 amplified ISSR fragments (loci) were revealed, of which 164 were polymorphic. Relatively moderate level of polymorphism was found at population level with polymorphic bands ranging from 27.71% to 47.59%. Mean P = 39.05%, $N_a=1.40$, $N_e=1.25$, S.I. = 0.21, and $H_e=0.14$ were revealed for all loci across six populations. AMOVA showed higher variation among populations (62%) than within them (38%). The Bayesian model determined 5 clusters, or genetic groups. The posteriori distribution of the Theta II estimator detected full model identifying high inbreeding, intensified by low gene flow (Nm = 0.3954). Mantel test confined population 6 as distinct cluster corresponding to geographic remoteness (R = 0.5137, $p{\leq}0.005$). Results were used as the bases for developing conserve measures to restore populations.

Genetic characterization and population structure of six brown layer pure lines using microsatellite markers

  • Karsli, Taki;Balcioglu, Murat Soner
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.1
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    • pp.49-57
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    • 2019
  • Objective: The first stage in both breeding and programs for the conservation of genetic resources are the identification of genetic diversity in the relevant population. The aim of the present study is to identify genetic diversity of six brown layer pure chicken lines (Rhode Island Red [RIRI, RIRII], Barred Rock [BARI, BARII], Columbian Rock [COL], and line 54 [L-54]) with microsatellite markers. Furthermore, the study aims to employ its findings to discuss the possibilities for the conservation and sustainable use of these lines that have been bred as closed populations for a long time. Methods: In the present study, a total number of 180 samples belonging to RIRI (n = 30), RIRII (n = 30), BARI (n = 30), BARII (n = 30), L-54 (n = 30), and COL (n = 30) lines were genotyped using 22 microsatellite loci. Microsatellite markers are extremely useful tools in the identification of genetic diversity since they are distributed throughout the eukaryotic genome in multitudes, demonstrate co-dominant inheritance and they feature a high rate of polymorphism and repeatability. Results: In this study, we found all loci to be polymorphic and identified the average number of alleles per locus to be in the range between 4.41 (BARI) and 5.45 (RIRI); the observed heterozygosity to be in the range between 0.31 (RIRII) and 0.50 (BARII); and $F_{IS}$ (inbreeding coefficient) values in the range between 0.16 (L-54) and 0.46 (RIRII). The $F_{IS}$ values obtained in this context points out to a deviation from Hardy-Weinberg equilibrium due to heterozygote deficiency in six different populations. The Neighbour-Joining tree, Factorial Correspondence Analysis and STRUCTURE clustering analyzes showed that six brown layer lines were separated according to their genetic origins. Conclusion: The results obtained from the study indicate a medium level of genetic diversity, high level inbreeding in chicken lines and high level genetic differentiation between chicken lines.

Distribution, Habitat Characteristics and Assessment of the Conservation Status of a Rare Mistletoe Species, Loranthus tanakae(Loranthaceae) in Korea (희귀식물 꼬리겨우살이의 분포와 생태적 특성 및 보전지위 평가)

  • Lee, Su Gwang;Chung, Jae Min;Kim, Sung Sik;Woo, Su Young;Kang, Ho Duck
    • Journal of Korean Society of Forest Science
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    • v.102 no.3
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    • pp.428-436
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    • 2013
  • To obtain biological basic data for the conservation strategies establishment of a rare mistletoe species, Loranthus tanakae(Loranthaceae) in Korea, the distribution range, habitat characteristics and an assessment of the conservation status on the natural populations of L. tanakae were investigated. As a result, the natural populations of L. tanakae were distributed in Bakdudaegan from Mt. Chiri to Mt Seorak in Korea penninsula, and 97.8% of surveyed individuals of the mistletoe species were found in Gangwon province. In natural populations, 1,385 individuals of L. tanakae were parasitic on 480 host trees, and distributed in sunshiny ridges of mountains of altitude range of 353 m to 1,250 m. The range of host trees of L. tanakae were composed of 5 families, 6 genera, 9 species, 1 subspecies, and of these, Quercus mongolica was preferred with 81.5% (389 trees among 480 host trees). As a result of assessing the conservation status through IUCN, L. tanakae was evaluated as Vulnerable (VU). It was considered that Mt. Seorak, Mt. Taegi and Mt. Odae population as habitats with the highest density of distribution of natural populations of L. tanakae should be designated as the protected areas. Thus, conservation strategies and related methods of the natural populations of L. tanakae were also discussed for the sustainable conservation.

Spatial Conservation Prioritization Considering Development Impacts and Habitat Suitability of Endangered Species (개발영향과 멸종위기종의 서식적합성을 고려한 보전 우선순위 선정)

  • Mo, Yongwon
    • Korean Journal of Environment and Ecology
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    • v.35 no.2
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    • pp.193-203
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    • 2021
  • As endangered species are gradually increasing due to land development by humans, it is essential to secure sufficient protected areas (PAs) proactively. Therefore, this study checked priority conservation areas to select candidate PAs when considering the impact of land development. We determined the conservation priorities by analyzing four scenarios based on existing conservation areas and reflecting the development impact using MARXAN, the decision-making support software for the conservation plan. The development impact was derived using the developed area ratio, population density, road network system, and traffic volume. The conservation areas of endangered species were derived using the data of the appearance points of birds, mammals, and herptiles from the 3rd National Ecosystem Survey. These two factors were used as input data to map conservation priority areas with the machine learning-based optimization methodology. The result identified many non-PAs areas that were expected to play an important role conserving endangered species. When considering the land development impact, it was found that the areas with priority for conservation were fragmented. Even when both the development impact and existing PAs were considered, the priority was higher in areas from the current PAs because many road developments had already been completed around the current PAs. Therefore, it is necessary to consider areas other than the current PAs to protect endangered species and seek alternative measures to fragmented conservation priority areas.

Assessment of population structure and genetic diversity of German Angora rabbit through pedigree analysis

  • Abdul Rahim;K. S. Rajaravindra;Om Hari Chaturvedi;S. R. Sharma
    • Animal Bioscience
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    • v.36 no.5
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    • pp.692-703
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    • 2023
  • Objective: The main goals of this investigation were to i) assess the population structure and genetic diversity and ii) determine the efficiency of the ongoing breeding program in a closed flock of Angora rabbits through pedigree analysis. Methods: The pedigree records of 6,145 animals, born between 1996 to 2020 at NTRS, ICAR-CSWRI, Garsa were analyzed using ENDOG version 4.8 software package. The genealogical information, genetic conservation index and parameters based on gene origin probabilities were estimated. Results: Analysis revealed that, 99.09% of the kits had both parents recorded in the whole dataset. The completeness levels for the whole pedigree were 99.12%, 97.12%, 90.66%, 82.49%, and 74.11% for the 1st, 2nd, 3rd, 4th, and 5th generations, respectively, reflecting well-maintained pedigree records. The maximum inbreeding, average inbreeding and relatedness were 36.96%, 8.07%, and 15.82%, respectively. The mean maximum, mean equivalent and mean completed generations were 10.28, 7.91, and 5.51 with 0.85%, 1.19%, and 1.85% increase in inbreeding, respectively. The effective population size estimated from maximum, equivalent and complete generations were 58.50, 27.05, and 42.08, respectively. Only 1.51% of total mating was highly inbred. The effective population size computed via the individual increase in inbreeding was 42.83. The effective numbers of founders (fe), ancestors (fa), founder genomes (fg) and non-founder genomes (fng) were 18, 16, 6.22, and 9.50, respectively. The fe/fa ratio was 1.12, indicating occasional bottlenecks had occurred in the population. The six most influential ancestors explained 50% of genes contributed to the gene pool. The average generation interval was 1.51 years and was longer for the sire-offspring pathway. The population lost 8% genetic diversity over time, however, considerable genetic variability still existed in the closed Angora population. Conclusion: This study provides important and practical insights to manage and maintain the genetic variability within the individual flock and the entire population.

Using High Resolution Ecological Niche Models to Assess the Conservation Status of Dipterocarpus lamellatus and Dipterocarpus ochraceus in Sabah, Malaysia

  • Maycock, Colin R.;Khoo, Eyen;Kettle, Chris J.;Pereira, Joan T.;Sugau, John B.;Nilus, Reuben;Jumian, Jeisin;Burslem, David F.R.P.
    • Journal of Forest and Environmental Science
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    • v.28 no.3
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    • pp.158-169
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    • 2012
  • Sabah has experienced a rapid decline in the extent of forest cover. The precise impact of habitat loss on the conservation status of the plants of Sabah is uncertain. In this study we use the niche modelling algorithm MAXENT to construct preliminary, revised and final ecological niche models for Dipterocarpus lamellatus and Dipterocarpus ochraceus and combined these models with data on current land-use to derive conservation assessments for each species. Preliminary models were based on herbarium data alone. Ground surveys were conducted to evaluate the performance of these preliminary models, and a revised niche model was generated from the combined herbarium and ground survey data. The final model was obtained by constraining the predictions of the revised models by filters. The range overlap between the preliminary and revised models was 0.47 for D. lamellatus and 0.39 for D. ochraceus, suggesting poor agreement between them. There was substantial variation in estimates of habitat loss for D. ochraceus, among the preliminary, revised and constrained models, and this has the potential to lead to incorrect threat assessments. From these estimates of habitat loss, the historic distribution and estimates of population size we determine that both species should be classified as Critically Endangered under IUCN Red List guidelines. Our results suggest that ground-truthing of ecological niche models is essential, especially if the models are being used for conservation decision making.