Sample records for cooperatively breeding cichlid
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The evolution of cooperative breeding in the African cichlid fish, Neolamprologus pulcher.
Wong, Marian; Balshine, Sigal
2011-05-01
The conundrum of why subordinate individuals assist dominants at the expense of their own direct reproduction has received much theoretical and empirical attention over the last 50 years. During this time, birds and mammals have taken centre stage as model vertebrate systems for exploring why helpers help. However, fish have great potential for enhancing our understanding of the generality and adaptiveness of helping behaviour because of the ease with which they can be experimentally manipulated under controlled laboratory and field conditions. In particular, the freshwater African cichlid, Neolamprologus pulcher, has emerged as a promising model species for investigating the evolution of cooperative breeding, with 64 papers published on this species over the past 27 years. Here we clarify current knowledge pertaining to the costs and benefits of helping in N. pulcher by critically assessing the existing empirical evidence. We then provide a comprehensive examination of the evidence pertaining to four key hypotheses for why helpers might help: (1) kin selection; (2) pay-to-stay; (3) signals of prestige; and (4) group augmentation. For each hypothesis, we outline the underlying theory, address the appropriateness of N. pulcher as a model species and describe the key predictions and associated empirical tests. For N. pulcher, we demonstrate that the kin selection and group augmentation hypotheses have received partial support. One of the key predictions of the pay-to-stay hypothesis has failed to receive any support despite numerous laboratory and field studies; thus as it stands, the evidence for this hypothesis is weak. There have been no empirical investigations addressing the key predictions of the signals of prestige hypothesis. By outlining the key predictions of the various hypotheses, and highlighting how many of these remain to be tested explicitly, our review can be regarded as a roadmap in which potential paths for future empirical research into the
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Paternity of subordinates raises cooperative effort in cichlids.
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Rick Bruintjes
Full Text Available In cooperative breeders, subordinates generally help a dominant breeding pair to raise offspring. Parentage studies have shown that in several species subordinates can participate in reproduction. This suggests an important role of direct fitness benefits for cooperation, particularly where groups contain unrelated subordinates. In this situation parentage should influence levels of cooperation. Here we combine parentage analyses and detailed behavioural observations in the field to study whether in the highly social cichlid Neolamprologus pulcher subordinates participate in reproduction and if so, whether and how this affects their cooperative care, controlling for the effect of kinship.We show that: (i male subordinates gained paternity in 27.8% of all clutches and (ii if they participated in reproduction, they sired on average 11.8% of young. Subordinate males sharing in reproduction showed more defence against experimentally presented egg predators compared to subordinates not participating in reproduction, and they tended to stay closer to the breeding shelter. No effects of relatedness between subordinates and dominants (to mid-parent, dominant female or dominant male were detected on parentage and on helping behaviour.This is the first evidence in a cooperatively breeding fish species that the helping effort of male subordinates may depend on obtained paternity, which stresses the need to consider direct fitness benefits in evolutionary studies of helping behaviour.
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Blanc Michel
2007-01-01
Full Text Available Abstract Background The tribe Lamprologini is the major substrate breeding lineage of Lake Tanganyika's cichlid species flock. Among several different life history strategies found in lamprologines, the adaptation to live and breed in empty gastropod shells is probably the most peculiar. Although shell-breeding arose several times in the evolutionary history of the lamprologines, all obligatory and most facultative shell-breeders belong to the so called "ossified group", a monophyletic lineage within the lamprologine cichlids. Since their distinctive life style enables these species to live and breed in closest vicinity, we hypothesized that these cichlids might be particularly prone to accidental hybridization, and that introgression might have affected the evolutionary history of this cichlid lineage. Results Our analyses revealed discrepancies between phylogenetic hypotheses based on mitochondrial and nuclear (AFLP data. While the nuclear phylogeny was congruent with morphological, behavioral and ecological characteristics, several species – usually highly specialized shell-breeders – were placed at contradicting positions in the mitochondrial phylogeny. The discordant phylogenies strongly suggest repeated incidents of introgressive hybridization between several distantly related shell-breeding species, which reticulated the phylogeny of this group of cichlids. Long interior branches and high bootstrap support for many interior nodes in the mitochondrial phylogeny argue against a major effect of ancient incomplete lineage sorting on the phylogenetic reconstruction. Moreover, we provide morphological and genetic (mtDNA and microsatellites evidence for ongoing hybridization among distantly related shell-breeders. In these cases, the territorial males of the inferred paternal species are too large to enter the shells of their mate, such that they have to release their sperm over the entrance of the shell to fertilize the eggs. With sperm
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What drives cooperative breeding?
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Walter D Koenig
2017-06-01
Full Text Available Cooperative breeding, in which more than a pair of conspecifics cooperate to raise young at a single nest or brood, is widespread among vertebrates but highly variable in its geographic distribution. Particularly vexing has been identifying the ecological correlates of this phenomenon, which has been suggested to be favored in populations inhabiting both relatively stable, productive environments and in populations living under highly variable and unpredictable conditions. Griesser et al. provide a novel approach to this problem, performing a phylogenetic analysis indicating that family living is an intermediate step between nonsocial and cooperative breeding birds. They then examine the ecological and climatic conditions associated with these different social systems, concluding that cooperative breeding emerges when family living is favored in highly productive environments, followed secondarily by selection for cooperative breeding when environmental conditions deteriorate and within-year variability increases. Combined with recent work addressing the fitness consequences of cooperative breeding, Griesser et al.'s contribution stands to move the field forward by demonstrating that the evolution of complex adaptations such as cooperative breeding may only be understood when each of the steps leading to it are identified and carefully integrated.
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Predation risk drives social complexity in cooperative breeders
Groenewoud, Frank; Frommen, Joachim Gerhard; Josi, Dario; Tanaka, Hirokazu; Jungwirth, Arne; Taborsky, Michael
2016-01-01
Predation risk is a major ecological factor selecting for group living. It is largely ignored, however, as an evolutionary driver of social complexity and cooperative breeding, which is attributed mainly to a combination of habitat saturation and enhanced relatedness levels. Social cichlids neither
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Sturmbauer, Christian; Salzburger, Walter; Duftner, Nina; Schelly, Robert; Koblmueller, Stephan
2010-01-01
Lake Tanganyika comprises a cichlid species flock with substrate-breeding and mouthbrooding lineages. While sexual selection via mate choice on male mating color is thought to boost speciation rates in mouthbrooding cichlids, this is not the case in substrate-breeding lamprologines, which mostly form stable pairs and lack sexual dichromatism. We present a comprehensive reconstruction of the evolution of the cichlid tribe Lamprologini, based upon mtDNA sequences and multilocus nuclear DNA (AFL...
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Evolutionary history of Lake Tanganyika's scale-eating cichlid fishes.
Koblmüller, Stephan; Egger, Bernd; Sturmbauer, Christian; Sefc, Kristina M
2007-09-01
Although Lake Tanganyika is not the most species-rich of the Great East African Lakes it comprises by far the greatest diversity of cichlid fishes in terms of morphology, ecology, and breeding styles. Our study focuses on the Tanganyikan cichlid tribe Perissodini, which exhibits one of the most peculiar feeding strategies found in cichlids-scale-eating. Their evolutionary history was reconstructed from 1416 bp DNA sequence of two mitochondrial genes (ND2 and partial control region) and from 612 AFLP markers. We confirm the inclusion of the zooplanktivorous genus Haplotaxodon in the tribe Perissodini, and species status of Haplotaxodon trifasciatus. Within the Perissodini, the major lineages emerged within a short period roughly 1.5-2 MYA, which makes their radiation slightly younger than that of other Tanganyikan cichlid tribes. Most scale-eaters evolved in deep-water habitat, perhaps associated with the previously documented radiations of other deep-water dwelling cichlid lineages, and colonized the shallow habitat only recently.
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Avian cooperative breeding: Old hypotheses and new directions.
Heinsohn, R G; Cockburn, A; Mulder, R A
1990-12-01
In cooperatively breeding birds, individuals that appear capable of reproducing on their own may instead assist others with their breeding efforts. Research into avian cooperative breeding has attempted to reconcile the apparent altruism of this behaviour with maximization of inclusive fitness. Most explanations of cooperative breeding have suggested that philopatry is enforced by ecological constraints, such as a shortage of resources critical to breeding. Non-dispersers may then benefit both directly and indirectly from contributing at the nest. Recent research has shown that such benefits may be sufficient to promote philopatry, without the need for ecological constraints, and emphasizes that consideration of both costs and benefits of philopatry is essential for a comprehensive approach to the problem. The growing body of data from long-term studies of different species should combine with an improved phylogenetic perspective on cooperative breeding, to provide a useful base for future comparative analyses and experimentation. Copyright © 1990. Published by Elsevier Ltd.
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Adult sex ratios and their implications for cooperative breeding in birds
Komdeur, Jan; Székely, Tamás; Long, Xiaoyan; Kingma, Sjouke Anne
2017-01-01
Cooperative breeding is a form of breeding system where in addition to a core breeding pair, one or more usually non-breeding individuals provide offspring care. Cooperative breeding is widespread in birds, but its origin and maintenance in contemporary populations are debated. Although deviations
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The ecology of cooperative breeding behaviour.
Shen, Sheng-Feng; Emlen, Stephen T; Koenig, Walter D; Rubenstein, Dustin R
2017-06-01
Ecology is a fundamental driving force for the evolutionary transition from solitary living to breeding cooperatively in groups. However, the fact that both benign and harsh, as well as stable and fluctuating, environments can favour the evolution of cooperative breeding behaviour constitutes a paradox of environmental quality and sociality. Here, we propose a new model - the dual benefits framework - for resolving this paradox. Our framework distinguishes between two categories of grouping benefits - resource defence benefits that derive from group-defended critical resources and collective action benefits that result from social cooperation among group members - and uses insider-outsider conflict theory to simultaneously consider the interests of current group members (insiders) and potential joiners (outsiders) in determining optimal group size. We argue that the different grouping benefits realised from resource defence and collective action profoundly affect insider-outsider conflict resolution, resulting in predictable differences in the per capita productivity, stable group size, kin structure and stability of the social group. We also suggest that different types of environmental variation (spatial vs. temporal) select for societies that form because of the different grouping benefits, thus helping to resolve the paradox of why cooperative breeding evolves in such different types of environments. © 2017 John Wiley & Sons Ltd/CNRS.
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Adult sex ratios and their implications for cooperative breeding in birds.
Komdeur, Jan; Székely, Tamás; Long, Xiaoyan; Kingma, Sjouke A
2017-09-19
Cooperative breeding is a form of breeding system where in addition to a core breeding pair, one or more usually non-breeding individuals provide offspring care. Cooperative breeding is widespread in birds, but its origin and maintenance in contemporary populations are debated. Although deviations in adult sex ratio (ASR, the proportion of males in the adult population) have been hypothesized to influence the occurrence of cooperative breeding because of the resulting surplus of one sex and limited availability of breeding partners, this hypothesis has not been tested across a wide range of taxa. By using data from 188 bird species and phylogenetically controlled analyses, we show that cooperatively breeding species have more male-biased ASRs than non-cooperative species. Importantly, ASR predicts helper sex ratio: in species with more male-biased ASR, helper sex ratio is also more male biased. We also show that offspring sex ratios do not predict ASRs, so that the skewed ASRs emerge during the period when individuals aim to obtain a breeding position or later during adulthood. In line with this result, we found that ASR (among both cooperatively and non-cooperatively breeding species) is inversely related to sex bias in dispersal distance, suggesting that the cost of dispersal is more severe for the further-dispersing sex. As females usually disperse further in birds, this explains the generally male-biased ASR, and in combination with benefits of philopatry for males, this probably explains why ASR is more biased in cooperatively breeding species. Taken together, our results suggest that a sex bias in helping in cooperatively breeding species relates to biased ASRs. We propose that this relationship is driven by sex-specific costs and benefits of dispersal and helping, as well as other demographic factors. Future phylogenetic comparative and experimental work is needed to establish how this relationship emerges.This article is part of the themed issue 'Adult sex
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Fitness consequences of cooperative breeding in the Seychelles warbler
Komdeur, Jan; Richardson, David; Burke, Terry
2006-01-01
Inclusive fitness benefits have been suggested as the selective force behind the evolution of cooperative breeding. Assessing the benefits accrued to individual males and females is crucial to understanding the sex-specific helping behavior observed in many cooperatively breeding species. We
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Family living sets the stage for cooperative breeding and ecological resilience in birds.
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Michael Griesser
2017-06-01
Full Text Available Cooperative breeding is an extreme form of cooperation that evolved in a range of lineages, including arthropods, fish, birds, and mammals. Although cooperative breeding in birds is widespread and well-studied, the conditions that favored its evolution are still unclear. Based on phylogenetic comparative analyses on 3,005 bird species, we demonstrate here that family living acted as an essential stepping stone in the evolution of cooperative breeding in the vast majority of species. First, families formed by prolonging parent-offspring associations beyond nutritional independency, and second, retained offspring began helping at the nest. These findings suggest that assessment of the conditions that favor the evolution of cooperative breeding can be confounded if this process is not considered to include 2 steps. Specifically, phylogenetic linear mixed models show that the formation of families was associated with more productive and seasonal environments, where prolonged parent-offspring associations are likely to be less costly. However, our data show that the subsequent evolution of cooperative breeding was instead linked to environments with variable productivity, where helpers at the nest can buffer reproductive failure in harsh years. The proposed 2-step framework helps resolve current disagreements about the role of environmental forces in the evolution of cooperative breeding and better explains the geographic distribution of this trait. Many geographic hotspots of cooperative breeding have experienced a historical decline in productivity, suggesting that a higher proportion of family-living species could have been able to avoid extinction under harshening conditions through the evolution of cooperative breeding. These findings underscore the importance of considering the potentially different factors that drive different steps in the evolution of complex adaptations.
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Family living sets the stage for cooperative breeding and ecological resilience in birds.
Griesser, Michael; Drobniak, Szymon M; Nakagawa, Shinichi; Botero, Carlos A
2017-06-01
Cooperative breeding is an extreme form of cooperation that evolved in a range of lineages, including arthropods, fish, birds, and mammals. Although cooperative breeding in birds is widespread and well-studied, the conditions that favored its evolution are still unclear. Based on phylogenetic comparative analyses on 3,005 bird species, we demonstrate here that family living acted as an essential stepping stone in the evolution of cooperative breeding in the vast majority of species. First, families formed by prolonging parent-offspring associations beyond nutritional independency, and second, retained offspring began helping at the nest. These findings suggest that assessment of the conditions that favor the evolution of cooperative breeding can be confounded if this process is not considered to include 2 steps. Specifically, phylogenetic linear mixed models show that the formation of families was associated with more productive and seasonal environments, where prolonged parent-offspring associations are likely to be less costly. However, our data show that the subsequent evolution of cooperative breeding was instead linked to environments with variable productivity, where helpers at the nest can buffer reproductive failure in harsh years. The proposed 2-step framework helps resolve current disagreements about the role of environmental forces in the evolution of cooperative breeding and better explains the geographic distribution of this trait. Many geographic hotspots of cooperative breeding have experienced a historical decline in productivity, suggesting that a higher proportion of family-living species could have been able to avoid extinction under harshening conditions through the evolution of cooperative breeding. These findings underscore the importance of considering the potentially different factors that drive different steps in the evolution of complex adaptations.
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The risk of predation favors cooperation among breeding prey
Krama, Tatjana; Berzins, Arnis; Rantala, Markus J
2010-01-01
Empirical studies have shown that animals often focus on short-term benefits under conditions of predation risk, which reduces the likelihood that they will cooperate with others. However, some theoretical studies predict that animals in adverse conditions should not avoid cooperation with their neighbors since it may decrease individual risks and increase long-term benefits of reciprocal help. We experimentally tested these two alternatives to find out whether increased predation risk enhances or diminishes the occurrence of cooperation in mobbing, a common anti-predator behavior, among breeding pied flycatchers, Ficedula hypoleuca. Our results show that birds attended mobs initiated by their neighbors more often, approached the stuffed predator significantly more closely, and mobbed it at a higher intensity in areas where the perceived risk of predation was experimentally increased. This study demonstrates a positive impact of predation risk on cooperation in breeding songbirds, which might help to explain the emergence and evolution of cooperation. PMID:20714404
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Direct benefits and the evolution of female-biased cooperative breeding in Seychelles warblers
Richardson, David S.; Burke, Terry; Komdeur, Jan; Dunn, P.
2002-01-01
Inclusive fitness benefits have been suggested to be a major selective force behind the evolution of cooperative breeding. We investigated the fitness benefits selecting for cooperative breeding in the Seychelles warbler, Acroccphalus sechellensis. A microsatellite-based genotyping method was used
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Environmental stability and the evolution of cooperative breeding in hornbills
Gonzalez, Juan-Carlos T.; Sheldon, Ben C.; Tobias, Joseph A.
2013-01-01
Reproductive cooperation in social animals has been the focus of intensive research, yet the role of environmental factors in promoting such cooperation remains uncertain. A recent global analysis suggested that cooperative breeding in birds is a ‘bet-hedging’ strategy associated with climatic uncertainty, but it is unclear whether this mechanism applies generally or is restricted to the insectivorous passerines that predominate as cooperative breeders at the global scale. Here, we use a phylogenetic framework to assess the effect of climate on the evolution of cooperation in hornbills (Bucerotidae), an avian family characterized by frugivory and carnivory. We show that, in contrast to the global pattern, cooperative reproduction is positively associated with both inter- and intra-annual climatic stability. This reversed relationship implies that hornbills are relatively insensitive to climatic fluctuations, perhaps because of their dietary niche or increased body mass, both of which may remove the need for bet-hedging. We conclude that the relationship between climatic variability and cooperative breeding is inconsistent across taxa, and potentially mediated by life-history variation. These findings help to explain the mixed results of previous studies and highlight the likely shortcomings of global datasets inherently biased towards particular categories. PMID:23926149
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Male and female breeding strategies in a cooperative primate.
Yamamoto, Maria Emilia; Araujo, Arrilton; Arruda, Maria de Fatima; Lima, Ana Karinne Moreira; Siqueira, Jose de Oliveira; Hattori, Wallisen Tadashi
2014-11-01
Marmosets are cooperative breeders organized as extended family groups, but breeding is generally restricted to a single pair. Breeding competition is fierce in female marmosets; males, on the other hand, show low levels of intragroup aggression. We investigated male and female breeding strategies and the resulting reproductive output in 9 wild groups. Reproductive output, tenure of breeding animals, identification of the breeding system, breeding position replacements, migration and infanticide were recorded; also, we recorded grooming and aggression. Replacement of the breeding male or female was observed on nine occasions. On four occasions, the son of the breeding male inherited the breeding post, but we never observed inheritance of a breeding post by a daughter. Mostly, females attained a breeding post by immigrating to a group that had a breeding vacancy. Our results showed that Callithrix jacchus males and females use different strategies to attain a breeding position and maintain it for as long as possible. These strategies prolong the tenure of the breeding position, which is the best way to produce a large number of offspring. This article is part of a Special Issue entitled: Neotropical Behaviour. Copyright © 2014 Elsevier B.V. All rights reserved.
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Group size adjustment to ecological demand in a cooperative breeder.
Zöttl, Markus; Frommen, Joachim G; Taborsky, Michael
2013-04-07
Environmental factors can determine which group size will maximize the fitness of group members. This is particularly important in cooperative breeders, where group members often serve different purposes. Experimental studies are yet lacking to check whether ecologically mediated need for help will change the propensity of dominant group members to accept immigrants. Here, we manipulated the perceived risk of predation for dominant breeders of the cooperatively breeding cichlid fish Neolamprologus pulcher to test their response to unrelated and previously unknown immigrants. Potential immigrants were more readily accepted if groups were exposed to fish predators or egg predators than to herbivorous fish or control situations lacking predation risk. Our data are consistent with both risk dilution and helping effects. Egg predators were presented before spawning, which might suggest that the fish adjust acceptance rates also to a potential future threat. Dominant group members of N. pulcher apparently consider both present and future need of help based on ecological demand. This suggests that acceptance of immigrants and, more generally, tolerance of group members on demand could be a widespread response to ecological conditions in cooperatively breeding animals.
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Bateman's principle is reversed in a cooperatively breeding bird.
Apakupakul, Kathleen; Rubenstein, Dustin R
2015-04-01
Bateman's principle is not only used to explain sex differences in mating behaviour, but also to determine which sex has the greater opportunity for sexual selection. It predicts that the relationship between the number of mates and the number of offspring produced should be stronger for males than for females. Yet, it is unclear whether Bateman's principle holds in cooperatively breeding systems where the strength of selection on traits used in intrasexual competition is high in both sexes. We tested Bateman's principle in the cooperatively breeding superb starling (Lamprotornis superbus), finding that only females showed a significant, positive Bateman gradient. We also found that the opportunity for selection was on average higher in females, but that its strength and direction oscillated through time. These data are consistent with the hypothesis that sexual selection underlies the female trait elaboration observed in superb starlings and other cooperative breeders. Even though the Bateman gradient was steeper for females than for males, the year-to-year oscillation in the strength and direction of the opportunity for selection likely explains why cooperative breeders do not exhibit sexual role reversal. Thus, Bateman's principle may not hold in cooperative breeders where both sexes appear to be under mutually strong sexual selection. © 2015 The Author(s) Published by the Royal Society. All rights reserved.
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B chromosomes have a functional effect on female sex determination in Lake Victoria cichlid fishes.
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Kohta Yoshida
2011-08-01
Full Text Available The endemic cichlid fishes in Lake Victoria are a model system for speciation through adaptive radiation. Although the evolution of the sex-determination system may also play a role in speciation, little is known about the sex-determination system of Lake Victoria cichlids. To understand the evolution of the sex-determination system in these fish, we performed cytogenetic analysis in 11 cichlid species from Lake Victoria. B chromosomes, which are present in addition to standard chromosomes, were found at a high prevalence rate (85% in these cichlids. In one species, B chromosomes were female-specific. Cross-breeding using females with and without the B chromosomes demonstrated that the presence of the B chromosomes leads to a female-biased sex ratio in this species. Although B chromosomes were believed to be selfish genetic elements with little effect on phenotype and to lack protein-coding genes, the present study provides evidence that B chromosomes have a functional effect on female sex determination. FISH analysis using a BAC clone containing B chromosome DNA suggested that the B chromosomes are derived from sex chromosomes. Determination of the nucleotide sequences of this clone (104.5 kb revealed the presence of several protein-coding genes in the B chromosome, suggesting that B chromosomes have the potential to contain functional genes. Because some sex chromosomes in amphibians and arthropods are thought to be derived from B chromosomes, the B chromosomes in Lake Victoria cichlids may represent an evolutionary transition toward the generation of sex chromosomes.
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Machado-Schiaffino, Gonzalo; Henning, Frederico; Meyer, Axel
2014-07-01
The spectacular species richness of cichlids and their diversity in morphology, coloration, and behavior have made them an ideal model for the study of speciation and adaptive evolution. Hypertrophic lips evolved repeatedly and independently in African and Neotropical cichlid radiations. Cichlids with hypertrophic lips forage predominantly in rocky crevices and it has been hypothesized that mechanical stress caused by friction could result in larger lips through phenotypic plasticity. To test the influence of the environment on the size and development of lips, we conducted a series of breeding and feeding experiments on Midas cichlids. Full-sibs of Amphilophus labiatus (thick-lipped) and Amphilophus citrinellus (thin-lipped) each were split into a control group which was fed food from the water column and a treatment group whose food was fixed to substrates. We found strong evidence for phenotypic plasticity on lip area in the thick-lipped species, but not in the thin-lipped species. Intermediate phenotypic values were observed in hybrids from thick- and thin-lipped species reared under "control" conditions. Thus, both a genetic, but also a phenotypic plastic component is involved in the development of hypertrophic lips in Neotropical cichlids. Moreover, species-specific adaptive phenotypic plasticity was found, suggesting that plasticity is selected for in recent thick-lipped species. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.
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Kesler, Dylan C.; Haig, Susan M.
2005-01-01
Limited nest-site availability appears to be an important factor in the evolution of delayed dispersal and cooperative breeding in some cavity-nesting species. The cooperatively breeding Pohnpei subspecies of Micronesian Kingfisher Todiramphus cinnamominus reichenbachii excavates nest cavities from the nests of arboreal termites Nasutitermes spp., or termitaria. In this first published description of nest-sites for this subspecies, we used surveys, remote sensing and radiotelemetry to evaluate the relationship between nest-site availability and co-operation. Results illustrate that nest termitaria are higher in the forest canopy, larger in volume and occur in areas with more contiguous canopy cover than unused termitaria. Nest termitaria were selected independently of the proximity to forest edges and territory boundaries, and we found no difference in characteristics of termitaria used by cooperative groups and breeding pairs. Logistic regression modelling indicated that termitaria with nest-like characteristics were not limited in abundance, suggesting that neither the prospects of inheriting nesting resources nor limited nest-site abundance are probable explanations for delayed dispersal in the Pohnpei subspecies of Micronesian Kingfisher.
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Natalie April van Breukelen
2015-05-01
Full Text Available The convict cichlid (Amatitlania nigrofasciata has been extensively examined in relation to many behavioral topics, such as courtship, pair-bonding, bi-parental care, and territoriality. Recently, this model species has been utilized in studies on genetics, endocrinology, and neuroanatomy, with an ultimate goal of connecting behavior with its underlying mechanisms. The goal of this study was two-fold: (1 profile the circulating levels of plasma 11KT in the male convict cichlid at multiple points during the reproductive cycle and (2 generally compare the hormonal profiles of the widely used laboratory populations and those of a free-living population in the streams of Costa Rica. The results of the field experiment showed that male convict cichlids had higher levels of circulating 11KT during courtship and lower during the parental care and non-breeding phases. The profile of the laboratory population was similar to the profile of the free-living individuals, with significantly higher levels of 11KT occurring during courtship than during parental care, though the level of 11KT during non-breeding phase was elevated in the laboratory. The high levels of 11KT during courtship and low levels of 11KT during parental care found in both the field and the laboratory is similar to what has been reported in other species of teleosts, and may suggest an important function of 11KT in the expression of courtship behavior and the subsequent onset of parental behaviors in this model species.
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Multiscale habitat use and selection in cooperatively breeding Micronesian kingfishers
Kesler, D.C.; Haig, S.M.
2007-01-01
Information about the interaction between behavior and landscape resources is key to directing conservation management for endangered species. We studied multi-scale occurrence, habitat use, and selection in a cooperatively breeding population of Micronesian kingfishers (Todiramphus cinnamominus) on the island of Pohnpei, Federated States of Micronesia. At the landscape level, point-transect surveys resulted in kingfisher detection frequencies that were higher than those reported in 1994, although they remained 15-40% lower than 1983 indices. Integration of spatially explicit vegetation information with survey results indicated that kingfisher detections were positively associated with the amount of wet forest and grass-urban vegetative cover, and they were negatively associated with agricultural forest, secondary vegetation, and upland forest cover types. We used radiotelemetry and remote sensing to evaluate habitat use by individual kingfishers at the home-range scale. A comparison of habitats in Micronesian kingfisher home ranges with those in randomly placed polygons illustrated that birds used more forested areas than were randomly available in the immediate surrounding area. Further, members of cooperatively breeding groups included more forest in their home ranges than birds in pair-breeding territories, and forested portions of study areas appeared to be saturated with territories. Together, these results suggested that forest habitats were limited for Micronesian kingfishers. Thus, protecting and managing forests is important for the restoration of Micronesian kingfishers to the island of Guam (United States Territory), where they are currently extirpated, as well as to maintaining kingfisher populations on the islands of Pohnpei and Palau. Results further indicated that limited forest resources may restrict dispersal opportunities and, therefore, play a role in delayed dispersal and cooperative behaviors in Micronesian kingfishers.
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Temporal diversification of Central American cichlids
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Hulsey C Darrin
2010-09-01
Full Text Available Abstract Background Cichlid fishes are classic examples of adaptive radiation because of their putative tendency to explosively diversify after invading novel environments. To examine whether ecological opportunity increased diversification (speciation minus extinction early in a species-rich cichlid radiation, we determined if Heroine cichlids experienced a burst of diversification following their invasion of Central America. Results We first reconstructed the Heroine phylogeny and determined the basal node to use as the root of Central American Heroine diversification. We then examined the influence of incomplete taxon sampling on this group's diversification patterns. First, we added missing species randomly to the phylogeny and assessed deviations from a constant rate of lineage accumulation. Using a range of species numbers, we failed to recover significant deviations from a pure-birth process and found little support for an early burst of diversification. Then, we examined patterns of lineage accumulation as nodes were increasingly truncated. We assumed that as we removed more recently diverged lineages that sampling would become more complete thereby increasing the power to detect deviations from a pure-birth model. However, truncation of nodes provided even less support for an early burst of diversification. Conclusions Contrary to expectations, our analyses suggest Heroine cichlids did not undergo a burst of diversification when they invaded from South America. Throughout their history in Central America, Heroine cichlids appear to have diversified at a constant rate.
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Cooperative breeding shapes post-fledging survival in an Afrotropical forest bird.
Van de Loock, Dries; Strubbe, Diederik; De Neve, Liesbeth; Githiru, Mwangi; Matthysen, Erik; Lens, Luc
2017-05-01
For avian group living to be evolutionary stable, multiple fitness benefits are expected. Yet, the difficulty of tracking fledglings, and thus estimating their survival rates, limits our knowledge on how such benefits may manifest postfledging. We radio-tagged breeding females of the Afrotropical cooperatively breeding Placid greenbul ( Phyllastrephus placidus) during nesting. Tracking these females after fledging permitted us to locate juvenile birds, their parents, and any helpers present and to build individual fledgling resighting datasets without incurring mortality costs or causing premature fledging due to handling or transmitter effects. A Bayesian framework was used to infer age-specific mortality rates in relation to group size, fledging date, maternal condition, and nestling condition. Postfledging survival was positively related to group size, with fledglings raised in groups with four helpers showing nearly 30% higher survival until independence compared with pair-only offspring, independent of fledging date, maternal condition or nestling condition. Our results demonstrate the importance of studying the early dependency period just after fledging when assessing presumed benefits of cooperative breeding. While studying small, mobile organisms after they leave the nest remains highly challenging, we argue that the telemetric approach proposed here may be a broadly applicable method to obtain unbiased estimates of postfledging survival.
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Medger, Katarina; Bennett, Nigel C; Lutermann, Heike; Ganswindt, Andre
2018-05-18
Dominant females of cooperative breeding species often use aggression to suppress reproduction of subordinate females, resulting in subordinates experiencing stress-related increases in glucocorticoid levels, which may cause reproductive down-regulation. This would suggest a general pattern with higher glucocorticoid levels in subordinate compared to dominant individuals; however, the opposite was found in a number of cooperatively breeding species. Furthermore, breeding females of the cooperatively breeding Damaraland mole-rats (Fukomys damarensis) exhibit very high androgen concentrations during the wet season, presumably to support their breeding monopoly. Hormone analysis in Damaraland mole-rats have typically been measured using plasma and urine, but faecal analysis offers additional advantages especially for field studies on this species. The present study examines the suitability of Damaraland mole-rat faecal samples for determining glucocorticoid metabolite (fGCM) and androgen metabolite (fAM) concentrations using enzyme immunoassays. Using these assays, we further evaluated the effects of breeding status on fGCM and fAM concentrations in wild-caught and captive Damaraland mole-rats. Wild-caught breeding and non-breeding males and females exhibited no differences in fAM concentrations. Immunoreactive fGCM concentrations were only high in male breeders and comparatively low in non-breeders and breeding females. Concentrations of fAMs and fGCMs were similar in captive males and females, but fAM concentrations were elevated in captive compared to wild-caught individuals, which may be related to a higher reproductive activity due to removal from the breeding female. The relatively uniform fAM and fGCM concentrations found in wild-caught mole-rats may be explained by a stable colony structure during the dry season during which this study was conducted. Limited dispersal opportunities result in lower aggression and stress levels within a colony and as a result
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Koenig, Walter D; Walters, Eric L
2015-10-07
Cooperative breeding is generally considered an adaptation to ecological constraints on dispersal and independent breeding, usually due to limited breeding opportunities. Although benefits of cooperative breeding are typically thought of in terms of increased mean reproductive success, it has recently been proposed that this phenomenon may be a bet-hedging strategy that reduces variance in reproductive success (fecundity variance) in populations living in highly variable environments. We tested this hypothesis using long-term data on the polygynandrous acorn woodpecker (Melanerpes formicivorus). In general, fecundity variance decreased with increasing sociality, at least when controlling for annual variation in ecological conditions. Nonetheless, decreased fecundity variance was insufficient to compensate for reduced per capita reproductive success of larger, more social groups, which typically suffered lower estimated mean fitness. We did, however, find evidence that sociality in the form of larger group size resulted in increased fitness in years following a small acorn crop due to reduced fecundity variance. Bet-hedging, although not the factor driving sociality in general, may play a role in driving acorn woodpecker group living when acorns are scarce and ecological conditions are poor. © 2015 The Author(s).
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Hrdy, Sarah B
2016-01-01
This article is part of a Special Issue "Parental Care".Until recently, evolutionists reconstructing mother-infant bonding among human ancestors relied on nonhuman primate models characterized by exclusively maternal care, overlooking the highly variable responsiveness exhibited by mothers in species with obligate reliance on allomaternal care and provisioning. It is now increasingly recognized that apes as large-brained, slow maturing, and nutritionally dependent for so long as early humans were, could not have evolved unless "alloparents" (group members other than genetic parents), in addition to parents, had helped mothers to care for and provision offspring, a rearing system known as "cooperative breeding." Here I review situation-dependent maternal responses ranging from highly possessive to permissive, temporarily distancing, rejecting, or infanticidal, documented for a small subset of cooperatively breeding primates. As in many mammals, primate maternal responsiveness is influenced by physical condition, endocrinological priming, prior experience and local environments (especially related to security). But mothers among primates who evolved as cooperative breeders also appear unusually sensitive to cues of social support. In addition to more "sapient" or rational decision-making, humankind's deep history of cooperative breeding must be considered when trying to understand the extremely variable responsiveness of human mothers. Copyright © 2015 Elsevier Inc. All rights reserved.
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Legge
2000-05-01
I studied the contributions of individuals to incubation and nestling feeding in a population of cooperatively breeding laughing kookaburras, Dacelo novaeguineae. In most cooperatively breeding birds where nest success is limited by nestling starvation, related helpers increase the overall level of provisioning to the nest, thus boosting the production of nondescendent kin. However, although partial brood loss is the largest cause of lost productivity in kookaburra nests, additional helpers failed to increase overall provisioning. Instead, all group members, but especially helpers, reduced their feeding contributions as group size increased. Breeders and helpers reduced the size of prey delivered, and helpers also reduced the number of feeding visits. An important benefit of helping in kookaburras may be to allow all group members to reduce their effort. Within groups, contributions to care depended on status, sex, group size and the brood size. Breeding males delivered the most food. Breeding females provisioned less than their partner, but their effort was comparable to that of male helpers. Female helpers contributed the least food. Incubation effort followed similar patterns. The relatedness of helpers to the brood had no impact on their provisioning. Across all group sizes, helpers generally brought larger items to the nest than breeders. Copyright 2000 The Association for the Study of Animal Behaviour.
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Monogeneans in introduced and native cichlids in México: evidence for transfer.
Jiménez-García, M I; Vidal-Martínez, V M; López-Jiménez, S
2001-08-01
We examined 2 cichlid fish species native to México, Cichlasoma callolepis and C. fenestratum, and 2 introduced African cichlids, Oreochromis aureus and O. niloticus, from 3 localities in southeastern México for monogeneans. Six monogenean species infected the African cichlids: Cichlidogyrus haplochromii, C. dossoui, C. longicornis longicornis, C. sclerosus, C. tilapiae, and Enterogyrus malmbergi. We found all these parasite species, except C. haplochromii and C. dossoui, on the native C. fenestratum and C. callolepis. Prevalences of Cichlidogyrus spp. were 3-10% and abundances ranged from 0.03 +/- 0.2 to 0.1 +/- 0.3 for native cichlids. We only recovered a single E. malmbergi from 1 C. callolepis. We found Sciadicleithrum bravohollisae, a monogenean of native Cichlasoma spp., on the gills of the introduced O. aureus from Lake Catemaco (prevalence 3%, abundance 0.03 +/- 0.2). Although prevalence and abundance in atypical hosts were fairly low, the present findings provide evidence of monogenean transfer from African to American cichlids and vice versa. This is the first record of exotic monogeneans in the genus Cichlidogyrus and Enterogyrus infecting native American cichlid fish. It is also the first record from southeastern México of a native American monogenean infecting introduced African cichlids.
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Directory of Open Access Journals (Sweden)
Christoph Fischer
Full Text Available The cichlid fishes of the East African Great Lakes represent a model especially suited to study adaptive radiation and speciation. With several African cichlid genome projects being in progress, a promising set of closely related genomes is emerging, which is expected to serve as a valuable data base to solve questions on genotype-phenotype relations. The mitochondrial (mt genomes presented here are the first results of the assembly and annotation process for two closely related but eco-morphologically highly distinct Lake Tanganyika cichlids, Petrochromis trewavasae and Tropheus moorii. The genomic sequences comprise 16,588 bp (P. trewavasae and 16,590 bp (T. moorii, and exhibit the typical mitochondrial structure, with 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and a non-coding control region. Analyses confirmed that the two species are very closely related with an overall sequence similarity of 96%. We analyzed the newly generated sequences in the phylogenetic context of 21 published labroid fish mitochondrial genomes. Consistent with other vertebrates, the D-loop region was found to evolve faster than protein-coding genes, which in turn are followed by the rRNAs; the tRNAs vary greatly in the rate of sequence evolution, but on average evolve the slowest. Within the group of coding genes, ND6 evolves most rapidly. Codon usage is similar among examined cichlid tribes and labroid families; although a slight shift in usage patterns down the gene tree could be observed. Despite having a clearly different nucleotide composition, ND6 showed a similar codon usage. C-terminal ends of Cox1 exhibit variations, where the varying number of amino acids is related to the structure of the obtained phylogenetic tree. This variation may be of functional relevance for Cox1 synthesis.
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Directional selection has shaped the oral jaws of Lake Malawi cichlid fishes
Albertson, R. Craig; Streelman, J. Todd; Kocher, Thomas D.
2003-01-01
East African cichlid fishes represent one of the most striking examples of rapid and convergent evolutionary radiation among vertebrates. Models of ecological speciation would suggest that functional divergence in feeding morphology has contributed to the origin and maintenance of cichlid species diversity. However, definitive evidence for the action of natural selection has been missing. Here we use quantitative genetics to identify regions of the cichlid genome responsible for functionally ...
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Kaptijn, R.; Thomese, G.C.F.; van Tilburg, T.G.; Liefbroer, A.C.
2010-01-01
Low birth rates in developed societies reflect women's difficulties in combining work and motherhood. While demographic research has focused on the role of formal childcare in easing this dilemma, evolutionary theory points to the importance of kin. The cooperative breeding hypothesis states that
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Lake Malawi cichlid evolution along a benthic/limnetic axis.
Hulsey, C D; Roberts, R J; Loh, Y-H E; Rupp, M F; Streelman, J T
2013-07-01
Divergence along a benthic to limnetic habitat axis is ubiquitous in aquatic systems. However, this type of habitat divergence has largely been examined in low diversity, high latitude lake systems. In this study, we examined the importance of benthic and limnetic divergence within the incredibly species-rich radiation of Lake Malawi cichlid fishes. Using novel phylogenetic reconstructions, we provided a series of hypotheses regarding the evolutionary relationships among 24 benthic and limnetic species that suggests divergence along this axis has occurred multiple times within Lake Malawi cichlids. Because pectoral fin morphology is often associated with divergence along this habitat axis in other fish groups, we investigated divergence in pectoral fin muscles in these benthic and limnetic cichlid species. We showed that the eight pectoral fin muscles and fin area generally tended to evolve in a tightly correlated manner in the Lake Malawi cichlids. Additionally, we found that larger pectoral fin muscles are strongly associated with the independent evolution of the benthic feeding habit across this group of fish. Evolutionary specialization along a benthic/limnetic axis has occurred multiple times within this tropical lake radiation and has produced repeated convergent matching between exploitation of water column habitats and locomotory morphology.
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Evolution of cichlid vision via trans-regulatory divergence
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O’Quin Kelly E
2012-12-01
Full Text Available Abstract Background Phenotypic evolution may occur through mutations that affect either the structure or expression of protein-coding genes. Although the evolution of color vision has historically been attributed to structural mutations within the opsin genes, recent research has shown that opsin regulatory mutations can also tune photoreceptor sensitivity and color vision. Visual sensitivity in African cichlid fishes varies as a result of the differential expression of seven opsin genes. We crossed cichlid species that express different opsin gene sets and scanned their genome for expression Quantitative Trait Loci (eQTL responsible for these differences. Our results shed light on the role that different structural, cis-, and trans-regulatory mutations play in the evolution of color vision. Results We identified 11 eQTL that contribute to the divergent expression of five opsin genes. On three linkage groups, several eQTL formed regulatory “hotspots” associated with the expression of multiple opsins. Importantly, however, the majority of the eQTL we identified (8/11 or 73% occur on linkage groups located trans to the opsin genes, suggesting that cichlid color vision has evolved primarily via trans-regulatory divergence. By modeling the impact of just two of these trans-regulatory eQTL, we show that opsin regulatory mutations can alter cichlid photoreceptor sensitivity and color vision at least as much as opsin structural mutations can. Conclusions Combined with previous work, we demonstrate that the evolution of cichlid color vision results from the interplay of structural, cis-, and especially trans-regulatory loci. Although there are numerous examples of structural and cis-regulatory mutations that contribute to phenotypic evolution, our results suggest that trans-regulatory mutations could contribute to phenotypic divergence more commonly than previously expected, especially in systems like color vision, where compensatory changes in the
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Incipient speciation driven by hypertrophied lips in Midas cichlid fishes?
Machado-Schiaffino, Gonzalo; Kautt, Andreas F; Torres-Dowdall, Julian; Baumgarten, Lukas; Henning, Frederico; Meyer, Axel
2017-04-01
Sympatric speciation has been debated in evolutionary biology for decades. Although it has gained in acceptance recently, still only a handful of empirical examples are seen as valid (e.g. crater lake cichlids). In this study, we disentangle the role of hypertrophied lips in the repeated adaptive radiations of Nicaraguan crater lake cichlid fish. We assessed the role of disruptive selection and assortative mating during the early stages of divergence and found a functional trade-off in feeding behaviour between thick- and thin-lipped ecotypes, suggesting that this trait is a target of disruptive selection. Thick-lipped fish perform better on nonevasive prey at the cost of a poorer performance on evasive prey. Using enclosures in the wild, we found that thick-lipped fish perform significantly better in rocky than in sandy habitats. We found almost no mixed pairs during two breeding seasons and hence significant assortative mating. Genetic differentiation between ecotypes seems to be related to the time since colonization, being subtle in L. Masaya (1600 generations ago) and absent in the younger L. Apoyeque (<600 generations ago). Genome-wide differentiation between ecotypes was higher in the old source lakes than in the young crater lakes. Our results suggest that hypertrophied lips might be promoting incipient sympatric speciation through divergent selection (ecological divergence in feeding performance) and nonrandom mating (assortative mating) in the young Nicaraguan crater lakes. Nonetheless, further manipulative experiments are needed in order to confirm the role of hypertrophied lips as the main cue for assortative mating. © 2017 John Wiley & Sons Ltd.
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Characterization of V1R receptor (ora) genes in Lake Victoria cichlids.
Ota, Tomoki; Nikaido, Masato; Suzuki, Hikoyu; Hagino-Yamagishi, Kimiko; Okada, Norihiro
2012-05-15
Although olfaction could play a crucial role in underwater habitats by allowing fish to sense a variety of nonvolatile chemical signals, the importance of olfaction in species-rich cichlids is still controversial. In particular, examining whether cichlids rely on olfaction for reproduction is of primary interest to understand the mechanisms of speciation. In the present study, we explored the V1R (also known as ora) genes, which are believed to encode reproductive pheromone receptors in fish, in the genomes of Lake Victoria cichlids. By screening a bacterial artificial chromosome library, we identified all six intact V1R genes (V1R1 to V1R6) that have been reported in other teleost fish. Furthermore, RT-PCR and in situ hybridization analyses showed that all of the V1R genes were expressed in the olfactory epithelium, indicating that these receptors are functional in cichlids. These observations indicate that cichlids use V1R-mediated olfaction in some ways for their social behaviors. Copyright © 2012 Elsevier B.V. All rights reserved.
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Age, sex and social influences on adult survival in the cooperatively breeding Karoo Scrub-robin
Lloyd, Penn; Martin, Thomas E.; Taylor, Andrew; Braae, Anne; Altwegg, Res
2016-01-01
Among cooperatively breeding species, helpers are hypothesised to increase the survival of breeders by reducing breeder workload in offspring care and increased group vigilance against predators. Furthermore, parental nepotism or other benefits of group living may provide a survival benefit to young that delay dispersal to help. We tested these hypotheses in the Karoo Scrub-robin (Cercotrichas coryphaeus), a long-lived, and facultative cooperatively breeding species in which male helpers make substantial contributions to the care of young. We found that annual breeder survival in the presence of helpers did not differ detectably from breeders without helpers or breeders that lost helpers. Furthermore, helpers did not gain a survival benefit from deferred breeding; apparent survival did not differ detectably between male helpers and male breeders followed from one year old. These results are consistent with other studies suggesting a lack of adult survival benefits among species where breeders do not substantially reduce workloads when helpers are present. They are also consistent with the hypothesis that males that delay dispersal make the ‘best of a bad job’ by helping on their natal territory to gain indirect fitness benefits when they are unable to obtain a territory vacancy nearby.
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Transcriptomics of morphological color change in polychromatic Midas cichlids.
Henning, Frederico; Jones, Julia C; Franchini, Paolo; Meyer, Axel
2013-03-13
Animal pigmentation has received much attention in evolutionary biology research due to its strong implications for adaptation and speciation. However, apart from a few cases the genetic changes associated with these evolutionary processes remain largely unknown. The Midas cichlid fish from Central America are an ideal model system for investigating pigmentation traits that may also play a role in speciation. Most Midas cichlids maintain their melanophores and exhibit a grayish (normal) color pattern throughout their lives. A minority of individuals, however, undergo color change and exhibit a distinctive gold or even white coloration in adulthood. The ontogenetic color change in the Midas cichlids may also shed light on the molecular mechanisms underlying pigmentation disorders in humans. Here we use next-generation sequencing (Illumina) RNAseq analyses to compare skin transcriptome-wide expression levels in three distinct stages of color transformation in Midas cichlids. cDNA libraries of scale tissue, for six biological replicates of each group, were generated and sequenced using Illumina technology. Using a combination of three differential expression (DE) analyses we identified 46 candidate genes that showed DE between the color morphs. We find evidence for two key DE patterns: a) genes involved in melanosomal pathways are up-regulated in normally pigmented fish; and b) immediate early and inflammatory response genes were up-regulated in transitional fish, a response that parallels some human skin disorders such as melanoma formation and psoriasis. One of the DE genes segregates with the gold phenotype in a genetic cross and might be associated with incipient speciation in this highly "species-rich" lineage of cichlids. Using transcriptomic analyses we successfully identified key expression differences between different color morphs of Midas cichlid fish. These differentially expressed genes have important implications for our understanding of the molecular
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Directional selection has shaped the oral jaws of Lake Malawi cichlid fishes.
Albertson, R Craig; Streelman, J Todd; Kocher, Thomas D
2003-04-29
East African cichlid fishes represent one of the most striking examples of rapid and convergent evolutionary radiation among vertebrates. Models of ecological speciation would suggest that functional divergence in feeding morphology has contributed to the origin and maintenance of cichlid species diversity. However, definitive evidence for the action of natural selection has been missing. Here we use quantitative genetics to identify regions of the cichlid genome responsible for functionally important shape differences in the oral jaw apparatus. The consistent direction of effects for individual quantitative trait loci suggest that cichlid jaws and teeth evolved in response to strong, divergent selection. Moreover, several chromosomal regions contain a disproportionate number of quantitative trait loci, indicating a prominent role for pleiotropy or genetic linkage in the divergence of this character complex. Of particular interest are genomic intervals with concerted effects on both the length and height of the lower jaw. Coordinated changes in this area of the oral jaw apparatus are predicted to have direct consequences for the speed and strength of jaw movement. Taken together, our results imply that the rapid and replicative nature of cichlid trophic evolution is the result of directional selection on chromosomal packages that encode functionally linked aspects of the craniofacial skeleton.
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Towards a unified theory of cooperative breeding : The role of ecology and life history re-examined
Pen, I.; Weissing, F.J.
2000-01-01
We present quantitative models that unify several adaptive hypotheses for the evolution of cooperative breeding in a single framework: the ecological constraints hypothesis, the life-history hypothesis and the benefits-of-philopatry hypothesis. Our goal is to explain interspecific variation in the
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Temporal patterns of diversification across global cichlid biodiversity (Acanthomorpha: Cichlidae.
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Caleb D McMahan
Full Text Available The contrasting distribution of species diversity across the major lineages of cichlids makes them an ideal group for investigating macroevolutionary processes. In this study, we investigate whether different rates of diversification may explain the disparity in species richness across cichlid lineages globally. We present the most taxonomically robust time-calibrated hypothesis of cichlid evolutionary relationships to date. We then utilize this temporal framework to investigate whether both species-rich and depauperate lineages are associated with rapid shifts in diversification rates and if exceptional species richness can be explained by clade age alone. A single significant rapid rate shift increase is detected within the evolutionary history of the African subfamily Pseudocrenilabrinae, which includes the haplochromins of the East African Great Lakes. Several lineages from the subfamilies Pseudocrenilabrinae (Australotilapiini, Oreochromini and Cichlinae (Heroini exhibit exceptional species richness given their clade age, a net rate of diversification, and relative rates of extinction, indicating that clade age alone is not a sufficient explanation for their increased diversity. Our results indicate that the Neotropical Cichlinae includes lineages that have not experienced a significant rapid burst in diversification when compared to certain African lineages (rift lake. Neotropical cichlids have remained comparatively understudied with regard to macroevolutionary patterns relative to African lineages, and our results indicate that of Neotropical lineages, the tribe Heroini may have an elevated rate of diversification in contrast to other Neotropical cichlids. These findings provide insight into our understanding of the diversification patterns across taxonomically disparate lineages in this diverse clade of freshwater fishes and one of the most species-rich families of vertebrates.
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Yanong, Roy P E; Francis-Floyd, Ruth; Curtis, Eric; Klinger, Ruth Ellen; Cichra, Mary E; Berzins, Ilze K
2002-05-01
Three varieties of a popular African cichlid aquarium species, Pseudotropheus zebra, from 2 tropical fish farms in east central Florida were submitted for diagnostic evaluation because of the development of multifocal green lesions. The percentage of infected fish in these populations varied from 5 to 60%. Fish were otherwise clinically normal. Microscopic examination of fresh and fixed lesions confirmed algal dermatitis, with light invasion of several internal organs in each group. A different alga was identified from each farm. Fish from farm A were infected with Chlorochytrium spp, whereas fish from farm B were infected with Scenedesmus spp. Because of the numbers of fish involved, bath treatments to remove the algae from affected fish from farm B were attempted, with different dosages of several common algaecides including copper sulfate pentahydrate, diuron, and sodium chloride. However, none of these treatments were successful, possibly because of the location of the algae under the scales and within the dermis, and also because of the sequestering effect of the granulomatous response. To our knowledge, this is the first report of algal dermatitis in ornamental cichlids, as well as the first report of Scenedesmus spp infection in any fish.
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A pharyngeal jaw evolutionary innovation facilitated extinction in Lake Victoria cichlids.
McGee, Matthew D; Borstein, Samuel R; Neches, Russell Y; Buescher, Heinz H; Seehausen, Ole; Wainwright, Peter C
2015-11-27
Evolutionary innovations, traits that give species access to previously unoccupied niches, may promote speciation and adaptive radiation. Here, we show that such innovations can also result in competitive inferiority and extinction. We present evidence that the modified pharyngeal jaws of cichlid fishes and several marine fish lineages, a classic example of evolutionary innovation, are not universally beneficial. A large-scale analysis of dietary evolution across marine fish lineages reveals that the innovation compromises access to energy-rich predator niches. We show that this competitive inferiority shaped the adaptive radiation of cichlids in Lake Tanganyika and played a pivotal and previously unrecognized role in the mass extinction of cichlid fishes in Lake Victoria after Nile perch invasion. Copyright © 2015, American Association for the Advancement of Science.
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THE MAIN OUTCOME OF THE RUSSIAN\\BELARUSIAN COOPERATION IN BREEDING OF LEGUMES AND ONION CROPS
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L. P. Shimansky
2014-01-01
Full Text Available The Russian-Belarusian cooperation in breeding of legumes and onion crops has resulted in development of new cultivars of pea (Samorodok, bean (Phaeton and Mignon, onion (Palesskaya znahodka, Patrida and Vermeles, winter garlic (Dubkovsky Asilak, which were included in 2014 in the State Register of the Republic of Belarus.
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Hauber, Mark E; Lacey, Eileen A
2005-11-01
The sex-specific slopes of Bateman's gradients have important implications for understanding animal mating systems, including patterns of sexual selection and reproductive competition. Intersexual differences in the fitness benefits derived from mating with multiple partners are expected to yield distinct patterns of reproductive success for males and females, with variance in direct fitness predicted to be greater among males. These analyses assume that typically all adults are reproductive and that failure to produce offspring is non-adaptive. Among some species of cooperatively breeding birds and mammals, however, non-breeding adult alloparents are common and may comprise the majority of individuals in social groups. The presence of a large number of non-breeding adults, particularly when coupled with greater social suppression of reproduction among females, may alter the relative variance in direct fitness between the sexes, thereby generating an apparent contradiction to Bateman's Paradigm. To explore quantitatively the effects of non-breeding alloparents on variance in reproductive success, we used genetic estimates of parentage and reproductive success drawn from the literature to calculate the relative variability in direct fitness for females and males in alloparental and "other" societies of birds and mammals. Our analyses indicate that in mammals and, to a lesser extent, in birds, variability in direct fitness is greater among females in species characterized by the presence of non-breeding alloparents. These data suggest that social interactions, including social suppression of reproduction, are powerful determinants of individual direct fitness that may modify sex-specific patterns of reproductive variance from those described by Bateman.
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Hauser, Frances E; Ilves, Katriina L; Schott, Ryan K; Castiglione, Gianni M; López-Fernández, Hernán; Chang, Belinda S W
2017-10-01
Cichlids encompass one of the most diverse groups of fishes in South and Central America, and show extensive variation in life history, morphology, and colouration. While studies of visual system evolution in cichlids have focussed largely on the African rift lake species flocks, Neotropical cichlids offer a unique opportunity to investigate visual system evolution at broader temporal and geographic scales. South American cichlid colonization of Central America has likely promoted accelerated rates of morphological evolution in Central American lineages as they encountered reduced competition, renewed ecological opportunity, and novel aquatic habitats. To investigate whether such transitions have influenced molecular evolution of vision in Central American cichlids, we sequenced the dim-light rhodopsin gene in 101 Neotropical cichlid species, spanning the diversity of the clade. We find strong evidence for increased rates of evolution in Central American cichlid rhodopsin relative to South American lineages, and identify several sites under positive selection in rhodopsin that likely contribute to adaptation to different photic environments. We expressed a Neotropical cichlid rhodopsin protein invitro for the first time, and found that while its spectral tuning properties were characteristic of typical vertebrate rhodopsin pigments, the rate of decay of its active signalling form was much slower, consistent with dim light adaptation in other vertebrate rhodopsins. Using site-directed mutagenesis combined with spectroscopic assays, we found that a key amino acid substitution present in some Central American cichlids accelerates the rate of decay of active rhodopsin, which may mediate adaptation to clear water habitats. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
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Comparative morphology among northern populations of breeding Cooper's Hawks
Rosenfield, Robert N.; Rosenfield, Laura J.; Bielefeldt, John; Murphy, Robert K.; Stewart, Andrew C.; Stout, William E.; Driscoll, Timothy G.; Bozek, Michael A.
2010-01-01
Few studies at a broad geographical scale have characterized intraspecific variation in morphology of woodland hawks in the genus Accipiter. From 1999 to 2007 we investigated morphological variation in large samples of live Cooper's Hawks (A. cooperii) nesting in four study areas: coniferous woodland around Victoria, British Columbia, Canada, isolated deciduous woodlands in short-grass prairies of northwestern North Dakota, towns and rural deciduous woodlands along the border of North Dakota and Minnesota, and urban and rural mixed deciduous and coniferous landscapes of Wisconsin. These sites span 2660 km across the northern part of the species' breeding range. We measured body mass (i.e., size), wing chord, tail length, tarsus diameter, hallux length, and culmen length of breeding adults, finding significant and clinal variation in body mass (or size). The smallest and most similar-sized birds occurred in British Columbia and western North Dakota, larger birds along the border between North Dakota and Minnesota, and the largest birds in Wisconsin. Several other characters varied significantly when mass was used as a covariate. Variation by study site in mean indices of sexual size dimorphism was negligible and not significant. We speculate that the morphological differences we found, in part, are the result of geographic isolation, where diets, migratory behavior, and structural characteristics of nesting habitats vary across landscape types.
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Directory of Open Access Journals (Sweden)
Salzburger Walter
2011-04-01
Full Text Available Abstract Background Phenotypic evolution and its role in the diversification of organisms is a central topic in evolutionary biology. A neglected factor during the modern evolutionary synthesis, adaptive phenotypic plasticity, more recently attracted the attention of many evolutionary biologists and is now recognized as an important ingredient in both population persistence and diversification. The traits and directions in which an ancestral source population displays phenotypic plasticity might partly determine the trajectories in morphospace, which are accessible for an adaptive radiation, starting from the colonization of a novel environment. In the case of repeated colonizations of similar environments from the same source population this "flexible stem" hypothesis predicts similar phenotypes to arise in repeated subsequent radiations. The Midas Cichlid (Amphilophus spp. in Nicaragua has radiated in parallel in several crater-lakes seeded by populations originating from the Nicaraguan Great Lakes. Here, we tested phenotypic plasticity in the pharyngeal jaw of Midas Cichlids. The pharyngeal jaw apparatus of cichlids, a second set of jaws functionally decoupled from the oral ones, is known to mediate ecological specialization and often differs strongly between sister-species. Results We performed a common garden experiment raising three groups of Midas cichlids on food differing in hardness and calcium content. Analyzing the lower pharyngeal jaw-bones we find significant differences between diet groups qualitatively resembling the differences found between specialized species. Observed differences in pharyngeal jaw expression between groups were attributable to the diet's mechanical resistance, whereas surplus calcium in the diet was not found to be of importance. Conclusions The pharyngeal jaw apparatus of Midas Cichlids can be expressed plastically if stimulated mechanically during feeding. Since this trait is commonly differentiated - among
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Muschick, Moritz; Barluenga, Marta; Salzburger, Walter; Meyer, Axel
2011-04-30
Phenotypic evolution and its role in the diversification of organisms is a central topic in evolutionary biology. A neglected factor during the modern evolutionary synthesis, adaptive phenotypic plasticity, more recently attracted the attention of many evolutionary biologists and is now recognized as an important ingredient in both population persistence and diversification. The traits and directions in which an ancestral source population displays phenotypic plasticity might partly determine the trajectories in morphospace, which are accessible for an adaptive radiation, starting from the colonization of a novel environment. In the case of repeated colonizations of similar environments from the same source population this "flexible stem" hypothesis predicts similar phenotypes to arise in repeated subsequent radiations. The Midas Cichlid (Amphilophus spp.) in Nicaragua has radiated in parallel in several crater-lakes seeded by populations originating from the Nicaraguan Great Lakes. Here, we tested phenotypic plasticity in the pharyngeal jaw of Midas Cichlids. The pharyngeal jaw apparatus of cichlids, a second set of jaws functionally decoupled from the oral ones, is known to mediate ecological specialization and often differs strongly between sister-species. We performed a common garden experiment raising three groups of Midas cichlids on food differing in hardness and calcium content. Analyzing the lower pharyngeal jaw-bones we find significant differences between diet groups qualitatively resembling the differences found between specialized species. Observed differences in pharyngeal jaw expression between groups were attributable to the diet's mechanical resistance, whereas surplus calcium in the diet was not found to be of importance. The pharyngeal jaw apparatus of Midas Cichlids can be expressed plastically if stimulated mechanically during feeding. Since this trait is commonly differentiated--among other traits--between Midas Cichlid species, its plasticity
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Paperno, R.; Ruiz-Carus, R.; Krebs, J.M.; McIvor, C.C.
2008-01-01
Introduced exotic species are a well-recognized problem in Florida's subtropical ecosystems. The presence of the exotic Mayan cichlid (Cichlasoma urophthalmus) was first confirmed in Florida in 1983, when numerous individuals were found in the northeastern Florida Bay. Since then, this species has continued to expand its range northward. The capture, beginning in October 2004 to present, of large numbers of Mayan cichlids from central Florida's east- and west-coast mangrove systems north of 28°N latitude is documented here. Mayan cichlids in a wide range of sizes (estimated ages 0-7 years) at both east- and west-coast sites were collected. In addition, macroscopic examination of gonads showed the presence of developing eggs. The occurrence of multiple age-classes, maturing individuals, cichlid nests, and juveniles, plus repeated collections over a four-year period, indicates that the Mayan cichlid is successfully reproducing and surviving the average winter temperatures in some estuarine waters in central Florida.
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Biological Diversity and Resilience: Lessons from the Recovery of Cichlid Species in Lake Victoria
Directory of Open Access Journals (Sweden)
Alex O. Awiti
2011-03-01
Full Text Available A fundamental feature of the Anthropocene is the inexorable erosion of the self-repairing capacity or adaptive renewal of natural systems because of natural perturbation, exploitation, or management failure. The concept of resilience offers a systematic framework for understanding the dynamics and variables that govern response dynamics of ecosystems. Resilience of haplochromine cichlids is assessed using limnological and biodiversity changes in Lake Victoria, the world's second largest freshwater lake, over the last five decades. The review explores the resurgence of the haplochromine cichlids using Holling's adaptive renewal cycle and attempts to illustrate how resilience-based management approaches might learn from an inadvertent management experiment. The introduction in the 1980s of the Nile perch (Lates niloticus, a fecund and voracious predator of the endemic phytoplankton feeding haplochromine cichlids, anthropogenic eutrophication, and deep water hypoxia have combined in a synergistic way to increase the vulnerability of the lake ecosystem to perturbations that were hitherto absorbed. However, the upsurge in commercial Nile perch fishing appears to be enabling the resurgence of the haplochromine cichlids. The resurgence of haplochromine cichlids is characterized by phenotypic plasticity, ecological and life history traits and demonstrates the critical role of response diversity in the maintenance of systems resilience. Resilience of the haplochromine cichlids resides in the requisite functional response diversity and habitat diversity that provide the resources for renewal and regeneration. This paper concludes that management of Nile perch fisheries and control of nutrient loading into Lake Victoria could halt or reverse eutrophication, hence offer the best promise for a diverse, productive, and resilient social-ecological system.
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Lake Tanganyika--a 'melting pot' of ancient and young cichlid lineages (Teleostei: Cichlidae?
Directory of Open Access Journals (Sweden)
Juliane D Weiss
Full Text Available A long history of research focused on the East Africa cichlid radiations (EAR revealed discrepancies between mtDNA and nuclear phylogenies, suggesting that interspecific hybridisation may have been significant during the radiation of these fishes. The approximately 250 cichlid species of Lake Tanganyika have their roots in a monophyletic African cichlid assemblage, but controversies remain about the precise phylogenetic origin and placement of different lineages and consequently about L. Tanganyika colonization scenarios. 3312 AFLP loci and the mitochondrial ND2 gene were genotyped for 91 species representing almost all major lacustrine and riverine haplotilapiine east African cichlid lineages with a focus on L. Tanganyika endemics. Explicitly testing for the possibility of ancient hybridisation events, a comprehensive phylogenetic network hypothesis is proposed for the origin and diversification of L. Tanganyika cichlids. Inference of discordant phylogenetic signal strongly suggests that the genomes of two endemic L. Tanganyika tribes, Eretmodini and Tropheini, are composed of an ancient mixture of riverine and lacustrine lineages. For the first time a strong monophyly signal of all non-haplochromine mouthbrooding species endemic to L. Tanganyika ("ancient mouthbrooders" was detected. Further, in the genomes of early diverging L. Tanganyika endemics Trematocarini, Bathybatini, Hemibatini and Boulengerochromis genetic components of other lineages belonging to the East African Radiation appear to be present. In combination with recent palaeo-geological results showing that tectonic activity in the L. Tanganyika region resulted in highly dynamic and heterogeneous landscape evolution over the Neogene and Pleistocene, the novel phylogenetic data render a single lacustrine basin as the geographical cradle of the endemic L. Tanganyika cichlid lineages unlikely. Instead a scenario of a pre-rift origin of several independent L. Tanganyika precursor
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Directory of Open Access Journals (Sweden)
C. Darrin Hulsey
2017-09-01
Full Text Available The independent evolution of the two toothed jaws of cichlid fishes is thought to have promoted their unparalleled ecological divergence and species richness. However, dental divergence in cichlids could exhibit substantial genetic covariance and this could dictate how traits like tooth numbers evolve in different African Lakes and on their two jaws. To test this hypothesis, we used a hybrid mapping cross of two trophically divergent Lake Victoria species (Haplochromis chilotes × Haplochromis nyererei to examine genomic regions associated with cichlid tooth diversity. Surprisingly, a similar genomic region was found to be associated with oral jaw tooth numbers in cichlids from both Lake Malawi and Lake Victoria. Likewise, this same genomic location was associated with variation in pharyngeal jaw tooth numbers. Similar relationships between tooth numbers on the two jaws in both our Victoria hybrid population and across the phylogenetic diversity of Malawi cichlids additionally suggests that tooth numbers on the two jaws of haplochromine cichlids might generally coevolve owing to shared genetic underpinnings. Integrated, rather than independent, genomic architectures could be key to the incomparable evolutionary divergence and convergence in cichlid tooth numbers.
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Class I mhc genes of cichlid fishes: identification, expression, and polymorphism.
Sato, A; Klein, D; Sültmann, H; Figueroa, F; O'hUigin, C; Klein, J
1997-01-01
Cichlid fishes of the East African Rift Valley lakes constitute an important model of adaptive radiation. Explosive speciation in the Great Lakes, in some cases as recently as 12 400 years ago, generated large species flocks that have been the focus of evolutionary studies for some time. The studies have, however, been hampered by the paucity of biochemical markers for phylogenetic reconstruction. Here, we describe a set of markers which should help to alleviate this problem. They are the class I genes of the major histocompatibility complex. We provide evidence for the existence of at least 17 class I loci in cichlid fishes, and for extensive polymorphism of three of these loci. Since the polymorphism has a trans-species character, it will be possible to use it in investigating the founding events of the individual species. The sequences of the cichlid class I fishes support the monophyly of actinopterygian fish on the one hand, and of tetrapods on the other.
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Sonsthagen, Sarah A.; Rosenfield, Robert N.; Bielefeldt, John; Murphy, Robert K.; Stewart, Andrew C.; Stout, William C.; Driscoll, Timothy G.; Bozek, Michael A.; Sloss, Brian L.; Talbot, Sandra L.
2012-01-01
Cooper's Hawk (Accipiter cooperii) populations breeding in the northern portion of the species' range exhibit variation in morphological traits that conforms to predictions based on differences in prey size, tree stand density, and migratory behavior. We examined genetic structure and gene flow and compared divergence at morphological traits (PST) and genetic markers (FST) to elucidate mechanisms (selection or genetic drift) that promote morphological diversification among Cooper's Hawk populations. Cooper's Hawks appear to conform to the genetic pattern of an east-west divide. Populations in British Columbia are genetically differentiated from north-central populations (Wisconsin, Minnesota, and North Dakota; pairwise microsatellite FST= 0.031-0.050; mitochondrial DNA ΦST = 0.177-0.204), which suggests that Cooper's Hawks were restricted to at least two Pleistocene glacial refugia. The strength of the Rocky Mountains—Great Plains area as a barrier to dispersal is further supported by restricted gene-flow rates between British Columbia and other sampled breeding populations. Divergence in morphological traits (PST) was also observed across study areas, but with British Columbia and North Dakota differentiated from Wisconsin and Minnesota, a pattern not predicted on the basis of FST and ΦST interpopulation estimates. Comparison of PSTand FSTestimates suggests that heterogeneous selection may be acting on Cooper's Hawks in the northern portion of their distribution, which is consistent with hypotheses that variation in prey mass and migratory behavior among populations may be influencing overall body size and wing chord. We were unable to distinguish between the effects of genetic drift and selection on tail length in the study populations.
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Rapid and Parallel Adaptive Evolution of the Visual System of Neotropical Midas Cichlid Fishes.
Torres-Dowdall, Julián; Pierotti, Michele E R; Härer, Andreas; Karagic, Nidal; Woltering, Joost M; Henning, Frederico; Elmer, Kathryn R; Meyer, Axel
2017-10-01
Midas cichlid fish are a Central American species flock containing 13 described species that has been dated to only a few thousand years old, a historical timescale infrequently associated with speciation. Their radiation involved the colonization of several clear water crater lakes from two turbid great lakes. Therefore, Midas cichlids have been subjected to widely varying photic conditions during their radiation. Being a primary signal relay for information from the environment to the organism, the visual system is under continuing selective pressure and a prime organ system for accumulating adaptive changes during speciation, particularly in the case of dramatic shifts in photic conditions. Here, we characterize the full visual system of Midas cichlids at organismal and genetic levels, to determine what types of adaptive changes evolved within the short time span of their radiation. We show that Midas cichlids have a diverse visual system with unexpectedly high intra- and interspecific variation in color vision sensitivity and lens transmittance. Midas cichlid populations in the clear crater lakes have convergently evolved visual sensitivities shifted toward shorter wavelengths compared with the ancestral populations from the turbid great lakes. This divergence in sensitivity is driven by changes in chromophore usage, differential opsin expression, opsin coexpression, and to a lesser degree by opsin coding sequence variation. The visual system of Midas cichlids has the evolutionary capacity to rapidly integrate multiple adaptations to changing light environments. Our data may indicate that, in early stages of divergence, changes in opsin regulation could precede changes in opsin coding sequence evolution. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
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The ecological and genetic basis of convergent thick-lipped phenotypes in cichlid fishes.
Colombo, Marco; Diepeveen, Eveline T; Muschick, Moritz; Santos, M Emilia; Indermaur, Adrian; Boileau, Nicolas; Barluenga, Marta; Salzburger, Walter
2013-02-01
The evolution of convergent phenotypes is one of the most interesting outcomes of replicate adaptive radiations. Remarkable cases of convergence involve the thick-lipped phenotype found across cichlid species flocks in the East African Great Lakes. Unlike most other convergent forms in cichlids, which are restricted to East Africa, the thick-lipped phenotype also occurs elsewhere, for example in the Central American Midas Cichlid assemblage. Here, we use an ecological genomic approach to study the function, the evolution and the genetic basis of this phenotype in two independent cichlid adaptive radiations on two continents. We applied phylogenetic, demographic, geometric morphometric and stomach content analyses to an African (Lobochilotes labiatus) and a Central American (Amphilophus labiatus) thick-lipped species. We found that similar morphological adaptations occur in both thick-lipped species and that the 'fleshy' lips are associated with hard-shelled prey in the form of molluscs and invertebrates. We then used comparative Illumina RNA sequencing of thick vs. normal lip tissue in East African cichlids and identified a set of 141 candidate genes that appear to be involved in the morphogenesis of this trait. A more detailed analysis of six of these genes led to three strong candidates: Actb, Cldn7 and Copb. The function of these genes can be linked to the loose connective tissue constituting the fleshy lips. Similar trends in gene expression between African and Central American thick-lipped species appear to indicate that an overlapping set of genes was independently recruited to build this particular phenotype in both lineages. © 2012 Blackwell Publishing Ltd.
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Convergence of gut microbiotas in the adaptive radiations of African cichlid fishes.
Baldo, Laura; Pretus, Joan Lluís; Riera, Joan Lluís; Musilova, Zuzana; Bitja Nyom, Arnold Roger; Salzburger, Walter
2017-09-01
Ecoevolutionary dynamics of the gut microbiota at the macroscale level, that is, in across-species comparisons, are largely driven by ecological variables and host genotype. The repeated explosive radiations of African cichlid fishes in distinct lakes, following a dietary diversification in a context of reduced genetic diversity, provide a natural setup to explore convergence, divergence and repeatability in patterns of microbiota dynamics as a function of the host diet, phylogeny and environment. Here we characterized by 16S rRNA amplicon sequencing the gut microbiota of 29 cichlid species from two distinct lakes/radiations (Tanganyika and Barombi Mbo) and across a broad dietary and phylogenetic range. Within each lake, a significant deviation between a carnivorous and herbivorous lifestyle was found. Herbivore species were characterized by an increased bacterial taxonomic and functional diversity and converged in key compositional and functional community aspects. Despite a significant lake effect on the microbiota structure, this process has occurred with remarkable parallels in the two lakes. A metabolic signature most likely explains this trend, as indicated by a significant enrichment in herbivores/omnivores of bacterial taxa and functions associated with fiber degradation and detoxification of plant chemical compounds. Overall, compositional and functional aspects of the gut microbiota individually and altogether validate and predict main cichlid dietary habits, suggesting a fundamental role of gut bacteria in cichlid niche expansion and adaptation.
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Polačik, Matej; Smith, Carl; Honza, Marcel; Reichard, Martin
2018-01-01
Obligate brood parasites manipulate other species into raising their offspring. Avian and insect brood parasitic systems demonstrate how interacting species engage in reciprocal coevolutionary arms races through behavioral and morphological adaptations and counteradaptations. Mouthbrooding cichlid fishes are renowned for their remarkable evolutionary radiations and complex behaviors. In Lake Tanganyika, mouthbrooding cichlids are exploited by the only obligate nonavian vertebrate brood parasite, the cuckoo catfish Synodontis multipunctatus. We show that coevolutionary history and individual learning both have a major impact on the success of cuckoo catfish parasitism between coevolved sympatric and evolutionarily naïve allopatric cichlid species. The rate of cuckoo catfish parasitism in coevolved Tanganyikan hosts was 3 to 11 times lower than in evolutionarily naïve cichlids. Moreover, using experimental infections, we demonstrate that parasite egg rejection in sympatric hosts was much higher, leading to seven times greater parasite survival in evolutionarily naïve than sympatric hosts. However, a high rejection frequency of parasitic catfish eggs by coevolved sympatric hosts came at a cost of increased rejection of their own eggs. A significant cost of catfish parasitism was universal, except for coevolved sympatric cichlid species with previous experience of catfish parasitism, demonstrating that learning and individual experience both contribute to a successful host response.
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THE BEHAVIOUR AND BRAIN FUNCTION OF THE CICHLID FISH ...
African Journals Online (AJOL)
male and female conspecifics on a visual basis. ... Brain Function, Teleost, telencephalon, Cichlid fish behaviour, limbic system, hippocampus. ...... The effects of forebrain ablations on the behaviour of H. philander cannot be satisfactorily.
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Groenewoud, Frank; Kingma, Sjouke A; Hammers, Martijn; Dugdale, Hannah L; Burke, Terry; Richardson, David S; Komdeur, Jan
2018-05-11
1.In many cooperatively breeding animals, a combination of ecological constraints and benefits of philopatry favours offspring taking a subordinate position on the natal territory instead of dispersing to breed independently. However, in many species individuals disperse to a subordinate position in a non-natal group ("subordinate between-group" dispersal), despite losing the kin-selected and nepotistic benefits of remaining in the natal group. It is unclear which social, genetic and ecological factors drive between-group dispersal. 2.We aim to elucidate the adaptive significance of subordinate between-group dispersal by examining which factors promote such dispersal, whether subordinates gain improved ecological and social conditions by joining a non-natal group, and whether between-group dispersal results in increased lifetime reproductive success and survival. 3.Using a long-term dataset on the cooperatively-breeding Seychelles warbler (Acrocephalus sechellensis), we investigated 4.how a suite of proximate factors (food availability, group composition, age and sex of focal individuals, population density) promote subordinate between-group dispersal by comparing such dispersers with subordinates that dispersed to a dominant position or became floaters. We then analysed whether subordinates that moved to a dominant or non-natal subordinate position, or became floaters, gained improved conditions relative to the natal territory, and compared fitness components between the three dispersal strategies. 5.We show that individuals that joined another group as non-natal subordinates were mainly female and that, similar to floating, between-group dispersal was associated with social and demographic factors that constrained dispersal to an independent breeding position. Between-group dispersal was not driven by improved ecological or social conditions in the new territory and did not result in higher survival. Instead, between-group dispersing females often became co
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New record of a fossil haplotilapiine cichlid from Central Kenya
Directory of Open Access Journals (Sweden)
Stefanie B. R. Penk
2015-11-01
Full Text Available African freshwater cichlids (Cichlidae: Pseudocrenilabrinae are well known for their exceptionally great diversity and their capability of rapid speciation as well as diverse adaptations. The extant Pseudocrenilabrinae can be grouped into 27 tribes, with more than 2000 species harbored in the Great Lakes and surrounding water bodies of the East African Rift System. However, this unique diversity is not reflected in the fossil record because fossil cichlids were predominantly reported based on isolated teeth and bones. Moreover, the few articulated specimens that are known have not been analyzed sufficiently with regard to their systematic position due to lack of comparative material. Here we present a new extraordinarily well-preserved cichlid fish fossil from the Middle Miocene (c. 12.5 Ma Lagerstaette Kabchore, which was recovered during recent fieldwork in the Tugen Hills (Baringo County, Central Kenya Rift. Based on the evidence of tricuspid teeth, the Kabchore fossil can be assigned to the subclade of the Haplotilapiines within the Pseudocrenilabrinae. The multivariate analysis of a large meristic data set, derived from 1014 extant specimens (encompassing all main lineages of Haplotilapiines and usage of available osteological data suggest that this fossil is most likely related to one of the three haplotilapiine tribes Tilapiini, Haplochromini or Oreochromini. Moreover, the fossil specimen closely resembles the extinct cichlid Oreochromis martyni (Van Couvering, 1982, previously described as species of Sarotherodon from the Middle Miocene alkaline Kapkiamu Lake in the Tugen Hills. The analysis of the greatly preserved fossil fish specimen from Kabchore definitely supplements the fragmentary fossil record of Africa’s Cichlidae and will afford new insights into its evolutionary history. We also expect that this fossil will be useful as calibration point for new divergence-time estimates.
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Directory of Open Access Journals (Sweden)
Sarah E Steele
Full Text Available Body size is an important correlate of life history, ecology and distribution of species. Despite this, very little is known about body size evolution in fishes, particularly freshwater fishes of the Neotropics where species and body size diversity are relatively high. Phylogenetic history and body size data were used to explore body size frequency distributions in Neotropical cichlids, a broadly distributed and ecologically diverse group of fishes that is highly representative of body size diversity in Neotropical freshwater fishes. We test for divergence, phylogenetic autocorrelation and among-clade partitioning of body size space. Neotropical cichlids show low phylogenetic autocorrelation and divergence within and among taxonomic levels. Three distinct regions of body size space were identified from body size frequency distributions at various taxonomic levels corresponding to subclades of the most diverse tribe, Geophagini. These regions suggest that lineages may be evolving towards particular size optima that may be tied to specific ecological roles. The diversification of Geophagini appears to constrain the evolution of body size among other Neotropical cichlid lineages; non-Geophagini clades show lower species-richness in body size regions shared with Geophagini. Neotropical cichlid genera show less divergence and extreme body size than expected within and among tribes. Body size divergence among species may instead be present or linked to ecology at the community assembly scale.
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Directory of Open Access Journals (Sweden)
Martin L. Hing
2017-08-01
Full Text Available Why do we observe so many examples in nature in which individuals routinely delay or completely forgo their own reproductive opportunities in order to join and remain within a group? Cooperative breeding theory provides a rich framework with which to study the factors that may influence the costs and benefits of remaining philopatric as a non-breeder. This is often viewed as an initial step in the development of costly helping behavior provided by non-breeding subordinates. Despite many excellent empirical studies testing key concepts of the theory, there is still debate regarding the relative importance of various evolutionary forces, suggesting that there may not be a general explanation but rather a dynamic and taxonomically varied combination of factors influencing the evolution and maintenance of sociality. Here, we explore two potential improvements in the study of sociality that could aid in the progress of this field. The first addresses the fact that empirical studies of social evolution are typically conducted using either comparative, observational or manipulative methodologies. Instead, we suggest a holistic approach, whereby observational and experimental studies are designed with the explicit view of advancing comparative analyses of sociality for the taxon, and in tandem, where comparative work informs targeted research effort on specific (usually understudied species within the lineage. A second improvement relates to the broadening of tests of cooperative breeding theory to include taxa where subordinates do not necessarily provide active cooperation within the group. The original bias toward “helpful subordinates” arose from a focus on terrestrial taxa. However, recent consideration of other taxa, especially marine taxa, is slowly revealing that the theory can and should encompass a continuum of cooperative social systems, including those where subordinates do not actively help. This review summarizes the major hypotheses
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Peterson, Erin N.; Cline, Maggie E.; Moore, Emily C.; Roberts, Natalie B.; Roberts, Reade B.
2017-06-01
East African cichlids display extensive variation in sex determination systems. The species Astatotilapia calliptera is one of the few cichlids that reside both in Lake Malawi and in surrounding waterways. A. calliptera is of interest in evolutionary studies as a putative immediate outgroup species for the Lake Malawi species flock and possibly as a prototype ancestor-like species for the radiation. Here, we use linkage mapping to test association of sex in A. calliptera with loci that have been previously associated with genetic sex determination in East African cichlid species. We identify a male heterogametic XY system segregating at linkage group (LG) 7 in an A. calliptera line that originated from Lake Malawi, at a locus previously shown to act as an XY sex determination system in multiple species of Lake Malawi cichlids. Significant association of genetic markers and sex produce a broad genetic interval of approximately 26 megabases (Mb) using the Nile tilapia genome to orient markers; however, we note that the marker with the strongest association with sex is near a gene that acts as a master sex determiner in other fish species. We demonstrate that alleles of the marker are perfectly associated with sex in Metriaclima mbenjii, a species from the rock-dwelling clade of Lake Malawi. While we do not rule out the possibility of other sex determination loci in A. calliptera, this study provides a foundation for fine mapping of the cichlid sex determination gene on LG7 and evolutionary context regarding the origin and persistence of the LG7 XY across diverse, rapidly evolving lineages.
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Ishiwata, Ryosuke R; Morioka, Masaki S; Ogishima, Soichi; Tanaka, Hiroshi
2009-02-15
BioCichlid is a 3D visualization system of time-course microarray data on molecular networks, aiming at interpretation of gene expression data by transcriptional relationships based on the central dogma with physical and genetic interactions. BioCichlid visualizes both physical (protein) and genetic (regulatory) network layers, and provides animation of time-course gene expression data on the genetic network layer. Transcriptional regulations are represented to bridge the physical network (transcription factors) and genetic network (regulated genes) layers, thus integrating promoter analysis into the pathway mapping. BioCichlid enhances the interpretation of microarray data and allows for revealing the underlying mechanisms causing differential gene expressions. BioCichlid is freely available and can be accessed at http://newton.tmd.ac.jp/. Source codes for both biocichlid server and client are also available.
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[Feeding habits of cichlid species (Perciformes: Cichlidae) in Caobas lake, Quintana Roo, Mexico].
Valtierra-Vega, M T; Schmitter-Soto, J J
2000-01-01
Feeding habits of seven cichlid species (Archocentrus octofasciatus, A. spilurus, "Cichlasoma" robertsoni, "C." synspilum, "C." urophthalmus, Petenia splendida, Thorichthys meeki) in Lake Caobas, southern Yucatan Peninsula, were studied. Samples were taken with enclosure and cast nets during the dry and rainy seasons of 1995 (day and night). The environment was characterized by measuring temperature, conductivity and pH. All individuals were below 41 mm SL (N = 281). Frequency of occurrence and prey abundance were analyzed. Main prey items were chironomids, mites, copepods, cladocerans, and ostracods. The cichlids fed mainly on zooplankton, with the partial exceptions of P. splendida (piscivore), "C." synspilum and A. spilurus (herbivores). A cluster analysis showed that the most similar trophic spectra were those of T. meeki, "C." robertsoni and "C." salvini, which were also the least diverse. "C." synspilum and A. spilurus had an intermediate distance between their diets and those of other species. The species with the most distinctive feeding composition were P. splendida (with the most diverse and equitable diet) and the omnivore A. octofasciatus (whose diet was the richest one). T. meeki showed quantitative diel, ontogenetic, and seasonal diet changes, but none between sexes. "C." robertsoni, "C." salvini and "C." synspilum differ in food habits in Caobas and in other localities, a fact that underscores the trophic adaptability of cichlids. Trophic overlap between cichlids in Caobas could imply absence of competition, perhaps because resources are abundant in the ecosystem.
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The behaviour and brain function of the Cichlid fish ...
African Journals Online (AJOL)
... the teleost forebrain houses a primitive limbic system the main functions of which would be general arousal and the selection of appropriate responses to the incoming external and endogenous (motivational) stimuli. Keywords: Brain Function, Teleost, telencephalon, Cichlid fish behaviour, limbic system, hippocampus ...
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Adaptive responses to environmental changes in Lake Victoria cichlids
Rijssel, Jacobus Cornelis van (Jacco)
2014-01-01
Lake Victoria cichlids show the fastest vertebrate adaptive radiation known which is why they function as a model organism to study evolution. In the past 40 years, Lake Victoria experienced severe environmental changes including the boom of the introduced, predatory Nile perch and eutrophication.
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Arbour, Jessica Hilary; López-Fernández, Hernán
2016-08-17
Adaptive radiations have been hypothesized to contribute broadly to the diversity of organisms. Models of adaptive radiation predict that ecological opportunity and ecological release, the availability of empty ecological niches and the response by adapting lineages to occupy them, respectively, drive patterns of phenotypic and lineage diversification. Adaptive radiations driven by 'ecological opportunity' are well established in island systems; it is less clear if ecological opportunity influences continent-wide diversification. We use Neotropical cichlid fishes to test if variation in rates of functional evolution is consistent with changing ecological opportunity. Across a functional morphological axis associated with ram-suction feeding traits, evolutionary rates declined through time as lineages diversified in South America. Evolutionary rates of ram-suction functional morphology also appear to have accelerated as cichlids colonized Central America and encountered renewed opportunity. Our results suggest that ecological opportunity may play an important role in shaping patterns of morphological diversity of even broadly distributed lineages like Neotropical cichlids. © 2016 The Author(s).
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Mechanisms of rapid sympatric speciation by sex reversal and sexual selection in cichlid fish.
Lande, R; Seehausen, O; van Alphen, J J
2001-01-01
Mechanisms of speciation in cichlid fish were investigated by analyzing population genetic models of sexual selection on sex-determining genes associated with color polymorphisms. The models are based on a combination of laboratory experiments and field observations on the ecology, male and female mating behavior, and inheritance of sex-determination and color polymorphisms. The models explain why sex-reversal genes that change males into females tend to be X-linked and associated with novel colors, using the hypothesis of restricted recombination on the sex chromosomes, as suggested by previous theory on the evolution of recombination. The models reveal multiple pathways for rapid sympatric speciation through the origin of novel color morphs with strong assortative mating that incorporate both sex-reversal and suppressor genes. Despite the lack of geographic isolation or ecological differentiation, the new species coexists with the ancestral species either temporarily or indefinitely. These results may help to explain different patterns and rates of speciation among groups of cichlids, in particular the explosive diversification of rock-dwelling haplochromine cichlids.
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Heritability and intertrait correlations in breeding subpopulations of jack pine
Don E. Riemenschneider
1985-01-01
Twenty breeding populations of jack pine were established in 1979 and 1980 in Minnesota, Wisconsin, and Michigan. Four populations were index populations and were each established at 4 locations by research cooperators. Sixteen populations were applied breeding populations and were established at single locations by public and private cooperators. Combined analysis of...
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Birnie, Andrew K; Taylor, Jack H; Cavanaugh, Jon; French, Jeffrey A
2013-12-01
Variation in the early postnatal social environment can have lasting effects on hypothalamic-pituitary-adrenal (HPA) axis stress responses. Both rats and macaque monkeys subjected to low quality or abusive maternal care during the early postnatal period have more pronounced HPA responses to environmental stressors throughout development and into adulthood compared to animals reared in higher quality early maternal environments. However, little is known about the relative contributions to HPA stress response styles in developing offspring in species in which offspring care is routinely provided by group members other than the mother, such as in cooperatively breeding mammals. Marmoset monkeys exhibit cooperative offspring rearing, with fathers and older siblings providing care in addition to that provided by the mother. We evaluated the effects of early maternal, paternal, and older sibling care on HPA responses to social separation across development in captive white-faced marmoset offspring (Callithrix geoffroyi). We monitored offspring care by mothers, fathers, and older siblings in marmosets for the first 60 days of life. Later in development, each marmoset experienced three standardized social separation/novelty exposure stressors at 6, 12, and 18 months of age. During separation, we collected urine samples and analyzed them via enzyme immunoassay for cortisol levels. Infants that received higher rates of rejections from the entire family group showed higher cortisol responses to social separation. This relationship was found when mothers, fathers, and older siblings, were analyzed separately as well. No differences in cortisol responses were found between offspring that received high and low rates of carrying or high and low rates of licking and grooming by any group member. In the cooperatively breeding marmoset, early social cues from multiple classes of caregivers may influence HPA stress responses throughout the lifespan. Published by Elsevier Ltd.
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Kratochwil, Claudius F; Sefton, Maggie M; Meyer, Axel
2015-02-26
Central American crater lake cichlid fish of the Midas species complex (Amphilophus spp.) are a model system for sympatric speciation and fast ecological diversification and specialization. Midas cichlids have been intensively analyzed from an ecological and morphological perspective. Genomic resources such as transcriptomic and genomic data sets, and a high-quality draft genome are available now. Many ecologically relevant species-specific traits and differences such as pigmentation and cranial morphology arise during development. Detailed descriptions of the early development of the Midas cichlid in particular, will help to investigate the ontogeny of species differences and adaptations. We describe the embryonic and larval development of the crater lake cichlid, Amphilophus xiloaensis, until seven days after fertilization. Similar to previous studies on teleost development, we describe six periods of embryogenesis - the zygote, cleavage, blastula, gastrula, segmentation, and post-hatching period. Furthermore, we define homologous stages to well-described teleost models such as medaka and zebrafish, as well as other cichlid species such as the Nile tilapia and the South American cichlid Cichlasoma dimerus. Key morphological differences between the embryos of Midas cichlids and other teleosts are highlighted and discussed, including the presence of adhesive glands and different early chromatophore patterns, as well as variation in developmental timing. The developmental staging of the Midas cichlid will aid researchers in the comparative investigation of teleost ontogenies. It will facilitate comparative developmental biological studies of Neotropical and African cichlid fish in particular. In the past, the species flocks of the African Great Lakes have received the most attention from researchers, but some lineages of the 300-400 species of Central American lakes are fascinating model systems for adaptive radiation and rapid phenotypic evolution. The availability
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Recknagel, Hans; Elmer, Kathryn R; Meyer, Axel
2013-01-01
Cichlid fishes are an excellent model system for studying speciation and the formation of adaptive radiations because of their tremendous species richness and astonishing phenotypic diversity. Most research has focused on African rift lake fishes, although Neotropical cichlid species display much variability as well. Almost one dozen species of the Midas cichlid species complex (Amphilophus spp.) have been described so far and have formed repeated adaptive radiations in several Nicaraguan crater lakes. Here we apply double-digest restriction-site associated DNA sequencing to obtain a high-density linkage map of an interspecific cross between the benthic Amphilophus astorquii and the limnetic Amphilophus zaliosus, which are sympatric species endemic to Crater Lake Apoyo, Nicaragua. A total of 755 RAD markers were genotyped in 343 F(2) hybrids. The map resolved 25 linkage groups and spans a total distance of 1427 cM with an average marker spacing distance of 1.95 cM, almost matching the total number of chromosomes (n = 24) in these species. Regions of segregation distortion were identified in five linkage groups. Based on the pedigree of parents to F(2) offspring, we calculated a genome-wide mutation rate of 6.6 × 10(-8) mutations per nucleotide per generation. This genetic map will facilitate the mapping of ecomorphologically relevant adaptive traits in the repeated phenotypes that evolved within the Midas cichlid lineage and, as the first linkage map of a Neotropical cichlid, facilitate comparative genomic analyses between African cichlids, Neotropical cichlids and other teleost fishes.
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The genetic and developmental basis of an exaggerated craniofacial trait in East African cichlids.
Concannon, Moira R; Albertson, R Craig
2015-12-01
The evolution of an exaggerated trait can lead to a novel morphology that allows organisms to exploit new niches. The molecular bases of such phenotypes can reveal insights into the evolution of unique traits. Here, we investigate a rare morphological innovation in modern haplochromine cichlids, a flap of fibrous tissue that causes a pronounced projection of the snout, which is limited to a single genus (Labeotropheus) of Lake Malawi cichlids. We compare flap size in our focal species L. fuelleborni (LF) to homologous landmarks in other closely related cichlid species that show a range of ecological overlap with LF, and demonstrate that variation in flap size is discontinuous among Malawi cichlid species. We demonstrate further that flap development in LF begins at early juvenile stages, and scales allometrically with body size. We then used an F2 hybrid mapping population, derived via crossing LF to a close ecological competitor that lacks this trait, Tropheops "red cheek" (TRC), to identify quantitative trait loci (QTL) that underlie flap development. In all, we identified four loci associated with variation in flap size, and for each the LF allele contributed to a larger flap. We next cross-referenced our QTL map with population genomic data, comparing natural populations of LF and TRC, to identify divergent polymorphisms within each QTL interval. Candidate genes for flap development are discussed. Together, these data indicate a relatively simple and tractable genetic basis for this morphological innovation, which is consistent with its apparently sudden and saltatory evolutionary history. J. Exp. Zool. (Mol. Dev. Evol.) 324B: 662-670, 2015. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.
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Fruciano, Carmelo; Franchini, Paolo; Raffini, Francesca; Fan, Shaohua; Meyer, Axel
2016-06-01
Established empirical cases of sympatric speciation are scarce, although there is an increasing consensus that sympatric speciation might be more common than previously thought. Midas cichlid fish are one of the few substantiated cases of sympatric speciation, and they formed repeated radiations in crater lakes. In contrast, in the same environment, such radiation patterns have not been observed in other species of cichlids and other families of fish. We analyze morphological and genetic variation in a cichlid species (Archocentrus centrarchus) that co-inhabits several crater lakes with the Midas species complex. In particular, we analyze variation in body and pharyngeal jaw shape (two ecologically important traits in sympatrically divergent Midas cichlids) and relate that to genetic variation in mitochondrial control region and microsatellites. Using these four datasets, we analyze variation between and within two Nicaraguan lakes: a crater lake where multiple Midas cichlids have been described and a lake where the source population lives. We do not observe any within-lake clustering consistent across morphological traits and genetic markers, suggesting the absence of sympatric divergence in A. centrarchus. Genetic differentiation between lakes was low and morphological divergence absent. Such morphological similarity between lakes is found not only in average morphology, but also when analyzing covariation between traits and degree of morphospace occupation. A combined analysis of the mitochondrial control region in A. centrarchus and Midas cichlids suggests that a difference between lineages in the timing of crater lake colonization cannot be invoked as an explanation for the difference in their levels of diversification. In light of our results, A. centrarchus represents the ideal candidate to study the genomic differences between these two lineages that might explain why some lineages are more likely to speciate and diverge in sympatry than others.
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Kesler, D.C.; Haig, S.M.
2007-01-01
We investigated territoriality, prospecting, and dispersal behavior in cooperatively breeding Pohnpei Micronesian Kingfishers (Todiramphus cinnamominus reichenbachii) throughout the annual cycle using radiotelemetry and color-band resights. Mean home-range size was 6.3 ha and territories were 8.1 ha. Within territories, Micronesian Kingfishers shared 63% of their home-range space with coterritorial occupants, and 3% was shared with extraterritorial conspecifics. Birds on cooperative territories had larger home ranges that overlapped more with coterritory occupants' home ranges than birds in pair-held territories. Despite evidence suggesting that resources necessary for survival and reproduction occurred on each territory, Micronesian Kingfishers of all age and sex classes made extraterritorial prospecting movements. Prospecting was rare; it comprised only 4.3% of our observations. When birds departed on forays, they were gone for ∼1.9 h and returned to home territories before sunset. Prospecting by dominant birds was temporally correlated with courtship and nest initiation, and birds were observed at neighboring nest sites with opposite-sex conspecifics during the period when females were available for fertilization. Juveniles and helpers prospected throughout the year and made repeated homesteading movements to dispersal destinations before dispersing. Mean dispersal distance for radiomarked individuals was 849 m. Results suggest that prospecting in Micronesian Kingfishers is a complex behavior that provides information for dispersal decisions and familiarity with dispersal destinations. Additionally, extraterritorial movements may provide covert opportunities for reproduction, which have potential to profoundly influence the distribution of fitness among helper and dominant Micronesian Kingfishers.
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Geiger, Matthias F; McCrary, Jeffrey K; Schliewen, Ulrich K
2010-09-01
Nicaraguan Midas cichlids from crater lakes have recently attracted attention as potential model systems for speciation research, but no attempt has been made to comprehensively reconstruct phylogenetic relationships of this highly diverse and recently evolved species complex. We present a first AFLP (2793 loci) and mtDNA based phylogenetic hypothesis including all described and several undescribed species from six crater lakes (Apoyeque, Apoyo, Asososca Leon, Masaya, Tiscapa and Xiloá), the two great Lakes Managua and Nicaragua and the San Juan River. Our analyses demonstrate that the relationships between the Midas cichlid members are complex, and that phylogenetic information from different markers and methods do not always yield congruent results. Nevertheless, monophyly support for crater lake assemblages from Lakes Apoyeque, Apoyo, A. Leon is high as compared to those from L. Xiloá indicating occurrence of sympatric speciation. Further, we demonstrate that a 'three species' concept for the Midas cichlid complex is inapplicable and consequently that an individualized and voucher based approach in speciation research of the Midas cichlid complex is necessary at least as long as there is no comprehensive revision of the species complex available. Copyright 2010 Elsevier Inc. All rights reserved.
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A novel molecular marker for the study of Neotropical cichlid phylogeny.
Fabrin, T M C; Gasques, L S; Prioli, S M A P; Prioli, A J
2015-12-22
The use of molecular markers has contributed to phylogeny and to the reconstruction of species' evolutionary history. Each region of the genome has different evolution rates, which may or may not identify phylogenetic signal at different levels. Therefore, it is important to assess new molecular markers that can be used for phylogenetic reconstruction. Regions that may be associated with species characteristics and are subject to selective pressure, such as opsin genes, which encode proteins related to the visual system and are widely expressed by Cichlidae family members, are interesting. Our aim was to identify a new nuclear molecular marker that could establish the phylogeny of Neotropical cichlids and is potentially correlated with the visual system. We used Bayesian inference and maximum likelihood analysis to support the use of the nuclear opsin LWS gene in the phylogeny of eight Neotropical cichlid species. Their use concatenated to the mitochondrial gene COI was also tested. The LWS gene fragment comprised the exon 2-4 region, including the introns. The LWS gene provided good support for both analyses up to the genus level, distinguishing the studied species, and when concatenated to the COI gene, there was a good support up to the species level. Another benefit of utilizing this region, is that some polymorphisms are associated with changes in spectral properties of the LWS opsin protein, which constitutes the visual pigment that absorbs red light. Thus, utilization of this gene as a molecular marker to study the phylogeny of Neotropical cichlids is promising.
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Kratochwil, Claudius F; Sefton, Maggie M; Liang, Yipeng; Meyer, Axel
2017-11-23
The Midas cichlid species complex (Amphilophus spp.) is widely known among evolutionary biologists as a model system for sympatric speciation and adaptive phenotypic divergence within extremely short periods of time (a few hundred generations). The repeated parallel evolution of adaptive phenotypes in this radiation, combined with their near genetic identity, makes them an excellent model for studying phenotypic diversification. While many ecological and evolutionary studies have been performed on Midas cichlids, the molecular basis of specific phenotypes, particularly adaptations, and their underlying coding and cis-regulatory changes have not yet been studied thoroughly. For the first time in any New World cichlid, we use Tol2 transposon-mediated transgenesis in the Midas cichlid (Amphilophus citrinellus). By adapting existing microinjection protocols, we established an effective protocol for transgenesis in Midas cichlids. Embryos were injected with a Tol2 plasmid construct that drives enhanced green fluorescent protein (eGFP) expression under the control of the ubiquitin promoter. The transgene was successfully integrated into the germline, driving strong ubiquitous expression of eGFP in the first transgenic Midas cichlid line. Additionally, we show transient expression of two further transgenic constructs, ubiquitin::tdTomato and mitfa::eGFP. Transgenesis in Midas cichlids will facilitate further investigation of the genetic basis of species-specific traits, many of which are adaptations. Transgenesis is a versatile tool not only for studying regulatory elements such as promoters and enhancers, but also for testing gene function through overexpression of allelic gene variants. As such, it is an important first step in establishing the Midas cichlid as a powerful model for studying adaptive coding and non-coding changes in an ecological and evolutionary context.
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Directory of Open Access Journals (Sweden)
Maarten Van Steenberge
Full Text Available The unparalleled biodiversity of Lake Tanganyika (Africa has fascinated biologists for over a century; its unique cichlid communities are a preferred model for evolutionary research. Although species delineation is, in most cases, relatively straightforward, higher-order classifications were shown not to agree with monophyletic groups. Here, traditional morphological methods meet their limitations. A typical example are the tropheine cichlids currently belonging to Simochromis and Pseudosimochromis. The affiliations of these widespread and abundant cichlids are poorly understood. Molecular work suggested that genus and species boundaries should be revised. Moreover, previous morphological results indicated that intraspecific variation should be considered to delineate species in Lake Tanganyika cichlids. We review the genera Simochromis and Pseudosimochromis using an integrative approach. Besides a morphometric study and a barcoding approach, monogenean Cichlidogyrus (Platyhelminthes: Ancyrocephalidae gill parasites, often highly species-specific, are used as complementary markers. Six new species are described. Cichlidogyrus raeymaekersi sp. nov., C. muterezii sp. nov. and C. banyankimbonai sp. nov. infect S. diagramma. Cichlidogyrus georgesmertensi sp. nov. was found on S. babaulti and S. pleurospilus, C. franswittei sp. nov. on both S. marginatus and P. curvifrons and C. frankwillemsi sp. nov. only on P. curvifrons. As relatedness between Cichlidogyrus species usually reflects relatedness between hosts, we considered Simochromis monotypic because the three Cichlidogyrus species found on S. diagramma belonged to a different morphotype than those found on the other Simochromis. The transfer of S. babaulti, S. marginatus, S. pleurospilus and S. margaretae to Pseudosimochromis was justified by the similarity of their Cichlidogyrus fauna and the intermediate morphology of S. margaretae. Finally parasite data also supported the synonymy between S
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Aggression and welfare in a common aquarium fish, the Midas cichlid.
Oldfield, Ronald G
2011-01-01
Many species of fishes are aggressive when placed in small aquaria. Aggression can negatively affect the welfare of those individuals toward whom it is directed. Animals may behave aggressively in order to defend resources such as food, shelter, mates, and offspring. The decision to defend depends on the distribution of resources and on ecological factors such as number of competitors, amount of available space, and amount of habitat complexity. This study tested the effects of these factors on aggression in a common aquarium fish, the Midas cichlid (Amphilophus citrinellus). The study found that time spent behaving aggressively was not associated with small-scale differences in group size or available space. Aggression was significantly lower in a large aquarium with a complex habitat. Aquaria of sizes typically used in the companion animal (pet) hobby did not provide optimal welfare for cichlids housed with aggressive conspecifics. The public should be aware that this and similar species require larger aquaria with complex habitat, which elicit more natural behavior.
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Directory of Open Access Journals (Sweden)
Michael J. Pauers
2016-02-01
Full Text Available For evolutionary ecologists, the holy grail of visual ecology is to establish an unambiguous link between photoreceptor sensitivity, the spectral environment, and the perception of specific visual stimuli (e.g., mates, food, predators, etc.. Due to the bright nuptial colors of the males, and the role female mate choice plays in their evolution, the haplochromine cichlid fishes of the African great lakes are favorite research subjects for such investigations. Despite this attention, current evidence is equivocal; while distinct correlations among photoreceptor sensitivity, photic environment, and male coloration exist in Lake Victorian haplochromines, attempts to find such correlations in Lake Malawian cichlids have failed. Lake Malawi haplochromines have a wide variability in their short-wavelength-sensitive photoreceptors, especially compared to their mid- and long-wavelength-sensitive photoreceptors; these cichlids also vary in the degree to which they express one of three basic color patterns (vertical bars, horizontal stripes, and solid patches of colors, each of which is likely used in a different form of communication. Thus, we hypothesize that, in these fishes, spectral sensitivity and color pattern have evolved in a correlated fashion to maximize visual communication; specifically, ultraviolet sensitivity should be found in vertically-barred species to promote ‘private’ communication, while striped species should be less likely to have ultraviolet sensitivity, since their color pattern carries ‘public’ information. Using phylogenetic independent contrasts, we found that barred species had strong sensitivity to ultraviolet wavelengths, but that striped species typically lacked sensitivity to ultraviolet light. Further, the only variable, even when environmental variables were simultaneously considered, that could predict ultraviolet sensitivity was color pattern. We also found that, using models of correlated evolution, color
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Harrison, Elizabeth; Trexler, Joel C.; Collins, Timothy M.; Vazquez-Domínguez, Ella; Razo-Mendivil, Ulises; Matamoros, Wilfredo A.; Barrientos, Christian
2014-01-01
The number and diversity of source populations may influence the genetic diversity of newly introduced populations and affect the likelihood of their establishment and spread. We used the cytochrome b mitochondrial gene and nuclear microsatellite loci to identify the sources of a successful invader in southern Florida, USA, Cichlasoma urophthalmus (Mayan cichlid). Our cytochrome b data supported an introduction from Guatemala, while our microsatellite data suggested movement of Mayan Cichlids...
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Rapid sympatric ecological differentiation of crater lake cichlid fishes within historic times
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Harrod Chris
2010-05-01
Full Text Available Abstract Background After a volcano erupts, a lake may form in the cooled crater and become an isolated aquatic ecosystem. This makes fishes in crater lakes informative for understanding sympatric evolution and ecological diversification in barren environments. From a geological and limnological perspective, such research offers insight about the process of crater lake ecosystem establishment and speciation. In the present study we use genetic and coalescence approaches to infer the colonization history of Midas cichlid fishes (Amphilophus cf. citrinellus that inhabit a very young crater lake in Nicaragua-the ca. 1800 year-old Lake Apoyeque. This lake holds two sympatric, endemic morphs of Midas cichlid: one with large, hypertrophied lips (~20% of the total population and another with thin lips. Here we test the associated ecological, morphological and genetic diversification of these two morphs and their potential to represent incipient speciation. Results Gene coalescence analyses [11 microsatellite loci and mitochondrial DNA (mtDNA sequences] suggest that crater lake Apoyeque was colonized in a single event from the large neighbouring great lake Managua only about 100 years ago. This founding in historic times is also reflected in the extremely low nuclear and mitochondrial genetic diversity in Apoyeque. We found that sympatric adult thin- and thick-lipped fishes occupy distinct ecological trophic niches. Diet, body shape, head width, pharyngeal jaw size and shape and stable isotope values all differ significantly between the two lip-morphs. The eco-morphological features pharyngeal jaw shape, body shape, stomach contents and stable isotopes (δ15N all show a bimodal distribution of traits, which is compatible with the expectations of an initial stage of ecological speciation under disruptive selection. Genetic differentiation between the thin- and thick-lipped population is weak at mtDNA sequence (FST = 0.018 and absent at nuclear
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Directory of Open Access Journals (Sweden)
Stiassny Melanie LJ
2010-05-01
Full Text Available Abstract Background It is hypothesized that one of the mechanisms promoting diversification in cichlid fishes in the African Great Lakes has been the well-documented pattern of philopatry along shoreline habitats leading to high levels of genetic isolation among populations. However lake habitats are not the only centers of cichlid biodiversity - certain African rivers also contain large numbers of narrowly endemic species. Patterns of isolation and divergence in these systems have tended to be overlooked and are not well understood. Results We examined genetic and morphological divergence among populations of two narrowly endemic cichlid species, Teleogramma depressum and Lamprologus tigripictilis, from a 100 km stretch of the lower Congo River using both nDNA microsatellites and mtDNA markers along with coordinate-based morphological techniques. In L. tigripictilis, the strongest genetic break was concordant with measurable phenotypic divergence but no morphological disjunction was detected for T. depressum despite significant differentiation at mtDNA and nDNA microsatellite markers. Conclusions The genetic markers revealed patterns of philopatry and estimates of genetic isolation that are among the highest reported for any African cichlid species over a comparable geographic scale. We hypothesize that the high levels of philopatry observed are generated and maintained by the extreme hydrology of the lower Congo River.
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Directory of Open Access Journals (Sweden)
Elizabeth Harrison
Full Text Available The number and diversity of source populations may influence the genetic diversity of newly introduced populations and affect the likelihood of their establishment and spread. We used the cytochrome b mitochondrial gene and nuclear microsatellite loci to identify the sources of a successful invader in southern Florida, USA, Cichlasoma urophthalmus (Mayan cichlid. Our cytochrome b data supported an introduction from Guatemala, while our microsatellite data suggested movement of Mayan Cichlids from the upper Yucatán Peninsula to Guatemala and introductions from Guatemala and Belize to Florida. The mismatch between mitochondrial and nuclear genomes suggests admixture of a female lineage from Guatemala, where all individuals were fixed for the mitochondrial haplotype found in the introduced population, and a more diverse but also relatively small number of individuals from Belize. The Florida cytochrome b haplotype appears to be absent from Belize (0 out of 136 fish screened from Belize had this haplotype. Genetic structure within the Florida population was minimal, indicating a panmictic population, while Mexican and Central American samples displayed more genetic subdivision. Individuals from the Upper Yucatán Peninsula and the Petén region of Guatemala were more genetically similar to each other than to fish from nearby sites and movement of Mayan Cichlids between these regions occurred thousands of generations ago, suggestive of pre-Columbian human transportation of Mayan Cichlids through this region. Mayan Cichlids present a rare example of cytonuclear disequilibrium and reduced genetic diversity in the introduced population that persists more than 30 years (at least 7-8 generations after introduction. We suggest that hybridization occurred in ornamental fish farms in Florida and may contribute their establishment in the novel habitat. Hybridization prior to release may contribute to other successful invasions.
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Harrison, Elizabeth; Trexler, Joel C; Collins, Timothy M; Vazquez-Domínguez, Ella; Razo-Mendivil, Ulises; Matamoros, Wilfredo A; Barrientos, Christian
2014-01-01
The number and diversity of source populations may influence the genetic diversity of newly introduced populations and affect the likelihood of their establishment and spread. We used the cytochrome b mitochondrial gene and nuclear microsatellite loci to identify the sources of a successful invader in southern Florida, USA, Cichlasoma urophthalmus (Mayan cichlid). Our cytochrome b data supported an introduction from Guatemala, while our microsatellite data suggested movement of Mayan Cichlids from the upper Yucatán Peninsula to Guatemala and introductions from Guatemala and Belize to Florida. The mismatch between mitochondrial and nuclear genomes suggests admixture of a female lineage from Guatemala, where all individuals were fixed for the mitochondrial haplotype found in the introduced population, and a more diverse but also relatively small number of individuals from Belize. The Florida cytochrome b haplotype appears to be absent from Belize (0 out of 136 fish screened from Belize had this haplotype). Genetic structure within the Florida population was minimal, indicating a panmictic population, while Mexican and Central American samples displayed more genetic subdivision. Individuals from the Upper Yucatán Peninsula and the Petén region of Guatemala were more genetically similar to each other than to fish from nearby sites and movement of Mayan Cichlids between these regions occurred thousands of generations ago, suggestive of pre-Columbian human transportation of Mayan Cichlids through this region. Mayan Cichlids present a rare example of cytonuclear disequilibrium and reduced genetic diversity in the introduced population that persists more than 30 years (at least 7-8 generations) after introduction. We suggest that hybridization occurred in ornamental fish farms in Florida and may contribute their establishment in the novel habitat. Hybridization prior to release may contribute to other successful invasions.
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Divergent mating preferences and nuptial coloration in sibling species of cichlid fish
Sluijs, Inke van der
2008-01-01
Mate choice by female cichlid fish from Lake Victoria plays an important role in speciation and the maintenance of species. Females are expected to select against males that are intermediate in their phenotype during the process of speciation driven by sexual selection. To test this, we hybridized
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Effects of selection for cooperation and attention in dogs
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Miklósi Ádám
2009-07-01
Full Text Available Abstract Background It has been suggested that the functional similarities in the socio-cognitive behaviour of dogs and humans emerged as a consequence of comparable environmental selection pressures. Here we use a novel approach to account for the facilitating effect of domestication in dogs and reveal that selection for two factors under genetic influence (visual cooperation and focused attention may have led independently to increased comprehension of human communicational cues. Method In Study 1, we observed the performance of three groups of dogs in utilizing the human pointing gesture in a two-way object choice test. We compared breeds selected to work while visually separated from human partners (N = 30, 21 breeds, clustered as independent worker group, with those selected to work in close cooperation and continuous visual contact with human partners (N = 30, 22 breeds, clustered as cooperative worker group, and with a group of mongrels (N = 30. Secondly, it has been reported that, in dogs, selective breeding to produce an abnormal shortening of the skull is associated with a more pronounced area centralis (location of greatest visual acuity. In Study 2, breeds with high cephalic index and more frontally placed eyes (brachycephalic breeds, N = 25, 14 breeds were compared with breeds with low cephalic index and laterally placed eyes (dolichocephalic breeds, N = 25, 14 breeds. Results In Study 1, cooperative workers were significantly more successful in utilizing the human pointing gesture than both the independent workers and the mongrels. In study 2, we found that brachycephalic dogs performed significantly better than dolichocephalic breeds. Discussion After controlling for environmental factors, we have provided evidence that at least two independent phenotypic traits with certain genetic variability affect the ability of dogs to rely on human visual cues. This finding should caution researchers against making simple generalizations
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Härer, Andreas; Torres-Dowdall, Julián; Meyer, Axel
2017-10-01
Colonization of novel habitats is typically challenging to organisms. In the initial stage after colonization, approximation to fitness optima in the new environment can occur by selection acting on standing genetic variation, modification of developmental patterns or phenotypic plasticity. Midas cichlids have recently colonized crater Lake Apoyo from great Lake Nicaragua. The photic environment of crater Lake Apoyo is shifted towards shorter wavelengths compared to great Lake Nicaragua and Midas cichlids from both lakes differ in visual sensitivity. We investigated the contribution of ontogeny and phenotypic plasticity in shaping the visual system of Midas cichlids after colonizing this novel photic environment. To this end, we measured cone opsin expression both during development and after experimental exposure to different light treatments. Midas cichlids from both lakes undergo ontogenetic changes in cone opsin expression, but visual sensitivity is consistently shifted towards shorter wavelengths in crater lake fish, which leads to a paedomorphic retention of their visual phenotype. This shift might be mediated by lower levels of thyroid hormone in crater lake Midas cichlids (measured indirectly as dio2 and dio3 gene expression). Exposing fish to different light treatments revealed that cone opsin expression is phenotypically plastic in both species during early development, with short and long wavelength light slowing or accelerating ontogenetic changes, respectively. Notably, this plastic response was maintained into adulthood only in the derived crater lake Midas cichlids. We conclude that the rapid evolution of Midas cichlids' visual system after colonizing crater Lake Apoyo was mediated by a shift in visual sensitivity during ontogeny and was further aided by phenotypic plasticity during development. © 2017 John Wiley & Sons Ltd.
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Parental Investment and sexual immune dimorphism in cichlids ans syngnathids
Keller, Isabel Salome
2017-01-01
I investigated how the interrelationship between parental investment and sexual immune dimorphism shape the evolution of parental care strategies within the cichlids and syngnathids. To understand why parental investment is displayed in such diversity in the animal kingdom, I assessed evolutionary and provisioning costs of parental investment in male pregnancy, biparental and maternal mouthbrooding. Additionally, to address the importance of parental investment, I tested for maternal effects ...
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Tianshuishi space breeding current situation and developing trend
International Nuclear Information System (INIS)
Wang Fuquan; Song Jianrong; Zhang Zhongping; Guo Zhenfang
2012-01-01
Tianshuishi is located in Xi'an to lanzhou among two big cities, the five space launch, has vegetables, food, grasses, flowers, rape, melon and fruit, Chinese traditional medicine, amount of 8 categories of crops, such as the 22 new material after carrying the ground breeding work. Only vegetables on identified 23 aerospace new varieties. After ten years of space breeding, summarizes the present situation of Tianshuishi space breeding, development experience, characteristic, trends, and puts forward the development space breeding Tianshuishi organization and breeding of talent from the matching policy and grow up incentive mechanism, strengthen the cooperation and all over the country, establishing fiscal policy support from the aspects such as advice. (authors)
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Dijkstra, Peter D.; Verzijden, Machteld N.; Groothuis, Ton G. G.; Hofmann, Hans A.
The diverse cichlid species flocks of the East African lakes provide a classical example of adaptive radiation. Territorial aggression is thought to influence the evolution of phenotypic diversity in this system. Most vertebrates mount hormonal (androgen, glucocorticoid) responses to a territorial
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Jiménez-García, María Isabel; Suárez-Morales, Eduardo
2017-01-01
During a parasitological survey of the ichthyofauna of Lake Catemaco, a freshwater system in the Mexican State of Veracruz, the widespread copepod Ergasilus arthrosis Roberts, 1969 was recovered from two cichlid teleosts, Mayaheros urophthalmus (Günther) and Oreochromis sp. This is the first confirmed record of this copepod species outside of the United States and from Mexico; its finding as a parasite of cichlids represents an expansion of the known host range for this copepod. The local prevalence and intensity of infection of E. arthrosis was highest in M. urophthalmus. The infection prevalence of E. arthrosis on M. urophthalmus (60%) was higher than that known for other ergasilids on cichlids. Ergasilus arthrosis can be distinguished from its closest congener E. lizae Krøyer, 1863 by the morphometry of the antennary segments, the ventral ornamentation of the thoracic sclerites and by details of the antennulary setation, but also by its habitat and host preferences. Taxonomic illustrations and morphological details of the specimens examined are also provided together with comments on the variability of this species.
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William G. R. Crampton
Full Text Available The discus fishes of the genus Symphysodon are popular ornamental cichlids that occur in floodplain lakes and flooded forests of the lowland Amazon Basin. These habitats are characterized by extreme seasonal fluctuations in the availability of food, shelter and dissolved oxygen, and also the densities of predators and parasites. Most aspects of discus biology are influenced by these fluctuating conditions. This paper reports an autoecological study of the western Amazonian discus S. haraldi (until recently classified as S. aequifasciatus. This species feeds predominantly on algal periphyton, fine organic detritus, plant matter, and small aquatic invertebrates. At high water it forages alone or in small groups in flooded forests. At low water it forms large aggregations in fallen tree crowns along lake margins. Breeding occurs at the beginning of the flood season, ensuring that the progeny are well grown before the next low water period. Symphysodon haraldi is an iteroparous partial spawner, reaches reproductive maturity within a year, and undertakes parental care of its eggs and larvae. The timing of spawning events, and/or the rate of brood survival, may be influenced by fluctuations in the flood level, resulting in a non-unimodal distribution of size classes for the subsequent 1+ cohort.
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Lin, Susan M; Nieves-Puigdoller, Katherine; Brown, Alexandria C; McGraw, Kevin J; Clotfelter, Ethan D
2010-01-01
Many animals use carotenoid pigments derived from their diet for coloration and immunity. The carotenoid trade-off hypothesis predicts that, under conditions of carotenoid scarcity, individuals may be forced to allocate limited carotenoids to either coloration or immunity. In polychromatic species, the pattern of allocation may differ among individuals. We tested the carotenoid trade-off hypothesis in the Midas cichlid, Amphilophus citrinellus, a species with two ontogenetic color morphs, barred and gold, the latter of which is the result of carotenoid expression. We performed a diet-supplementation experiment in which cichlids of both color morphs were assigned to one of two diet treatments that differed only in carotenoid content (beta-carotene, lutein, and zeaxanthin). We measured integument color using spectrometry, quantified carotenoid concentrations in tissue and plasma, and assessed innate immunity using lysozyme activity and alternative complement pathway assays. In both color morphs, dietary carotenoid supplementation elevated plasma carotenoid circulation but failed to affect skin coloration. Consistent with observable differences in integument coloration, we found that gold fish sequestered more carotenoids in skin tissue than barred fish, but barred fish had higher concentrations of carotenoids in plasma than gold fish. Neither measure of innate immunity differed between gold and barred fish, or as a function of dietary carotenoid supplementation. Lysozyme activity, but not complement activity, was strongly affected by body condition. Our data show that a diet low in carotenoids is sufficient to maintain both coloration and innate immunity in Midas cichlids. Our data also suggest that the developmental transition from the barred to gold morph is not accompanied by a decrease in innate immunity in this species.
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Willis, Stuart; Watkins, Crystal; Honeycutt, Rodney L.; Winemiller, Kirk O.
2014-01-01
Understanding of relationships between morphology and ecological performance can help to reveal how natural selection drives biological diversification. We investigate relationships between feeding behavior, foraging performance and morphology within a diverse group of teleost fishes, and examine the extent to which associations can be explained by evolutionary relatedness. Morphological adaptation associated with sediment sifting was examined using a phylogenetic linear discriminant analysis on a set of ecomorphological traits from 27 species of Neotropical cichlids. For most sifting taxa, feeding behavior could be effectively predicted by a linear discriminant function of ecomorphology across multiple clades of sediment sifters, and this pattern could not be explained by shared evolutionary history alone. Additionally, we tested foraging efficiency in seven Neotropical cichlid species, five of which are specialized benthic feeders with differing head morphology. Efficiency was evaluated based on the degree to which invertebrate prey could be retrieved at different depths of sediment. Feeding performance was compared both with respect to feeding mode and species using a phylogenetic ANCOVA, with substrate depth as a covariate. Benthic foraging performance was constant across sediment depths in non-sifters but declined with depth in sifters. The non-sifting Hypsophrys used sweeping motions of the body and fins to excavate large pits to uncover prey; this tactic was more efficient for consuming deeply buried invertebrates than observed among sediment sifters. Findings indicate that similar feeding performance among sediment-sifting cichlids extracting invertebrate prey from shallow sediment layers reflects constraints associated with functional morphology and, to a lesser extent, phylogeny. PMID:24603485
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Directory of Open Access Journals (Sweden)
Hernán López-Fernández
Full Text Available Understanding of relationships between morphology and ecological performance can help to reveal how natural selection drives biological diversification. We investigate relationships between feeding behavior, foraging performance and morphology within a diverse group of teleost fishes, and examine the extent to which associations can be explained by evolutionary relatedness. Morphological adaptation associated with sediment sifting was examined using a phylogenetic linear discriminant analysis on a set of ecomorphological traits from 27 species of Neotropical cichlids. For most sifting taxa, feeding behavior could be effectively predicted by a linear discriminant function of ecomorphology across multiple clades of sediment sifters, and this pattern could not be explained by shared evolutionary history alone. Additionally, we tested foraging efficiency in seven Neotropical cichlid species, five of which are specialized benthic feeders with differing head morphology. Efficiency was evaluated based on the degree to which invertebrate prey could be retrieved at different depths of sediment. Feeding performance was compared both with respect to feeding mode and species using a phylogenetic ANCOVA, with substrate depth as a covariate. Benthic foraging performance was constant across sediment depths in non-sifters but declined with depth in sifters. The non-sifting Hypsophrys used sweeping motions of the body and fins to excavate large pits to uncover prey; this tactic was more efficient for consuming deeply buried invertebrates than observed among sediment sifters. Findings indicate that similar feeding performance among sediment-sifting cichlids extracting invertebrate prey from shallow sediment layers reflects constraints associated with functional morphology and, to a lesser extent, phylogeny.
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López-Fernández, Hernán; Arbour, Jessica; Willis, Stuart; Watkins, Crystal; Honeycutt, Rodney L; Winemiller, Kirk O
2014-01-01
Understanding of relationships between morphology and ecological performance can help to reveal how natural selection drives biological diversification. We investigate relationships between feeding behavior, foraging performance and morphology within a diverse group of teleost fishes, and examine the extent to which associations can be explained by evolutionary relatedness. Morphological adaptation associated with sediment sifting was examined using a phylogenetic linear discriminant analysis on a set of ecomorphological traits from 27 species of Neotropical cichlids. For most sifting taxa, feeding behavior could be effectively predicted by a linear discriminant function of ecomorphology across multiple clades of sediment sifters, and this pattern could not be explained by shared evolutionary history alone. Additionally, we tested foraging efficiency in seven Neotropical cichlid species, five of which are specialized benthic feeders with differing head morphology. Efficiency was evaluated based on the degree to which invertebrate prey could be retrieved at different depths of sediment. Feeding performance was compared both with respect to feeding mode and species using a phylogenetic ANCOVA, with substrate depth as a covariate. Benthic foraging performance was constant across sediment depths in non-sifters but declined with depth in sifters. The non-sifting Hypsophrys used sweeping motions of the body and fins to excavate large pits to uncover prey; this tactic was more efficient for consuming deeply buried invertebrates than observed among sediment sifters. Findings indicate that similar feeding performance among sediment-sifting cichlids extracting invertebrate prey from shallow sediment layers reflects constraints associated with functional morphology and, to a lesser extent, phylogeny.
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Meade, Jessica; Nam, Ki-Baek; Beckerman, Andrew P; Hatchwell, Ben J
2010-05-01
1. Helpers that invest energy in provisioning the offspring of related individuals stand to gain indirect fitness benefits from doing so. First, if the helper's effort is additional to that of the parents (additive) the productivity of the current breeding attempt can be increased. Secondly, if the parents reduce their workload (compensation) this can result in future indirect fitness gains to the helper via increased breeder survival; termed 'load-lightening'. 2. Long-tailed tits (Aegithalos caudatus) have a cooperative breeding system in which helpers assist kin and parents exhibit both additive and compensatory reactions in the presence of helpers. Offspring from helped nests are heavier and more likely to recruit into the breeding population, thus helpers gain indirect fitness benefits from increasing the productivity of the current breeding attempt. Despite breeders' reduction of feeding effort in the presence of helpers, previous investigations found no subsequent increase in breeder survival. 3. The aim of this study was to test the hypothesis that load-lightening resulted in indirect fitness benefits for helpers. We used data from a 14-year study to investigate the provisioning rate, survival and future fecundity of male and female long-tailed tits that did and did not receive help at the nest. 4. We found an asymmetrical response to the presence of helpers at large brood sizes. Males reduced their feeding rate more than females, and this differential response was reflected in a significant increase in male survival when provisioning large broods assisted by helpers. We found no evidence of any increase in future fecundity for helped breeders. 5. The finding that males reduce their provisioning rate in the presence of helpers (at large brood sizes) to a greater degree than females, and that this is reflected in an increase in survival rate for males only, implies that the survival increase is caused by the reduction in work-rate rather than a non
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Nico, Leo G.; Beamish, William H.; Musikasinthorn, Prachya
2007-01-01
We report on the occurrence and possible establishment of a non-native cichlid fish in a brackish-water system in the lower Chao Phraya River delta region, Thailand. Although, the possibility of some degree of introgressive hybridization can not be ruled out, Thailand specimens agree best with Mayan Cichlid “Cichlasoma” urophthalmus (Günther 1862). Our collections represent the first records of this New World, highly-invasive, euryhaline fish from Thailand and coincides with recent collections from Singapore. Positive identification of specimens as “C.” urophthalmus requires caution due to the diversity of the Cichlidae (>1,300 species), widespread introduction of many family members, variation within species, extensive interspecific overlap in characters, and proliferation of artificial cichlid hybrids (e.g., Flowerhorns). We first became aware of the Thailand population in 2005 when “C.” urophthalmus began appearing in the catches of local fishermen. We visited the site in November 2006 and obtained and examined voucher specimens. The abundance and wide size range of juveniles and adults in local ponds and an adjacent canal is evidence of natural reproduction. Because water bodies throughout the Chao Phraya delta are interconnected and subject to flooding, it is likely that “C.” urophthalmus is already established and is dispersing, but surveys and monitoring are needed to determine their exact geographic range. The Thailand population is compared to “C.” urophthalmus introduced into Florida (USA). Based on what is known about Florida “C.” urophthalmus, it is predicted that this cichlid will further invade coastal and inland waters in Thailand and elsewhere in Southeast Asia. This cichlid has a long history in the aquarium trade in Europe. However, there are no records from the wild in European waters and, because of the colder climate, the possibility of establishment in that region is relatively low.
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The increased risk of predation enhances cooperation
Krams, Indrikis; Bērziņš, Arnis; Krama, Tatjana; Wheatcroft, David; Igaune, Kristīne; Rantala, Markus J.
2010-01-01
Theory predicts that animals in adverse conditions can decrease individual risks and increase long-term benefits by cooperating with neighbours. However, some empirical studies suggest that animals often focus on short-term benefits, which can reduce the likelihood that they will cooperate with others. In this experimental study, we tested between these two alternatives by evaluating whether increased predation risk (as a correlate of environmental adversity) enhances or diminishes the occurrence of cooperation in mobbing, a common anti-predator behaviour, among breeding pied flycatchers Ficedula hypoleuca. We tested whether birds would join their mobbing neighbours more often and harass a stuffed predator placed near their neighbours' nests more intensely in areas with a higher perceived risk of predation. Our results show that birds attended mobs initiated by their neighbours more often, approached the stuffed predator significantly more closely, and mobbed it at a higher intensity in areas where the perceived risk of predation was experimentally increased. In such high-risk areas, birds also were more often involved in between-pair cooperation. This study demonstrates the positive impact of predation risk on cooperation in breeding songbirds, which might help in explaining the emergence and evolution of cooperation. PMID:19846454
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Vanhove, Maarten P M; Pariselle, Antoine; Van Steenberge, Maarten; Raeymaekers, Joost A M; Hablützel, Pascal I; Gillardin, Céline; Hellemans, Bart; Breman, Floris C; Koblmüller, Stephan; Sturmbauer, Christian; Snoeks, Jos; Volckaert, Filip A M; Huyse, Tine
2015-09-03
The stunning diversity of cichlid fishes has greatly enhanced our understanding of speciation and radiation. Little is known about the evolution of cichlid parasites. Parasites are abundant components of biodiversity, whose diversity typically exceeds that of their hosts. In the first comprehensive phylogenetic parasitological analysis of a vertebrate radiation, we study monogenean parasites infecting tropheine cichlids from Lake Tanganyika. Monogeneans are flatworms usually infecting the body surface and gills of fishes. In contrast to many other parasites, they depend only on a single host species to complete their lifecycle. Our spatially comprehensive combined nuclear-mitochondrial DNA dataset of the parasites covering almost all tropheine host species (N = 18), reveals species-rich parasite assemblages and shows consistent host-specificity. Statistical comparisons of host and parasite phylogenies based on distance and topology-based tests demonstrate significant congruence and suggest that host-switching is rare. Molecular rate evaluation indicates that species of Cichlidogyrus probably diverged synchronically with the initial radiation of the tropheines. They further diversified through within-host speciation into an overlooked species radiation. The unique life history and specialisation of certain parasite groups has profound evolutionary consequences. Hence, evolutionary parasitology adds a new dimension to the study of biodiversity hotspots like Lake Tanganyika.
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TianShuiShi space breeding current situation and developing trend
International Nuclear Information System (INIS)
Wang Fuquan; Song Jianrong; Zhang Zhongping; Guo Zhenfang
2011-01-01
TianShuiShi is located in xian to lanzhou among two big cities, the five space launch, has vegetables, food, grasses, flowers, rape, melon and fruit, Chinese traditional medicine, amount of 8 categories of crops, such as the 22 new material after carrying the ground breeding work. Only vegetables on identified 23 aerospace new varieties. After ten years of space breeding, summarizes the present situation of TianShuiShi space breeding, development experience, characteristic, trends, and puts forward the development space breeding TianShuiShi organization and breeding of talent from the matching policy and grow up incentive mechanism, strengthen the cooperation and all over the country, establishing fiscal policy support from the aspects such as advice. (authors)
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Field evidence for colony size and aseasonality of breeding and in ...
African Journals Online (AJOL)
Ansell's mole-rat, Fukomys anselli, is a cooperatively breeding bathyergid endemic to the Lusaka Province of Zambia. During a 12-month field study involving the capture of 33 colonies of mole-rats, the number of occupants, breeding females and sex ratio within colonies were recorded. While thirty of these social groups ...
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Franchini, Paolo; Fruciano, Carmelo; Frickey, Tancred; Jones, Julia C; Meyer, Axel
2014-01-01
Gut bacterial communities are now known to influence a range of fitness related aspects of organisms. But how different the microbial community is in closely related species, and if these differences can be interpreted as adaptive is still unclear. In this study we compared microbial communities in two sets of closely related sympatric crater lake cichlid fish species pairs that show similar adaptations along the limnetic-benthic axis. The gut microbial community composition differs in the species pair inhabiting the older of two crater lakes. One major difference, relative to other fish, is that in these cichlids that live in hypersaline crater lakes, the microbial community is largely made up of Oceanospirillales (52.28%) which are halotolerant or halophilic bacteria. This analysis opens up further avenues to identify candidate symbiotic or co-evolved bacteria playing a role in adaptation to similar diets and life-styles or even have a role in speciation. Future functional and phylosymbiotic analyses might help to address these issues.
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Directory of Open Access Journals (Sweden)
Kolm Niclas
2009-09-01
Full Text Available Abstract Background The vertebrate brain is composed of several interconnected, functionally distinct structures and much debate has surrounded the basic question of how these structures evolve. On the one hand, according to the 'mosaic evolution hypothesis', because of the elevated metabolic cost of brain tissue, selection is expected to target specific structures mediating the cognitive abilities which are being favored. On the other hand, the 'concerted evolution hypothesis' argues that developmental constraints limit such mosaic evolution and instead the size of the entire brain varies in response to selection on any of its constituent parts. To date, analyses of these hypotheses of brain evolution have been limited to mammals and birds; excluding Actinopterygii, the basal and most diverse class of vertebrates. Using a combination of recently developed phylogenetic multivariate allometry analyses and comparative methods that can identify distinct rates of evolution, even in highly correlated traits, we studied brain structure evolution in a highly variable clade of ray-finned fishes; the Tanganyikan cichlids. Results Total brain size explained 86% of the variance in brain structure volume in cichlids, a lower proportion than what has previously been reported for mammals. Brain structures showed variation in pair-wise allometry suggesting some degree of independence in evolutionary changes in size. This result is supported by variation among structures on the strength of their loadings on the principal size axis of the allometric analysis. The rate of evolution analyses generally supported the results of the multivariate allometry analyses, showing variation among several structures in their evolutionary patterns. The olfactory bulbs and hypothalamus were found to evolve faster than other structures while the dorsal medulla presented the slowest evolutionary rate. Conclusion Our results favor a mosaic model of brain evolution, as certain
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Czech Academy of Sciences Publication Activity Database
Musilová, Zuzana; Říčan, Oldřich; Janko, Karel; Novák, J.
2008-01-01
Roč. 46, - (2008), s. 659-672 ISSN 1055-7903 R&D Projects: GA MŠk LC06073 Grant - others:GA UK(CZ) 182/2004/B-BIO; GA UK(CZ) 139407 Institutional research plan: CEZ:AV0Z50450515 Keywords : molecular phylogeny * Cichlids * south America Subject RIV: EG - Zoology Impact factor: 3.871, year: 2008
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DuVal, Emily H
2013-07-01
Experience improves individual performance in many tasks. Pre-breeding cooperation may provide important experience that improves later success as a breeder, offering one compelling explanation for why some individuals delay reproduction to help others breed (the 'skills hypothesis'). However, confounding effects of age, quality and alternative selective benefits have complicated rigorous tests of this hypothesis. Male lance-tailed manakins perform cooperative courtship displays involving partnerships between unrelated alpha and beta males, and alphas monopolize resulting copulations. Beta males therefore do not receive immediate direct or indirect fitness benefits, but may gain skills during cooperation that increase their later success as an alpha. To date, however, the effect of cooperative experience on later success as a breeder has never been tested in any cooperatively displaying taxon. The effects of prior cooperative experience on reproductive success of alpha lance-tailed manakins were analysed in a mixed model framework using 12 years of information on cooperative experience and annual and lifetime genetic reproductive success for 57 alpha males. Models included previously identified effects of age and alpha tenure. Individual-level random effects controlled for quality differences to test for an independent influence of beta experience on success. Males accumulated up to 5 years of beta experience before becoming alphas, but 42·1% of alphas had no prior beta experience. Betas became alphas later in life, and experienced significantly lower reproductive success in their final year as alpha than males that were never beta, but did not have higher lifetime success or longer alpha tenures. Differences in patterns of annual siring success were best explained by age-dependent patterns of reproductive improvement and senescence among alphas, not beta experience. Cooperative experience does not increase relative breeding success for male lance-tailed manakins
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Correlated evolution of body and fin morphology in the cichlid fishes.
Feilich, Kara L
2016-10-01
Body and fin shapes are chief determinants of swimming performance in fishes. Different configurations of body and fin shapes can suit different locomotor specializations. The success of any configuration is dependent upon the hydrodynamic interactions between body and fins. Despite the importance of body-fin interactions for swimming, there are few data indicating whether body and fin configurations evolve in concert, or whether these structures vary independently. The cichlid fishes are a diverse family whose well-studied phylogenetic relationships make them ideal for the study of macroevolution of ecomorphology. This study measured body, and caudal and median fin morphology from radiographs of 131 cichlid genera, using morphometrics and phylogenetic comparative methods to determine whether these traits exhibit correlated evolution. Partial least squares canonical analysis revealed that body, caudal fin, dorsal fin, and anal fin shapes all exhibited strong correlated evolution consistent with locomotor ecomorphology. Major patterns included the evolution of deep body profiles with long fins, suggestive of maneuvering specialization; and the evolution of narrow, elongate caudal peduncles with concave tails, a combination that characterizes economical cruisers. These results demonstrate that body shape evolution does not occur independently of other traits, but among a suite of other morphological changes that augment locomotor specialization. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.
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Population structure of Pacific Common Eiders breeding in Alaska
Petersen, M.R.; Flint, P.L.
2002-01-01
We used satellite telemetry to study the migration routes and wintering areas of two allopatric breeding populations of Pacific Common Eiders (Somateria mollissima v-nigrum) in Alaska: the Yukon-Kuskokwim Delta, and the western Beaufort Sea coast. Only 6% (2 of 36) of females wintered within the wintering area of the other breeding population. Both breeding populations wintered in the closest available ice-free habitat, perhaps to minimize migratory distance. Two Beaufort Sea females wintered in areas used by Yukon-Kuskokwim Delta females, implying potential gene flow among breeding areas. Yet, we conclude that these two populations are largely geographically isolated throughout the annual cycle and the environmental factors influencing survival and reproduction likely differ between these groups of birds. Thus, regardless of the potential gene flow among breeding populations, we suggest that birds from these two breeding areas should be managed as separate populations. ?? The Cooper Ornithological Society 2002.
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Rehage, Jennifer S.; Dunlop, Katherine L.; Loftus, William F.
2009-01-01
The strong impact of non-native predators in aquatic systems is thought to relate to the evolutionary naiveté of prey. Due to isolation and limited dispersal, this naiveté may be relatively high in freshwater systems. In this study, we tested this notion by examining the antipredator response of native mosquitofish, Gambusia holbrooki, to two non-native predators found in the Everglades, the African jewelfish,Hemichromis letourneuxi, and the Mayan cichlid, Cichlasoma urophthalmus. We manipulated prey naiveté by using two mosquitofish populations that varied in their experience with the recent invader, the African jewelfish, but had similar levels of experience with the longer-established Mayan cichlid. Specifically, we tested these predictions: (1) predator hunting modes differed between the two predators, (2) predation rates would be higher by the novel jewelfish predator, (3) particularly on the naive population living where jewelfish have not invaded yet, (4) antipredator responses would be stronger to Mayan cichlids due to greater experience and weaker and/or ineffective to jewelfish, and (5) especially weakest by the naive population. We assayed prey and predator behavior, and prey mortality in lab aquaria where both predators and prey were free-ranging. Predator hunting modes and habitat domains differed, with jewelfish being more active search predators that used slightly higher parts of the water column and less of the habitat structure relative to Mayan cichlids. In disagreement with our predictions, predation rates were similar between the two predators, antipredator responses were stronger to African jewelfish (except for predator inspections), and there was no difference in response between jewelfish-savvy and jewelfish-naive populations. These results suggest that despite the novelty of introduced predators, prey may be able to respond appropriately if non-native predator archetypes are similar enough to those of native predators, if prey rely
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Directory of Open Access Journals (Sweden)
Meyer Axel
2010-10-01
Full Text Available Abstract Background Elucidation of the mechanisms driving speciation requires detailed knowledge about the phylogenetic relationships and phylogeography of the incipient species within their entire ranges as well as their colonization history. The Midas cichlid species complex Amphilophus spp. has been proven to be a powerful model system for the study of ecological specialization, sexual selection and the mechanisms of sympatric speciation. Here we present a comprehensive and integrative phylogeographic analysis of the complete Midas Cichlid species complex in Nicaragua (> 2000 individuals covering the entire distributional range, using two types of molecular markers (the mitochondrial DNA control region and 15 microsatellites. We investigated the majority of known lake populations of this species complex and reconstructed their colonization history in order to distinguish between alternative speciation scenarios. Results We found that the large lakes contain older and more diverse Midas Cichlid populations, while all crater lakes hold younger and genetically less variable species assemblages. The large lakes appear to have repeatedly acted as source populations for all crater lakes, and our data indicate that faunal exchange among crater lakes is extremely unlikely. Despite their very recent (often only a few thousand years old and common origin from the two large Nicaraguan lakes, all crater lake Midas Cichlid radiations underwent independent, but parallel, evolution, and comprise distinct genetic units. Indeed several of these crater lakes contain multiple genetically distinct incipient species that most likely arose through sympatric speciation. Several crater lake radiations can be traced back to a single ancestral line, but some appear to have more than one founding lineage. The timing of the colonization(s of each crater lake differs, although most of them occurred more (probably much more recently than 20,000 years ago. Conclusion The
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Barluenga, Marta; Meyer, Axel
2010-10-26
Elucidation of the mechanisms driving speciation requires detailed knowledge about the phylogenetic relationships and phylogeography of the incipient species within their entire ranges as well as their colonization history. The Midas cichlid species complex Amphilophus spp. has been proven to be a powerful model system for the study of ecological specialization, sexual selection and the mechanisms of sympatric speciation. Here we present a comprehensive and integrative phylogeographic analysis of the complete Midas Cichlid species complex in Nicaragua (> 2000 individuals) covering the entire distributional range, using two types of molecular markers (the mitochondrial DNA control region and 15 microsatellites). We investigated the majority of known lake populations of this species complex and reconstructed their colonization history in order to distinguish between alternative speciation scenarios. We found that the large lakes contain older and more diverse Midas Cichlid populations, while all crater lakes hold younger and genetically less variable species assemblages. The large lakes appear to have repeatedly acted as source populations for all crater lakes, and our data indicate that faunal exchange among crater lakes is extremely unlikely. Despite their very recent (often only a few thousand years old) and common origin from the two large Nicaraguan lakes, all crater lake Midas Cichlid radiations underwent independent, but parallel, evolution, and comprise distinct genetic units. Indeed several of these crater lakes contain multiple genetically distinct incipient species that most likely arose through sympatric speciation. Several crater lake radiations can be traced back to a single ancestral line, but some appear to have more than one founding lineage. The timing of the colonization(s) of each crater lake differs, although most of them occurred more (probably much more) recently than 20,000 years ago. The genetic differentiation of the crater lake populations
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Raeymaekers, Joost A M; Hablützel, Pascal I; Grégoir, Arnout F; Bamps, Jolien; Roose, Anna K; Vanhove, Maarten P M; Van Steenberge, Maarten; Pariselle, Antoine; Huyse, Tine; Snoeks, Jos; Volckaert, Filip A M
2013-02-14
Adaptation to different ecological environments is thought to drive ecological speciation. This phenomenon culminates in the radiations of cichlid fishes in the African Great Lakes. Multiple characteristic traits of cichlids, targeted by natural or sexual selection, are considered among the driving factors of these radiations. Parasites and pathogens have been suggested to initiate or accelerate speciation by triggering both natural and sexual selection. Three prerequisites for parasite-driven speciation can be inferred from ecological speciation theory. The first prerequisite is that different populations experience divergent infection levels. The second prerequisite is that these infection levels cause divergent selection and facilitate adaptive divergence. The third prerequisite is that parasite-driven adaptive divergence facilitates the evolution of reproductive isolation. Here we investigate the first and the second prerequisite in allopatric chromatically differentiated lineages of the rock-dwelling cichlid Tropheus spp. from southern Lake Tanganyika (Central Africa). Macroparasite communities were screened in eight populations belonging to five different colour morphs. Parasite communities were mainly composed of acanthocephalans, nematodes, monogeneans, copepods, branchiurans, and digeneans. In two consecutive years (2011 and 2012), we observed significant variation across populations for infection with acanthocephalans, nematodes, monogeneans of the genera Gyrodactylus and Cichlidogyrus, and the copepod Ergasilus spp. Overall, parasite community composition differed significantly between populations of different colour morphs. Differences in parasite community composition were stable in time. The genetic structure of Tropheus populations was strong and showed a significant isolation-by-distance pattern, confirming that spatial isolation is limiting host dispersal. Correlations between parasite community composition and Tropheus genetic differentiation were
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CRYOPRESERVATION OF RAM SPERM FROM AUTOCHTHONOUS BREEDS DURING A NON-MATING SEASON
Directory of Open Access Journals (Sweden)
Milko SABEV
2007-07-01
Full Text Available It is possible to collect and successfully cryopreserve ejaculates in a non-mating season from rams of the autochthonous breeds Karakachan, Cooper-red Shumen and Karnobat-local, raised in Bulgaria. Studies are in progress aiming the elaboration of optimal cryoprotective extenders and freezing technology.
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Koblmüller, Stephan; Salzburger, Walter; Sturmbauer, Christian
2004-01-01
The cichlid species flock of Lake Tanganyika is comprised of seven seeding lineages that evolved in step with changes of the lake environment. One seeding lineage diversified into at least six lineages within a short period of time. Our study focuses on the diversification of one of these lineages, the Ectodini, comprising highly specialized, sand- and rock-dwelling species. They display two distinct breeding styles: maternal and biparental mouthbrooding. By analyzing three mtDNA gene segments in 30 species representing all 13 described genera, we show that the Ectodini rapidly diversified into four clades at the onset of their radiation. The monotypic genus Grammatotria is likely to represent the most ancestral split, followed by the almost contemporary origin of three additional clades, the first comprising the benthic genus Callochromis, the second comprising the benthic genera Asprotilapia, Xenotilapia, Enantiopus, and Microdontochromis, and the third comprising the semi-pelagic genera Ophthalmotilapia, Cardiopharynx, Cyathopharynx, Ectodus, Aulonocranus, Lestradea, and Cunningtonia. Our study confirms the benthic and sand-dwelling life-style as ancestral. Rocky habitats were colonized independently in the Xenotilapia- and Ophthalmotilapia-clade. The Xenotilapia-clade comprises both maternal and biparental mouthbrooders. Their mode of breeding appears to be highly plastic: biparental mouthbrooding either evolved once in the common ancestor of the clade, to be reverted at least three times, or evolved at least five times independently from a maternally mouthbrooding ancestor. Furthermore, the genera Xenotilapia, Microdontochromis, Lestradea, and Ophthalmotilapia appeared paraphyletic in our analyses, suggesting the need of taxonomic revision.
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Müller, Gerd B.
2018-01-01
Advances in imaging and modeling facilitate the calculation of biomechanical forces in biological specimens. These factors play a significant role during ontogenetic development of cichlid pharyngeal jaws, a key innovation responsible for one of the most prolific species diversifications in recent times. MicroCT imaging of radiopaque-stained vertebrate embryos were used to accurately capture the spatial relationships of the pharyngeal jaw apparatus in two cichlid species (Haplochromis elegans and Amatitlania nigrofasciata) for the purpose of creating a time series of developmental stages using finite element models, which can be used to assess the effects of biomechanical forces present in a system at multiple points of its ontogeny. Changes in muscle vector orientations, bite forces, force on the neurocranium where cartilage originates, and stress on upper pharyngeal jaws are analyzed in a comparative context. In addition, microCT scanning revealed the presence of previously unreported cement glands in A. nigrofasciata. The data obtained provide an underrepresented dimension of information on physical forces present in developmental processes and assist in interpreting the role of developmental dynamics in evolution. PMID:29320528
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Directory of Open Access Journals (Sweden)
Tim Peterson
Full Text Available Advances in imaging and modeling facilitate the calculation of biomechanical forces in biological specimens. These factors play a significant role during ontogenetic development of cichlid pharyngeal jaws, a key innovation responsible for one of the most prolific species diversifications in recent times. MicroCT imaging of radiopaque-stained vertebrate embryos were used to accurately capture the spatial relationships of the pharyngeal jaw apparatus in two cichlid species (Haplochromis elegans and Amatitlania nigrofasciata for the purpose of creating a time series of developmental stages using finite element models, which can be used to assess the effects of biomechanical forces present in a system at multiple points of its ontogeny. Changes in muscle vector orientations, bite forces, force on the neurocranium where cartilage originates, and stress on upper pharyngeal jaws are analyzed in a comparative context. In addition, microCT scanning revealed the presence of previously unreported cement glands in A. nigrofasciata. The data obtained provide an underrepresented dimension of information on physical forces present in developmental processes and assist in interpreting the role of developmental dynamics in evolution.
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Torres-Dowdall, Julián; Golcher-Benavides, Jimena; Machado-Schiaffino, Gonzalo; Meyer, Axel
2017-09-01
Genetically based stable colour polymorphisms provide a unique opportunity to study the evolutionary processes that preserve genetic variability in the wild. Different mechanisms are proposed to promote the stability of polymorphisms, but only few empirical examples have been documented, resulting in an incomplete understanding of these mechanisms. A remarkable genetically determined stable colour polymorphism is found in the Nicaraguan Midas cichlid species complex (Amphilophus cf. citrinellus). All Midas cichlids start their life with a dark-grey coloration (dark morph), but individuals carrying the dominant "gold" allele (c. 10%) lose their melanophores later in life, revealing the underlying orange coloration (gold morph). How this polymorphism is maintained remains unclear. Two main hypotheses have been proposed, both suggesting differential predation upon colour morphs as the proximate mechanism. One predicts that the conspicuous gold morph is more likely to be preyed upon, but this disadvantage is balanced by their competitive dominance over the dark morph. The second hypothesis suggests a rare morph advantage where the rarer gold morph experiences less predation. Empirical evidence for either of these mechanisms is still circumstantial and inconclusive. We conducted two field experiments in a Nicaraguan crater lake using wax models simulating both morphs to determine predation pressure upon Midas cichlid colour morphs. First, we tested the interaction of coloration and depth on attack rate. Second, we tested the interaction of fish size and coloration. We contrasted the pattern of attacks from these experiments to the predicted predation patterns from the hypotheses proposed to explain the colour polymorphism's stability. Large models imitating colour morphs were attacked at similar rates irrespectively of their position in the water column. Yet, attacks upon small models resembling juveniles were directed mainly towards dark models. This resulted in a
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Directory of Open Access Journals (Sweden)
Renz Adina J
2011-01-01
Full Text Available Abstract Background Cichlid fishes have undergone rapid, expansive evolutionary radiations that are manifested in the diversification of their trophic morphologies, tooth patterning and coloration. Understanding the molecular mechanisms that underlie the cichlids' unique patterns of evolution requires a thorough examination of genes that pattern the neural crest, from which these diverse phenotypes are derived. Among those genes, the homeobox-containing Dlx gene family is of particular interest since it is involved in the patterning of the brain, jaws and teeth. Results In this study, we characterized the dlx genes of an African cichlid fish, Astatotilapia burtoni, to provide a baseline to later allow cross-species comparison within Cichlidae. We identified seven dlx paralogs (dlx1a, -2a, -4a, -3b, -4b, -5a and -6a, whose orthologies were validated with molecular phylogenetic trees. The intergenic regions of three dlx gene clusters (dlx1a-2a, dlx3b-4b, and dlx5a-6a were amplified with long PCR. Intensive cross-species comparison revealed a number of conserved non-coding elements (CNEs that are shared with other percomorph fishes. This analysis highlighted additional lineage-specific gains/losses of CNEs in different teleost fish lineages and a novel CNE that had previously not been identified. Our gene expression analyses revealed overlapping but distinct expression of dlx orthologs in the developing brain and pharyngeal arches. Notably, four of the seven A. burtoni dlx genes, dlx2a, dlx3b, dlx4a and dlx5a, were expressed in the developing pharyngeal teeth. Conclusion This comparative study of the dlx genes of A. burtoni has deepened our knowledge of the diversity of the Dlx gene family, in terms of gene repertoire, expression patterns and non-coding elements. We have identified possible cichlid lineage-specific changes, including losses of a subset of dlx expression domains in the pharyngeal teeth, which will be the targets of future functional
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Directory of Open Access Journals (Sweden)
W James Cooper
2010-03-01
Full Text Available How particular changes in functional morphology can repeatedly promote ecological diversification is an active area of evolutionary investigation. The African rift-lake cichlids offer a calibrated time series of the most dramatic adaptive radiations of vertebrate trophic morphology yet described, and the replicate nature of these events provides a unique opportunity to test whether common changes in functional morphology have repeatedly facilitated their ecological success.Specimens from 87 genera of cichlid fishes endemic to Lakes Tanganyka, Malawi and Victoria were dissected in order to examine the functional morphology of cichlid feeding. We quantified shape using geometric morphometrics and compared patterns of morphological diversity using a series of analytical tests. The primary axes of divergence were conserved among all three radiations, and the most prevalent changes involved the size of the preorbital region of the skull. Even the fishes from the youngest of these lakes (Victoria, which exhibit the lowest amount of skull shape disparity, have undergone extensive preorbital evolution relative to other craniofacial traits. Such changes have large effects on feeding biomechanics, and can promote expansion into a wide array of niches along a bentho-pelagic ecomorphological axis.Here we show that specific changes in trophic anatomy have evolved repeatedly in the African rift lakes, and our results suggest that simple morphological alterations that have large ecological consequences are likely to constitute critical components of adaptive radiations in functional morphology. Such shifts may precede more complex shape changes as lineages diversify into unoccupied niches. The data presented here, combined with observations of other fish lineages, suggest that the preorbital region represents an evolutionary module that can respond quickly to natural selection when fishes colonize new lakes. Characterizing the changes in cichlid trophic
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Takahashi, K; Nishida, M; Yuma, M; Okada, N
2001-01-01
Lake Malawi is home to more than 450 species of endemic cichlids, which provide a spectacular example of adaptive radiation. To clarify the phylogenetic relationships among these fish, we examined the presence and absence of SINEs (short interspersed repetitive elements) at orthologous loci. We identified six loci at which a SINE sequence had apparently been specifically inserted by retroposition in the common ancestor of all the investigated species of endemic cichlids in Lake Malawi. At another locus, unique sharing of a SINE sequence was evident among all the investigated species of endemic non-Mbuna cichlids with the exception of Rhamphochromis sp. The relationships were in good agreement with those deduced in previous studies with various different markers, demonstrating that the SINE method is useful for the elucidation of phylogenetic relationships among cichlids in Lake Malawi. We also characterized a locus that exhibited transspecies polymorphism with respect to the presence or absence of the SINE sequence among non-Mbuna species. This result suggests that incomplete lineage sorting and/or interspecific hybridization might have occurred or be occurring among the species in this group, which might potentially cause misinterpretation of phylogenetic data, in particular when a single-locus marker, such as a sequence in the mitochondrial DNA, is used for analysis.
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Castillo Cajas, Ruth F; Selz, Oliver M; Ripmeester, Erwin A P; Seehausen, Ole; Maan, Martine E
2012-01-01
Environmental variation in signalling conditions affects animal communication traits, with possible consequences for sexual selection and reproductive isolation. Using spectrophotometry, we studied how male coloration within and between populations of two closely related Lake Victoria cichlid
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Benefits of cooperation with genetic kin in a subsocial spider
DEFF Research Database (Denmark)
Schneider, J.M.; Bilde, T.
2008-01-01
also promote helping behavior in many cooperatively breeding taxa. Investigating transitional systems is therefore particularly suitable for understanding the influence of kin selection on the initial spread of cooperative behaviors. Here we investigated the role of kinship in cooperative feeding. We...... in prey capture and feed communally. We provide clear experimental evidence for net benefits of cooperating with kin. Genetic relatedness within groups and not association with familiar individuals directly improved feeding efficiency and growth rates, demonstrating a positive effect of kin cooperation...
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Rosenfield, Robert N.; Taft, Stephen J.; Stout, William E.; Driscoll, Timothy G.; Evans, David L.; Bozek, Michael A.
2009-01-01
Trichomoniasis is a digestive tract disease caused by ingestion of the protozoan Trichomonas gallinae. This disease can be a significant source of mortality. No deaths of nestlings could be attributed to trichomoniasis in Cooper's Hawks (Accipiter cooperii) breeding in urban and rural environs in Wisconsin, North Dakota, and British Columbia. We detected T. gallinae in four (5.2%) of 77 nestling Cooper's Hawks during 2006 and 2007 among 42 urban nests on new study areas in southeast Wisconsin and eastern North Dakota/western Minnesota. All four infected young fledged. We did not detect T. gallinae in 52 breeding adult Cooper's Hawks on two urban study sites, nor in 28 migrant hatching year (n = 24) and adult (n = 4) Cooper's Hawks at Hawk Ridge Nature Reserve, Duluth, Minnesota in 2006–2007. Overall, we detected T. gallinae in only 2.5% of 157 Cooper's Hawks in northcentral North America. These results suggest a low prevalence of T. gallinae in Cooper's Hawks in the northern part of this hawk's breeding range.
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Proceedings of the FNCA workshop on plant mutation breeding 2001. Molecular biological techniques
International Nuclear Information System (INIS)
Kume, Tamikazu; Watanabe, Kazuo; Tano, Shigemitsu
2002-02-01
The FNCA (Forum for Nuclear Cooperation in Asia) Workshop on Plant Mutation Breeding was held on 20-24 August 2001 in Bangkok, Thailand. The Workshop was sponsored by the Ministry of Education, Culture, Sports, Science and Technology (MEXT). The Kasetsart University (KU), the Office of Atomic Energy for Peace (OAEP) and Department of Agriculture (DOA) acted as local host and the organizer with the cooperation of the Ministry of Agriculture, Forestry and Fisheries (MAFF) of Japan, the Japan Atomic Industrial Forum (JAIF) and Japan Atomic Energy Research Institute (JAERI). The Workshop was attended by two participants, a Project Leader and an expert on molecular biological techniques for plant mutation breeding, from each of the participating countries, i.e. China, Indonesia, Malaysia, the Philippines and Vietnam. One participant from the Republic of Korea, nine participants from Japan and thirteen participants from Thailand including three invited speakers attended the Workshop. Eleven papers including three invited papers on the current status of molecular biological techniques for plant mutation breeding were presented. Discussions were focused to further regional cooperation, to review and discuss results of past activities. The Medium-Term Plan of the project on the application of radiation and radioisotopes for agriculture in participating countries of Regional Nuclear Cooperation Activities (RNCA) was formulated and agreed. This proceeding compiles the invited and contributed papers that were submitted from the speakers. (author)
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Helping enhances productivity in campo flicker ( Colaptes campestris) cooperative groups
Dias, Raphael Igor; Webster, Michael S.; Macedo, Regina H.
2015-06-01
Reproductive adults in many bird species are assisted by non-breeding auxiliary helpers at the nest, yet the impact of auxiliaries on reproduction is variable and not always obvious. In this study, we tested Hamilton's rule and evaluated the effect of auxiliaries on productivity in the facultative cooperative breeder campo flicker ( Colaptes campestris campestris). Campo flickers have a variable mating system, with some groups having auxiliaries and others lacking them (i.e., unassisted pairs). Most auxiliaries are closely related to the breeding pair (primary auxiliaries), but some auxiliaries (secondary auxiliaries) are unrelated females that joined established groups. We found no effect of breeder quality (body condition) or territory quality (food availability) on group productivity, but the presence of auxiliaries increased the number of fledglings produced relative to unassisted pairs. Nonetheless, the indirect benefit of helping was small and did not outweigh the costs of delayed breeding and so seemed insufficient to explain the evolution of cooperative breeding in campo flickers. We concluded that some ecological constraints must limit dispersal or independent breeding, making staying in the group a "best-of-a-bad-job" situation for auxiliaries.
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Report from the FAO/IAEA Plant Breeding and Genetics Section
International Nuclear Information System (INIS)
1989-01-01
IDRC Workshop in Kenya, there was a regional seminar in Zambia, and there were missions of staff members to Burkina Faso, Cameroon, Cote d'lvoire, Ethiopia, Ghana, Nigeria, Senegal, Sudan, Tanzania, Uganda and Zaire. With financial support by the Italian Government, we expect to start in 1989 a regional co-operative programme including research contracts, training and workshops. Regional co-operation with plant breeders in Latin America continues under ARCAL (Regional Co-operative Arrangements for the Promotion of Nuclear Science and Technology in Latin America). The 7th Interregional Training Course on the Induction and Use of Mutations in Plant Breeding at the Seibersdorf Laboratory again saw 20 participants from 20 countries, selected among 61 applicants. The Section was responsible for 45 Technical Co-operation Projects involving 70 institutions in 37 countries. 52 scientists completed their training under IAEA fellowships
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Arbour, J H; López-Fernández, H
2014-11-01
Morphological, lineage and ecological diversity can vary substantially even among closely related lineages. Factors that influence morphological diversification, especially in functionally relevant traits, can help to explain the modern distribution of disparity across phylogenies and communities. Multivariate axes of feeding functional morphology from 75 species of Neotropical cichlid and a stepwise-AIC algorithm were used to estimate the adaptive landscape of functional morphospace in Cichlinae. Adaptive landscape complexity and convergence, as well as the functional diversity of Cichlinae, were compared with expectations under null evolutionary models. Neotropical cichlid feeding function varied primarily between traits associated with ram feeding vs. suction feeding/biting and secondarily with oral jaw muscle size and pharyngeal crushing capacity. The number of changes in selective regimes and the amount of convergence between lineages was higher than expected under a null model of evolution, but convergence was not higher than expected under a similarly complex adaptive landscape. Functional disparity was compatible with an adaptive landscape model, whereas the distribution of evolutionary change through morphospace corresponded with a process of evolution towards a single adaptive peak. The continentally distributed Neotropical cichlids have evolved relatively rapidly towards a number of adaptive peaks in functional trait space. Selection in Cichlinae functional morphospace is more complex than expected under null evolutionary models. The complexity of selective constraints in feeding morphology has likely been a significant contributor to the diversity of feeding ecology in this clade. © 2014 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.
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When cooperation begets cooperation: the role of key individuals in galvanizing support.
McAuliffe, Katherine; Wrangham, Richard; Glowacki, Luke; Russell, Andrew F
2015-12-05
Life abounds with examples of conspecifics actively cooperating to a common end, despite conflicts of interest being expected concerning how much each individual should contribute. Mathematical models typically find that such conflict can be resolved by partial-response strategies, leading investors to contribute relatively equitably. Using a case study approach, we show that such model expectations can be contradicted in at least four disparate contexts: (i) bi-parental care; (ii) cooperative breeding; (iii) cooperative hunting; and (iv) human cooperation. We highlight that: (a) marked variation in contributions is commonplace; and (b) individuals can often respond positively rather than negatively to the contributions of others. Existing models have surprisingly limited power in explaining these phenomena. Here, we propose that, although among-individual variation in cooperative contributions will be influenced by differential costs and benefits, there is likely to be a strong genetic or epigenetic component. We then suggest that selection can maintain high investors (key individuals) when their contributions promote support by increasing the benefits and/or reducing the costs for others. Our intentions are to raise awareness in--and provide testable hypotheses of--two of the most poorly understood, yet integral, questions regarding cooperative ventures: why do individuals vary in their contributions and when does cooperation beget cooperation? © 2015 The Author(s).
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Trust analysis and assessment in virtual organization breeding environments
Msanjila, S.S.; Afsarmanesh, H.
2008-01-01
Establishing trust relationships among the member organizations in a virtual organization breeding environment (VBE) is a pre-condition for their smooth cooperation. Furthermore, considering that effective creation of virtual organizations (VOs) is the main aim of the VBEs, the measurement of an
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How many species of cichlid fishes are there in African lakes?
Turner, G F; Seehausen, O; Knight, M E; Allender, C J; Robinson, R L
2001-03-01
The endemic cichlid fishes of Lakes Malawi, Tanganyika and Victoria are textbook examples of explosive speciation and adaptive radiation, and their study promises to yield important insights into these processes. Accurate estimates of species richness of lineages in these lakes, and elsewhere, will be a necessary prerequisite for a thorough comparative analysis of the intrinsic and extrinsic factors influencing rates of diversification. This review presents recent findings on the discoveries of new species and species flocks and critically appraises the relevant evidence on species richness from recent studies of polymorphism and assortative mating, generally using behavioural and molecular methods. Within the haplochromines, the most species-rich lineage, there are few reported cases of postzygotic isolation, and these are generally among allopatric taxa that are likely to have diverged a relatively long time in the past. However, many taxa, including many which occur sympatrically and do not interbreed in nature, produce viable, fertile hybrids. Prezygotic barriers are more important, and persist in laboratory conditions in which environmental factors have been controlled, indicating the primary importance of direct mate preferences. Studies to date indicate that estimates of alpha (within-site) diversity appear to be robust. Although within-species colour polymorphisms are common, these have been taken into account in previous estimates of species richness. However, overall estimates of species richness in Lakes Malawi and Victoria are heavily dependent on the assignation of species status to allopatric populations differing in male colour. Appropriate methods for testing the specific status of allopatric cichlid taxa are reviewed and preliminary results presented.
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Schwarzer, Julia; Swartz, Ernst Roelof; Vreven, Emmanuel; Snoeks, Jos; Cotterill, Fenton Peter David; Misof, Bernhard; Schliewen, Ulrich Kurt
2012-11-07
The megadiverse haplochromine cichlid radiations of the East African lakes, famous examples of explosive speciation and adaptive radiation, are according to recent studies, introgressed by different riverine lineages. This study is based on the first comprehensive mitochondrial and nuclear DNA dataset from extensive sampling of riverine haplochromine cichlids. It includes species from the lower River Congo and Angolan (River Kwanza) drainages. Reconstruction of phylogenetic hypotheses revealed the paradox of clearly discordant phylogenetic signals. Closely related mtDNA haplotypes are distributed thousands of kilometres apart and across major African watersheds, whereas some neighbouring species carry drastically divergent mtDNA haplotypes. At shallow and deep phylogenetic layers, strong signals of hybridization are attributed to the complex Late Miocene/Early Pliocene palaeohistory of African rivers. Hybridization of multiple lineages across changing watersheds shaped each of the major haplochromine radiations in lakes Tanganyika, Victoria, Malawi and the Kalahari Palaeolakes, as well as a miniature species flock in the Congo basin (River Fwa). On the basis of our results, introgression occurred not only on a spatially restricted scale, but massively over almost the whole range of the haplochromine distribution. This provides an alternative view on the origin and exceptional high diversity of this enigmatic vertebrate group.
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The Role of Ontogeny in the Evolution of Human Cooperation.
Tomasello, Michael; Gonzalez-Cabrera, Ivan
2017-09-01
To explain the evolutionary emergence of uniquely human skills and motivations for cooperation, Tomasello et al. (2012, in Current Anthropology 53(6):673-92) proposed the interdependence hypothesis. The key adaptive context in this account was the obligate collaborative foraging of early human adults. Hawkes (2014, in Human Nature 25(1):28-48), following Hrdy (Mothers and Others, Harvard University Press, 2009), provided an alternative account for the emergence of uniquely human cooperative skills in which the key was early human infants' attempts to solicit care and attention from adults in a cooperative breeding context. Here we attempt to reconcile these two accounts. Our composite account accepts Hrdy's and Hawkes's contention that the extremely early emergence of human infants' cooperative skills suggests an important role for cooperative breeding as adaptive context, perhaps in early Homo. But our account also insists that human cooperation goes well beyond these nascent skills to include such things as the communicative and cultural conventions, norms, and institutions created by later Homo and early modern humans to deal with adult problems of social coordination. As part of this account we hypothesize how each of the main stages of human ontogeny (infancy, childhood, adolescence) was transformed during evolution both by infants' cooperative skills "migrating up" in age and by adults' cooperative skills "migrating down" in age.
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A sensory bias has triggered the evolution of egg-spots in cichlid fishes.
Directory of Open Access Journals (Sweden)
Bernd Egger
Full Text Available Although, generally, the origin of sex-limited traits remains elusive, the sensory exploitation hypothesis provides an explanation for the evolution of male sexual signals. Anal fin egg-spots are such a male sexual signal and a key characteristic of the most species-rich group of cichlid fishes, the haplochromines. Males of about 1500 mouth-brooding species utilize these conspicuous egg-dummies during courtship--apparently to attract females and to maximize fertilization success. Here we test the hypothesis that the evolution of haplochromine egg-spots was triggered by a pre-existing bias for eggs or egg-like coloration. To this end, we performed mate-choice experiments in the basal haplochromine Pseudocrenilabrus multicolor, which manifests the plesiomorphic character-state of an egg-spot-less anal fin. Experiments using computer-animated photographs of males indeed revealed that females prefer images of males with virtual ('in-silico' egg-spots over images showing unaltered males. In addition, we tested for color preferences (outside a mating context in a phylogenetically representative set of East African cichlids. We uncovered a strong preference for yellow, orange or reddish spots in all haplochromines tested and, importantly, also in most other species representing more basal lines. This pre-existing female sensory bias points towards high-quality (carotenoids-enriched food suggesting that it is adaptive.
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BAERENDS, GP
This paper reports on experimental research undertaken to analyse the information processing mechanism by which the fry of substrate spawning cichlid fish visually recognise their guarding parent(s), already from the earliest time they are able to swim. The study is inspired by LORENZ' concept of
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Faunce, Craig H.; Patterson, Heather M.; Lorenz, Jerome J.
2002-01-01
Mayan cichlids (Cichlasoma urophthalmus) were collected monthly from March 1996 to October 1997 with hook-and-line gear at Taylor River, Florida, an area within the Crocodile Sanctuary of Everglades National Park, where human activities such as fishing are prohibited. Fish were aged by examining thin-sectioned otoliths, and past size-at-age information was generated by using back-calculation techniques. Marginal increment analysis showed that opaque growth zones were annuli deposited between ...
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Survival rates and lifetime reproduction of breeding male Cooper’s Hawks in Wisconsin, 1980-2005
Rosenfield, Robert N.; Bielefeldt, John; Rosenfield, Laura J.; Booms, Travis L.; Bozek, Michael A.
2009-01-01
There are few published data on annual survival and no reports of lifetime reproduction for breeding Cooper's Hawks (Accipiter cooperii). Breeding males (n = 105) in central and southeastern Wisconsin had an annual mortality rate of 19%, or a survival rate of 81% for birds ≤10 years of age. We did not detect significant differences in mortality rates between urban and rural habitats, nor between the earlier 13 years and later 13 years of this study. Male Cooper's Hawks produced from zero to 32 nestlings during their lifetimes. Body mass or size appeared unrelated to annual survivorship and lifetime reproduction, although lifetime reproduction was correlated strongly with longevity of breeding males. Fifteen of 66 males (23%) produced most (53%) of the nestlings. Our studies occurred in an area where breeding populations may be increasing with some of the highest reported productivity indices and nesting densities for this species. Habitat used for nesting on our Wisconsin study areas may be less important for survivorship and lifetime reproduction than acquisition of a nesting area in which a male will breed throughout his life.
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Extra-pair mating and evolution of cooperative neighbourhoods.
Directory of Open Access Journals (Sweden)
Sigrunn Eliassen
Full Text Available A striking but unexplained pattern in biology is the promiscuous mating behaviour in socially monogamous species. Although females commonly solicit extra-pair copulations, the adaptive reason has remained elusive. We use evolutionary modelling of breeding ecology to show that females benefit because extra-pair paternity incentivizes males to shift focus from a single brood towards the entire neighbourhood, as they are likely to have offspring there. Male-male cooperation towards public goods and dear enemy effects of reduced territorial aggression evolve from selfish interests, and lead to safer and more productive neighbourhoods. The mechanism provides adaptive explanations for the common empirical observations that females engage in extra-pair copulations, that neighbours dominate as extra-pair sires, and that extra-pair mating correlates with predation mortality and breeding density. The models predict cooperative behaviours at breeding sites where males cooperate more towards public goods than females. Where maternity certainty makes females care for offspring at home, paternity uncertainty and a potential for offspring in several broods make males invest in communal benefits and public goods. The models further predict that benefits of extra-pair mating affect whole nests or neighbourhoods, and that cuckolding males are often cuckolded themselves. Derived from ecological mechanisms, these new perspectives point towards the evolution of sociality in birds, with relevance also for mammals and primates including humans.
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Looking for unity in diversity: human cooperative childcare in comparative perspective.
Burkart, Judith M; van Schaik, Carel; Griesser, Michael
2017-12-20
Humans engage in cooperative childcare, which includes some elements not found in other animals, such as the presence of post-reproductive helpers, extensive food sharing among adults and a pervasive sexual division of labour. In animals, cooperative offspring care has typically been studied in two different contexts. The first mainly involves helpers contributing care in cooperatively breeding family groups; the second context is allomaternal care in species usually not categorized as cooperative breeders (e.g. plural and communal breeders, often without male care). Comparative analyses suggest that cooperative breeding and allomaternal care in plural and communal breeders have distinct evolutionary origins, with humans fitting neither pathway entirely. Nevertheless, some critical proximate mechanisms of helping, including hormonal regulators, are likely to be shared across species. Other mechanisms may vary among species, such as social tolerance, proactive prosociality or conditional mother-infant bonding. These are presumably associated with specific details of the care system, such as whether all group members contribute, or whether mothers can potentially raise offspring alone. Thus, cooperative offspring care is seen in different contexts across animal lineages, but may nonetheless share several important psychological characteristics. We end by discussing how work on humans may play a unifying role in studying cooperative offspring care. © 2017 The Author(s).
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Plant breeding and genetics newsletter. No. 26, January 2011
International Nuclear Information System (INIS)
2011-01-01
The Plant Breeding and Genetics Section (PBGS) in IAEA Headquarters, Vienna and the Plant Breeding and Genetics Laboratory (PBGL) in Seibersdorf are very grateful for the input and support of experts, consultants and lecturers from all the Member States that helped us implement our programmatic activities. We had the honour and the privilege to host 46 trainees, fellows, interns and scientific visitors for a total of 51 training months. Every single one has enriched this programme and we fondly remember our fruitful discussions. The Plant Breeding and Genetics Subprogramme provides technical support to Member States through the development and the promotion of technology packages based on mutation induction and efficiency enhancing molecular and biotechnologies applied to crop improvement through adaptive R and D in our Laboratory and four CRPs. This year, we worked on transferring these technology packages to 96 Member States by providing technical and scientific support through 63 national, regional and interregional Technical Cooperation Projects (TCPs) that are managed by IAEA's Department of Technical Cooperation. This transfer of technologies assists Member States in the implementation of national crop improvement programmes with specific breeding objectives or regional programmes addressing abiotic and/or biotic stresses, which represent serious threats impeding crop productivity in wide areas mostly in the developing world. In this issue, you will find more about services in support of activities in Member States, training and human capacity development and technology development/adaptation in the PBGL, including work on impact of NaCl stress on the biomass and mineral nutrient assimilation in different rice varieties, comparative studies of different mutagens on seed propagated crops, protocols and guidelines for mutation breeding lower cost molecular assays, and targeting deleterious mutations (including positive control kits)
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Urban, Elizabeth H; Mannan, R William
2014-01-01
Trichomoniasis, caused by the protozoan Trichomonas gallinae, affects a variety of species worldwide including avivorious raptors. Existing information suggests that the disease is most prevalent in young birds, and differential susceptibility to trichomoniasis among individuals in different age groups was documented in Cooper's Hawks (Accipiter cooperii) nesting in Tucson, Arizona. In that population, 85% of nestling Cooper's Hawks had T. gallinae in their oral cavity, compared to only 1% of breeding-age hawks. Trichomonads generally are sensitive to environmental pH and we explored the possibility that differences in oral pH may contribute to the differential prevalence of infection between age groups. We measured the pH of the fluid in the oral cavity in 375 Cooper's Hawks from three age groups (nestlings, fledglings, and breeding age) in Tucson, Arizona, in 2010 and 2011 and clinically tested for T. gallinae in a subsample of hawks. Oral pH of nestlings (∼ 6.8) was 7.3 times less acidic than in fledgling or breeding Cooper's Hawks (∼ 6.1). The incidence of T. gallinae was higher in nestlings (16%) than in either fledglings or breeding hawks (0%). Our findings indicate that oral pH becomes more acidic in Cooper's Hawks soon after they leave the nest. Trichomonas gallinae thrives when pH is between 6.5 and 7.5 (optimum 7.2), but is less viable in more acidic conditions. Higher levels of acidity in the oral cavity of fledglings and breeding Cooper's Hawks may reduce their susceptibility to trichomoniasis, and play a role in the differential prevalence of infection among age groups.
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Directory of Open Access Journals (Sweden)
Melanie Altner
2015-11-01
Full Text Available Identification of fossil cichlids is difficult, because the currently used diagnostic morphological characters for living cichlids are mostly soft tissue based and such characters are hardly preserved in fossils. During our recent fieldwork in the Central Kenya Rift (E-Africa, we discovered several exceptionally well-preserved fossil cichlids, which can be assigned to different lineages among the African Pseudocrenilabrinae. Here we present one of those new specimens. Its most conspicuous character is a lateral line divided into three segments. This specimen was found in the lacustrine sediments of the Middle Miocene site Waril, Tugen Hills, Kenya. The site represents the deposits of an ancient freshwater lake ca. 9-10 million years ago. Previous work on fossil leaves from the same site allow for the reconstruction of open vegetation surrounding the lake and pronounced dry seasons. Among the main further characteristics of the new fossil cichlid is a lachrimal with six lateral line canals, big cycloid scales and a low number of dorsal fin spines (XIII. The latter two characters are traceable in several members of tribes within the Pseudocrenilabrinae. However, a lachrimal with six lateral line canals is exclusively found in certain tribes of the EAR (East African Radiation within the Pseudocrenilabrinae. Moreover, the unique lateral line pattern is solely present in two genera of the EAR tribe Ectodini. However, the fossil shows cycloid scales, while modern Ectodini have ctenoid scales. Taken all evidence together, this fossil may perhaps represent an ancient lineage related to the Ectodini. Up to date, there is no definite fossil record of the members of the EAR. Our fossil may represent the first reliable calibration point for this group, which would be consistent with the previously reconstructed diversification time of the H-lineage (EAR tribes, except Boulengerochromini, Bathybatini, Trematocarini and Lamprologini and the Lamprologini ca
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Breeding to Optimize Agriculture in a Changing World
Directory of Open Access Journals (Sweden)
Jiankang Wang
2015-06-01
Full Text Available Breeding to Optimize Chinese Agriculture (OPTICHINA was a three-year EU–China project launched in June of 2011. As designed, the project acted as a new strategic model to reinforce systematic cooperation on agricultural research between Europe and China. The OPTICHINA International Conference “Breeding to Optimize Agriculture in a Changing World” was held in Beijing, May 26–29, 2014. The conference included six thematic areas: (1 defining and protecting the yield potential of traits and genes; (2 high-throughput precision phenotyping in the field; (3 molecular technologies in modern breeding; (4 plant ideotype; (5 data analysis, data management, and bioinformatics; and (6 national challenges and opportunities for China. The 10 articles collected in this special issue represent key contributions and topics of this conference. This editorial provides a brief introduction to the OPTICHINA project, followed by the main scientific points of articles published in this special issue. Finally, outcomes from a brainstorming discussion at the end of the conference are summarized, representing the authors' opinions on trends in breeding for a changing world.
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Hu, Yinan; Albertson, R Craig
2014-06-10
Adaptive variation in the craniofacial skeleton is a key component of resource specialization and habitat divergence in vertebrates, but the proximate genetic mechanisms that underlie complex patterns of craniofacial variation are largely unknown. Here we demonstrate that the Hedgehog (Hh) signaling pathway mediates widespread variation across a complex functional system that affects the kinematics of lower jaw depression--the opercular four-bar linkage apparatus--among Lake Malawi cichlids. By using a combined quantitative trait locus mapping and population genetics approach, we show that allelic variation in the Hh receptor, ptch1, affects the development of distinct bony elements in the head that represent two of three movable links in this functional system. The evolutionarily derived allele is found in species that feed from the water column, and is associated with shifts in anatomy that translate to a four-bar system capable of faster jaw rotation. Alternatively, the ancestral allele is found in species that feed on attached algae, and is associated with the development of a four-bar system that predicts slower jaw movement. Experimental manipulation of the Hh pathway during cichlid development recapitulates functionally salient natural variation in craniofacial geometry. In all, these results significantly extend our understanding of the mechanisms that fine-tune the craniofacial skeletal complex during adaptation to new foraging niches.
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Plant breeding and genetics newsletter. No. 3
International Nuclear Information System (INIS)
1999-06-01
This third issue of the Plant Breeding and Genetics Newsletter highlights forthcoming events including regional (Afra) training course on 'molecular characterization of genetic biodiversity in traditional and neglected crops selected for improvement through mutation techniques' and seminar on 'mutation techniques and biotechnology for tropical and subtropical plant improvement in Asia and Pacific regions'. Status of existing co-ordinated and technical co-operation research projects is also summarized
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Energy Technology Data Exchange (ETDEWEB)
Kume, Tamikazu; Watanabe, Kazuo; Tano, Shigemitsu (eds.) [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment
2001-03-01
The Workshop on Plant Mutation Breeding of FNCA (Forum for Nuclear Cooperation in Asia), was held on 9-13 October 2000 in Hanoi, Vietnam. The Workshop was co-sponsored by the Science and Technology Agency (STA), the Ministry of Science, Technology and Environment (MOSTE of Vietnam) and the Ministry of Agriculture and Rural Development (MARD of Vietnam) in cooperation with the Ministry of Agriculture, Forestry and Fisheries (MAFF), National Institute of Agrobiological Resources (NIAR of Vietnam), the Japan Atomic Industrial Forum (JAIF) and Japan Atomic Energy Research Institute (JAERI). Two Scientists, a Project Leader and an expert on methodology for plant/crop mutation breeding, participated from each of the member countries, i.e. China, Indonesia, Malaysia, the Philippines, Thailand, Vietnam and Japan. Also attending the Workshop were, one participant from Korea, seven participants from both Japan and Vietnam. The number of the participants in the Workshop totalled about sixty people including guests and observers. Sixteen papers including eight invited papers on the current status of methodology for plant/crop mutation breeding in the participating countries were presented. Discussions were focused on the subject concerning 'Effective Use of Physical/Chemical Mutagens', as well as a detailed report on the current status of research in each participating country. In addition, the topics of developing a mutant breeding database, an information exchange for plant/crop mutation breeding, and more tightly bound international co-operative research in the near future were also high on the agenda. This proceeding compiles the invited and contributed papers that were submitted from the speakers. (author)
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Energy Technology Data Exchange (ETDEWEB)
Kume, Tamikazu; Watanabe, Kazuo; Tano, Shigemitsu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment
2001-03-01
The Workshop on Plant Mutation Breeding of FNCA (Forum for Nuclear Cooperation in Asia), was held on 9-13 October 2000 in Hanoi, Vietnam. The Workshop was co-sponsored by the Science and Technology Agency (STA), the Ministry of Science, Technology and Environment (MOSTE of Vietnam) and the Ministry of Agriculture and Rural Development (MARD of Vietnam) in cooperation with the Ministry of Agriculture, Forestry and Fisheries (MAFF), National Institute of Agrobiological Resources (NIAR of Vietnam), the Japan Atomic Industrial Forum (JAIF) and Japan Atomic Energy Research Institute (JAERI). Two Scientists, a Project Leader and an expert on methodology for plant/crop mutation breeding, participated from each of the member countries, i.e. China, Indonesia, Malaysia, the Philippines, Thailand, Vietnam and Japan. Also attending the Workshop were, one participant from Korea, seven participants from both Japan and Vietnam. The number of the participants in the Workshop totalled about sixty people including guests and observers. Sixteen papers including eight invited papers on the current status of methodology for plant/crop mutation breeding in the participating countries were presented. Discussions were focused on the subject concerning 'Effective Use of Physical/Chemical Mutagens', as well as a detailed report on the current status of research in each participating country. In addition, the topics of developing a mutant breeding database, an information exchange for plant/crop mutation breeding, and more tightly bound international co-operative research in the near future were also high on the agenda. This proceeding compiles the invited and contributed papers that were submitted from the speakers. (author)
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ORGANIC ANIMAL BREEDING, CONDITIONS, DATA, FACTS, PLANS (EXAMPLES FROM CENTRAL EUROPE
Directory of Open Access Journals (Sweden)
J. SEREGI
2008-05-01
Full Text Available The authors consider that the organic animal breeding – as one of the methods with a significant influence on the human nutrition – is the necessary consequence of the 21st century. They present the way of establishing the organic breeding by some Hungarian and Central-European animal farms. They show some examples for the period of transformation into eco farms. The results cover the objective, personal, animal breed and feeding relations. Results of changing and operation: raw materials and products with some of their advantages are shown, just as some examples for protection of origin and food safety. Suggestions for marketing and cooperation, as well as for development are finally given, with special regard to rural development (employment, direct marketing and to the importance of environmental protection with regard to eco / alternative animal breeding.
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Kovács, Krisztina; Kis, Anna; Pogány, Ákos; Koller, Dóra; Topál, József
2016-12-01
Dogs have been proven to show several human-analogue social behaviors, and recent research raises the possibility that the oxytocin system is related to these. However, despite dogs' general tendency to excel in the domain of social cognition, there is increasing evidence that dogs' ability to utilize human signals may vary with breed. Moreover, breeds may show differences not only in their 'inborn' communicative abilities, but also in their learning skills related to these. The aim of the present study was to explore breed differences and breed-specific effects of oxytocin administration on different aspects of social responsiveness. Dogs from two markedly different breeds, Border Collies (cooperative workers) and Siberian Huskies (independent workers) were tested. After having received intranasal administration of oxytocin or placebo, subjects participated in three behavioral tests measuring social responsiveness. Our results show that there are several behavioral differences between the two breeds and also that there are differential effects of the oxytocin treatment. Border Collies were in general more susceptible to the 'social' effects of oxytocin compared to Siberian Huskies: after oxytocin administration they (1) looked more at the experimenter in the 'Unreachable food' situation, (2) looked more at the owner and shifted their gaze more between the sound source and the owner in a potentially dangerous situation, and (3) looked longer at the experimenter's eyes in the 'Tolerance of prolonged eye contact' test. These findings suggest that selection for enhanced cooperative abilities, possibly complemented by the effect of different social environments the two breeds experience, affects dogs' performance in several behavioral tests and that the neurohormonal background differently modulates social behavior in different working breeds. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Musilová, Zuzana; Kalous, Lukáš; Petrtýl, Miloslav; Chaloupková, Petra
2013-01-01
The headwaters of five large African river basins flow through the Bié Plateau in Angola and still remain faunistically largely unexplored. We investigated fish fauna from the Cuanza and Okavango-Zambezi river systems from central Angola. We reconstructed molecular phylogenies of the most common cichlid species from the region, Tilapia sparrmanii and Serranochromis macrocephalus, using both mitochondrial and nuclear markers. We found evidence for ichthyofaunal contact and gene flow between the Cuanza and Okavango-Zambezi watersheds in the Bié Plateau in central Angola. Waterfalls and rapids also appeared to restrict genetic exchange among populations within the Cuanza basin. Further, we found that the Angolan Serranochromis cichlid fishes represent a monophyletic lineage with respect to other haplochromines, including the serranochromines from the Congo and Zambezi rivers. This study represents an important initial step in a biodiversity survey of this extremely poorly explored region, as well as giving further understanding to species distributions and gene flow both between and within river basins. PMID:23724120
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Razo-Mendivil, Ulises; Vázquez-Domínguez, Ella; de León, Gerardo Pérez-Ponce
2013-12-01
Genetic analyses of hosts and their parasites are key to understand the evolutionary patterns and processes that have shaped host-parasite associations. We evaluated the genetic structure of the digenean Crassicutis cichlasomae and its most common host, the Mayan cichlid "Cichlasoma" urophthalmus, encompassing most of their geographical range in Middle-America (river basins in southeastern Mexico, Belize, and Guatemala together with the Yucatan Peninsula). Genetic diversity and structure analyses were done based on 167 cytochrome c oxidase subunit 1 sequences (330 bp) for C. cichlasomae from 21 populations and 161 cytochrome b sequences (599 bp) for "C." urophthalmus from 26 populations. Analyses performed included phylogenetic tree estimation under Bayesian inference and maximum likelihood analysis, genetic diversity, distance and structure estimates, haplotype networks, and demographic evaluations. Crassicutis cichlasomae showed high genetic diversity values and genetic structuring, corresponding with 4 groups clearly differentiated and highly divergent. Conversely, "C." urophthalmus showed low levels of genetic diversity and genetic differentiation, defined as 2 groups with low divergence and with no correspondence with geographical distribution. Our results show that species of cichlids parasitized by C. cichlasomae other than "C." urophthalmus, along with multiple colonization events and subsequent isolation in different basins, are likely factors that shaped the genetic structure of the parasite. Meanwhile, historical long-distance dispersal and drought periods during the Holocene, with significant population size reductions and fragmentations, are factors that could have shaped the genetic structure of the Mayan cichlid.
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Konijnendijk, N.; Joyce, D.A.; Mrosso, H.D.J.; Egas, M.; Seehausen, O.
2011-01-01
We examined genetic structure among five species of Lake Victoria haplochromine cichlids in four island communities, using a full factorial sampling design that compared genetic differentiation between pairs of species and populations of varying morphological similarity and geographical proximity.
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Hennig, K.; Verkerk, R.; Boekel, van M.A.J.S.; Dekker, M.; Bonnema, A.B.
2014-01-01
Nutritional quality of vegetables is affected by several steps in the food chain. Up to now the effects of these different steps are mostly studied separately. We propose the cooperation between plant breeding and food technology by using food technological parameters as breeding traits to identify
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Manousaki, Tereza; Hull, Pincelli M; Kusche, Henrik; Machado-Schiaffino, Gonzalo; Franchini, Paolo; Harrod, Chris; Elmer, Kathryn R; Meyer, Axel
2013-02-01
The study of parallel evolution facilitates the discovery of common rules of diversification. Here, we examine the repeated evolution of thick lips in Midas cichlid fishes (the Amphilophus citrinellus species complex)-from two Great Lakes and two crater lakes in Nicaragua-to assess whether similar changes in ecology, phenotypic trophic traits and gene expression accompany parallel trait evolution. Using next-generation sequencing technology, we characterize transcriptome-wide differential gene expression in the lips of wild-caught sympatric thick- and thin-lipped cichlids from all four instances of repeated thick-lip evolution. Six genes (apolipoprotein D, myelin-associated glycoprotein precursor, four-and-a-half LIM domain protein 2, calpain-9, GTPase IMAP family member 8-like and one hypothetical protein) are significantly underexpressed in the thick-lipped morph across all four lakes. However, other aspects of lips' gene expression in sympatric morphs differ in a lake-specific pattern, including the magnitude of differentially expressed genes (97-510). Generally, fewer genes are differentially expressed among morphs in the younger crater lakes than in those from the older Great Lakes. Body shape, lower pharyngeal jaw size and shape, and stable isotopes (δ(13)C and δ(15)N) differ between all sympatric morphs, with the greatest differentiation in the Great Lake Nicaragua. Some ecological traits evolve in parallel (those related to foraging ecology; e.g. lip size, body and head shape) but others, somewhat surprisingly, do not (those related to diet and food processing; e.g. jaw size and shape, stable isotopes). Taken together, this case of parallelism among thick- and thin-lipped cichlids shows a mosaic pattern of parallel and nonparallel evolution. © 2012 Blackwell Publishing Ltd.
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Gonad development in Midas cichlids and the evolution of sex change in fishes.
Oldfield, Ronald G
2011-01-01
Some fishes mature and function as one sex and later transform to the other sex in response to social interactions. Previous evidence suggested that a change in developmental timing may be involved in the evolution of adult sex change in fishes. The most recent support for this idea came from reports that sex in the Midas cichlid, Amphilophus citrinellus, was determined by social conditions experienced at the juvenile stage. Differentiation as a male was reported to be dependent on large body size relative to group-mates, and thought to be mediated through aggressive interactions. Here I demonstrate that socially controlled sex determination does not occur as was originally reported. Previously, I found that sex was not associated with body size in juveniles either in nature or in captivity. Similarly, I found no association between aggressive behavior and sex in juveniles. I later demonstrated that socially controlled sex determination does not typically occur in the Midas cichlid and closely related species and supported an alternative mechanism to explain large body size in adult males. Finally, in the current study I analyze gonad histology of fish from the same population used by the original authors and lay to rest the idea of socially controlled sex determination in this species. Recent observations of socially controlled sex determination in juveniles of species that typically change sex at the adult stage are examples of phenotypic plasticity, not genetic variation. Therefore, juvenile socially controlled sex determination does not support a theory that a change in developmental timing is involved in the evolution of adult sex change in fishes. © 2011 Wiley Periodicals, Inc.
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Directory of Open Access Journals (Sweden)
Mahdi Banaee
2014-12-01
Full Text Available Background: Aquatic ecosystems are frequently subjected to contamination by toxic heavy metals and pesticides, yet very little is known about the influence of pesticides on bioaccumulation of heavy metals in aquatic organisms. Mercury is a toxic metal with no known biological benefit to organisms. Bioavailability of mercury in aquatic environments depends on biological and non-biological parameters including other pollutants. Therefore, the objectives of this research were to determine the effects of permethrin on bioaccumulation of mercury in zebra cichlid. Methods: Acute toxicity (LC50 of permethrin and mercury chloride was evaluated by estimating mortality in Probit Model in SPSS (version 19.0 IBM. In sub-lethal toxicity, zebra cichlid (Cichlasoma nigrofasciatum was exposed to various concentrations of permethrin (0.0, 0.40, 0.80, 1.20 and 1.60 µg.L-1 combined with 20 µg.L-1 mercury chloride for 15 days. At the end of the experiment, mercury concentrations were measured using ICP-OES-Perkin elmer (optima 7300-DV. Results: 96 h LC50 values of permethrin and mercury for C. nigrofasciatum were calculated to be 17.55 µg.L-1 and 140.38 µg.L-1, respectively. Our results clearly showed that the bioaccumulation of mercury in the specimens increased with increasing concentrations of permethrin to 1.20 and 1.60 µg.L-1. Conclusion: Increasing the concentration of permethrin had synergistic effects on the bioaccumulation of mercury in fish.
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Regional cooperation to stimulate technical progress
International Nuclear Information System (INIS)
Ridvan, M.; Ehjrej, P.L.
1987-01-01
The main principles of the IAEA regional agreement on co-operation in the field of researches, elaboration and training of specialists in nuclear science and engineering for the states of Asia and Pacific Ocean region (RAC) and of the ARCAL program in Latin America are considered. The RAC projects envisage co-operation in the field of medicine (radiotherapy and nuclear methods, sterilization, etc.), agriculture (nuclear methods, raising of plants, using radiation mutations, food irradiation, etc.), industry (application of isotopes and radiation technology) and others. The ARCAL projects comprise radiation protection, nuclear control instruments, nuclear analytic methods, radioimmune analysis in stock-breeding, product irradiation, nuclear information, etc
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Razo-Mendivil, Ulises; Rosas-Valdez, Rogelio; Pérez-Ponce de León, Gerardo
2008-12-01
Oligogonotylus mayae n.sp. is described from the intestine of the Mayan cichlid Cichlasoma urophthalmus (Günther) in Ría Lagartos, Ría Celestún, and Estero Progreso, Yucatán State. This is the second species described for Oligogonotylus Watson, 1976, the other being O.manteri Watson, 1976. The new species is readily distinguished from O. manteri by the anterior extension of the vitelline follicles. In O. Manteri, Vitelline follicles are found entirely in the hindbody, extending posteriorly to mid-testicular level. Vitelline follicles in the new species extend from teh anterior margin of posterior testis to the region between the bentral sucker and the pharynx. comparison of approximately 1,850 bases of ribosomal DNA (ITS1, ITS2, 5.8S, and 28S), and 400 bases of cytochrome c oxidase subunit I (cox1) strongly supports the status of O. mayae as a new species, as compared to O. manteri collected from cichlids in other localities of Mexico, Belize, and Guatemala.
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Achievements of element technology development for breeding blanket
International Nuclear Information System (INIS)
Enoeda, Mikio
2005-03-01
Japan Atomic Energy Research Institute (JAERI) has been performing the development of breeding blanket for fusion power plant, as a leading institute of the development of solid breeder blankets, according to the long-term R and D program of the blanket development established by the Fusion Council of Japan in 1999. This report is an overview of development plan, achievements of element technology development and future prospect and plan of the development of the solid breeding blanket in JAERI. In this report, the mission of the blanket development activity in JAERI, key issues and roadmap of the blanket development have been clarified. Then, achievements of the element technology development were summarized and showed that the development has progressed to enter the engineering testing phase. The specific development target and plan were clarified with bright prospect. Realization of the engineering test phase R and D and completion of ITER test blanket module testing program, with universities/NIFS cooperation, are most important steps in the development of breeding blanket of fusion power demonstration plant. (author)
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Plant breeding and genetics newsletter. No. 14
International Nuclear Information System (INIS)
2004-12-01
These last six months, the Plant Breeding and Genetics (PBG) Section of the Joint FAO/IAEA Division (NAFA/AGE) implemented five Research Coordination Meetings (RCMs) and one Consultants Meeting for a new Coordinated Research Project (CRP) on 'Molecular tools for quality improvement in vegetatively propagated crops including banana and cassava' (8-11 November 2004, Vienna). Other salient points were the training courses we implemented this semester in the framework of different Technical Cooperation (TC) projects.Details about these activities inside this Newsletter
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Finkenwirth, Christa; Martins, Eloisa; Deschner, Tobias; Burkart, Judith M
2016-04-01
The neurohormone oxytocin (OT) is positively involved in the regulation of parenting and social bonding in mammals, and may thus also be important for the mediation of alloparental care. In cooperatively breeding marmosets, infants are raised in teamwork by parents and adult and sub-adult non-reproductive helpers (usually older siblings). Despite high intrinsic motivation, which may be mediated by hormonal priming, not all individuals are always equally able to contribute to infant-care due to competition among care-takers. Among the various care-taking behaviors, proactive food sharing may reflect motivational levels best, since it can be performed ad libitum by several individuals even if competition among surplus care-takers constrains access to infants. Our aim was to study the link between urinary OT levels and care-taking behaviors in group-living marmosets, while taking affiliation with other adults and infant age into account. Over eight reproductive cycles, 26 individuals were monitored for urinary baseline OT, care-taking behaviors (baby-licking, -grooming, -carrying, and proactive food sharing), and adult-directed affiliation. Mean OT levels were generally highest in female breeders and OT increased significantly in all individuals after birth. During early infancy, high urinary OT levels were associated with increased infant-licking but low levels of adult-affiliation, and during late infancy, with increased proactive food sharing. Our results show that, in marmoset parents and alloparents, OT is positively involved in the regulation of care-taking, thereby reflecting the changing needs during infant development. This particularly included behaviors that are more likely to reflect intrinsic care motivation, suggesting a positive link between OT and motivational regulation of infant-care. Copyright © 2016 Elsevier Inc. All rights reserved.
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Moscicki, Michele K; Reddon, Adam R; Hurd, Peter L
2011-09-01
Cerebral lateralization, the partitioning of cognitive function preferentially into one hemisphere of the brain, is a trait ubiquitous among vertebrates. Some species exhibit population level lateralization, where the pattern of cerebral lateralization is the same for most members of that species; however, other species show only individual level lateralization, where each member of the species has a unique pattern of lateralized brain function. The pattern of cerebral lateralization within a population and an individual has been shown to differ based on the stimulus being processed. It has been hypothesized that sociality within a species, such as shoaling behaviour in fish, may have led to the development and persistence of population level lateralization. Here we assessed cerebral lateralization in convict cichlids (Amatitlania nigrofasciata), a species that does not shoal as adults but that shoals briefly as juveniles. We show that both male and female convict cichlids display population level lateralization when in a solitary environment but only females show population level lateralization when in a perceived social environment. We also show that the pattern of lateralization differs between these two tasks and that strength of lateralization in one task is not predictive of strength of lateralization in the other task. Copyright © 2011 Elsevier B.V. All rights reserved.
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Report from the FAO/IAEA Plant Breeding and Genetics Section
International Nuclear Information System (INIS)
1988-01-01
In spite of a financial crisis of the UN-system, we were able to keep up essential activities. The co-ordinated research programme on cereal improvement using doubled-haploids but also heterosis from induced mutations started in 1986 and continued during the past year. A new regional co-ordinated research programme for Latin America, primarily for rice improvement had its first co-ordination meeting 30 March - 3 April 1987 in Quito, Ecuador. The co-ordinated research programme for identification and use of induced semi-dwarf mutants as alternative genetic sources for rice breeding completed its work with the final co-ordination meeting at Hangzhou, China, July 1987. In-vitro culture technology for mutation breeding is given high priority, e.g. for improving crop plant resistance to diseases. At the first co-ordination meeting of a new programme in September 1987, it was decided to concentrate efforts first on studying the use of toxins for in-vitro screening of resistant mutants and comparing toxin resistance with the reaction to pathogen attack under greenhouse and field conditions. Oil seeds and industrial crops have unfortunately so far received lower priority in FAO/IAEA projects, but we now look forward with some optimism to establish a global network on sesame improvement, in co-operation with the FAO Plant Production and Protection Division. A consultants meeting for this purpose was hosted by IAEA in Vienna in September 1987. The use of mutagenesis to accelerate the domestication of new crop plants - relevant for developing as well as for developed countries - had been subject of an expert discussion already in November 1986 (see MBNL No. 29). FAO and IAEA were advised to pay attention to this important task, but we still have to see whether funds become available. Vegetatively propagated plants like root and tuber crops, bananas and plantains, or woody perennials are looked upon frequently as a particular domaine of mutation breeding, which is not yet
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Koblmüller, Stephan; Salzburger, Walter; Obermüller, Beate; Eigner, Eva; Sturmbauer, Christian; Sefc, Kristina M
2011-06-01
The conditions of phenotypic and genetic population differentiation allow inferences about the evolution, preservation and loss of biological diversity. In Lake Tanganyika, water level fluctuations are assumed to have had a major impact on the evolution of stenotopic littoral species, though this hypothesis has not been specifically examined so far. The present study investigates whether subtly differentiated colour patterns of adjacent Tropheus moorii populations are maintained in isolation or in the face of continuous gene flow, and whether the presumed influence of water level fluctuations on lacustrine cichlids can be demonstrated in the small-scale population structure of the strictly stenotopic, littoral Tropheus. Distinct population differentiation was found even across short geographic distances and minor habitat barriers. Population splitting chronology and demographic histories comply with our expectation of old and rather stable populations on steeper sloping shore, and more recently established populations in a shallower region. Moreover, population expansions seem to coincide with lake level rises in the wake of Late Pleistocene megadroughts ~100 KYA. The imprint of hydrologic events on current population structure in the absence of ongoing gene flow suggests that phenotypic differentiation among proximate Tropheus populations evolves and persists in genetic isolation. Sporadic gene flow is effected by lake level fluctuations following climate changes and controlled by the persistence of habitat barriers during lake level changes. Since similar demographic patterns were previously reported for Lake Malawi cichlids, our data furthermore strengthen the hypothesis that major climatic events synchronized facets of cichlid evolution across the East African Great Lakes. © 2011 Blackwell Publishing Ltd.
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International Nuclear Information System (INIS)
Parente, Thiago E.M.; Oliveira, Ana C.A.X. de; Paumgartten, Francisco J.R.
2008-01-01
The induction of cytochrome P4501A-mediated activity (e.g. ethoxyresorufin-O-deethylation, EROD) has been used as a biomarker for monitoring fish exposure to AhR-receptor ligands such as polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and polychlorinated dibenzo-dioxins/furans (PCDD/Fs). In this study we found that hepatic EROD is induced in fish ('Nile tilapia', Oreochromis niloticus and 'acara', Geophagus brasiliensis) from the Guandu River (7-17-fold) and Jacarepagua Lake (7-fold), Rio de Janeiro, Brazil. Since both cichlid fish are consumed by the local population and the Guandu River is the main source of the drinking water supply for the greater Rio de Janeiro metropolitan area, pollution by cytochrome P4501A-inducing chemicals is a cause for concern and should be further investigated in sediments, water and biota. We additionally showed that EROD activity in the fish liver post-mitochondrial supernatant-simpler, cheaper and less time consuming to prepare than the microsomal fraction-is sufficiently sensitive for monitoring purposes. - Increased EROD activity in the liver of cichlid fishes indicated that Guandu River, the source of drinking water supply for Rio de Janeiro is polluted by CYP1A-inducing chemicals
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Breeding bird populations and habitat associations within the Savannah River Site (SRS).
Energy Technology Data Exchange (ETDEWEB)
Gauthreaux, Sidney, A.; Steven J. Wagner.
2005-06-29
Gauthreaux, Sidney, A., and Steven J. Wagner. 2005. Breeding bird populations and habitat associations within the Savannah River Site (SRS). Final Report. USDA Forest Service, Savannah River, Aiken, SC. 48 pp. Abstract: During the 1970's and 1980's a dramatic decline occurred in the populations of Neotropical migratory birds, species that breed in North America and winter south of the border in Central and South America and in the Caribbean. In 1991 an international initiative was mounted by U. S. governmental land management agencies, nongovernmental conservation agencies, and the academic and lay ornithological communities to understand the decline of Neotropical migratory birds in the Americas. In cooperation with the USDA Forest Service - Savannah River (FS - SR) we began 1992 a project directed to monitoring population densities of breeding birds using the Breeding Bird Census (BBC) methodology in selected habitats within the Savannah River Site SRS. In addition we related point count data on the occurrence of breeding Neotropical migrants and other bird species to the habitat data gathered by the Forest Inventory and Analysis (FIA) program of the USDA Forest Service and data on habitat treatments within forest stands.
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Eising, CM; Komdeur, J; Buys, J; Reemer, M; Richardson, DS; Richardson, David S.
The continental African Reed Warbler Acrocephalus baeticatus, like its relative the Seychelles Warbler Acrocephalus sechellensis, breeds in isolated patches. We studied the mating system of the African Reed Warbler to see whether this species, like the Seychelles Warbler, shows co-operative
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Riehl, Christina; Strong, Meghan J
2018-04-11
Social animals often form long-lasting relationships with fellow group members, usually with close kin. In primates, strong social bonds have been associated with increased longevity, offspring survival and reproductive success. However, little is known about the fitness effects of social bonds between non-kin, especially outside of mammals. In this study, we use long-term field research on a cooperatively breeding bird, the greater ani ( Crotophaga major ), to ask whether adult females benefit by remaining in long-term associations with unrelated, co-breeding females. We find that females that have previously nested together synchronize their reproduction more rapidly than those nesting with unfamiliar partners, which leads to lower competition and higher fledging success. Importantly, although previous experience with a co-breeding female influenced reproductive synchrony, the degree of reproductive synchrony did not influence whether co-breeding females remained together in subsequent years, ruling out the alternate hypothesis that highly synchronized females are simply more likely to remain together. These results indicate that switching groups is costly to females, and that social familiarity improves reproductive coordination. Stable social relationships therefore have significant fitness consequences for cooperatively nesting female birds, suggesting that direct benefits alone may favour the evolution of associations between non-relatives and contribute to long-term group stability. © 2018 The Author(s).
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Plant breeding and genetics newsletter, No. 24, January 2010
International Nuclear Information System (INIS)
2010-01-01
In the past biennium Plant Breeding and Genetics (PBG) subprogramme served 105 Member States through sixty-four national (30 Africa, 24 Asia and the Pacific, seven Latin America and the Caribbean, three Europe), seven regional (one Africa, four Asia and the Pacific, one Latin America and the Caribbean, one Europe) and one interregional Technical Cooperation Projects (TCPs), and six Coordinated Research Projects (CRPs) . Chosen highlights of these activities, you will find inside this issue
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Organic breeding: New trend in plant breeding
Directory of Open Access Journals (Sweden)
Berenji Janoš
2009-01-01
Full Text Available Organic breeding is a new trend in plant breeding aimed at breeding of organic cultivars adapted to conditions and expectations of organic plant production. The best proof for the need of organic cultivars is the existence of interaction between the performances of genotypes with the kind of production (conventional or organic (graph. 1. The adaptation to low-input conditions of organic production by more eddicient uptake and utilization of plant nutrients is especially important for organic cultivars. One of the basic mechanism of weed control in organic production is the competition of organic cultivars and weeds i.e. the enhanced ability of organic cultivars to suppress the weeds. Resistance/tolerance to diseases and pests is among the most important expectations toward the organic cultivars. In comparison with the methods of conventional plant breeding, in case of organic plant breeding limitations exist in choice of methods for creation of variability and selection classified as permitted, conditionally permitted and banned. The use of genetically modified organisms and their derivated along with induced mutations is not permitted in organic production. The use of molecular markers in organic plant breeding is the only permitted modern method of biotechnology. It is not permitted to patent the breeding material of organic plant breeding or the organic cultivars. .
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Wilson, Laura A B; Colombo, Marco; Sánchez-Villagra, Marcelo R; Salzburger, Walter
2015-11-20
Phenotype-environment correlations and the evolution of trait interactions in adaptive radiations have been widely studied to gain insight into the dynamics underpinning rapid species diversification. In this study we explore the phenotype-environment correlation and evolution of operculum shape in cichlid fishes using an outline-based geometric morphometric approach combined with stable isotope indicators of macrohabitat and trophic niche. We then apply our method to a sample of extinct saurichthyid fishes, a highly diverse and near globally distributed group of actinopterygians occurring throughout the Triassic, to assess the utility of extant data to inform our understanding of ecomorphological evolution in extinct species flocks. A series of comparative methods were used to analyze shape data for 54 extant species of cichlids (N = 416), and 6 extinct species of saurichthyids (N = 44). Results provide evidence for a relationship between operculum shape and feeding ecology, a concentration in shape evolution towards present along with evidence for convergence in form, and significant correlation between the major axes of shape change and measures of gut length and body elongation. The operculum is one of few features that can be compared in extant and extinct groups, enabling reconstruction of phenotype-environment interactions and modes of evolutionary diversification in deep time.
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Schwalbe, Margot A B; Webb, Jacqueline F
2015-04-01
Two sand-dwelling cichlids from Lake Malawi (Aulonocara stuartgranti, Tramitichromis sp.) that feed on benthic invertebrates, but have different lateral line phenotypes, use lateral line and/or visual cues to detect prey under light versus dark conditions. The current study examined how ecologically relevant variation in light intensity [0-800 lux (lx)] influences detection of prey (mobile, immobile) in each species by analyzing six behavioral parameters. Both species fed at light intensities ≥1 lx and trends in behavior among light intensities were informative. However, prey type and/or time of day (but not light intensity) predicted all four parameters analyzed with generalized linear mixed models in A. stuartgranti, whereas the interaction of light intensity and time of day predicted three of these parameters in Tramitichromis sp. Data suggest that the critical light intensity is 1-12 lx for both species, that the integration of visual and lateral line input explains differences in detection of mobile and immobile prey and behavioral changes at the transition from 1 to 0 lx in A. stuartgranti, and that Tramitichromis sp. likely uses binocular vision to locate prey. Differences in the sensory biology of species that exploit similar prey will have important implications for the trophic ecology of African cichlid fishes.
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Henning, Frederico; Renz, Adina Josepha; Fukamachi, Shoji; Meyer, Axel
2010-05-01
Natural populations of the Midas cichlid species in several different crater lakes in Nicaragua exhibit a conspicuous color polymorphism. Most individuals are dark and the remaining have a gold coloration. The color morphs mate assortatively and sympatric population differentiation has been shown based on neutral molecular data. We investigated the color polymorphism using segregation analysis and a candidate gene approach. The segregation patterns observed in a mapping cross between a gold and a dark individual were consistent with a single dominant gene as a cause of the gold phenotype. This suggests that a simple genetic architecture underlies some of the speciation events in the Midas cichlids. We compared the expression levels of several candidate color genes Mc1r, Ednrb1, Slc45a2, and Tfap1a between the color morphs. Mc1r was found to be up regulated in the gold morph. Given its widespread association in color evolution and role on melanin synthesis, the Mc1r locus was further investigated using sequences derived from a genomic library. Comparative analysis revealed conserved synteny in relation to the majority of teleosts and highlighted several previously unidentified conserved non-coding elements (CNEs) in the upstream and downstream regions in the vicinity of Mc1r. The identification of the CNEs regions allowed the comparison of sequences from gold and dark specimens of natural populations. No polymorphisms were found between in the population sample and Mc1r showed no linkage to the gold phenotype in the mapping cross, demonstrating that it is not causally related to the color polymorphism in the Midas cichlid.
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Modern Breeding Methods for Improving Protein Quality and Quantity in Plants
Energy Technology Data Exchange (ETDEWEB)
Dumanovic, J.; Ehrenberg, L. [Institute for the Application of Nuclear Energy in Agriculture, Veterinary Medicine and Forestry, Belgrade, Yugoslavia (Serbia)
1968-07-01
Against the background of the world's urgent need for increased protein production and for an improved quality of vegetable proteins, the ability of plant breeding to contribute to this need is discussed. With examples especially from maize and wheat, existing variations in protein content and protein composition are surveyed, together with the interdependence of these characteristics and their co-variation with the yield. It is shown that plant breeding has a great potential for improving the world's food situation. It is also shown that more rapid achievements are possible than is generally considered to be characteristic of plant-breeding techniques. Special emphasis is stressed on: (a) The capacity of mutation breeding, alone and in conjunction with other methods, to contribute to an increased production of high quality protein; (b) The necessity for the success of programmes whereby fast, cheap, and if possible non-destructive analytical procedures are developed to determine protein and amino acids; (c) The importance of the close collaboration of plant breeders with specialists in related subjects such as soil fertilization, physiology and nutrition, food technology, and biochemistry; (d) The importance of international co-operation and co-ordination. (author)
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Chapagain, Durga; Vir?nyi, Zs?fia; Wallis, Lisa J.; Huber, Ludwig; Serra, Jessica; Range, Friederike
2017-01-01
Aging of attentiveness affects cognitive functions like perception and working memory, which can seriously impact communication between dogs and humans, potentially hindering training and cooperation. Previous studies have revealed that aged laboratory beagles and pet Border collies (BC) show a decline in selective attention. However, much less is known about the aging of attentiveness in pet dogs in general rather than in specific breeds. Using 185 pet dogs (75 BC and 110 dogs of other breed...
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International Nuclear Information System (INIS)
Juerges, U.; Schroeder, J.H.; Sund, M.
1984-01-01
The agonistic behavior of mated convict cichlids (Cichlasoma nigrofasciatum) derived from gonial germ cells which were exposed to 0 (controls), 250, 500, 1,000, or 2,000 R of X-rays was determined by counting the attacks delivered to subadult conspecifics during the first eight days after spawning. While no day effects and no interactions with sex and radiation dose were found, males were significantly more aggressive in the treatment groups than the corresponding females. The highest aggressivness appeared in F 1 pairs derived from parental gonia irradiated with 250 R, and the lowest aggressiveness occurred in the 500-F 1 group. These two treatment groups differed significantly from each other, whereas no further significant differences could be detected. F 1 males derived from gonial X-irradiation with 750 R could not be mated successfully because they killed their own females. The changes of male aggressiveness reflect reversely the previously published results of changes in social cohesiveness of the individual cichlid fish. (author)
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International Nuclear Information System (INIS)
Nakagawa, Hitoshi
2006-01-01
Number of mutation species in the world is stated by some literature. 202 species are bread in Japan, which consists of 151 (by radiation), 20 (chemicals) and 31 (culture). The mutation indirect use species obtained 176 of rice, 3 wheat, 6 barleys, 8 soybeans, 3 tomatoes and 4 others. Low allergen rice, low glutelin rice, globulin deletion rice, disease resistant pear and apple, chrysanthemum and rose by radiation were studied. Control of mutation, genetics analysis, molecular scientific determination of mutation such as scale of mutation and RNA interference are reported. Advanced Radiation Application Research Center was build in Korea, 2005. Malaysian Institute for Nuclear Technology Research (MINT) is being built in Malaysia. Forum for Nuclear Cooperation in Asia (FNCA) is promoting radiation breeding in Japan. (S.Y.)
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Energy Technology Data Exchange (ETDEWEB)
Parente, Thiago E.M.; Oliveira, Ana C.A.X. de [Laboratorio de Toxicologia Ambiental, Escola Nacional de Saude Publica - FIOCRUZ, Av Brasil 4036, Predio de Expansao do Campus, Rio de Janeiro, RJ 21041-361 (Brazil); Paumgartten, Francisco J.R. [Laboratorio de Toxicologia Ambiental, Escola Nacional de Saude Publica - FIOCRUZ, Av Brasil 4036, Predio de Expansao do Campus, Rio de Janeiro, RJ 21041-361 (Brazil)], E-mail: paum@ensp.fiocruz.br
2008-03-15
The induction of cytochrome P4501A-mediated activity (e.g. ethoxyresorufin-O-deethylation, EROD) has been used as a biomarker for monitoring fish exposure to AhR-receptor ligands such as polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and polychlorinated dibenzo-dioxins/furans (PCDD/Fs). In this study we found that hepatic EROD is induced in fish ('Nile tilapia', Oreochromis niloticus and 'acara', Geophagus brasiliensis) from the Guandu River (7-17-fold) and Jacarepagua Lake (7-fold), Rio de Janeiro, Brazil. Since both cichlid fish are consumed by the local population and the Guandu River is the main source of the drinking water supply for the greater Rio de Janeiro metropolitan area, pollution by cytochrome P4501A-inducing chemicals is a cause for concern and should be further investigated in sediments, water and biota. We additionally showed that EROD activity in the fish liver post-mitochondrial supernatant-simpler, cheaper and less time consuming to prepare than the microsomal fraction-is sufficiently sensitive for monitoring purposes. - Increased EROD activity in the liver of cichlid fishes indicated that Guandu River, the source of drinking water supply for Rio de Janeiro is polluted by CYP1A-inducing chemicals.
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Interspecific reciprocity explains mobbing behaviour of the breeding chaffinches, Fringilla coelebs.
Krams, Indrikis; Krama, Tatjana
2002-01-01
When prey animals discover a predator close by, they mob it while uttering characteristic sounds that attract other prey individuals to the vicinity. Mobbing causes a predator to vacate its immediate foraging area, which gives an opportunity for prey individuals to continue their interrupted daily activity. Besides the increased benefits, mobbing behaviour also has its costs owing to injuries or death. The initiator of mobbing may be at increased risk of predation by attracting the predator's attention, especially if not joined by other neighbouring prey individuals. Communities of breeding birds have always been considered as temporal aggregations. Since an altruist could not prevent cheaters from exploiting its altruism in an anonymous community, this excluded any possibility of explaining mobbing behaviour in terms of reciprocal altruism. However, sedentary birds may have become acquainted since the previous non-breeding season. Migrant birds, forming anonymous communities at the beginning of the breeding season, may also develop closer social ties during the course of the breeding season. We tested whether a male chaffinch, a migrant bird, would initiate active harassment of a predator both at the beginning of the breeding season and a week later when it has become a member of a non-anonymous multi-species aggregation of sedentary birds. We expected that male chaffinches would be less likely to initiate a mob at the beginning of the breeding season when part of an anonymous multi-species aggregation of migratory birds. However, their mobbing activity should increase as the breeding season advances. Our results support these predictions. Cooperation among individuals belonging to different species in driving the predator away may be explained as interspecific reciprocity based on interspecific recognition and temporal stability of the breeding communities. PMID:12495502
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Monogamy and high relatedness do not preferentially favor the evolution of cooperation
Directory of Open Access Journals (Sweden)
Nonacs Peter
2011-03-01
Full Text Available Abstract Background Phylogenetic analyses strongly associate nonsocial ancestors of cooperatively-breeding or eusocial species with monogamy. Because monogamy creates high-relatedness family groups, kin selection has been concluded to drive the evolution of cooperative breeding (i.e., the monogamy hypothesis. Although kin selection is criticized as inappropriate for modeling and predicting the evolution of cooperation, there are no examples where specific inclusive fitness-based predictions are intrinsically wrong. The monogamy hypothesis may be the first case of such a flawed calculation. Results A simulation model mutated helping alleles into non-cooperative populations where females mated either once or multiply. Although multiple mating produces sibling broods of lower relatedness, it also increases the likelihood that one offspring will adopt a helper role. Examining this tradeoff showed that under a wide range of conditions polygamy, rather than monogamy, allowed helping to spread more rapidly through populations. Further simulations with mating strategies as heritable traits confirmed that multiple-mating is selectively advantageous. Although cooperation evolves similarly regardless of whether dependent young are close or more distant kin, it does not evolve if they are unrelated. Conclusions The solitary ancestral species to cooperative breeders may have been predominantly monogamous, but it cannot be concluded that monogamy is a predisposing state for the evolution of helping behavior. Monogamy may simply be coincidental to other more important life history characteristics such as nest defense or sequential provisioning of offspring. The differing predictive outcome from a gene-based model also supports arguments that inclusive fitness formulations poorly model some evolutionary questions. Nevertheless, cooperation only evolves when benefits are provided for kin: helping alleles did not increase in frequency in the absence of potential
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Directory of Open Access Journals (Sweden)
Assemu Tesfa
2017-01-01
Full Text Available The paper is initiated to design appropriate conservation strategies and breeding scheme for Fogera cattle breed that will be used as a guide for other Ethiopian indigenous cattle breed. Two types of data, on-farm and on-station, were used; the on-farm data was collected from three districts, namely, Fogera, Dera, and Bahir Dar Zuria; those are expected as the home of the breed. A total of 150 farmers, which are knowledgeable and having at least one cattle of Fogera phenotype in their herd, were purposively selected and interviewed. Additionally, farmer’s focus group discussion (FGD was conducted to capture the historical background, population, and distribution of the breed. SPSS (version 16 and index method was used to analyze the quantitative and scoring data’s, respectively. A meeting at national and regional level was also conducted to evaluate the existing conservation strategy and to identify the major stakeholders for the strategy. The main reasons to conserve Fogera breed are due to presence of interrelated constraints, presence of unique traits of the breed, better attitude of farmers, and decreasing population trend of the breed. Community-based in situ conservation strategy, to ensure the participation of the community, was designed for the breed. With the conservation strategy, related activities like feed development, animal health interventions, market linkage, and development of cooperatives will be implemented to improve the working environment. The stakeholders that are identified as an actor in the strategy should realize their honest participation for the sustainability of conservation and improvement of the breed.
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Correlated pay-offs are key to cooperation
Frommen, Joachim G.; Riehl, Christina
2016-01-01
The general belief that cooperation and altruism in social groups result primarily from kin selection has recently been challenged, not least because results from cooperatively breeding insects and vertebrates have shown that groups may be composed mainly of non-relatives. This allows testing predictions of reciprocity theory without the confounding effect of relatedness. Here, we review complementary and alternative evolutionary mechanisms to kin selection theory and provide empirical examples of cooperative behaviour among unrelated individuals in a wide range of taxa. In particular, we focus on the different forms of reciprocity and on their underlying decision rules, asking about evolutionary stability, the conditions selecting for reciprocity and the factors constraining reciprocal cooperation. We find that neither the cognitive requirements of reciprocal cooperation nor the often sequential nature of interactions are insuperable stumbling blocks for the evolution of reciprocity. We argue that simple decision rules such as ‘help anyone if helped by someone’ should get more attention in future research, because empirical studies show that animals apply such rules, and theoretical models find that they can create stable levels of cooperation under a wide range of conditions. Owing to its simplicity, behaviour based on such a heuristic may in fact be ubiquitous. Finally, we argue that the evolution of exchange and trading of service and commodities among social partners needs greater scientific focus. PMID:26729924
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Helpers increase the reproductive potential of offspring in cooperative meerkats
Russell, A.F; Young, A.J; Spong, G; Jordan, N.R; Clutton-Brock, T.H
2006-01-01
In both animal and human societies, individuals may forego personal reproduction and provide care to the offspring of others. Studies aimed at investigating the adaptive nature of such cooperative breeding systems in vertebrates typically calculate helper ‘fitness’ from relationships of helper numbers and offspring survival to independence. The aim of this study is to use observations and supplemental feeding experiments in cooperatively breeding meerkats, Suricata suricatta, to investigate whether helpers influence the long-term reproductive potential of offspring during adulthood. We show that helpers have a significant and positive influence on the probability that offspring gain direct reproductive success in their lifetimes. This effect arises because helpers both reduce the age at which offspring begin to reproduce as subordinates and increase the probability that they will compete successfully for alpha rank. Supplemental feeding experiments confirm the causality of these results. Our results suggest that one can neither discount the significance of helper effects when none is found nor necessarily estimate accurately the fitness benefit that helpers accrue, unless their effects on offspring are considered in the long term. PMID:17476771
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The oxidative costs of reproduction are group-size dependent in a wild cooperative breeder.
Cram, Dominic L; Blount, Jonathan D; Young, Andrew J
2015-11-22
Life-history theory assumes that reproduction entails a cost, and research on cooperatively breeding societies suggests that the cooperative sharing of workloads can reduce this cost. However, the physiological mechanisms that underpin both the costs of reproduction and the benefits of cooperation remain poorly understood. It has been hypothesized that reproductive costs may arise in part from oxidative stress, as reproductive investment may elevate exposure to reactive oxygen species, compromising survival and future reproduction and accelerating senescence. However, experimental evidence of oxidative costs of reproduction in the wild remains scarce. Here, we use a clutch-removal experiment to investigate the oxidative costs of reproduction in a wild cooperatively breeding bird, the white-browed sparrow weaver, Plocepasser mahali. Our results reveal costs of reproduction that are dependent on group size: relative to individuals in groups whose eggs were experimentally removed, individuals in groups that raised offspring experienced an associated cost (elevated oxidative damage and reduced body mass), but only if they were in small groups containing fewer or no helpers. Furthermore, during nestling provisioning, individuals that provisioned at higher rates showed greater within-individual declines in body mass and antioxidant protection. Our results provide rare experimental evidence that reproduction can negatively impact both oxidative status and body mass in the wild, and suggest that these costs can be mitigated in cooperative societies by the presence of additional helpers. These findings have implications for our understanding of the energetic and oxidative costs of reproduction, and the benefits of cooperation in animal societies. © 2015 The Authors.
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Steve McKeand; Saul Garcia; Josh Steiger; Jim Grissom; Ross Whetten; Fikret. Isik
2012-01-01
The elite breeding populations of loblolly pine (Pinus taeda L.) in the North Carolina State University Cooperative Tree Improvement Program are intensively managed for short-term genetic gain. Fusiform rust disease, caused by the fungus Cronartium quercuum f. sp. fusiforme, is the most economically...
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Report from the FAO/IAEA Plant Breeding and Genetics Section
Energy Technology Data Exchange (ETDEWEB)
NONE
1990-01-01
In 1989 we cared for 44 IAEA Technical Co-operation projects involving 35 developing countries and 64 different research institutions. Under the IAEA Research Contract Programme we had 70 active research contracts and 32 research agreements grouped into the following co-ordinated research programmes: use of induced mutations in connection with haploids and heterosis in cereals (1986-1991); improvement of rice and other cereals through mutation breeding in Latin America (1986-1991); use of induced mutation and in vitro culture techniques for improving crop plant resistance to diseases (1987-1992); mutation breeding of oil seed crops (1988-1993); improvement of root and tuber crops in tropical countries of Asia (1988-1993); in vitro mutation breeding of bananas and plantains (1988-1993); improvement of basic food crops in Africa through plant breeding, including the use of induced mutations (1989-1994). New research programmes cannot be started before 1991 when present ones are phasing out. The new research programmes could eventually deal with: domestication of new crop plants, improvement of industrial crops, the use of induced mutations to establish RFLP systems for genetic mapping and for mutant selection, the use of RFLP techniques for identification of induced genetic variation in vegetatively propagated plants and in vitro cultures, the control of plant virus diseases with the help of nuclear techniques. Project proposals on these topics are welcome, although their approval will depend upon the availability of funds. Six research co-ordination meetings were held in 1989 in Thailand (2), India, Austria, Chile and Italy. The Section was also actively involved in the 12th EUCARPIA Congress 'Science for Plant Breeding' (Goettingen, FRG, 27 February - 3 March) and in the 6th Congress of SABRAO 'Breeding Research: The Key to the Survival of the Earth' (Tsukuba, Japan, 21-25 August)
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El Grupo Cerúleo: Cooperation for Non-breeding Season Conservation of the Cerulean Warbler
David Mehlman; Paul. Hamel
2010-01-01
Without collaboration, conservation is impossible for long-distance migrants such as the Cerulean Warbler, a declining forest breeding bird in North America that overwinters in the Andes Mountains of South America. The Cerulean Warbler, one of the fastest declining woodland birds of eastern North America, is considered Vulnerable by BirdLife international, in the...
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Schrader, Matthew; Jarrett, Benjamin J M; Kilner, Rebecca M
2015-04-01
Studies of siblings have focused mainly on their competitive interactions and to a lesser extent on their cooperation. However, competition and cooperation are at opposite ends on a continuum of possible interactions and the nature of these interactions may be flexible with ecological factors tipping the balance toward competition in some environments and cooperation in others. Here we show that the presence of parental care and the density of larvae on the breeding carcass change the outcome of sibling interactions in burying beetle broods. With full parental care there was a strong negative relationship between larval density and larval mass, consistent with sibling competition for resources. In the absence of care, initial increases in larval density had beneficial effects on larval mass but further increases in larval density reduced larval mass. This likely reflects a density-dependent shift between cooperation and competition. In a second experiment, we manipulated larval density and removed parental care. We found that the ability of larvae to penetrate the breeding carcass increased with larval density and that feeding within the carcass resulted in heavier larvae than feeding outside the carcass. However, larval density did not influence carcass decay. © 2015 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.
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Nevado, B; Mautner, S; Sturmbauer, C; Verheyen, E
2013-08-01
Understanding how genetic variation is generated and maintained in natural populations, and how this process unfolds in a changing environment, remains a central issue in biological research. In this work, we analysed patterns of genetic diversity from several populations of three cichlid species from Lake Tanganyika in parallel, using the mitochondrial DNA control region. We sampled populations inhabiting the littoral rocky habitats in both very deep and very shallow areas of the lake. We hypothesized that the former would constitute relatively older, more stable and genetically more diverse populations, because they should have been less severely affected by the well-documented episodes of dramatic water-level fluctuations. In agreement with our predictions, populations of all three species sampled in very shallow shorelines showed traces of stronger population growth than populations of the same species inhabiting deep shorelines. However, contrary to our working hypothesis, we found a significant trend towards increased genetic diversity in the younger, demographically less stable populations inhabiting shallow areas, in comparison with the older and more stable populations inhabiting the deep shorelines. We interpret this finding as the result of the establishment of metapopulation dynamics in the former shorelines, by the frequent perturbation and reshuffling of individuals between populations due to the lake-level fluctuations. The repeated succession of periods of allopatric separation and secondary contact is likely to have further increased the rapid pace of speciation in lacustrine cichlids. © 2013 John Wiley & Sons Ltd.
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Hellig, Christoph J.; Kerschbaumer, Michaela; Sefc, Kristina M.; Koblmüller, Stephan
2010-07-01
The morphological versatility of the pharyngeal jaw of cichlid fishes is assumed to represent a key factor facilitating their unparalleled trophic diversification and explosive radiation. It is generally believed that the functional design of an organism relates to its ecology, and thus, specializations to different diets are typically associated with distinct morphological designs, especially manifested in the cichlids’ pharyngeal jaw apparatus. Thereby, the lower pharyngeal jaw (LPJ) incorporates some of the most predictive features for distinct diet-related morphotypes. Thus, considering that piscivorous cichlids experience an ontogenetic dietary shift from typically various kinds of invertebrates to fish, concomitant morphological changes in the LPJ are expected. Using Lepidiolamprologus elongatus, a top predator in the shallow rocky habitat of Lake Tanganyika, as model, and applying geometric and traditional morphometric techniques, we demonstrate an allometric change in ontogenetic LPJ shape development coinciding with the completion of the dietary shift toward piscivory. The piscivorous LPJ morphotype is initiated in juvenile fish by increasing elongation and narrowing of the LPJ and—when the fish reach a size of 80-90 mm standard length—further refined by the elongation of the posterior muscular processes, which serve as insertion for the fourth musculus levator externus. The enlarged muscular processes of the fully mature piscivorous morphotype provide for the construction of a powerful lever system, which allows the large individuals to process large prey fish and rely on exclusive piscivory.
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Buchanan, David S.; Lenstra, Johannes A.
2015-01-01
This chapter gives an overview on the different breeds of cattle (Bos taurus and B. indicus). Cattle breeds are presented and categorized according to utility and mode of origin. Classification and phylogeny of breeds are also discussed. Furthermore, a description of cattle breeds is provided.
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"Boldness" in the domestic dog differs among breeds and breed groups.
Starling, Melissa J; Branson, Nicholas; Thomson, Peter C; McGreevy, Paul D
2013-07-01
"Boldness" in dogs is believed to be one end of the shy-bold axis, representing a super-trait. Several personality traits fall under the influence of this super-trait. Previous studies on boldness in dogs have found differences among breeds, but grouping breeds on the basis of behavioural similarities has been elusive. This study investigated differences in the expression of boldness among dog breeds, kennel club breed groups, and sub-groups of kennel club breed groups by way of a survey on dog personality circulated among Australian dog-training clubs and internet forums and lists. Breed had a significant effect on boldness (F=1.63, numDF=111, denDF=272, ppurpose. Retrievers were significantly bolder than flushing and pointing breeds (Reg. Coef.=2.148; S.E.=0.593; pdogs. Differences in boldness among groups and sub-groups suggest that behavioural tendencies may be influenced by historical purpose regardless of whether that purpose still factors in selective breeding. Copyright © 2013 Elsevier B.V. All rights reserved.
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Duration of memory of dominance relationships in a group living cichlid
Hotta, Takashi; Takeyama, Tomohiro; Jordan, Lyndon Alexander; Kohda, Masanori
2014-09-01
Animal contests are costly and tend to escalate when rivals have similar competitive abilities. Individuals that remember dominance relationships with rivals may avoid repeated agonistic interactions and hence avoid the costs of repeated escalation of contests. However, it can be difficult to experimentally disentangle the effects of memory from those of loser effects (losers behaving subordinately due to prior defeats). Here, we test whether loser effects or individual memory mediate contest behaviour in the African cichlid, Julidochromis transcriptus. We find that on days 3 and 5 after initial contests, losers display subordinate behaviour to contest winners but not to novel contestants. However, this effect disappears after 7 days, at which time losers do not display subordinate behaviour to either rival. These results show that (1) this fish can recall a previously dominant contestant for up to 5 days and (2) as no subordinate displays were shown to the novel contestant, there are no evidences for loser effects in this species. Such short-term memory of past interactions may have broad significance in social species with repeated interactions.
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A Strategy for the Third Breeding Cycle of Loblolly Pine in the Southeastern U.S.
S.E. McKeand; F.E. Bridgwater
1998-01-01
A strategy for the North Carolina State University - Industry Cooperative Tree Improvement Program's third-cycle breeding for loblolly pine (Pinus taeda L.) was developed to provide genetic gain in the short-term as well as to maintain genetic diversity so that long-term genetic gains will also be possible. Our strategy will be to manage a...
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No sex-biased dispersal in a primate with an uncommon social system—cooperative polyandry
Directory of Open Access Journals (Sweden)
Samuel L. Díaz-Muñoz
2014-10-01
Full Text Available An influential hypothesis proposed by Greenwood (1980 suggests that different mating systems result in female and male-biased dispersal, respectively, in birds and mammals. However, other aspects of social structure and behavior can also shape sex-biased dispersal. Although sex-specific patterns of kin cooperation are expected to affect the benefits of philopatry and dispersal patterns, empirical evidence is scarce. Unlike many mammals, Saguinus geoffroyi (Geoffroy’s tamarin has a breeding system in which typically multiple males mate with a single breeding female. Males typically form cooperative reproductive partnerships between relatives, whereas females generally compete for reproductive opportunities. This system of cooperative polyandry is predicted to result in female-biased dispersal, providing an opportunity to test the current hypotheses of sex-biased dispersal. Here we test for evidence of sex-biased dispersal in S. geoffroyi using demographic and genetic data from three populations. We find no sex bias in natal dispersal, contrary to the prediction based on the mating patterns. This pattern was consistent after controlling for the effects of historical population structure. Limited breeding opportunities within social groups likely drive both males and females to disperse, suggesting that dispersal is intimately related to the social context. The integration of genetic and field data revealed that tamarins are another exception to the presumed pattern of male-biased dispersal in mammals. A shift in focus from mating systems to social behavior, which plays a role in most all processes expected to influence sex-bias in dispersal, will be a fruitful target for research both within species and across taxa.
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McLaughlin, Kirsty Elizabeth; Kunc, Hansjoerg P
2015-07-01
Anthropogenic noise can affect behaviour across a wide range of species in both terrestrial and aquatic environments. However, behaviours might not be affected in isolation. Therefore, a more holistic approach investigating how environmental stressors, such as noise pollution, affect different behaviours in concert is necessary. Using tank-based noise exposure experiments, we tested how changes in the acoustic environment affect the behaviour of the cichlid Amatitlania nigrofasciata. We found that exposure to anthropogenic noise affected a couple of behaviours: an increase in sheltering was accompanied by a decrease in foraging. Our results highlight the multiple negative effects of an environmental stressor on an individual's behaviour. Copyright © 2015 Elsevier B.V. All rights reserved.
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Costs Associated with Equine Breeding in Kentucky
Walker, Cassandra L.
There were approximately 9 million horses in the United States having a 102 billion impact on the U.S. economy (AHC, 2005). Over 1 million of those horses were involved in the breeding sector. In Kentucky, nearly 18% of the horse population have been involved in breeding. Managing an equine enterprise can be difficult, particularly given that many who undertake such endeavors do not have a background or education in business management. Kentucky Cooperative Extension has produced interactive spreadsheets to help horse owners better understand the costs associated with owning horses or managing certain equine businesses, including boarding and training operations. However, there has been little support for breeders. Therefore, the objectives of this study were to provide owners with a list of services offered for breeding and the costs associated with those services. Survey questions were created from a list of topics pertinent to equine breeding and from that list of questions, an electronic survey was created. The survey was sent via Qualtrics Survey Software to collect information on stallion and mare management costs as well as expenses related to owning and breeding. Question topics included veterinary and housing costs, management and advertising expenses, and membership fees. A total of 78 farms were selected from the 2013 breeder's listings for the Kentucky Quarter Horse Association (n = 39) and the Kentucky Thoroughbred Farm Managers' Club (n = 26), and other breed association contacts (n = 13). These farms were selected from the lists by outside individuals who were not related to the project. Participants were asked to answer all questions relevant to the farm. After the initial survey distribution, follow-up e-mails and phone calls were conducted in order to answer any questions participants might have had about the survey. Survey response rate was 32.1% (25 of 78 surveys returned). Farms in Kentucky had an average of two farm-owned and two outside
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A three-dimensional stereotaxic MRI brain atlas of the cichlid fish Oreochromis mossambicus.
Simões, José M; Teles, Magda C; Oliveira, Rui F; Van der Linden, Annemie; Verhoye, Marleen
2012-01-01
The African cichlid Oreochromis mossambicus (Mozambique tilapia) has been used as a model system in a wide range of behavioural and neurobiological studies. The increasing number of genetic tools available for this species, together with the emerging interest in its use for neurobiological studies, increased the need for an accurate hodological mapping of the tilapia brain to supplement the available histological data. The goal of our study was to elaborate a three-dimensional, high-resolution digital atlas using magnetic resonance imaging, supported by Nissl staining. Resulting images were viewed and analysed in all orientations (transverse, sagittal, and horizontal) and manually labelled to reveal structures in the olfactory bulb, telencephalon, diencephalon, optic tectum, and cerebellum. This high resolution tilapia brain atlas is expected to become a very useful tool for neuroscientists using this fish model and will certainly expand their use in future studies regarding the central nervous system.
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Development of breeding objectives for beef cattle breeding ...
African Journals Online (AJOL)
Mnr J F Kluyts
However, to solve the simultaneous equations the ... The aggregate breeding value represents a fundamental concept, the breeding objective, which is ..... Two properties characterise a linear programming problem. The first is additivity, ...
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International Nuclear Information System (INIS)
Ahmad, Zaiton; Oono, Yutaka
2016-03-01
This report summarizes Bilateral Cooperative Research between Japan Atomic Energy Agency and Malaysian Nuclear Agency (a representative of the Government of Malaysia) implemented from 2002 to 2012 under 'THE IMPLEMENTING ARRANGEMENT BETWEEN THE GOVERNMENT OF MALAYSIA AND THE JAPAN ATOMIC ENERGY AGENCY ON THE RESEARCH COOPERATION IN THE FIELD OF RADIATION PROCESSING'. The research activities in two Cooperative Research Programs, 'Mutation Induction of Orchid Plants by Ion Beams' and 'Generating New Ornamental Plant Varieties Using Ion Beams' performed 2002-2007 and 2007-2012, respectively, are contained. The lists of steering committee meetings, irradiation experiments, and publications/presentations of each program are also attached in the Appendixes. (author)
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Cultivation and breeding of Digitalis lanata in the Netherlands
Energy Technology Data Exchange (ETDEWEB)
Mastenbroek, C.
1985-09-01
After the second world war Marshall Aid funds were used to establish a cooperative organization for growing, drying, and selling Digitalis lanata (and other medicinal, aromatic, and culinary herbs) in the Netherlands. The crop is sown in mid April and the fully mechanised harvest of the leaves takes place from September to late November. The leaves are dried for 10-12 hours at 50 degrees C maximum. The aim of breeding trials is to improve leaf production, erect leaf attitude, resistance to Septoria leaf spot and to bolting, and a higher dry matter and digoxin content.
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Notes on breeding sharp-shinned hawks and cooper’s hawks in Barnwell County, South Carolina
Mark Vukovich; John C. Kilgo
2009-01-01
Breeding records of Accipiter striatus (Sharp-shinned Hawks) in the southeastern US are scattered and isolated. We documented a Sharp-shinned Hawk and Accipiter cooperii (Cooperâs Hawk) nest while conducting a telemetry study on Melanerpes erythrocephalus (Red-headed Woodpeckers) in Barnwell County, SC in 2006 and 2007. We report the first known nest of a Sharp-shinned...
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Directory of Open Access Journals (Sweden)
Rodrigo F. Bastos
Full Text Available Despite the importance of the pearl cichlid Geophagus brasiliensis for the aquarium fish trade worldwide and its wide distribution, many aspects of its biology, such as the relationships between its feeding ecology and reproductive behavior, are not fully understood in natural conditions on its native habitat. In this paper, we investigated its diet focusing on how differences in diet and food consumption are related to differences in gender and sexual maturity. The digestive tract of each individual was dissected and had its content analyzed, whereas each gonad was microscopically analyzed to determine gender (male/female and sexual maturity (immature/mature. A total of 28 females and 31 males were analyzed. Mature individuals were more common than immature specimens both for males (64.50% and females (64.30%. The analysis of 52 individuals with non-empty digestive tracts revealed a diet comprised of 27 items. According to the Index of Alimentary importance (%IAi, the most important food items in the diet were Gastropoda (37.30%, fragments of vascular plants (15.16%, detritus (10.14%, Amphipoda (9.24%, and fish scales (6.29%. Mature males had more empty stomachs (65.00% when compared to immature males (27.27% and immature (55.56% and mature females (40.00%. Also, mature females seemed to have more food consumption (greater mean values of total volume in their digestive tracts than mature males. Some hypotheses are proposed in order to distinguish if this gender-based difference in food consumption in mature individuals of the pearl cichlid could be associated with the development of primary and secondary sexual characteristics or with asymmetrical time invested in parental care activities.
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Vaslet, Amandine; France, Christine; Baldwin, Carole C.; Feller, Ilka C.
2012-01-01
Foraging habitats of juveniles of the Mayan cichlid, Cichlasoma urophthalmus (Günther, 1862), were investigated in two mangrove ponds located in Twin Cays offshore islet in Belize: Sink Hole pond (SH) and Hidden Lake pond (HL). Sink Hole pond is a semiclosed body of water, whereas Hidden Lake pond is connected by a channel to adjacent seagrass beds that surround the islet. Gut contents of 21 juvenile C. urophthalmus (9.8-13.2 cm total length) were analyzed, and five prey taxa were identified....
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Sutch, Richard
1986-01-01
This paper reviews the historical work on slave breeding in the ante-bellum United States. Slave breeding consisted of interference in the sexual life of slaves by their owners with the intent and result of increasing the number of slave children born. The weight of evidence suggests that slave breeding occurred in sufficient force to raise the rate of growth of the American slave population despite evidence that only a minority of slave-owners engaged in such practices.
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CASSAVA BREEDING I: THE VALUE OF BREEDING VALUE
Directory of Open Access Journals (Sweden)
Hernán Ceballos
2016-08-01
Full Text Available Breeding cassava relies on several selection stages (single row trial-SRT; preliminary; advanced; and uniform yield trials - UYT. This study uses data from 14 years of evaluations. From more than 20,000 genotypes initially evaluated only 114 reached the last stage. The objective was to assess how the data at SRT could be used to predict the probabilities of genotypes reaching the UYT. Phenotypic data from each genotype at SRT was integrated into the selection index (SIN used by the cassava breeding program. Average SIN from all the progenies derived from each progenitor was then obtained. Average SIN is an approximation of the breeding value of each progenitor. Data clearly suggested that some genotypes were better progenitors than others (e.g. high number of their progenies reaching the UYT, suggesting important variation in breeding values of progenitors. However, regression of average SIN of each parental genotype on the number of their respective progenies reaching UYT resulted in a negligible coefficient of determination (r2 = 0.05. Breeding value (e.g. average SIN at SRT was not efficient predicting which genotypes were more likely to reach the UYT stage. Number of families and progenies derived from a given progenitor were more efficient predicting the probabilities of the progeny from a given parent reaching the UYT stage. Large within-family genetic variation tends to mask the true breeding value of each progenitor. The use of partially inbred progenitors (e.g. S1 or S2 genotypes would reduce the within-family genetic variation thus making the assessment of breeding value more accurate. Moreover, partial inbreeding of progenitors can improve the breeding value of the original (S0 parental material and sharply accelerate genetic gains. For instance, homozygous S1 genotypes for the dominant resistance to cassava mosaic disease could be generated and selected. All gametes from these selected S1 genotypes would carry the desirable allele
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Directory of Open Access Journals (Sweden)
Flávia Barbosa Silva Botelho
2015-04-01
Full Text Available World’s ornamental plant market, including domestic market of several countries and its exports, is currently evaluated in 107 billion dollars yearly. Such estimate highlights the importance of the sector in the economy of the countries, as well as its important social role, as it represents one of the main activities, which contributes to income and employment. Therefore a well-structured plant breeding program, which is connected with consumers’ demands, is required in order to fulfill these market needs globally. Activities related to pre-breeding, conventional breeding, and breeding by biotechnological techniques constitute the basis for the successful development of new ornamental plant cultivars. Techniques that involve tissue culture, protoplast fusion and genetic engineering greatly aid conventional breeding (germplasm introduction, plant selection and hybridization, aiming the obtention of superior genotypes. Therefore it makes evident, in the literature, the successful employment of genetic breeding, since it aims to develop plants with commercial value that are also competitive with the ones available in the market.
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Kassam, Daud; Seki, Shingo; Horic, Michio; Yamaoka, Kosaku
2006-08-01
The apparent inter-lake morphological similarity among East African Great Lakes' cichlid species/genera has left evolutionary biologists asking whether such similarity is due to sharing of common ancestor or mere convergent evolution. In order to answer such question, we first used Geometric Morphometrics, GM, to quantify morphological similarity and then subsequently used Amplified Fragment Length Polymorphism, AFLP, to determine if similar morphologies imply shared ancestry or convergent evolution. GM revealed that not all presumed morphological similar pairs were indeed similar, and the dendrogram generated from AFLP data indicated distinct clusters corresponding to each lake and not inter-lake morphological similar pairs. Such results imply that the morphological similarity is due to convergent evolution and not shared ancestry. The congruency of GM and AFLP generated dendrograms imply that GM is capable of picking up phylogenetic signal, and thus GM can be potential tool in phylogenetic systematics.
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A simple language to script and simulate breeding schemes: the breeding scheme language
It is difficult for plant breeders to determine an optimal breeding strategy given that the problem involves many factors, such as target trait genetic architecture and breeding resource availability. There are many possible breeding schemes for each breeding program. Although simulation study may b...
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To breed or not to breed: a seabird's response to extreme climatic events
Cubaynes, Sarah; Doherty, Paul F.; Schreiber, E. A.; Gimenez, Olivier
2010-01-01
Intermittent breeding is an important life-history strategy that has rarely been quantified in the wild and for which drivers remain unclear. It may be the result of a trade-off between survival and reproduction, with individuals skipping breeding when breeding conditions are below a certain threshold. Heterogeneity in individual quality can also lead to heterogeneity in intermittent breeding. We modelled survival, recruitment and breeding probability of the red-footed booby (Sula sula), usin...
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Nelson-Flower, Martha J; Wiley, Elizabeth M; Flower, Tom P; Ridley, Amanda R
2018-03-20
Delayed dispersal is a key step in the evolution of familial animal societies and cooperative breeding. However, no consensus has been reached on the ecological and social circumstances driving delayed dispersal. Here, we test predictions from the ecological constraints and benefits of philopatry hypotheses as well as the recently proposed dual benefits hypothesis to better understand the evolution of group-living and cooperative breeding. Furthermore, we consider how individual social circumstances within groups affect dispersal decisions. We examine 11 years of life-history information on a wild population of cooperatively breeding southern pied babblers Turdoides bicolor. We investigate the effects of ecological conditions, natal-group membership and individual social context on male and female dispersal delays, disperser survival and acquisition of dominance. Female dispersal decisions are generally unconstrained by ecological or social circumstances. In contrast, males disperse in response to relaxed ecological constraints, decreases in nepotistic tolerance or when low social rank in the queue for dominance decreases their likelihood of gaining a dominant breeding position. Early dispersal by end-of-queue males often leads to a head-of-queue subordinate position in a non-natal group, thereby increasing access to dominant breeding positions. However, males and females remaining in natal groups gain benefits of philopatry via increased survival and, for head-of-queue males, very high likelihood of acquisition of a breeding position. Overall, predictions from the dual benefits hypothesis best describe these results, while some predictions from each of the ecological constraints and benefits of philopatry hypotheses were supported. The benefits of living and working together (collective action benefits) in large stable groups are of central importance in shaping dispersal delays in southern pied babbler societies. In addition, position in the subordinate social
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International Nuclear Information System (INIS)
Smith, D.; Billone, M.; Gohar, Y.; Baker, C.; Mori, S.; Kuroda, T.; Maki, K.; Takatsu, H.; Yoshida, H.; Raffray, A.; Sviatoslavsky, I.; Simbolotti, G.; Shatalov, G.
1991-01-01
The terms of reference for ITER provide for incorporation of a tritium breeding blanket with a breeding ratio as close to unity as practical. A breeding blanket is required to assure an adequate supply of tritium to meet the program objectives. Based on specified design criteria, a ceramic breeder concept with water coolant and an austenitic steel structure has been selected as the first option and lithium-lead blanket concept has been chosen as an alternate option. The first wall, blanket, and shield are integrated into a single unit with separate cooling systems. The design makes extensive use of beryllium to enhance the tritium breeding ratio. The design goals with a tritium breeding ratio of 0.8--0.9 have been achieved and the R ampersand D requirements to qualify the design have been identified. 4 refs., 8 figs., 2 tabs
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Schofield, P J; Loftus, W F; Fontaine, J A
2009-04-01
This study quantified the hypoxia tolerance of the Mayan cichlid Cichlasoma urophthalmus over a range of salinities. The species was very tolerant of hypoxia, using aquatic surface respiration (ASR) and buccal bubble holding when oxygen tensions dropped to <20 mmHg (c. 1.0 mg l(-1)) and 6 mmHg, respectively. Salinity had little effect on the hypoxia tolerance of C. urophthalmus, except that bubble holding was more frequent at the higher salinities tested. Levels of aggression were greatest at the highest salinity. The ASR thresholds of C. urophthalmus were similar to native centrarchid sunfishes from the Everglades, however, aggression levels for C. uropthalmus were markedly higher.
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Breeding biology of passerines in a subtropical montane forest in northwestern Argentina
Auer, S.K.; Bassar, R.D.; Fontaine, J.J.; Martin, T.E.
2007-01-01
The breeding ecology of south temperate bird species is less widely known than that of north temperate species, yet because they comprise a large portion of the world's avian diversity, knowledge of their breeding ecology can contribute to a more comprehensive understanding of the geographic diversity of avian reproductive traits and life history strategies. We provide the first detailed examination of the reproductive strategies of 18 forest passerines of subtropical, northwestern Argentina. Mean clutch sizes were smaller and egg mass was greater than for north temperate birds, but differed among species and nest types, with cavity-nesters having larger clutches than species with open-cup and enclosed nests. Across all species, the average breeding season duration was 50 days; thus, the common perception that southern species have smaller clutch sizes because of longer breeding seasons is not supported in this community. Daily nest predation rates were influenced by nest type, cavity nests suffering the least from predation, as found in north temperate systems. Only females incubated eggs in all but one species, whereas both parents fed and cared for nestlings in all species. Mean nest attentiveness was low compared to north temperate passerines. Mean hourly nestling feeding rates differed among species and were negatively related to nest predation risk. In short, coexisting species in this subtropical forest varied in their life history strategies, in part correlated with variation in nest predation risk, but also differing from north temperate species. ?? The Cooper Ornithological Society 2007.
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Directory of Open Access Journals (Sweden)
Scholz T.
2018-03-01
Full Text Available The Asian fish tapeworm, Schyzocotyle acheilognathi (Yamaguti, 1934 (Cestoda: Bothriocephalidea, is an invasive parasite of freshwater fishes that have been reported from more than 200 freshwater fish worldwide. It was originally described from a small cyprinid, Acheilognathus rombeus, in Japan but then has spread, usually with carp, minnows or guppies, to all continents including isolated islands such as Hawaii, Puerto Rico, Cuba or Sri Lanka. In the present account, we report the first case of the infection of a native cichlid fish, Ptychochromis cf. inornatus (Perciformes: Cichlidae, endemic to Madagascar, with S. acheilognathi. The way of introduction of this parasite to the island, which is one of the world’s biodiversity hotspots, is briefly discussed.
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The coevolution of long-term pair bonds and cooperation.
Song, Z; Feldman, M W
2013-05-01
The evolution of social traits may not only depend on but also change the social structure of the population. In particular, the evolution of pairwise cooperation, such as biparental care, depends on the pair-matching distribution of the population, and the latter often emerges as a collective outcome of individual pair-bonding traits, which are also under selection. Here, we develop an analytical model and individual-based simulations to study the coevolution of long-term pair bonds and cooperation in parental care, where partners play a Snowdrift game in each breeding season. We illustrate that long-term pair bonds may coevolve with cooperation when bonding cost is below a threshold. As long-term pair bonds lead to assortative interactions through pair-matching dynamics, they may promote the prevalence of cooperation. In addition to the pay-off matrix of a single game, the evolutionarily stable equilibrium also depends on bonding cost and accidental divorce rate, and it is determined by a form of balancing selection because the benefit from pair-bond maintenance diminishes as the frequency of cooperators increases. Our findings highlight the importance of ecological factors affecting social bonding cost and stability in understanding the coevolution of social behaviour and social structures, which may lead to the diversity of biological social systems. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.
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Morandini, Leonel; Ramallo, Martín Roberto; Moreira, Renata Guimarães; Höcht, Christian; Somoza, Gustavo Manuel; Silva, Ana; Pandolfi, Matías
2015-11-01
Reared animals for edible or ornamental purposes are frequently exposed to high aggression and stressful situations. These factors generally arise from conspecifics in densely breeding conditions. In vertebrates, serotonin (5-HT) has been postulated as a key neuromodulator and neurotransmitter involved in aggression and stress. The essential amino acid L-tryptophan (trp) is crucial for the synthesis of 5-HT, and so, leaves a gateway for indirectly augmenting brain 5-HT levels by means of a trp-enriched diet. The cichlid fish Cichlasoma dimerus, locally known as chanchita, is an autochthonous, potentially ornamental species and a fruitful laboratory model which behavior and reproduction has been studied over the last 15years. It presents complex social hierarchies, and great asymmetries between subordinate and dominant animals in respect to aggression, stress, and reproductive chance. The first aim of this work was to perform a morphological description of chanchita's brain serotonergic system, in both males and females. Then, we evaluated the effects of a trp-supplemented diet, given during 4weeks, on brain serotonergic activity, stress and sexual steroid hormones, and growth in isolated specimens. Results showed that chanchita's brain serotonergic system is composed of several populations of neurons located in three main areas: pretectum, hypothalamus and raphe, with no clear differences between males and females at a morphological level. Animals fed with trp-enriched diets exhibited higher forebrain serotonergic activity and a significant reduction in their relative cortisol levels, with no effects on sexual steroid plasma levels or growth parameters. Thus, this study points to food trp enrichment as a "neurodietary'' method for elevating brain serotonergic activity and decreasing stress, without affecting growth or sex steroid hormone levels. Copyright © 2015 Elsevier Inc. All rights reserved.
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Textbook animal breeding : animal breeding andgenetics for BSc students
Oldenbroek, Kor; Waaij, van der Liesbeth
2014-01-01
This textbook contains teaching material on animal breeding and genetics for BSc students. The text book started as an initiative of the Dutch Universities for Applied (Agricultural) Sciences. The textbook is made available by the Animal Breeding and Genomics Centre (ABGC) of Wageningen UR
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Tritium breeding in fusion reactors
International Nuclear Information System (INIS)
Abdou, M.A.
1982-10-01
Key technological problems that influence tritium breeding in fusion blankets are reviewed. The breeding potential of candidate materials is evaluated and compared to the tritium breeding requirements. The sensitivity of tritium breeding to design and nuclear data parameters is reviewed. A framework for an integrated approach to improve tritium breeding prediction is discussed with emphasis on nuclear data requirements
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Directory of Open Access Journals (Sweden)
Amandine Vaslet
Full Text Available Foraging habitats of juveniles of the Mayan cichlid, Cichlasoma urophthalmus (Günther, 1862, were investigated in two mangrove ponds located in Twin Cays offshore islet in Belize: Sink Hole pond (SH and Hidden Lake pond (HL. Sink Hole pond is a semiclosed body of water, whereas Hidden Lake pond is connected by a channel to adjacent seagrass beds that surround the islet. Gut contents of 21 juvenile C. urophthalmus (9.8-13.2 cm total length were analyzed, and five prey taxa were identified. In both mangrove ponds, C. urophthalmus were opportunistic carnivores and consumed primarily crustaceans. Plant material and detritus present in gut contents were most likely ingested incidentally when the fish foraged on small invertebrates. Carbon isotopic values of fish specimens from the two ponds were similar (mean ± SD of -19.2 ± 0.4‰ in SH and -19.4 ± 0.4‰ in HL, and were close to those of mangrove prey (mean ± SD = -20.2 ± 1.5‰, suggesting that this fish species forages in this habitat. Mixing models showed a higher contribution of mangrove food sources to the fish diet than seagrass food sources. This study reveals that young Mayan cichlids, inhabiting two Belize mangrove ponds, are generalists and opportunistic carnivores that forage on mangrove food sources and do not appear to move to adjacent seagrass beds to complement their diets. Understanding trophic linkages between aquatic consumers and food resources may contribute to better management of threatened coastal ecosystems.
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To breed or not to breed: a seabird's response to extreme climatic events.
Cubaynes, Sarah; Doherty, Paul F; Schreiber, E A; Gimenez, Olivier
2011-04-23
Intermittent breeding is an important life-history strategy that has rarely been quantified in the wild and for which drivers remain unclear. It may be the result of a trade-off between survival and reproduction, with individuals skipping breeding when breeding conditions are below a certain threshold. Heterogeneity in individual quality can also lead to heterogeneity in intermittent breeding. We modelled survival, recruitment and breeding probability of the red-footed booby (Sula sula), using a 19 year mark-recapture dataset involving more than 11,000 birds. We showed that skipping breeding was more likely in El-Niño years, correlated with an increase in the local sea surface temperature, supporting the hypothesis that it may be partly an adaptive strategy of birds to face the trade-off between survival and reproduction owing to environmental constraints. We also showed that the age-specific probability of first breeding attempt was synchronized among different age-classes and higher in El-Niño years. This result suggested that pre-breeders may benefit from lowered competition with experienced breeders in years of high skipping probabilities.
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Development of digestive enzymes in larvae of Mayan cichlid Cichlasoma urophthalmus.
López-Ramírez, G; Cuenca-Soria, C A; Alvarez-González, C A; Tovar-Ramírez, D; Ortiz-Galindo, J L; Perales-García, N; Márquez-Couturier, G; Arias-Rodríguez, L; Indy, J R; Contreras-Sánchez, W M; Gisbert, E; Moyano, F J
2011-03-01
The development of digestive enzymes during the early ontogeny of the Mayan cichlid (Cichlasoma urophthalmus) was studied using biochemical and electrophoretic techniques. From yolk absorption (6 days after hatching: dah), larvae were fed Artemia nauplii until 15 dah, afterward they were fed with commercial microparticulated trout food (45% protein and 16% lipids) from 16 to 60 dah. Several samples were collected including yolk-sac larvae (considered as day 1 after hatching) and specimens up to 60 dah. Most digestive enzymes were present from yolk absorption (5-6 dah), except for the specific acid proteases activity (pepsin-like), which increase rapidly from 8 dah up to 20 dah. Three alkaline proteases isoforms (24.0, 24.8, 84.5 kDa) were detected at 8 dah using SDS-PAGE zymogram, corresponding to trypsin, chymotrypsin and probably leucine aminopeptidase enzymes, and only one isoform was detected (relative electromobility, Rf = 0.54) for acid proteases (pepsin-like) from 3 dah onwards using PAGE zymogram. We concluded that C. urophthamus is a precocious fish with a great capacity to digest all kinds of food items, including artificial diets provided from 13 dah.
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Mendoza-Franco,E. F.; Vidal-Martínez,V.; Simá-Álvarez,R.; Rodríguez-Canul,R.; Vivas-Rodríguez,C.; Scholz,T.
1995-01-01
Cichlids, Cichlasoma urophthalmus, collected in a flooded quarry in the Yucatan Peninsula, Mexico, from January through June 1992, had high levels of infection with the ancyrocephaline Sciadicleithrum mexicanum (Monogena: Dactylogyridade) in all montlhly samples. Neither occurrence nor maturation of the worms eshibited any pronounced monthly fluctuation. The infection rate was found to be sizedependent, greater in longer fish. The worms occurred on primary lamellae of gill filaments of all ar...
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International Nuclear Information System (INIS)
2009-10-01
The International Atomic Energy Agency (IAEA) and the Regional Cooperative Agreement for Asia and the Pacific Region (RCA), with the technical support of the Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, implemented a Technical Cooperation (TC) project entitled Integrated Approach for Improving Livestock Production Using Indigenous Resources and Conserving the Environment (RAS/5/044). The 23 project counterparts and the IAEA technical officer, based on the lack of standard practices in the region with regard to selection of cattle for breeding purposes, and the need to properly manage the genetic resources within each country for improving the productivity of the existing stock while maintaining the unique and beneficial genetic characteristics of the indigenous breeds, agreed during the first meeting to request the IAEA to recruit a group of experts with the task of preparing guidelines for the selection and breeding of cattle and buffalo on the Asian continent. To address these recommendations, an experts meeting on Selection Criteria for Breeding Heifers was organized and held in Mymensingh, Bangladesh. The meeting was hosted by the Faculty of Veterinary Science of the Bangladesh Agricultural University (BAU) from 6 to 10 February 2006. It was attended by six foreign experts and two local experts, and was supported by the technical officer of RAS/5/044. The experts from countries participating in RAS/5/044 gave presentations on the current state of cattle breeding in their countries and two experts working in industrialized countries within the region (New Zealand and Australia) informed the participants about the existing cattle breeding programmes in their respective countries and offered their perspectives on how similar approaches could be transferred to the Member States participating in RAS/5/044. All experts also made a field visit to a prominent dairy-producing region, to experience at first-hand some of the current programmes
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McDonald, Paul G.; Te Marvelde, Luc; Kazem, Anahita J. N.; Wright, Jonathan
Research on cooperative breeding has begun to focus on direct fitness benefits gained by helpers, particularly when individuals are unrelated to those they assist. There has been considerable interest in helping possibly operating as a signal, either to show off individual quality to potential mates
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High frequency of extra-pair paternity in an urban population of Cooper's Hawks
Rosenfield, Robert N.; Sonsthagen, Sarah A.; Stout, William C.; Talbot, Sandra L.
2015-01-01
Raptors exhibit some of the highest rates of intra-pair copulations among birds, perhaps in an attempt by males to reduce the risk of being cuckolded. Indeed, the frequency of extra-pair fertilizations reported in studies of raptors to date is relatively low (0-11.2%). Socially monogamous Cooper's Hawks (Accipiter cooperii) exhibit one of the highest copulation rates among birds, yet there are no published accounts of extra-pair copulations (or paternity). We studied a population of Cooper's Hawks in Milwaukee, Wisconsin, during three breeding seasons (2003, 2004, and 2007), examining the possible effects of age (1 yr old vs. ≥ 2 yr old), adult mass, and brood size on the frequency of extra-pair paternity (EPP). We found that 19.3% of nestlings (N = 27/140) were extra-pair young (EPY), and 34% of all broods (N = 15/44) had at least one EPY. The sires of the EPY in our study were identified for only two broods, suggesting that floater males may have engaged in extra-pair copulations with territorial females. We found that brood size was a good predictor of the occurrence of EPP (EPP) in nests, but adult mass and female age were not. To our knowledge, these possible correlates of the occurrence of EPP in raptors had not previously been investigated. Male Cooper's Hawks provide food for females during the pre-nesting period, and delivery of food is, in contrast to other raptor species, typically followed by copulation. Thus, one possible explanation of the relatively high rates of EPP in our study is that females might accept or even solicit extra-pair copulations from males other than their mates as a means of maximizing energy intake for egg production. Such behavior might be particularly likely in our study area, i.e., a food-rich urban setting with a high breeding density of Cooper's Hawks.
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Directory of Open Access Journals (Sweden)
Raúl Rosales Guzmán
2015-06-01
Full Text Available The present article contains an analysis on the possibilities offered by the cooperative sector in La Palma, which is supported by the local development initiative of breeding rabbits. This activity can be easily carried out with minimal cost and effort, and is supported by a tradition in the local population, mainly in the private sector. The proposal will allow the production of rabbit meat in order to ease the difficult situation regarding meat supply; constitute the fundamental problem of how to incorporate research conducted the cooperative sector in La Palma to development projects municipal initiative? The Group of Local Development in La Palma has a project portfolio in which many important enterprises take part, with lack of initiation on the cooperative sector, which is basic for La Palma’s and Cuba’s economy. This proposal is also sustained by the fact that all cooperatives in that territory have a great deal of resources of all kinds (human, natural, etc which will allow for a sustainable development and the improvement of life quality standards for associates and inhabitants in general. The aim of the research conducted to analyze the possibilities of the cooperative sector in the municipality of La Palma, incorporating the process of local development initiative, through a project on breeding rabbit and improve the supply of meat in the town
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Analysis of breed effects on semen traits in light horse, warmblood, and draught horse breeds.
Gottschalk, Maren; Sieme, Harald; Martinsson, Gunilla; Distl, Ottmar
2016-05-01
In the present study, systematic effects on semen quality traits were investigated in 381 stallions representing 22 breeds. All stallions were used for AI either at the Lower Saxon National Stud Celle or the North Rhine-Westphalian National Stud Warendorf. A total of 71,078 fresh semen reports of the years 2001 to 2014 were edited for analysis of gel-free volume, sperm concentration, total number of sperm, progressive motility, and total number of progressively motile sperm. Breed differences were studied for warmblood and light horse breeds of both national studs (model I) and for warmblood breeds and the draught horse breed Rhenish German Coldblood from the North Rhine-Westphalian National stud (model II) using mixed model procedures. The fixed effects of age class, year, and month of semen collection had significant influences on all semen traits in both analyses. A significant influence of the horse breed was found for all semen traits but gel-free volume in both statistical models. Comparing warmblood and light horse stallions of both national studs, we observed highest sperm concentrations, total numbers of sperm, and total numbers of progressively motile sperm in Anglo-Arabian stallions. The draught horse breed Rhenish German Coldblood had the highest least squares means for gel-free volume, whereas all other investigated semen traits were significantly lower in this breed compared to the warmblood stallions under study. The variance components among stallions within breeds were significant for all semen traits and accounted for 40% to 59% of the total variance. The between-breed-variance among stallions was not significant underlining the similar size of the random stallion effect in each of the horse breeds analyzed here. In conclusion, breed and stallion are accounting for a significant proportion of the variation in semen quality. Copyright © 2016 Elsevier Inc. All rights reserved.
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Breeding performance in the Italian chicken breed Mericanel della Brianza
Directory of Open Access Journals (Sweden)
Stefano P. Marelli
2010-11-01
Full Text Available In Italy, 90 local avian breeds were described, the majority (61% were classified extinct and only 8.9 % still diffused. Therefore, efforts for conservation of Italian avian breeds are urgently required. The aim of this study was to record the breeding performance of the Italian breed Mericanel della Brianza and multiply a small population, in order to develop a conservation program. Fourteen females and 8 males were available at the beginning of the reproductive season in 2009 and organized in 8 families (1 male/1-2 females kept in floor pens. Birds received a photoperiod of 14L:10D and fed ad libitum. Breeding performance was recorded from March to June. Egg production and egg weight were recorded daily; eggs were set every 2 weeks and fertility, embryo mortality and hatchability were recorded. Mean egg production was 37% and mean egg weight was 34±3.49 g. High fertility values were recorded in the first three settings, from 94 to 87%, and the overall mean fertility value was 81.6%. Overall hatchability was only 49.6% due to a high proportion of dead embryos. Embryo mortality occurred mainly between day 2 and 7 of incubation and during hatch. Highest hatchability values were recorded in setting 1 and 2, 69 and 60% respectively, and a great decrease was found in the following settings. Great variations in egg production, fertility, hatchability and embryo mortality were found among families. The present results are the basic knowledge on reproductive parameters necessary to improve the reproductive efficiency of the breed within a conservation plan.
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Maan, Martine E; Seehausen, Ole; Groothuis, Ton G G
2017-01-01
Identifying the selective forces that initiate ecological speciation is a major challenge in evolutionary biology. Sensory drive has been implicated in speciation in various taxa, largely based on phenotype-environment correlations and signatures of selection in sensory genes. Here, we present a reciprocal transplant experiment revealing species differences in performance in alternative visual environments, consistent with speciation by divergent sensory drive. The closely related cichlids Pundamilia pundamilia and Pundamilia nyererei inhabit different visual environments in Lake Victoria and show associated differences in visual system properties. Mimicking the two light environments in the laboratory, we find a substantial reduction in survival of both species when reared in the other species' visual environment. This implies that the observed differences in Pundamilia color vision are indeed adaptive and substantiates the implicit assumption in sensory drive speciation models that divergent environmental selection is strong enough to drive divergence in sensory properties.
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Husemann, M; Tobler, M; McCauley, C; Ding, B; Danley, P D
2014-05-01
The cichlid fishes of Lake Malawi represent one of the most diverse adaptive radiations of vertebrates known. Among the rock-dwelling cichlids (mbuna), closely related sympatric congeners possess similar trophic morphologies (i.e. cranial and jaw structures), defend overlapping or adjacent territories, but can be easily distinguished based on male nuptial coloration. The apparent morphological similarity of congeners, however, leads to an ecological conundrum: theory predicts that ecological competition should lead to competitive exclusion. Hence, we hypothesized that slight, yet significant, ecological differences accompanied the divergence in sexual signals and that the divergence of ecological and sexual traits is correlated. To evaluate this hypothesis, we quantified body shape, a trait of known ecological importance, in populations of Maylandia zebra, a barred, widespread mbuna, and several sympatric nonbarred congeners. We found that the barred populations differ in body shape from their nonbarred sympatric congeners and that the direction of shape differences was consistent across all barred vs. nonbarred comparisons. Barred populations are generally deeper bodied which may be an adaptation to the structurally complex habitat they prefer, whereas the nonbarred species have a more fusiform body shape, which may be adaptive in their more open microhabitat. Furthermore, M. zebra populations sympatric with nonbarred congeners differ from populations where the nonbarred phenotype is absent and occupy less morphospace, indicating potential ecological character displacement. Mitochondrial DNA as well as published AFLP data indicated that the nonbarred populations are not monophyletic and therefore may have evolved multiple times independently. Overall our data suggest that the evolution of coloration and body shape may be coupled as a result of correlational selection. We hypothesize that correlated evolution of sexually selected and ecological traits may have
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Moravec, F; Scholz, T; Mendoza Franco, E
1995-01-01
Capillaria (Hepatocapillaria) cichlasomae sp. n., parasitic in the liver of the cichlid Cichlasoma urophthalmus (Günther) from a small freshwater lake ("aguada") Xpoc in Yucatan, Mexico, is described. The parasite is characterized mainly by its small body size (male 1.8 mm, female 4.5 mm), the structure of the stichosome (markedly short stichocytes in one row) and the male (the presence of a pair of small subventral postanal papillae) and female (anus distinctly subterminal) caudal ends, and by the size and structure of the spicule (spicule 0.068-0.085 mm long, with marked transverse grooves on surface) and eggs (size 0.053-0.058 x 0.023 mm, with protruding polar plugs). This is the second known Capillaria species from the liver of fish and the first one from the liver of a freshwater fish.
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African Journals Online (AJOL)
Received 31 August 1996; accepted 20 March /998. Mitochondrial DNA cleavage patterns from representative animals of the Afrikaner and Nguni sanga cattle breeds, indigenous to Southern Africa, were compared to the mitochondrial DNA cleavage patterns of the Brahman (zebu) and the Jersey. (taurine) cattle breeds.
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DEFF Research Database (Denmark)
Mark, Thomas; Sandøe, Peter
2010-01-01
the thoughts of breeders and other stakeholders on how to best make use of genomic breeding in the future. Intensive breeding has played a major role in securing dramatic increases in milk yield since the Second World War. Until recently, the main focus in dairy cattle breeding was on production traits...... it less accountable to the concern of private farmers for the welfare of their animals. It is argued that there is a need to mobilise a wide range of stakeholders to monitor developments and maintain pressure on breeding companies so that they are aware of the need to take precautionary measures to avoid...
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Male mate choice scales female ornament allometry in a cichlid fish
Directory of Open Access Journals (Sweden)
Kullmann Harald
2010-10-01
Full Text Available Abstract Background Studies addressing the adaptive significance of female ornamentation have gained ground recently. However, the expression of female ornaments in relation to body size, known as trait allometry, still remains unexplored. Here, we investigated the allometry of a conspicuous female ornament in Pelvicachromis taeniatus, a biparental cichlid that shows mutual mate choice and ornamentation. Females feature an eye-catching pelvic fin greatly differing from that of males. Results We show that allometry of the female pelvic fin is scaled more positively in comparison to other fins. The pelvic fin exhibits isometry, whereas the other fins (except the caudal fin show negative allometry. The size of the pelvic fin might be exaggerated by male choice because males prefer female stimuli that show a larger extension of the trait. Female pelvic fin size is correlated with individual condition, suggesting that males can assess direct and indirect benefits. Conclusions The absence of positive ornament allometry might be a result of sexual selection constricted by natural selection: fins are related to locomotion and thus may be subject to viability selection. Our study provides evidence that male mate choice might scale the expression of a female sexual ornament, and therefore has implications for the understanding of the relationship of female sexual traits with body size in species with conventional sex-roles.
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Across Breed QTL Detection and Genomic Prediction in French and Danish Dairy Cattle Breeds
DEFF Research Database (Denmark)
van den Berg, Irene; Guldbrandtsen, Bernt; Hozé, C
Our objective was to investigate the potential benefits of using sequence data to improve across breed genomic prediction, using data from five French and Danish dairy cattle breeds. First, QTL for protein yield were detected using high density genotypes. Part of the QTL detected within breed was...
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Reproductive-tactic-specific variation in sperm swimming speeds in a shell-brooding cichlid.
Fitzpatrick, J L; Desjardins, J K; Milligan, N; Montgomerie, R; Balshine, S
2007-08-01
Theory predicts that males experiencing elevated levels of sperm competition will invest more in gonads and produce faster-swimming sperm. Although there is ample evidence in support of the first prediction, few studies have examined sperm swimming speed in relation to sperm competition. In this study, we tested these predictions from sperm competition theory by examining sperm characteristics in Telmatochromis vittatus, a small shell-brooding cichlid fish endemic to Lake Tanganyika. Males exhibit four different reproductive tactics: pirate, territorial, satellite, and sneaker. Pirate males temporarily displace all other competing males from a shell nest, whereas sneaker males always release sperm in the presence of territorial and satellite males. Due to the fact that sneakers spawn in the presence of another male, sneakers face the highest levels of sperm competition and pirates the lowest, whereas satellites and territorials experience intermediate levels. In accordance with predictions, sperm from sneakers swam faster than sperm from males adopting the other reproductive tactics, whereas sperm from pirates was slowest. Interestingly, we were unable to detect any variation in sperm tail length among these reproductive tactics. Thus, sperm competition appears to have influenced sperm energetics in this species without having any influence on sperm size.
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International Nuclear Information System (INIS)
Hollenberg, G.W.; Johnson, C.E.; Abdou, M.
1984-03-01
Tritium breeding materials are essential to the operation of D-T fusion facilities. Both of the present options - solid ceramic breeding materials and liquid metal materials are reviewed with emphasis not only on their attractive features but also on critical materials issues which must be resolved
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International Nuclear Information System (INIS)
Hollenberg, G.W.; Johnson, C.E.; Abdou, M.A.
1984-01-01
Tritium breeding materials are essential to the operation of D-T fusion facilities. Both of the present options - solid ceramic breeding materials and liquid metal materials are reviewed with emphasis not only on their attractive features but also on critical materials issues which must be resolved
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The influence of cross-breeding Zlotnicka Spotted native breed sows ...
African Journals Online (AJOL)
To sum up, it is possible to say that the raw meat of Zlotnicka Spotted pigs and their cross-breeds with Duroc and Polish Large White breeds is characterised by good quality and because of its considerable intramuscular fat content, it has a high culinary and processing value, especially for ripening products. Key words: Pigs ...
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Genetic diversity of dog breeds: within-breed diversity comparing genealogical and molecular data.
Leroy, G; Verrier, E; Meriaux, J C; Rognon, X
2009-06-01
The genetic diversity of 61 dog breeds raised in France was investigated. Genealogical analyses were performed on the pedigree file of the French kennel club. A total of 1514 dogs were also genotyped using 21 microsatellite markers. For animals born from 2001 to 2005, the average coefficient of inbreeding ranged from 0.2% to 8.8% and the effective number of ancestors ranged from 9 to 209, according to the breed. The mean value of heterozygosity was 0.62 over all breeds (range 0.37-0.77). At the breed level, few correlations were found between genealogical and molecular parameters. Kinship coefficients and individual similarity estimators were, however, significantly correlated, with the best mean correlation being found for the Lynch & Ritland estimator (r = 0.43). According to both approaches, it was concluded that special efforts should be made to maintain diversity for three breeds, namely the Berger des Pyrénées, Braque Saint-Germain and Bull Terrier.
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Bergmann, Gaddy T; Motta, Philip J
2004-04-01
Larval nematodes that parasitize the Mayan cichlid fish 'Cichlasoma (Nandopsis)' urophthalmus (Günther 1862) in southern Florida were identified as Contracaecum spp. (Nematoda: Anisakidae, Anisakinae). The objective of this study was to determine whether infection intensity and prevalence of these parasites differ between a brackish water and freshwater habitat or through ontogeny in the freshwater habitat only. The nematodes were removed from the abdominal cavity of the fishes and counted. Infection intensity was compared between habitats using analysis of covariance and evaluated through ontogeny using Spearman rank order correlation. Prevalence was compared between habitats and between adults and juveniles from the freshwater habitat using a z-test. Although infection intensity did not differ between habitats, infection prevalence was greater at the freshwater site (FWS). Both the prevalence and intensity of nematode infection increased through ontogeny at the FWS, and no nematode was found in fishes that were smaller than 93 mm standard length. Thus, the parasites appear to accumulate during the lifetime of the fishes.
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2012-01-01
Background The Nile tilapia (Oreochromis niloticus) is the second most farmed fish species worldwide. It is also an important model for studies of fish physiology, particularly because of its broad tolerance to an array of environments. It is a good model to study evolutionary mechanisms in vertebrates, because of its close relationship to haplochromine cichlids, which have undergone rapid speciation in East Africa. The existing genomic resources for Nile tilapia include a genetic map, BAC end sequences and ESTs, but comparative genome analysis and maps of quantitative trait loci (QTL) are still limited. Results We have constructed a high-resolution radiation hybrid (RH) panel for the Nile tilapia and genotyped 1358 markers consisting of 850 genes, 82 markers corresponding to BAC end sequences, 154 microsatellites and 272 single nucleotide polymorphisms (SNPs). From these, 1296 markers could be associated in 81 RH groups, while 62 were not linked. The total size of the RH map is 34,084 cR3500 and 937,310 kb. It covers 88% of the entire genome with an estimated inter-marker distance of 742 Kb. Mapping of microsatellites enabled integration to the genetic map. We have merged LG8 and LG24 into a single linkage group, and confirmed that LG16-LG21 are also merged. The orientation and association of RH groups to each chromosome and LG was confirmed by chromosomal in situ hybridizations (FISH) of 55 BACs. Fifty RH groups were localized on the 22 chromosomes while 31 remained small orphan groups. Synteny relationships were determined between Nile tilapia, stickleback, medaka and pufferfish. Conclusion The RH map and associated FISH map provide a valuable gene-ordered resource for gene mapping and QTL studies. All genetic linkage groups with their corresponding RH groups now have a corresponding chromosome which can be identified in the karyotype. Placement of conserved segments indicated that multiple inter-chromosomal rearrangements have occurred between Nile tilapia
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Breeds in danger of extintion and biodiversity
A. Blasco
2008-01-01
Some arguments currently used to support breed conservation are examined. The central point is that we cannot conserve all breeds because we do not have financial resources enough to keep everything (mainly in developing countries) and in many cases we do not have special reasons to conserve breeds. A breed is a human product and it should not be confused with specie. A breed can be generated or transformed. We can create synthetic breeds with the best characteristics of several breeds. Selec...
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Mutations in plant breeding: a glance back and a look forward
International Nuclear Information System (INIS)
Gustafsson, A.
1975-01-01
This brief retrospect of previous shortcomings and procedures really indicates the need for a better co-ordination and co-operation in plant breeding. We now know which mutagens are essential in practical mutation work, and we include radiations as well as chemicals. We now know that there is no principal difference between natural and induced variation. We can easily induce mutational events covering the gap between gross chromosomal rearrangements and DNA-base substitutions. We also know that induced variation may in the future fill and replace the loss of natural variability, or may even extend the limits of variation. We know that mutation and recombination--as evidenced, for instance, by the successful work in barley--will be united into routine procedures, also leading to new breakthroughs in plant improvement. Moreover, ingenious techniques of mass testing are under way, combining traditional and prospective ideas. The mutation method has come to stay, not alone but with gene recombination, with heterosis and with polyploidy. We say that the present is the past's future. To glance back is then to look forward; failures give rise to progress. A synthesis of breeding methods is around the corner
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Plant mutation breeding and application of isotopic tracer in Chinese agriculture
International Nuclear Information System (INIS)
Liang Qu
1993-03-01
The progress and achievements made in plant mutation breeding and application of isotopic tracer in Chinese agriculture are outlined. Plant mutation breeding is well developed not only in improvement of crops but also in methodology of mutation induction. More than 325 mutant varieties and hundreds of various valuable mutants of 29 different species have been obtained. The mutant cultivars released have covered more than 10 million hectares in total area. The systematic studies on methodology such as techniques for mutagenic treatment, development of various mutagens, screening and selecting techniques of mutation etc. have been carried out in China. The techniques of radioisotopic tracer used in many research fields are described. Application of isotopic tracer in studies of fertilization and plant nutrition, environment protection, nitrogen-fixation, animal production and diagnosis of diseases, and so on, have made great achievements and benefits in China. Many kinds of labelled compounds, especially of labelled agro-chemicals have been synthesized in the Institute for Application of Atomic Energy (IAAE). Chinese Academy of Agricultural Sciences (CAAS). The proposals for the region cooperation in Asia on application of atomic energy in agriculture are included
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Genomics-assisted breeding in fruit trees.
Iwata, Hiroyoshi; Minamikawa, Mai F; Kajiya-Kanegae, Hiromi; Ishimori, Motoyuki; Hayashi, Takeshi
2016-01-01
Recent advancements in genomic analysis technologies have opened up new avenues to promote the efficiency of plant breeding. Novel genomics-based approaches for plant breeding and genetics research, such as genome-wide association studies (GWAS) and genomic selection (GS), are useful, especially in fruit tree breeding. The breeding of fruit trees is hindered by their long generation time, large plant size, long juvenile phase, and the necessity to wait for the physiological maturity of the plant to assess the marketable product (fruit). In this article, we describe the potential of genomics-assisted breeding, which uses these novel genomics-based approaches, to break through these barriers in conventional fruit tree breeding. We first introduce the molecular marker systems and whole-genome sequence data that are available for fruit tree breeding. Next we introduce the statistical methods for biparental linkage and quantitative trait locus (QTL) mapping as well as GWAS and GS. We then review QTL mapping, GWAS, and GS studies conducted on fruit trees. We also review novel technologies for rapid generation advancement. Finally, we note the future prospects of genomics-assisted fruit tree breeding and problems that need to be overcome in the breeding.
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Plant breeding and genetics newsletter. No. 9
Energy Technology Data Exchange (ETDEWEB)
NONE
2002-07-01
Course 'Mutant germplasm characterization using molecular markers. A Manual'. The manual is now in print and will be published and distributed in August 2002. The Technical Co-operation activities concentrate on evaluation of new project proposals for the implementation cycle 2004-2005 and on organization of two new regional projects in Asia: 'Enhancement of genetic diversity in food pulses and oil crops and establishment of mutant germplasm network' and 'Elimination of micronutrient malnutrition in East Asia and the Pacific'. Under the Regional AFRA project a workshop was held in Cameroon to review mutation methodology and results of experiments on genetic improvement of neglected African crops. The activities of the Plant Breeding Unit, Seibersdorf concentrated on the use of cell suspensions for the induction and selection of mutants in banana and on establishing of DNA fingerprinting service. Also, work on isolation and characterisation of rice mutants with salinity tolerance was continued.
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Plant breeding and genetics newsletter. No. 9
International Nuclear Information System (INIS)
2002-07-01
Course 'Mutant germplasm characterization using molecular markers. A Manual'. The manual is now in print and will be published and distributed in August 2002. The Technical Co-operation activities concentrate on evaluation of new project proposals for the implementation cycle 2004-2005 and on organization of two new regional projects in Asia: 'Enhancement of genetic diversity in food pulses and oil crops and establishment of mutant germplasm network' and 'Elimination of micronutrient malnutrition in East Asia and the Pacific'. Under the Regional AFRA project a workshop was held in Cameroon to review mutation methodology and results of experiments on genetic improvement of neglected African crops. The activities of the Plant Breeding Unit, Seibersdorf concentrated on the use of cell suspensions for the induction and selection of mutants in banana and on establishing of DNA fingerprinting service. Also, work on isolation and characterisation of rice mutants with salinity tolerance was continued
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Phillips, Tim
2018-02-01
Evolutionary theory predicts competition in nature yet altruistic and cooperative behaviour appears to reduce the ability to compete in order to help others compete better. This evolutionary puzzle is usually explained by kin selection where close relatives perform altruistic and cooperative acts to help each other and by reciprocity theory (i.e. direct, indirect and generalized reciprocity) among non-kin. Here, it is proposed that the concepts of asymmetry and symmetry in power and dominance are critical if we are ever to resolve the puzzle of altruism and cooperation towards non-kin. Asymmetry in power and dominance is likely to emerge under competition in nature as individuals strive to gain greater access to the scarce resources needed to survive and reproduce successfully. Yet asymmetric power presents serious problems for reciprocity theory in that a dominant individual faces a temptation to cheat in interactions with subordinates that is likely to far outweigh any individual selective benefits gained through reciprocal mechanisms. Furthermore, action taken by subordinates to deter non-reciprocation by dominants is likely to prove prohibitively costly to their fitness, making successful enforcement of reciprocal mechanisms unlikely. It is also argued here that many apparently puzzling forms of cooperation observed in nature (e.g. cooperative breeding in which unrelated subordinates help dominants to breed) might be best explained by asymmetry in power and dominance. Once it is recognized that individuals in these cooperative interactions are subject to the constraints and opportunities imposed on them by asymmetric power then they can be seen as pursuing a 'least bad' strategy to promote individual fitness - one that is nevertheless consistent with evolutionary theory. The concept of symmetric power also provides important insights. It can inhibit reciprocal mechanisms in the sense that symmetric power makes it easier for a cheat to appropriate common
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Heberlein, Marianne T E; Turner, Dennis C; Manser, Marta B
2017-02-01
Attending to the perception of others may help individuals gaining information from conspecifics, or help in competitive situations. Dogs (Canis familiaris) are attentive to humans' signals and their attentional state. We investigated whether dogs of different breed groups differ in their ability to pay attention to human's perception, first according to the genetic relatedness between dog breeds, and second according to working style differences. Once dogs had learned to leave forbidden food on the floor, they were confronted with 2 food items to which only they had unrestricted visual access. The owners saw either none or 1 food item through a transparent barrier. Our results showed that dogs pay attention to the perception of humans, whereby differences between breed groups became obvious. Within different genetic groups, ancient and hunting type dogs performed similarly, they were more attentive to their owners' perception than shepherd and the mastiff type dogs. When comparing dogs classified according to their working style, independent workers and family dogs were attentive to the owner's perception, while cooperative workers seemed not. The dogs' choice could not be explained by a general or training induced preference for eating behind an opaque screen, or by an influence of the owner's possible intention to prevent the dog from taking the food item he could see. Our study confirms that dogs are attentive/sensitive to human's perception, but genetic and working style differences among the breeds, as well as dog sport experiences explain part of the variation seen in their performance. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
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Genomic analyses of modern dog breeds.
Parker, Heidi G
2012-02-01
A rose may be a rose by any other name, but when you call a dog a poodle it becomes a very different animal than if you call it a bulldog. Both the poodle and the bulldog are examples of dog breeds of which there are >400 recognized worldwide. Breed creation has played a significant role in shaping the modern dog from the length of his leg to the cadence of his bark. The selection and line-breeding required to maintain a breed has also reshaped the genome of the dog, resulting in a unique genetic pattern for each breed. The breed-based population structure combined with extensive morphologic variation and shared human environments have made the dog a popular model for mapping both simple and complex traits and diseases. In order to obtain the most benefit from the dog as a genetic system, it is necessary to understand the effect structured breeding has had on the genome of the species. That is best achieved by looking at genomic analyses of the breeds, their histories, and their relationships to each other.
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Müllner, Antje
2005-01-01
The hoatzin (Opisthocomus hoazin) is an enigmatic bird that lives in the riparian lowlands of northern South America. Among its peculiar attributes are 1) microbial foregut fermentation, unique in birds, to convert plant cellulose in the foliage which it consumes into simple sugars, 2) an ongoing debate about the puzzling taxonomic position, although a relationship to the Cuculiformes appears likely, 3) adaptive wing claws in the young which are used for climbing, and 4) co-operative breeding...
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Sire breed and breed genotype of dam effects in crossbreeding beef ...
African Journals Online (AJOL)
Cows bred to Afrikaner bulls were less (P < 0.05) productive than cows bred to other Bos taurus sires. An increase in proportion Afrikaner breeding in dam resulted in longer calving intervals and a decline in cow productivity, but these differences were not always significant. A breeding strategy for the retainment of superior ...
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Influence of cross-breeding of native breed sows of Zlotnicka spotted ...
African Journals Online (AJOL)
The aim of this study was the estimation of the cross-breeding influence of Zlotnicka spotted sows with boars of polish large white and Duroc breeds on carcass traits of fatteners. 50 pigs were divided into four groups: Zlotnicka spotted (ZS), Zlotnicka spotted x polish large white (ZS x PLW), Zlotnicka spotted x Duroc (ZS x D) ...
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Partial characterisation of digestive proteases of the Mayan cichlid Cichlasoma urophthalmus.
Cuenca-Soria, C A; Álvarez-González, C A; Ortiz-Galindo, J L; Nolasco-Soria, H; Tovar-Ramírez, D; Guerrero-Zárate, R; Castillo-Domínguez, A; Perera-García, M A; Hernández-Gómez, R; Gisbert, E
2014-06-01
The characterisation of digestive proteases in native freshwater fish such as the Mayan cichlid Cichlasoma urophthalmus provides scientific elements that may be used to design balanced feed that matches with the digestive capacity of the fish. The purpose of this study was to characterise the digestive proteases, including the effect of the pH and the temperature on enzyme activity and stability, as well as the effect of inhibitors using multienzymatic extracts of the stomach and intestine of C. urophthalmus juveniles. Results showed that the optimum activities of the acid and alkaline proteases occurred at pH values of 3 and 9, respectively, whereas their optimum temperatures were 55 and 65 °C, respectively. The acid proteases were most stable at pH values of 2–3 and at temperatures of 35–45 °C, whereas the alkaline proteases were most stable at pH values of 6–9 and at 25–55 °C. The inhibition assays recorded a residual activity of 4% with pepstatin A for the acid proteases. The inhibition of the alkaline proteases was greater than 80% with TPCK, TLCK, EDTA and ovalbumin, and of 60 and 43.8% with PMSF and SBT1, respectively. The results obtained in this study make it possible to state that C. urophthalmus has a sufficiently complete digestive enzyme machinery to degrade food items characteristic of an omnivorous fish species, although specimens showed a tendency to carnivory.
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ROOT VEGETABLES, BREEDING TRENDS, RESULTS
Directory of Open Access Journals (Sweden)
M. I. Fedorova
2017-01-01
Full Text Available The main advantage of root vegetables is their unique specificity and high economic importance. The benefits and medicinal properties of root vegetables being highly demanded by the market requirements to the commodity are highlighted in the article. The main directions of breeding program for root vegetable crops, including species of Apiaceae family with carrot, parsnips; Chenopodioideae family with red beet; Brassicaceae family with radish, Daikon, Raphanus sativus L. var. lobo Sazonova & Stank, turnip and rutabaga. Initial breeding accessions of carrot, red beet, radish, Daikon, Raphanus sativus L. var. lobo Sazonova & Stank, turnip and rutabaga have been selected out to be used for breeding program for heterosis. The mf and ms breeding lines were developed, and with the use of them the new gene pool was created. Variety supporting breeding program and methods were also proposed.
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Gizaw, S.; Komen, J.; Windig, J.J.; Hanotte, O.; Arendonk, van J.A.M.
2008-01-01
Prioritizing livestock breeds for conservation needs to incorporate both genetic and non-genetic aspects important for the survival of the breeds. Here, we apply a maximum-utility-strategy to prioritize 14 traditional Ethiopian sheep breeds based on their threat status, contributions to farmer
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Ito, Munehiko H; Yamaguchi, Motoomi; Kutsukake, Nobuyuki
2018-01-31
Conflict management consists of social behaviours that reduce the costs of conflict among group members. Redirected aggression-that is, when a recently attacked individual attacks a third party immediately after the original aggression-is considered a conflict management tactic, as it may reduce the victim's probability of being the object of further aggression. Redirected aggression has been reported in many vertebrates, but few quantitative studies have been conducted on this behaviour in fishes. We examined the function of redirected aggression in Julidochromis regani , a social cichlid fish. Behavioural experiments showed that redirected aggression functioned to divert the original aggressor's attention towards a third party and to pre-empt an attack towards the victim by the third-party individual, specifically among females. We found, however, that redirected aggression did not delay the recurrence of aggression by the original aggressor. These results suggest that a primary function of redirected aggression is to maintain the dominance of its actor against a subordinate occupying an adjacent rank. This study provides, to our knowledge, the first evidence that redirected aggression functions to manage conflict in social fish. © 2018 The Author(s).
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DEFF Research Database (Denmark)
Campbell, M.L.H.; Sandøe, Peter
2015-01-01
and identifies areas in which data is lacking. We suggest that all methods of horse breeding are associated with potential welfare problems, but also that the judicious use of ARTs can sometimes help to address those problems. We discuss how negative welfare effects could be identified and limited and how...... positive welfare effects associated with breeding might be maximised. Further studies are needed to establish an evidence base about how stressful or painful various breeding procedures are for the animals involved, and what the lifetime welfare implications of ARTs are for future animal generations....
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Directory of Open Access Journals (Sweden)
Kristaq Kume
2012-07-01
Full Text Available About 950,000 goats, farmed mostly in hilly and mountainous areas of Albania, contribute about 8% of the country’s total milk production. In order to increase milk production, farmers are currently using crosses of the local goat breed with exotic breeds, mainly the Alpine breed from France. This study examines milk production data of first lactation from 45 goats of the local breed, 82 goats of the Alpine breed and 58 F1 crosses (♂Alpine breed x ♀local breed. The goats were kept on small-scale farms according to the traditional Albanian system. Milking was carried out in the morning and evening. Kids were weaned at 65 days of age after which milking started. Milk yield was recorded twice with a 15-day interval between the two readings. Total milk yield was calculated using the Fleischmann method. The F1 goats produced 37.8 kg more milk than local breed goats although the lactation length (P<0.05 of F1 goats was six days shorter compared to that of local breed goats (P<0.05. Analysis of variance showed a highly significant effect (P<0.01 of the genotype factor on milk production. The average Cappio-Borlino curves of three genotypes indicated that the lactation curves of local breed and F1 crosses were similar. Although the F1 cross goats had 50% of their genomes from a genetically improved breed they were still able to deal with the difficult conditions that characterize the traditional extensive farming systems in Albania. Breeding pure Alpine breed or its crosses with the local goat breed improved milk production in an extensive traditional system.
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The influence of stress hormones and aggression on cooperative behaviour in subordinate meerkats.
Dantzer, Ben; Goncalves, Ines Braga; Spence-Jones, Helen C; Bennett, Nigel C; Heistermann, Michael; Ganswindt, Andre; Dubuc, Constance; Gaynor, David; Manser, Marta B; Clutton-Brock, Tim H
2017-09-27
In cooperative breeders, aggression from dominant breeders directed at subordinates may raise subordinate stress hormone (glucocorticoid) concentrations. This may benefit dominants by suppressing subordinate reproduction but it is uncertain whether aggression from dominants can elevate subordinate cooperative behaviour, or how resulting changes in subordinate glucocorticoid concentrations affect their cooperative behaviour. We show here that the effects of manipulating glucocorticoid concentrations in wild meerkats ( Suricata suricatta ) on cooperative behaviour varied between cooperative activities as well as between the sexes. Subordinates of both sexes treated with a glucocorticoid receptor antagonist (mifepristone) exhibited significantly more pup protection behaviour (babysitting) compared to those treated with glucocorticoids (cortisol) or controls. Females treated with mifepristone had a higher probability of exhibiting pup food provisioning (pup-feeding) compared to those treated with cortisol. In males, there were no treatment effects on the probability of pup-feeding, but those treated with cortisol gave a higher proportion of the food they found to pups than those treated with mifepristone. Using 19 years of behavioural data, we also show that dominant females did not increase the frequency with which they directed aggression at subordinates at times when the need for assistance was highest. Our results suggest that it is unlikely that dominant females manipulate the cooperative behaviour of subordinates through the effects of aggression on their glucocorticoid levels and that the function of aggression directed at subordinates is probably to reduce the probability they will breed. © 2017 The Author(s).
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Efficient Breeding by Genomic Mating.
Akdemir, Deniz; Sánchez, Julio I
2016-01-01
Selection in breeding programs can be done by using phenotypes (phenotypic selection), pedigree relationship (breeding value selection) or molecular markers (marker assisted selection or genomic selection). All these methods are based on truncation selection, focusing on the best performance of parents before mating. In this article we proposed an approach to breeding, named genomic mating, which focuses on mating instead of truncation selection. Genomic mating uses information in a similar fashion to genomic selection but includes information on complementation of parents to be mated. Following the efficiency frontier surface, genomic mating uses concepts of estimated breeding values, risk (usefulness) and coefficient of ancestry to optimize mating between parents. We used a genetic algorithm to find solutions to this optimization problem and the results from our simulations comparing genomic selection, phenotypic selection and the mating approach indicate that current approach for breeding complex traits is more favorable than phenotypic and genomic selection. Genomic mating is similar to genomic selection in terms of estimating marker effects, but in genomic mating the genetic information and the estimated marker effects are used to decide which genotypes should be crossed to obtain the next breeding population.
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Directory of Open Access Journals (Sweden)
Ehsan Pashay Ahi
2017-01-01
Full Text Available Fish color patterns are among the most diverse phenotypic traits found in the animal kingdom. Understanding the molecular and cellular mechanisms that control in chromatophore distribution and pigmentation underlying this diversity is a major goal in developmental and evolutionary biology, which has predominantly been pursued in the zebrafish model system. Here, we apply results from zebrafish work to study a naturally occurring color pattern phenotype in the fins of an African cichlid species from Lake Tanganyika. The cichlid fish Neolamprologus meeli displays a distinct dorsal color pattern, with black and white stripes along the edges of the dorsal fin and of the dorsal half of the caudal fin, corresponding with differences in melanophore density. To elucidate the molecular mechanisms controlling the differences in dorsal and ventral color patterning in the fins, we quantitatively assessed the expression of 15 candidate target genes involved in adult zebrafish pigmentation and stripe formation. For reference gene validation, we screened the expression stability of seven widely expressed genes across the investigated tissue samples and identified tbp as appropriate reference. Relative expression levels of the candidate target genes were compared between the dorsal, striped fin regions and the corresponding uniform, grey-colored regions in the anal and ventral caudal fin. Dorso-ventral expression differences, with elevated levels in both white and black stripes, were observed in two genes, the melanosome protein coding gene pmel and in igsf11, which affects melanophore adhesion, migration and survival. Next, we predicted potential shared upstream regulators of pmel and igsf11. Testing the expression patterns of six predicted transcriptions factors revealed dorso-ventral expression difference of irf1 and significant, negative expression correlation of irf1 with both pmel and igsf11. Based on these results, we propose pmel, igsf11 and irf1 as
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A computational approach to animal breeding.
Berger-Wolf, Tanya Y; Moore, Cristopher; Saia, Jared
2007-02-07
We propose a computational model of mating strategies for controlled animal breeding programs. A mating strategy in a controlled breeding program is a heuristic with some optimization criteria as a goal. Thus, it is appropriate to use the computational tools available for analysis of optimization heuristics. In this paper, we propose the first discrete model of the controlled animal breeding problem and analyse heuristics for two possible objectives: (1) breeding for maximum diversity and (2) breeding a target individual. These two goals are representative of conservation biology and agricultural livestock management, respectively. We evaluate several mating strategies and provide upper and lower bounds for the expected number of matings. While the population parameters may vary and can change the actual number of matings for a particular strategy, the order of magnitude of the number of expected matings and the relative competitiveness of the mating heuristics remains the same. Thus, our simple discrete model of the animal breeding problem provides a novel viable and robust approach to designing and comparing breeding strategies in captive populations.
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Directory of Open Access Journals (Sweden)
Małgorzata Pilot
2016-08-01
Full Text Available Domesticated species are often composed of distinct populations differing in the character and strength of artificial and natural selection pressures, providing a valuable model to study adaptation. In contrast to pure-breed dogs that constitute artificially maintained inbred lines, free-ranging dogs are typically free-breeding, i.e., unrestrained in mate choice. Many traits in free-breeding dogs (FBDs may be under similar natural and sexual selection conditions to wild canids, while relaxation of sexual selection is expected in pure-breed dogs. We used a Bayesian approach with strict false-positive control criteria to identify FST-outlier SNPs between FBDs and either European or East Asian breeds, based on 167,989 autosomal SNPs. By identifying outlier SNPs located within coding genes, we found four candidate genes under diversifying selection shared by these two comparisons. Three of them are associated with the Hedgehog (HH signaling pathway regulating vertebrate morphogenesis. A comparison between FBDs and East Asian breeds also revealed diversifying selection on the BBS6 gene, which was earlier shown to cause snout shortening and dental crowding via disrupted HH signaling. Our results suggest that relaxation of natural and sexual selection in pure-breed dogs as opposed to FBDs could have led to mild changes in regulation of the HH signaling pathway. HH inhibits adhesion and the migration of neural crest cells from the neural tube, and minor deficits of these cells during embryonic development have been proposed as the underlying cause of “domestication syndrome.” This suggests that the process of breed formation involved the same genetic and developmental pathways as the process of domestication.
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Breeds in danger of extintion and biodiversity
Directory of Open Access Journals (Sweden)
A. Blasco
2008-07-01
Full Text Available Some arguments currently used to support breed conservation are examined. The central point is that we cannot conserve all breeds because we do not have financial resources enough to keep everything (mainly in developing countries and in many cases we do not have special reasons to conserve breeds. A breed is a human product and it should not be confused with specie. A breed can be generated or transformed. We can create synthetic breeds with the best characteristics of several breeds. Selection is not exhausting genetic variability (there are several experiments showing that, and genetic variability within breeds is large. We need reasons to keep breeds in danger in extinction. A breed is a tool, and we can decide to keep it when it is useful because it is specially adapted to some environments (although in this case it should not be in danger of extinction, it can be useful in crossbreeding to shorten the way of obtaining response to selection, or it has some extreme values for traits that may be useful in the future (in this case we have to define clearly which traits and how we expect the future to be. We can add cultural reasons when we have money enough to spend in culture.
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Genomics-assisted breeding in fruit trees
Iwata, Hiroyoshi; Minamikawa, Mai F.; Kajiya-Kanegae, Hiromi; Ishimori, Motoyuki; Hayashi, Takeshi
2016-01-01
Recent advancements in genomic analysis technologies have opened up new avenues to promote the efficiency of plant breeding. Novel genomics-based approaches for plant breeding and genetics research, such as genome-wide association studies (GWAS) and genomic selection (GS), are useful, especially in fruit tree breeding. The breeding of fruit trees is hindered by their long generation time, large plant size, long juvenile phase, and the necessity to wait for the physiological maturity of the pl...
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Phocas, F; Belloc, C; Bidanel, J; Delaby, L; Dourmad, J Y; Dumont, B; Ezanno, P; Fortun-Lamothe, L; Foucras, G; Frappat, B; González-García, E; Hazard, D; Larzul, C; Lubac, S; Mignon-Grasteau, S; Moreno, C R; Tixier-Boichard, M; Brochard, M
2016-11-01
Agroecology uses ecological processes and local resources rather than chemical inputs to develop productive and resilient livestock and crop production systems. In this context, breeding innovations are necessary to obtain animals that are both productive and adapted to a broad range of local contexts and diversity of systems. Breeding strategies to promote agroecological systems are similar for different animal species. However, current practices differ regarding the breeding of ruminants, pigs and poultry. Ruminant breeding is still an open system where farmers continue to choose their own breeds and strategies. Conversely, pig and poultry breeding is more or less the exclusive domain of international breeding companies which supply farmers with hybrid animals. Innovations in breeding strategies must therefore be adapted to the different species. In developed countries, reorienting current breeding programmes seems to be more effective than developing programmes dedicated to agroecological systems that will struggle to be really effective because of the small size of the populations currently concerned by such systems. Particular attention needs to be paid to determining the respective usefulness of cross-breeding v. straight breeding strategies of well-adapted local breeds. While cross-breeding may offer some immediate benefits in terms of improving certain traits that enable the animals to adapt well to local environmental conditions, it may be difficult to sustain these benefits in the longer term and could also induce an important loss of genetic diversity if the initial pure-bred populations are no longer produced. As well as supporting the value of within-breed diversity, we must preserve between-breed diversity in order to maintain numerous options for adaptation to a variety of production environments and contexts. This may involve specific public policies to maintain and characterize local breeds (in terms of both phenotypes and genotypes), which could
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Breeding phenology of African Black Oystercatchers Haematopus ...
African Journals Online (AJOL)
The timing of the start and duration of breeding and the effect of these on breeding productivity were analysed for African Black Oystercatchers Haematopus moquini on Robben Island, South Africa, over three breeding seasons from 2001 to 2004. African Black Oystercatchers have a long breeding season, from November ...
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Selective breeding in organic dairy production
Nauta, W.J.
2009-01-01
Organic dairy farming started to take off in the early 1990s, when the European Union laid down organic standards for animal production. Until now, however, only incidental steps have been taken towards organic breeding and organic farmers mainly use breeding stock from conventional breeding
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Fouw, de Jimmy; Bom, Roeland A.; Klaassen, Raymond H.G.; Müskens, Gerard J.D.M.; Vries, de Peter P.; Popov, Igor Yu; Kokorev, Yakov I.; Ebbinge, Bart; Nolet, Bart A.
2016-01-01
Breeding success of many Arctic-breeding bird populations varies with lemming cycles due to prey switching behavior of generalist predators. Several bird species breed on islands to escape from generalist predators like Arctic fox Vulpes lagopus, but little is known about how these species
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Genetic analysis of three South African horse breeds
Directory of Open Access Journals (Sweden)
E.G. Cothran
1998-07-01
Full Text Available Genetic variability at 7 blood-group and 10 biochemical genetic loci was examined in 3 South African horse breeds, the Nooitgedacht, Boerperd and Basuto Pony. Observed heterozygosity for these breeds was intermediate for domestic horses, with the highest heterozygosity in the Boerperd and the lowest in the Basuto Pony. The 3 breeds show greater genetic similarity to each other than to other domestic horse breeds. Compared to other breeds, the South African breeds show greater genetic similarity to breeds such as the Thoroughbred, Holstein, Trakehner and Hanovarian and also to North American breeds such as the Saddlebred, Standardbred and Morgan Horse.
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Plant breeding and genetics newsletter. No. 11
International Nuclear Information System (INIS)
2003-07-01
Implementation of a new CRP on Physical mapping technologies for the identification and characterization of mutated genes contributing to crop quality, organization of mutant germplasm database and repository, implementation of new TC projects and activation of work on molecular characterization of Musa putative germplasm as well as sequencing of BAC clones were the major activities of our sub-Programme on Plant Breeding and Genetics during the last six months. A lot of work has been concentrated on organizing a mutant germplasm repository. The first collections of rice and linseed mutants have already arrived and their descriptions have been introduced into the mutated germplasm database. We found this activity especially important to stimulate exchange of crop germplasm among plant breeders. Similarly there is an urgent need to collect mutants of various crops as necessary material for functional genomics and germplasm enhancement. Nevertheless, many crop research institutes are initiating large-scale mutation programmes with the use of their own plant material. To help them in selecting the mutagen, doses and mutation treatment procedure, we published the third issue of Mutation Breeding Newsletter Index of No. 21-44. The Index is also available through our website http://www.iaea.org/programmes/nafa/d2/index.html. The numerous requests for issues of the Mutation Breeding Newsletter already received from various countries indicate the value of this 80-page index for plant breeders and research institutes. We were invited to present the activities, achievements and trends of our sub-Programme at two very important, international meetings: The International Conference on the Status of Plant and Animal Genome Research, known as the Plant and Animal Genome (PAG XI), and The International Congress on 'In the Wake of the Double Helix - From the Green Revolution to the Gene Revolution'. At this last meeting, an initiative was taken to organize the Crop Root Research
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Plant breeding and genetics newsletter. No. 10
International Nuclear Information System (INIS)
2003-01-01
The most important event related to the activity of the Plant Breeding and Genetics sub-programme in the past six months was the 2nd FAO/IAEA Interregional Training Course on 'Mutant Germplasm Characterization using Molecular Markers' which was held at Seibersdorf, 4-29 November 2002. In addition to basic molecular and marker techniques, which were also a subject of the first training course last year, fluorescence in situ hybridisation methods were included in the teaching and demonstration programme. As we informed you in the last edition of this Newsletter, a laboratory manual was published with detailed protocols on molecular markers techniques entitled 'Mutant germplasm characterization using molecular markers. A Manual'. (IAEA Training Course Series No. 19). (available for free distribution under conditions provided on page 11 of this Newsletter). We have also finished editing a book on 'Doubled haploid production in crop plants. A Manual.' This book was prepared in close collaboration with EU COST 851 activities. Ken Kasha (Canada), Brian Forster (UK) and lwona Szarejko (Poland) helped to edit more than 40 protocols for doubled haploid production in at least 23 crop species. The preparation of this manual reflects our our interest in the development and application of this technology for crop improvement. Two CRPs and numerous Technical Co-operation projects greatly contributed to the development of doubled haploid methods and also to implementation of this technology in crop improvement programmes of many countries. Numerous other important activities have been undertaken by the Plant Breeding and Genetics sub-programme during the last 6 months. A consultants meeting on 'Low cost technology in plant tissue culture' was held in Vienna and its results will be summarized in the form of an IAEA-TECDOC which is now in the final stage of preparation. In addition to the implementation of five Co-ordinated Research Projects, nine workshops and national or regional
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Semen quality of Italian local pig breeds
Directory of Open Access Journals (Sweden)
G. Gandini
2010-01-01
Full Text Available From 1996 to 1999 a conservation programme was carried out within the framework of EC contract “European gene banking project for the pig genetic resources” (Ollivier et al., 2001 in the Italian local pig breeds. The aims of the program included the primary characterization of the breeds, i.e. information on the organization in charge of the breed, breeding population numbers, breed description and qualifications, and field trials on productive and reproductive performances. In this context the “Semen Bank of Italian local pig breeds” was built. A total of 30,835 straws of four Italian local pig breeds (Cinta Senese, Casertana, Mora Romagnola and Nero Siciliano, collected from 42 sires, have been stored. In this work semen quality traits, lipid composition and freezability of the four Italian local pig breeds are reported.
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Living with strangers: direct benefits favour non-kin cooperation in a communally nesting bird.
Riehl, Christina
2011-06-07
The greater ani (Crotophaga major), a Neotropical cuckoo, exhibits an unusual breeding system in which several socially monogamous pairs lay eggs in a single nest and contribute care to the communal clutch. Cooperative nesting is costly-females compete for reproduction by ejecting each other's eggs-but the potential direct or indirect fitness benefits that might accrue to group members have not been identified. In this study, I used molecular genotyping to quantify patterns of genetic relatedness and individual reproductive success within social groups in a single colour-banded population. Microsatellite analysis of 122 individuals in 49 groups revealed that group members are not genetic relatives. Group size was strongly correlated with individual reproductive success: solitary pairs were extremely rare and never successful, and nests attended by two pairs were significantly more likely to be depredated than were nests attended by three pairs. Egg loss, a consequence of reproductive competition, was greater in large groups and disproportionately affected females that initiated laying. However, early-laying females compensated for egg losses by laying larger clutches, and female group members switched positions in the laying order across nesting attempts. The greater ani, therefore, appears to be one of the few species in which cooperative breeding among unrelated individuals is favoured by direct, shared benefits that outweigh the substantial costs of reproductive competition.
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Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania
Directory of Open Access Journals (Sweden)
Marnix de Zeeuw
2013-01-01
Full Text Available Two new species of zooplanktivorous haplochromine cichlids from Lake Victoria, Tanzania, are described and illustrated. These species closely resemble each other. Their affinities to other zooplanktivorous haplochromines from Lake Victoria are discussed. Haplochromis argens sp. n., which featured under nicknames (mainly H. “argens” in more than 50 papers, was caught both in the Mwanza Gulf and the Emin Pasha Gulf, whereas H. goldschmidti sp. n. was only found in the Emin Pasha Gulf. Of the latter species only males are available, but it seems unlikely that it represents a case of male colour polymorphism as several presumably unrelated characters differ in sympatry between the two species, suggesting that there is no gene flow. Statistical analysis revealed that the overall difference between the two species is greater than that between the populations from the two locations. Body depth of the two species in sympatry in the Emin Pasha Gulf was more similar than that of H. goldschmidti sp. n. and the allopatric population of H. argens sp. n. from the Mwanza Gulf, which may indicate an overall environmental effect. However, several measurements related to the width of snout and mouth differed more between the populations of the two species in sympatry than between the allopatric populations. In contrast to a group of zooplanktivorous species that recovered successfully after environmental changes in the lake, H. argens sp. n. is among a group that became extremely rare and probably is in danger of extinction; the conservation status of H. goldschmidti sp. n. is currently unknown.
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Social regulation of male reproductive plasticity in an African cichlid fish.
Maruska, Karen P; Fernald, Russell D
2013-12-01
Social interactions with the outcome of a position in a dominance hierarchy can have profound effects on reproductive behavior and physiology, requiring animals to integrate environmental information with their internal physiological state; but how is salient information from the animal's dynamic social environment transformed into adaptive behavioral, physiological, and molecular-level changes? The African cichlid fish, Astatotilapia burtoni, is ideally suited to understand socially controlled reproductive plasticity because activity of the male reproductive (brain-pituitary-gonad) axis is tightly linked to social status. Males form hierarchies in which a small percentage of brightly colored dominant individuals have an active reproductive axis, defend territories, and spawn with females, while the remaining males are subordinate, drably colored, do not hold a territory, and have a suppressed reproductive system with minimal opportunities for spawning. These social phenotypes are plastic and quickly reversible, meaning that individual males may switch between dominant and subordinate status multiple times within a lifetime. Here, we review the rapid and remarkable plasticity that occurs along the entire reproductive axis when males rise in social rank, a transition that has important implications for the operational sex ratio of the population. When males rise in rank, transformations occur in the brain, pituitary, circulation, and testes over short time-scales (minutes to days). Changes are evident in overt behavior, as well as modifications at the physiological, cellular, and molecular levels that regulate reproductive capacity. Widespread changes triggered by a switch in rank highlight the significance of external social information in shaping internal physiology and reproductive competence.
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Social penalty promotes cooperation in a cooperative society.
Ito, Hiromu; Yoshimura, Jin
2015-08-04
Why cooperation is well developed in human society is an unsolved question in biological and human sciences. Vast studies in game theory have revealed that in non-cooperative games selfish behavior generally dominates over cooperation and cooperation can be evolved only under very limited conditions. These studies ask the origin of cooperation; whether cooperation can evolve in a group of selfish individuals. In this paper, instead of asking the origin of cooperation, we consider the enhancement of cooperation in a small already cooperative society. We ask whether cooperative behavior is further promoted in a small cooperative society in which social penalty is devised. We analyze hawk-dove game and prisoner's dilemma introducing social penalty. We then expand it for non-cooperative games in general. The results indicate that cooperation is universally favored if penalty is further imposed. We discuss the current result in terms of the moral, laws, rules and regulations in a society, e.g., criminology and traffic violation.
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Evolution, plant breeding and biodiversity
Directory of Open Access Journals (Sweden)
Salvatore Ceccarelli
2011-11-01
Full Text Available This paper deals with changes in biodiversity during the course of evolution, plant domestication and plant breeding. It shows than man has had a strong influence on the progressive decrease of biodiversity, unconscious at first and deliberate in modern times. The decrease in biodiversity in the agricultures of the North causes a severe threat to food security and is in contrasts with the conservation of biodiversity which is part of the culture of several populations in the South. The concluding section of the paper shows that man could have guided evolution in a different way and shows an example of participatory plant breeding, a type of breeding which is done in collaboration with farmers and is based on selection for specific adaptation. Even though participatory plant breeding has been practiced for only about 20 years and by relatively few groups, the effects on both biodiversity and crop production are impressive. Eventually the paper shows how participatory plant breeding can be developed into ‘evolutionary plant breeding’ to cope in a dynamic way with climate changes.
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Lammerts Van Bueren, E.
2010-01-01
Organic production and also the attention for plant breeding for organic agriculture is still increasing in Europe. The question often raised is how much does plant breeding for the organic sector differ from modern plant breeding and does a ban on GMO also include refraining from molecular marker
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Mutation breeding in malting barley
Energy Technology Data Exchange (ETDEWEB)
Hiraki, Makoto; Sanada, Matsuyoshi
1984-03-01
The released varieties of malting barley through mutation breeding is more than ten in number, including foreign varieties. In Japan four varieties has been released so far. We started mutation breeding in 1956 together with cross breeding that we employed before. Until now, Gamma 4, Amagi Nijo 1 and Fuji Nijo 2 have been produced from the direct use of induced mutations and Nirasaki Nijo 8 from the indirect use of them. Mutation breeding has been used mainly in the partial improvement of agronomic characteristics since the selection for malting quality was very complicated. As the variety bred by induced mutation is usually equivalent to the original variety in malting quality, both this new variety and the original one could be cultivated in the same area without any problem on later malt production. Particularly when one farmer cultivates barley in an extensive acreage, he can harvest at the best time according to the different maturing time of each variety. From these points of view, mutation breeding is an efficient tool in malting barley breeding. Mutagens we have used so far are X-rays, ..gamma..-rays, neutron and chemicals such as dES. From our experience in selection, the low dose of radiation and chemical mutagens are more effective in selection of point mutation than the high dose of radiation which tends to produce many abnormal but few practical mutants. (author).
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Bigi, D; Marelli, S P; Randi, E; Polli, M
2015-12-01
Very little research into genetic diversity of Italian native dog breeds has been carried out so far. In this study we aimed to estimate and compare the genetic diversity of four native Italian shepherd dog breeds: the Maremma, Bergamasco, Lupino del Gigante and Oropa shepherds. Therefore, some cosmopolitan dog breeds, which have been widely raised in Italy for a long time past, have also been considered to check possible influence of these dog populations on the Italian autochthonous breeds considered here. A total of 212 individuals, belonging to 10 different dog breeds, were sampled and genotyped using 18 autosomal microsatellite loci. We analyzed the genetic diversity of these breeds, within breed diversity, breed relationship and population structure. The 10 breeds considered in this study were clearly genetically differentiated from each other, regardless of current population sizes and the onset of separate breeding history. The level of genetic diversity explained 20% of the total genetic variation. The level of H E found here is in agreement with that found by other studies. The native Italian breeds showed generally higher genetic diversity compared with the long established, well-defined cosmopolitan dog breeds. As the Border Collie seems closer to the Italian breeds than the other cosmopolitan shepherd dogs considered here, a possible utilization of this breed to improve working performance in Italian traditional working shepherd dogs cannot be ignored. The data and information found here can be utilized in the organization of conservation programs planned to reduce inbreeding and to minimize loss of genetic variability.
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Ford, Antonia G P; Rüber, Lukas; Newton, Jason; Dasmahapatra, Kanchon K; Balarin, John D; Bruun, Kristoffer; Day, Julia J
2016-12-01
Ecomorphological differentiation is a key feature of adaptive radiations, with a general trend for specialization and niche expansion following divergence. Ecological opportunity afforded by invasion of a new habitat is thought to act as an ecological release, facilitating divergence, and speciation. Here, we investigate trophic adaptive morphology and ecology of an endemic clade of oreochromine cichlid fishes (Alcolapia) that radiated along a herbivorous trophic axis following colonization of an isolated lacustrine environment, and demonstrate phenotype-environment correlation. Ecological and morphological divergence of the Alcolapia species flock are examined in a phylogenomic context, to infer ecological niche occupation within the radiation. Species divergence is observed in both ecology and morphology, supporting the importance of ecological speciation within the radiation. Comparison with an outgroup taxon reveals large-scale ecomorphological divergence but shallow genomic differentiation within the Alcolapia adaptive radiation. Ancestral morphological reconstruction suggests lake colonization by a generalist oreochromine phenotype that diverged in Lake Natron to varied herbivorous morphologies akin to specialist herbivores in Lakes Tanganyika and Malawi. © 2016 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.
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Native Pig and Chicken Breed Database: NPCDB
Directory of Open Access Journals (Sweden)
Hyeon-Soo Jeong
2014-10-01
Full Text Available Indigenous (native breeds of livestock have higher disease resistance and adaptation to the environment due to high genetic diversity. Even though their extinction rate is accelerated due to the increase of commercial breeds, natural disaster, and civil war, there is a lack of well-established databases for the native breeds. Thus, we constructed the native pig and chicken breed database (NPCDB which integrates available information on the breeds from around the world. It is a nonprofit public database aimed to provide information on the genetic resources of indigenous pig and chicken breeds for their conservation. The NPCDB (http://npcdb.snu.ac.kr/ provides the phenotypic information and population size of each breed as well as its specific habitat. In addition, it provides information on the distribution of genetic resources across the country. The database will contribute to understanding of the breed’s characteristics such as disease resistance and adaptation to environmental changes as well as the conservation of indigenous genetic resources.
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Young, Kyle A.; Snoeks, Jos; Seehausen, Ole
2009-01-01
Background Deterministic evolution, phylogenetic contingency and evolutionary chance each can influence patterns of morphological diversification during adaptive radiation. In comparative studies of replicate radiations, convergence in a common morphospace implicates determinism, whereas non-convergence suggests the importance of contingency or chance. Methodology/Principal Findings The endemic cichlid fish assemblages of the three African great lakes have evolved similar sets of ecomorphs but show evidence of non-convergence when compared in a common morphospace, suggesting the importance of contingency and/or chance. We then analyzed the morphological diversity of each assemblage independently and compared their axes of diversification in the unconstrained global morphospace. We find that despite differences in phylogenetic composition, invasion history, and ecological setting, the three assemblages are diversifying along parallel axes through morphospace and have nearly identical variance-covariance structures among morphological elements. Conclusions/Significance By demonstrating that replicate adaptive radiations are diverging along parallel axes, we have shown that non-convergence in the common morphospace is associated with convergence in the global morphospace. Applying these complimentary analyses to future comparative studies will improve our understanding of the relationship between morphological convergence and non-convergence, and the roles of contingency, chance and determinism in driving morphological diversification. PMID:19270732
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Bowles, Dianna; Carson, Amanda; Isaac, Peter
2014-01-01
There is considerable interest in locally adapted breeds of livestock as reservoirs of genetic diversity that may provide important fitness traits for future use in agriculture. In marginal areas, these animals contribute to food security and extract value from land unsuitable for other systems of farming. In England, close to 50% of the national sheep flock is farmed on grassland designated as disadvantaged areas for agricultural production. Many of these areas are in the uplands, where some native breeds of sheep continue to be commercially farmed only in highly localised geographical regions to which they are adapted. This study focuses on three of these breeds, selected for their adaptation to near identical environments and their geographical concentration in regions close to one another. Our objective has been to use retrotyping, microsatellites and single nucleotide polymorphisms to explore the origins of the breeds and whether, despite their similar adaptations and proximity, they are genetically distinctive. We find the three breeds each have a surprisingly different pattern of retrovirus insertions into their genomes compared with one another and with other UK breeds. Uniquely, there is a high incidence of the R0 retrotype in the Herdwick population, characteristic of a primitive genome found previously in very few breeds worldwide and none in the UK mainland. The Herdwick and Rough Fells carry two rare retroviral insertion events, common only in Texels, suggesting sheep populations in the northern uplands have a historical association with the original pin-tail sheep of Texel Island. Microsatellite data and analyses of SNPs associated with RXFP2 (horn traits) and PRLR (reproductive performance traits) also distinguished the three breeds. Significantly, an SNP linked to TMEM154, a locus controlling susceptibility to infection by Maedi-Visna, indicated that all three native hill breeds have a lower than average risk of infection to the lentivirus.
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Directory of Open Access Journals (Sweden)
Dianna Bowles
Full Text Available There is considerable interest in locally adapted breeds of livestock as reservoirs of genetic diversity that may provide important fitness traits for future use in agriculture. In marginal areas, these animals contribute to food security and extract value from land unsuitable for other systems of farming. In England, close to 50% of the national sheep flock is farmed on grassland designated as disadvantaged areas for agricultural production. Many of these areas are in the uplands, where some native breeds of sheep continue to be commercially farmed only in highly localised geographical regions to which they are adapted. This study focuses on three of these breeds, selected for their adaptation to near identical environments and their geographical concentration in regions close to one another. Our objective has been to use retrotyping, microsatellites and single nucleotide polymorphisms to explore the origins of the breeds and whether, despite their similar adaptations and proximity, they are genetically distinctive. We find the three breeds each have a surprisingly different pattern of retrovirus insertions into their genomes compared with one another and with other UK breeds. Uniquely, there is a high incidence of the R0 retrotype in the Herdwick population, characteristic of a primitive genome found previously in very few breeds worldwide and none in the UK mainland. The Herdwick and Rough Fells carry two rare retroviral insertion events, common only in Texels, suggesting sheep populations in the northern uplands have a historical association with the original pin-tail sheep of Texel Island. Microsatellite data and analyses of SNPs associated with RXFP2 (horn traits and PRLR (reproductive performance traits also distinguished the three breeds. Significantly, an SNP linked to TMEM154, a locus controlling susceptibility to infection by Maedi-Visna, indicated that all three native hill breeds have a lower than average risk of infection to the
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Pospahala, Richard S.; Anderson, David R.; Henny, Charles J.
1974-01-01
This report, the second in a series on a comprehensive analysis of mallard population data, provides information on mallard breeding habitat, the size and distribution of breeding populations, and indices to production. The information in this report is primarily the result of large-scale aerial surveys conducted during May and July, 1955-73. The history of the conflict in resource utilization between agriculturalists and wildlife conservation interests in the primary waterfowl breeding grounds is reviewed. The numbers of ponds present during the breeding season and the midsummer period and the effects of precipitation and temperature on the number of ponds present are analyzed in detail. No significant cycles in precipitation were detected and it appears that precipitation is primarily influenced by substantial seasonal and random components. Annual estimates (1955-73) of the number of mallards in surveyed and unsurveyed breeding areas provided estimates of the size and geographic distribution of breeding mallards in North America. The estimated size of the mallard breeding population in North America has ranged from a high of 14.4 million in 1958 to a low of 7.1 million in 1965. Generally, the mallard breeding population began to decline after the 1958 peak until 1962, and remained below 10 million birds until 1970. The decline and subsequent low level of the mallard population between 1959 and 1969 .generally coincided with a period of poor habitat conditions on the major breeding grounds. The density of mallards was highest in the Prairie-Parkland Area with an average of nearly 19.2 birds per square mile. The proportion of the continental mallard breeding population in the Prairie-Parkland Area ranged from 30% in 1962 to a high of 600/0 in 1956. The geographic distribution of breeding mallards throughout North America was significantly related to the number of May ponds in the Prairie-Parkland Area. Estimates of midsummer habitat conditions and indices to
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Directory of Open Access Journals (Sweden)
Jennifer L Mortensen
Full Text Available Social behaviors can significantly affect population viability, and some behaviors might reduce extinction risk. We used population viability analysis to evaluate effects of past and proposed habitat loss on the White-breasted Thrasher (Ramphocinclus brachyurus, a cooperatively breeding songbird with a global population size of <2000 individuals. We used an individual-based approach to build the first demographic population projection model for this endangered species, parameterizing the model with data from eight years of field study before and after habitat loss within the stronghold of the species' distribution. The recent habitat loss resulted in an approximately 18% predicted decline in population size; this estimate was mirrored by a separate assessment using occupancy data. When mortality rates remained close to the pre-habitat loss estimate, quasi-extinction probability was low under extant habitat area, but increased with habitat loss expected after current plans for resort construction are completed. Post-habitat loss mortality rate estimates were too high for projected populations to persist. Vital rate sensitivity analyses indicated that population growth rate and population persistence were most sensitive to juvenile mortality. However, observed values for adult mortality were closest to the threshold value above which populations would crash. Adult mortality, already relatively low, may have the least capacity to change compared to other vital rates, whereas juvenile mortality may have the most capacity for improvement. Results suggest that improving mortality estimates and determining the cause(s of juvenile mortality should be research priorities. Despite predictions that aspects of cooperative systems may result in variation in reproduction or juvenile mortality being the most sensitive vital rates, adult mortality was the most sensitive in half of the demographic models of other avian cooperative breeders. Interestingly, vital
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Mutation breeding newsletter. No. 45
International Nuclear Information System (INIS)
2001-07-01
This issue of the Mutation Breeding newsletter contains 39 articles dealing with radiation induced mutations and chemical mutagenesis techniques in plant breeding programs with the aims of improving crop productivity and disease resistance as well as exploring genetic variabilities
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Structuring an Efficient Organic Wheat Breeding Program
Directory of Open Access Journals (Sweden)
P. Stephen Baenziger
2011-08-01
Full Text Available Our long-term goal is to develop wheat cultivars that will improve the profitability and competitiveness of organic producers in Nebraska and the Northern Great Plains. Our approach is to select in early generations for highly heritable traits that are needed for both organic and conventional production (another breeding goal, followed by a targeted organic breeding effort with testing at two organic locations (each in a different ecological region beginning with the F6 generation. Yield analyses from replicated trials at two organic breeding sites and 7 conventional breeding sites from F6 through F12 nurseries revealed, using analyses of variance, biplots, and comparisons of selected lines that it is inappropriate to use data from conventional testing for making germplasm selections for organic production. Selecting and testing lines under organic production practices in different ecological regions was also needed and cultivar selections for organic production were different than those for conventional production. Modifications to this breeding protocol may include growing early generation bulks in an organic cropping system. In the future, our selection efforts should also focus on using state-of-the-art, non-transgenic breeding technologies (genomic selection, marker-assisted breeding, and high throughput phenotyping to synergistically improve organic and conventional wheat breeding.
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Plant breeding and genetics newsletter. No. 2
International Nuclear Information System (INIS)
1998-12-01
This is the second issue of the Plant Breeding and Genetics Newsletter. The Newsletter will inform you about current activities of the FAO/IAEA sub-programme on plant breeding and genetics which is implemented by the Plant Breeding and Genetics Section of the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture (Vienna) in close collaboration with the Plant Breeding Unit of the FAO/IAEA Agriculture and Biotechnology Laboratory (Seibersdorf)
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Plant breeding and genetics newsletter. No. 1
International Nuclear Information System (INIS)
1998-05-01
This is the first issue of the Plant Breeding and Genetics Newsletter. The Newsletter will inform you about current activities of the FAO/IAEA sub-programme on plant breeding and genetics which is implemented by the Plant Breeding and Genetics Section of the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture (Vienna) in close collaboration with the Plant Breeding Unit of the FAO/IAEA Agriculture and Biotechnology Laboratory (Seibersdorf)
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Mutation breeding in mangosteen
International Nuclear Information System (INIS)
Mohd Khalid Mohd Zain
2002-01-01
Mangosteen the queen of the tropical fruits is apomitic and only a cultivar is reported and it reproduces asexually. Conventional breeding is not possible and the other methods to create variabilities are through genetic engineering and mutation breeding. The former technique is still in the infantry stage in mangosteen research while the latter has been an established tool in breeding to improve cultivars. In this mutation breeding seeds of mangosteen were irradiated using gamma rays and the LD 50 for mangosteen was determined and noted to be very low at 10 Gy. After sowing in the seedbed, the seedlings were transplanted in polybags and observed in the nursery bed for about one year before planted in the field under old oil palm trees in Station MARDI, Kluang. After evaluation and screening, about 120 mutant mangosteen plants were selected and planted in Kluang. The plants were observed and some growth data taken. There were some mutant plants that have good growth vigour and more vigorous that the control plants. The trial are now in the fourth year and the plants are still in the juvenile stage. (Author)
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Kingston-Smith, A H; Marshall, A H; Moorby, J M
2013-03-01
Animal production is a fundamental component of the food supply chain, and with an increasing global population production levels are set to increase. Ruminant animals in particular are valuable in their ability to convert a fibre-rich forage diet into a high-quality protein product for human consumption, although this benefit is offset by inefficiencies in rumen fermentation that contribute to emission of significant quantities of methane and nitrogenous waste. Through co-operation between plant and animal sciences, we can identify how the nutritional requirements of ruminants can be satisfied by high-quality forages for the future. Selective forage plant breeding has supported crop improvement for nearly a century. Early plant breeding programmes were successful in terms of yield gains (4% to 5% per decade), with quality traits becoming increasingly important breeding targets (e.g. enhanced disease resistance and digestibility). Recently, demands for more sustainable production systems have required high yielding, high-quality forages that enable efficient animal production with minimal environmental impact. Achieving this involves considering the entire farm system and identifying opportunities for maximising nutrient use efficiency in both forage and animal components. Forage crops of the future must be able to utilise limited resources (water and nutrients) to maximise production on a limited land area and this may require us to consider alternative plant species to those currently in use. Furthermore, new breeding targets will be identified as the interactions between plants and the animals that consume them become better understood. This will ensure that available resources are targeted at delivering maximum benefits to the animal through enhanced transformation efficiency.
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Directory of Open Access Journals (Sweden)
Iveta Bihuncová
2015-01-01
Full Text Available The objective of the present study was to analyse the numbers and division of horses of undefined breed. At the present time this group is the most numerous in the entire population of horses. Horses of undefined breed do not come under any breeder union which would provide reports about these horses; these horses are only registered and breeders are informed only about their numbers. Our study is the first to deal with the problem of increasing numbers of horses of undefined breed. The database contained 22 211 horses not entered registered in any of the stud books. In the database we filed approved horses born between 1972 and 1 September 2012 and horses registered from 1987. The data were processed in the Excel programme and results were evaluated in graphs. The most frequent horse in this group was the warm-blood type (n = 9 303, pony type (n = 6 285, cold-blooded type (n = 2 663 and unlisted horses (n = 2 278. Since 2001 the number of registered horses of undefined breed has increased. The most numerous dams of horses of undefined breed is the Czech warm-blood with 1 912 offspring; dams of the English Thoroughbred with 552 offspring and mares of the utility Huzule horse with 492 offspring. In the group of registered horses of undefined breed the Czech warm-blood appears in the pedigree of 507 colts and the American Paint Horse in the pedigree of sires of 506 colts. Why the numbers of horses of undefined breed are increasing is the boom of leisure horsemanship and unqualified horse breeding.
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Directory of Open Access Journals (Sweden)
Ping Zhang
2009-01-01
Full Text Available This paper proposes a user cooperation stimulating strategy among rational users. The strategy is based on cooperative game theory and enacted in the context of cooperative relay networks. Using the pricing-based mechanism, the system is modeled initially with two nodes and a Base Station (BS. Within this framework, each node is treated as a rational decision maker. To this end, each node can decide whether to cooperate and how to cooperate. Cooperative game theory assists in providing an optimal system utility and provides fairness among users. Under different cooperative forwarding modes, certain questions are carefully investigated, including “what is each node's best reaction to maximize its utility?” and “what is the optimal reimbursement to encourage cooperation?” Simulation results show that the nodes benefit from the proposed cooperation stimulating strategy in terms of utility and thus justify the fairness between each user.
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Directory of Open Access Journals (Sweden)
Jiang Fan
2009-01-01
Full Text Available This paper proposes a user cooperation stimulating strategy among rational users. The strategy is based on cooperative game theory and enacted in the context of cooperative relay networks. Using the pricing-based mechanism, the system is modeled initially with two nodes and a Base Station (BS. Within this framework, each node is treated as a rational decision maker. To this end, each node can decide whether to cooperate and how to cooperate. Cooperative game theory assists in providing an optimal system utility and provides fairness among users. Under different cooperative forwarding modes, certain questions are carefully investigated, including "what is each node's best reaction to maximize its utility?" and "what is the optimal reimbursement to encourage cooperation?" Simulation results show that the nodes benefit from the proposed cooperation stimulating strategy in terms of utility and thus justify the fairness between each user.
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Bee Queen Breeding Methods - Review
Directory of Open Access Journals (Sweden)
Silvia Patruica
2016-05-01
Full Text Available The biological potential of a bee family is mainly generated by the biological value of the queen. Whether we grow queens widely or just for our own apiaries, we must consider the acquisition of high-quality biological material, and also the creation of optimal feeding and caring conditions, in order to obtain high genetic value queens. Queen breeding technology starts with the setting of hoeing families, nurse families, drone-breeding families – necessary for the pairing of young queens, and also of the families which will provide the bees used to populate the nuclei where the next queens will hatch. The complex of requirements for the breeding of good, high-production queens is sometimes hard to met, under the application of artificial methods. The selection of breeding method must rely on all these requirements and on the beekeeper’s level of training.
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Genetic improvement of Eucalyptus grandis using breeding seedling ...
African Journals Online (AJOL)
Eucalyptus grandis is commercially important in Zimbabwe and a breeding program has been in progress since 1962. A classical breeding strategy was used initially but, in 1981, the Multiple Population Breeding Strategy (MPBS) was implemented and the concept of the Breeding Seedling Orchard (BSO) became central to ...
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Analysis of Plant Breeding on Hadoop and Spark
Directory of Open Access Journals (Sweden)
Shuangxi Chen
2016-01-01
Full Text Available Analysis of crop breeding technology is one of the important means of computer-assisted breeding techniques which have huge data, high dimensions, and a lot of unstructured data. We propose a crop breeding data analysis platform on Spark. The platform consists of Hadoop distributed file system (HDFS and cluster based on memory iterative components. With this cluster, we achieve crop breeding large data analysis tasks in parallel through API provided by Spark. By experiments and tests of Indica and Japonica rice traits, plant breeding analysis platform can significantly improve the breeding of big data analysis speed, reducing the workload of concurrent programming.
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Wang, Yu; Bennewitz, Jörn; Wellmann, Robin
2017-05-12
Optimum contribution selection (OCS) is effective for increasing genetic gain, controlling the rate of inbreeding and enables maintenance of genetic diversity. However, this diversity may be caused by high migrant contributions (MC) in the population due to introgression of genetic material from other breeds, which can threaten the conservation of small local populations. Therefore, breeding objectives should not only focus on increasing genetic gains but also on maintaining genetic originality and diversity of native alleles. This study aimed at investigating whether OCS was improved by including MC and modified kinships that account for breed origin of alleles. Three objective functions were considered for minimizing kinship, minimizing MC and maximizing genetic gain in the offspring generation, and we investigated their effects on German Angler and Vorderwald cattle. In most scenarios, the results were similar for Angler and Vorderwald cattle. A significant positive correlation between MC and estimated breeding values of the selection candidates was observed for both breeds, thus traditional OCS would increase MC. Optimization was performed under the condition that the rate of inbreeding did not exceed 1% and at least 30% of the maximum progress was achieved for all other criteria. Although traditional OCS provided the highest breeding values under restriction of classical kinship, the magnitude of MC in the progeny generation was not controlled. When MC were constrained or minimized, the kinship at native alleles increased compared to the reference scenario. Thus, in addition to constraining MC, constraining kinship at native alleles is required to ensure that native genetic diversity is maintained. When kinship at native alleles was constrained, the classical kinship was automatically lowered in most cases and more sires were selected. However, the average breeding value in the next generation was also lower than that obtained with traditional OCS. For local
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Fagundes, Ana Isabel; Ramos, Jaime A; Ramos, Urtelinda; Medeiros, Renata; Paiva, Vitor H
2016-10-01
The breeding success of burrow-nesting seabirds may be influenced by both nest site characteristics and oceanographic conditions influencing food availability at sea. In this study we describe the breeding biology of the winter-breeding Macaronesian shearwater (Puffinus lherminieri baroli), including nest site characteristics and interspecific competition. We also evaluate the possible effects of changing oceanographic conditions on breeding phenology and breeding success. The study was carried out over two breeding seasons on two islands in the North Atlantic Ocean, Cima Islet and Selvagem Grande. Oceanographic characteristics differed between years. On a regional scale, the North Atlantic Oscillation (NAO) index was low and negative in 2011, and on a local scale, birds used areas with significantly lower values of chlorophyll a concentration and significantly higher values of sea surface temperature anomalies. Hatching success was higher in 2012 than in 2011. At both colonies, egg cracking was the main cause of hatching failure, but in 2011 several eggs on Selvagem Grande were deserted. In 2012 birds laid earlier and chicks had longer wings and were heavier. At both colonies, nests that were deeper, were sheltered from prevailing winds and had small chambers and a soil substrate had a higher probability of being used successfully by the birds. Nests occupied solely by Macaronesian shearwaters were much deeper and had less volume than nests shared with other species. Our study suggests that the breeding success of Macaronesian shearwaters is strongly related to nest site characteristics and that at-sea environmental conditions exert a strong influence on reproductive parameters, with birds breeding in a poor year (evaluated in terms of lower marine productivity) laying much later and their chicks growing at a slower rate than in a good year. The influence of nest site characteristics and environmental conditions may be very important for understanding the breeding
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RosBREED: Enabling marker-assisted breeding in Rosaceae
Iezzoni, A.F.; Weebadde, C.; Luby, J.; Yue, C.; Weg, van de W.E.; Fazio, G.; Main, D.; Peace, C.P.; Bassil, N.V.; McFerson, J.
2010-01-01
Genomics research has not yet been translated into routine practical application in breeding Rosaceae fruit crops (peach, apple, strawberry, cherry, apricot, pear, raspberry, etc.). Through dedicated efforts of many researchers worldwide, a wealth of genomics resources has accumulated, including EST
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Directory of Open Access Journals (Sweden)
Hoffmann Erik
2012-03-01
Full Text Available Abstract Background Androgens induce male characters by activating androgen receptors (AR. Previous quantitative studies on AR in fishes have been limited to few tissues and/or a single season/reproductive state. The aim of this investigation was to study the possible role of AR-beta expression levels in the control of male traits in the three-spined stickleback. To that end, AR-beta expression levels in major tissues in breeding and post-breeding male and female sticklebacks were examined. Methods AR-beta mRNA levels were quantified in ten tissues; eye, liver, axial muscle, heart, brain, intestine, ovary, testis, kidney and pectoral muscle in six breeding and post-breeding males and females using reverse transcription quantitative PCR. Results Breeding in contrast to post-breeding males built nests and showed secondary sexual characters (e.g. kidney hypertrophy and elevated androgen levels. Post-breeding females had lower ovarian weights and testosterone levels than breeding females. AR-beta was expressed in all studied tissues in both sexes and reproductive states with the highest expression in the gonads and in the kidneys. The kidney is an androgen target organ in sticklebacks, from which breeding males produce the protein spiggin, which is used in nest-building. There was also high AR-beta expression in the intestine, an organ that appears to take over hyperosmo-regulation in fresh water when the kidney hypertrophies in mature males and largely loses this function. The only tissue that showed effects of sex or reproductive state on AR-beta mRNA levels was the kidneys, where post-breeding males displayed higher AR-beta mRNA levels than breeding males. Conclusion The results indicate that changes in AR-beta mRNA levels play no or little role in changes in androgen dependent traits in the male stickleback.
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Onzima, R.B.; Mukiibi, Robert; Ampaire, A.; Benda-Beckmann, von K.; Kanis, E.
2017-01-01
Gastrointestinal nematodes (GINs), Haemonchus contortus, are a major health problem in goat production. Resistance to H. contortus, the most prevalent GIN in Uganda, was studied among three indigenous goat breeds to assess their differences. Twelve male goats of each breed approximately 7 months old
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Onzima, R.B.; Gizaw, S.; Kugonza, D.R.; Arendonk, van J.A.M.; Kanis, E.
2018-01-01
The success of breeding programs in improving indigenous livestock breeds in Uganda has hitherto been limited due to lack of involvement of the key stakeholders. Thus, participatory approaches are being promoted for designing community based improvement programs. The aim of this study was to
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Onzima, R.B.; Gizaw, S.; Kugonza, D.R.; Arendonk, van J.A.M.; Kanis, E.
2017-01-01
The success of breeding programs in improving indigenous livestock breeds in Uganda has hitherto been limited due to lack of involvement of the key stakeholders. Thus, participatory approaches are being promoted for designing community based improvement programs. The aim of this study was to
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Assigning breed origin to alleles in crossbred animals.
Vandenplas, Jérémie; Calus, Mario P L; Sevillano, Claudia A; Windig, Jack J; Bastiaansen, John W M
2016-08-22
For some species, animal production systems are based on the use of crossbreeding to take advantage of the increased performance of crossbred compared to purebred animals. Effects of single nucleotide polymorphisms (SNPs) may differ between purebred and crossbred animals for several reasons: (1) differences in linkage disequilibrium between SNP alleles and a quantitative trait locus; (2) differences in genetic backgrounds (e.g., dominance and epistatic interactions); and (3) differences in environmental conditions, which result in genotype-by-environment interactions. Thus, SNP effects may be breed-specific, which has led to the development of genomic evaluations for crossbred performance that take such effects into account. However, to estimate breed-specific effects, it is necessary to know breed origin of alleles in crossbred animals. Therefore, our aim was to develop an approach for assigning breed origin to alleles of crossbred animals (termed BOA) without information on pedigree and to study its accuracy by considering various factors, including distance between breeds. The BOA approach consists of: (1) phasing genotypes of purebred and crossbred animals; (2) assigning breed origin to phased haplotypes; and (3) assigning breed origin to alleles of crossbred animals based on a library of assigned haplotypes, the breed composition of crossbred animals, and their SNP genotypes. The accuracy of allele assignments was determined for simulated datasets that include crosses between closely-related, distantly-related and unrelated breeds. Across these scenarios, the percentage of alleles of a crossbred animal that were correctly assigned to their breed origin was greater than 90 %, and increased with increasing distance between breeds, while the percentage of incorrectly assigned alleles was always less than 2 %. For the remaining alleles, i.e. 0 to 10 % of all alleles of a crossbred animal, breed origin could not be assigned. The BOA approach accurately assigns
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Prospects for Hybrid Breeding in Bioenergy Grasses
DEFF Research Database (Denmark)
Aguirre, Andrea Arias; Studer, Bruno; Frei, Ursula
2012-01-01
, we address crucial topics to implement hybrid breeding, such as the availability and development of heterotic groups, as well as biological mechanisms for hybridization control such as self-incompatibility (SI) and male sterility (MS). Finally, we present potential hybrid breeding schemes based on SI...... of different hybrid breeding schemes to optimally exploit heterosis for biomass yield in perennial ryegrass (Lolium perenne L.) and switchgrass (Panicum virgatum), two perennial model grass species for bioenergy production. Starting with a careful evaluation of current population and synthetic breeding methods...
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Breeding strategies for north central tree improvement programs
Ronald P. Overton; Hyun Kang
1985-01-01
The rationales and concepts of long-term tree breeding are discussed and compared with those for short-term breeding. A model breeding program is reviewed which maximizes short-term genetic gain for currently important traits and provides genetic resources that can be used effectively in future short-term breeding. The resources of the north-central region are examined...
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Population structure of four Thai indigenous chicken breeds.
Mekchay, Supamit; Supakankul, Pantaporn; Assawamakin, Anunchai; Wilantho, Alisa; Chareanchim, Wanwisa; Tongsima, Sissades
2014-03-27
In recent years, Thai indigenous chickens have increasingly been bred as an alternative in Thailand poultry market. Due to their popularity, there is a clear need to improve the underlying quality and productivity of these chickens. Studying chicken genetic variation can improve the chicken meat quality as well as conserving rare chicken species. To begin with, a minimal set of molecular markers that can characterize the Thai indigenous chicken breeds is required. Using AFLP-PCR, 30 single nucleotide polymorphisms (SNPs) from Thai indigenous chickens were obtained by DNA sequencing. From these SNPs, we genotyped 465 chickens from 7 chicken breeds, comprising four Thai indigenous chicken breeds--Pradhuhangdum (PD), Luenghangkhao (LK), Dang (DA) and Chee (CH), one wild chicken--the red jungle fowls (RJF), and two commercial chicken breeds--the brown egg layer (BL) and commercial broiler (CB). The chicken genotypes reveal unique genetic structures of the four Thai indigenous chicken breeds. The average expected heterozygosities of PD=0.341, LK=0.357, DA=0.349 and CH=0.373, while the references RJF= 0.327, CB=0.324 and BL= 0.285. The F(ST) values among Thai indigenous chicken breeds vary from 0.051 to 0.096. The F(ST) values between the pairs of Thai indigenous chickens and RJF vary from 0.083 to 0.105 and the FST values between the Thai indigenous chickens and the two commercial chicken breeds vary from 0.116 to 0.221. A neighbour-joining tree of all individual chickens showed that the Thai indigenous chickens were clustered into four groups which were closely related to the wild RJF but far from the commercial breeds. Such commercial breeds were split into two closely groups. Using genetic admixture analysis, we observed that the Thai indigenous chicken breeds are likely to share common ancestors with the RJF, while both commercial chicken breeds share the same admixture pattern. These results indicated that the Thai indigenous chicken breeds may descend from the
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Owner perceived differences between mixed-breed and purebred dogs.
Turcsán, Borbála; Miklósi, Ádám; Kubinyi, Enikő
2017-01-01
Studies about the behaviours of mixed-breed dogs are rare, although mixed-breeds represent the majority of the world's dog population. We have conducted two surveys to investigate the behavioural, demographic, and dog keeping differences between purebred and mixed-breed companion dogs. Questionnaire data were collected on a large sample of dogs living in Germany (N = 7,700 purebred dogs representing more than 200 breeds, and N = 7,691 mixed-breeds). We found that according to their owners, mixed-breeds were (1) less calm, (2) less sociable toward other dogs, and (3) showed more problematic behaviour than purebreds (p dog keeping factors differed between purebred and mixed-breed dogs, and two factors showed considerable (> 10%) differences: neutering was more frequent among mixed-breeds, and they were acquired at older ages than purebreds (p dog keeping factors, we found that mixed-breeds were (1) more trainable than purebreds, (2) less calm, and (3) showed more problematic behaviour than purebreds (p dogs, mixed-breeds represent a special group with characteristic behavioural traits.
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Directory of Open Access Journals (Sweden)
David Berthier
Full Text Available Animal African Trypanosomosis particularly affects cattle and dramatically impairs livestock development in sub-Saharan Africa. African Zebu (AFZ or European taurine breeds usually die of the disease in the absence of treatment, whereas West African taurine breeds (AFT, considered trypanotolerant, are able to control the pathogenic effects of trypanosomosis. Up to now, only one AFT breed, the longhorn N'Dama (NDA, has been largely studied and is considered as the reference trypanotolerant breed. Shorthorn taurine trypanotolerance has never been properly assessed and compared to NDA and AFZ breeds.This study compared the trypanotolerant/susceptible phenotype of five West African local breeds that differ in their demographic history. Thirty-six individuals belonging to the longhorn taurine NDA breed, two shorthorn taurine Lagune (LAG and Baoulé (BAO breeds, the Zebu Fulani (ZFU and the Borgou (BOR, an admixed breed between AFT and AFZ, were infected by Trypanosoma congolense IL1180. All the cattle were genetically characterized using dense SNP markers, and parameters linked to parasitaemia, anaemia and leukocytes were analysed using synthetic variables and mixed models. We showed that LAG, followed by NDA and BAO, displayed the best control of anaemia. ZFU showed the greatest anaemia and the BOR breed had an intermediate value, as expected from its admixed origin. Large differences in leukocyte counts were also observed, with higher leukocytosis for AFT. Nevertheless, no differences in parasitaemia were found, except a tendency to take longer to display detectable parasites in ZFU.We demonstrated that LAG and BAO are as trypanotolerant as NDA. This study highlights the value of shorthorn taurine breeds, which display strong local adaptation to trypanosomosis. Thanks to further analyses based on comparisons of the genome or transcriptome of the breeds, these results open up the way for better knowledge of host-pathogen interactions and
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Relationships among and variation within rare breeds of swine.
Roberts, K S; Lamberson, W R
2015-08-01
Extinction of rare breeds of livestock threatens to reduce the total genetic variation available for selection in the face of the changing environment and new diseases. Swine breeds facing extinction typically share characteristics such as small size, slow growth rate, and high fat percentage, which limit them from contributing to commercial production. Compounding the risk of loss of variation is the lack of pedigree information for many rare breeds due to inadequate herd books, which increases the chance that producers are breeding closely related individuals. By making genetic data available, producers can make more educated breeding decisions to preserve genetic diversity in future generations, and conservation organizations can prioritize investments in breed preservation. The objective of this study was to characterize genetic variation within and among breeds of swine and prioritize heritage breeds for preservation. Genotypes from the Illumina PorcineSNP60 BeadChip (GeneSeek, Lincoln, NE) were obtained for Guinea, Ossabaw Island, Red Wattle, American Saddleback, Mulefoot, British Saddleback, Duroc, Landrace, Large White, Pietrain, and Tamworth pigs. A whole-genome analysis toolset was used to construct a genomic relationship matrix and to calculate inbreeding coefficients for the animals within each breed. Relatedness and average inbreeding coefficient differed among breeds, and pigs from rare breeds were generally more closely related and more inbred ( Guinea pigs. Tamworth, Duroc, and Mulefoot tended to not cluster with the other 7 breeds.
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Stress axis regulation during social ascension in a group-living cichlid fish.
Culbert, Brett M; Gilmour, Kathleen M; Balshine, Sigal
2018-06-19
Animals living in groups often form social hierarchies, with characteristic behaviours and physiologies associated with rank. However, when social opportunities arise and a subordinate ascends into a dominant position, quick adjustments are necessary to secure this position. Such periods of social transition are typically associated with elevated glucocorticoid production, but the precise regulation of the stress axis during these occasions is not well understood. Using the group-living cichlid, Neolamprologus pulcher, the effects of social ascension on the stress axis were assessed. Ascenders rapidly filled experimentally created vacancies, adopting a dominant behavioural phenotype within 72 h-elevating aggression, activity, and workload, while receiving high rates of affiliative behaviours from their group members. Despite assuming behavioural dominance within their groups, ascenders displayed higher cortisol levels than dominants three days post-ascension. Additionally, compared to subordinates, ascenders had increased transcript abundance of steroidogenic acute regulatory protein (star) and cytochrome p450 side-chain cleavage enzyme (p450scc) in the head kidney, indicating activation of the stress axis. Cortisol levels were lowest in ascenders that displayed low rates of aggression, potentially reflecting the reestablishment of social stability in these groups. Increased transcript abundance of both glucocorticoid receptors (gr1 and gr2) in the brain's preoptic area (POA) of ascenders compared to dominants suggested an enhanced capacity for cortisol regulation via negative feedback. Our results reveal a regulatory cascade of behavioural and physiological interactions and highlight the importance of investigating the underlying mechanisms regulating the stress axis. Copyright © 2018. Published by Elsevier Inc.
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Traoré, S A; Markemann, A; Reiber, C; Piepho, H P; Valle Zárate, A
2017-04-01
Many local livestock breeds in developing countries are being replaced by exotic breeds, leading to a loss of genetic resources. In southern Mali, for the past two decades, a trend towards increasing crossbreeding between the trypanotolerant N'Dama cattle and the trypano-susceptible Fulani Zebu cattle has been taking place. A survey with 160 farmers owning a cattle herd was carried out in southern Mali to investigate their production objectives, as well as trait and breed preferences and correlated socio-economic determinants in order to understand farmers' breeding decisions and to identify comparative advantages of three breed groups (N'Dama, Fulani Zebu and crossbreds) raised in the study area. Data were analyzed using an exploded logit model. The reasons for raising cattle, as well as trait and breed preferences reflected the multiple objectives of the farmers. Draught power and savings were the most important production objectives. Productive traits were ranked highest; farmers reported large body size as the most preferred trait, followed by fertility, draught ability and milk yield. Crossbreds were the favored breed group. Breed preferences were mainly explained by 'resistance to disease' for N'Dama cattle and 'high market price' for Fulani Zebu and crossbred cattle. Production objectives, trait and breed preferences were mainly influenced by farmer group (local farmers and settled transhumants). Local farmers put comparatively more emphasis on livestock functions linked to crop production such as draught power. They had a higher preference for traction ability as a selection trait and preferred N'Dama over Fulani Zebu cattle. Settled transhumants emphasized milk yield as a selection trait and preferred Fulani Zebu over N'Dama. The results indicate that the trend towards more crossbreeding will continue putting the N'Dama breed under high risk of genetic dilution in southern Mali. The N'Dama cattle remain a valuable breed due to their adaptive traits such as
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Prevalence of congenital heart disease in 76,301 mixed-breed dogs and 57,025 mixed-breed cats.
Schrope, Donald P
2015-09-01
Assess the prevalence of congenital heart disease (CHD) in a large population of mixed-breed dogs and cats. 76,301 mixed-breed dogs and 57,025 mixed-breed cats. Retrospective review of records and examinations based on specified diagnostic criteria. Among mixed-breed dogs, the prevalence of CHD was 0.13% (51.4% female) and of innocent murmurs was 0.10% (53.0% male). Pulmonic stenosis was the most common defect followed by patent ductus arteriosus, aortic stenosis, and ventricular septal defect. Among mixed-breed cats, prevalence of CHD was 0.14% (55.2% male) and of innocent murmurs was 0.16% (54.4% male). When the 25 cats with dynamic left or right ventricular outflow obstruction were counted with cases of innocent murmurs, the overall prevalence was 0.2%. Ventricular septal defects were the most common feline CHD followed closely by aortic stenosis and hypertrophic obstructive cardiomyopathy. There was no overall sex predilection for CHD in mixed-breed cats or dogs, and no significant difference in CHD prevalence between cats or dogs. Among dogs, subvalvular aortic stenosis and mitral valve dysplasia had a male predisposition while patent ductus arteriosus had a female predisposition. Among cats, valvular pulmonic stenosis, subvalvular and valvular aortic stenosis, and ventricular septal defects had a male predisposition while pulmonary artery stenosis had a female predisposition. The prevalence of CHD in a mixed-breed dogs and cats is lower than for prior studies, perhaps due to the lack of purebreds in the study population or actual changes in disease prevalence. Copyright © 2015 Elsevier B.V. All rights reserved.
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SPRING BARLEY BREEDING FOR MALTING QUALITY
Alžbeta Žofajová; Jozef Gubiš; Ľudovít Sleziak; Klára Križanová; Vratislav Psota
2010-01-01
The aim of this contribution is to illustrate the results of spring barley breeding for malting quality and point out an important position of variety in production of qualitative raw material for maltinq and beer industry as well as the system of evaluation the qualitative parameters of breeding materials and adaptation of barley breeding programms to the new requirements of malting and beer industry. As an example of the results obtained most recently descripti...
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To cooperate or not to cooperate
DEFF Research Database (Denmark)
Wessels, Josepha Ivanka
To Cooperate or not to Cooperate...? discusses results of a research project to study the rehabilitation of 1500-year old water tunnels, so called "qanats", in Syria. Communities all over the world are using traditional technologies to extract drinkingwater, irrigate their lands and feed...... their livestock. But these often sustainable and ancient ways to make use of groundwater are in rapid decline worldwide. A research project started in 1999 to study the rehabilitation of 1500-year old water tunnels called "qanats"in Syria. To Cooperate or not to Cooperate...? discusses results and outcomes...
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Aguirre-Ayala, Daniel; Vidal-Martínez, Víctor Manuel
2015-08-01
This study aimed to determine the susceptibility of the Mayan cichlid Cichlasoma urophthalmus to infection with the fungus Aphanomyces invadans (also known as epizootic ulcerative syndrome [EUS]). A total of 27 C. urophthalmus were exposed to the original A. Invadans 2006/86/EC strain by intramuscularly injecting the fish with 25,000 zoospores/ml or exposing the fish to a suspension of 25,000 zoospores/ml in 6-L aquaria for 30 days. To assess the infectious capacity of A. invadans, 3 golden barbs (Puntius semifasciolatus) were infected intramuscularly with 200,000 zoospores/ml. A second experiment using 100 C. urophthalmus was performed for 60 days with 50 fish in each treatment group. A polymerase chain reaction (PCR)-based diagnostic method was used; muscle and gills were the target tissues. In the first experiment, none of the exposed C. urophthalmus developed skin lesions related to A. invadans infection. However, PCR analysis revealed that infection had occurred. For the intramuscular treatment, there were significant differences between the controls and the muscle samples (Fisher's exact test; P 0.05). All golden barbs became infected, as indicated by PCR, and developed skin lesions typical of A. invadans infection. We concluded that C. urophthalmus was infected with A. invadans but was an asymptomatic carrier because skin lesions did not develop. In the second experiment, all fish were negative, suggesting that the fish had cleared the infection by the end of the experiment.
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Directory of Open Access Journals (Sweden)
Nishida Mutsumi
2007-10-01
Full Text Available Abstract Background Cichlid fishes in Lake Tanganyika exhibit remarkable diversity in their feeding habits. Among them, seven species in the genus Perissodus are known for their unique feeding habit of scale eating with specialized feeding morphology and behaviour. Although the origin of the scale-eating habit has long been questioned, its evolutionary process is still unknown. In the present study, we conducted interspecific phylogenetic analyses for all nine known species in the tribe Perissodini (seven Perissodus and two Haplotaxodon species using amplified fragment length polymorphism (AFLP analyses of the nuclear DNA. On the basis of the resultant phylogenetic frameworks, the evolution of their feeding habits was traced using data from analyses of stomach contents, habitat depths, and observations of oral jaw tooth morphology. Results AFLP analyses resolved the phylogenetic relationships of the Perissodini, strongly supporting monophyly for each species. The character reconstruction of feeding ecology based on the AFLP tree suggested that scale eating evolved from general carnivorous feeding to highly specialized scale eating. Furthermore, scale eating is suggested to have evolved in deepwater habitats in the lake. Oral jaw tooth shape was also estimated to have diverged in step with specialization for scale eating. Conclusion The present evolutionary analyses of feeding ecology and morphology based on the obtained phylogenetic tree demonstrate for the first time the evolutionary process leading from generalised to highly specialized scale eating, with diversification in feeding morphology and behaviour among species.
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Kautt, Andreas F; Machado-Schiaffino, Gonzalo; Torres-Dowdall, Julian; Meyer, Axel
2016-08-01
Understanding how speciation can occur without geographic isolation remains a central objective in evolutionary biology. Generally, some form of disruptive selection and assortative mating are necessary for sympatric speciation to occur. Disruptive selection can arise from intraspecific competition for resources. If this competition leads to the differential use of habitats and variation in relevant traits is genetically determined, then assortative mating can be an automatic consequence (i.e., habitat isolation). In this study, we caught Midas cichlid fish from the limnetic (middle of the lake) and benthic (shore) habitats of Crater Lake Asososca Managua to test whether some of the necessary conditions for sympatric speciation due to intraspecific competition and habitat isolation are given. Lake As. Managua is very small (Midas cichlids, Amphilophus tolteca. We found that fish from the limnetic habitat were more elongated than fish collected from the benthic habitat, as would be predicted from ecomorphological considerations. Stable isotope analyses confirmed that the former also exhibit a more limnetic lifestyle than the latter. Furthermore, split-brood design experiments in the laboratory suggest that phenotypic plasticity is unlikely to explain much of the observed differences in body elongation that we observed in the field. Yet, neutral markers (microsatellites) did not reveal any genetic clustering in the population. Interestingly, demographic inferences based on RAD-seq data suggest that the apparent lack of genetic differentiation at neutral markers could simply be due to a lack of time, as intraspecific competition may only have begun a few hundred generations ago.
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Effect of mate size on maternal reproductive effort in the convict cichlid Amatitlania siquia
Institute of Scientific and Technical Information of China (English)
Ashley R. ROBART
2012-01-01
The differential allocation hypothesis predicts individuals will increase their reproductive investment when mated to a high quality partner.In many species of fish with biparental care females prefer large males due to the males' greater ability to raise more offspring to independence.I examined the relationship between mate quality,parental care and number of offspring in a natural population of convict cichlids Amatitlania siquia.The frequency of frontal displays by females was positively correlated with male standard length.Additionally,as males increased in length relative to their mate,females increased the frequency of chases towards predators,while males decreased the number of displays towards brood predators.This trade-off in parental effort within a pair due to mate quality is a key prediction of differential allocation.The number of offspring was correlated with male,but not female,standard length.These results support the differential allocation hypothesis in that females offered more parental care to offspring of a larger male,while their mates decreased the amount of care they provided.Additionally,females benefited in terms of number of offspring by pairing with higher quality mates.Increased female investment may provide an incentive to ensure male care and maintain pair bonding,which could lead to greater reproductive success through increased offspring survival [Current Zoology 58 (1):66-72,2012].
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Effect of mate size on maternal reproductive effort in the convict cichlid Amatitlania siquia
Directory of Open Access Journals (Sweden)
Ashley R. ROBART
2012-02-01
Full Text Available The differential allocation hypothesis predicts individuals will increase their reproductive investment when mated to a high quality partner. In many species of fish with biparental care females prefer large males due to the males’ greater ability to raise more offspring to independence. I examined the relationship between mate quality, parental care and number of offspring in a natural population of convict cichlids Amatitlania siquia. The frequency of frontal displays by females was positively correlated with male standard length. Additionally, as males increased in length relative to their mate, females increased the frequency of chases towards predators, while males decreased the number of displays towards brood predators. This trade-off in parental effort within a pair due to mate quality is a key prediction of differential allocation. The number of offspring was correlated with male, but not female, standard length. These results support the differential allocation hypothesis in that females offered more parental care to offspring of a larger male, while their mates decreased the amount of care they provided. Additionally, females benefited in terms of number of offspring by pairing with higher quality mates. Increased female investment may provide an incentive to ensure male care and maintain pair bonding, which could lead to greater reproductive success through increased offspring survival [Current Zoology 58 (1: 66–72, 2012].
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Biology of Crassicutis cichlasomae, a parasite of cichlid fishes in Mexico and Central America.
Scholz, T; Pech-Ek, M C; Rodriguez-Canul, R
1995-03-01
Field study on the biology of Crassicutis cichlasomae Manter, 1936 (Digenea: Homalometridae) was carried out in a small swamp in a limestone factory near Mérida, Yucatán, Mexico. Aquatic snails, Littorina (Littoridinopis) angulifera, harbouring C. cichlasomae rediae, cercariae and metacercariae, served both as the first and second intermediate hosts. Feeding experiments confirmed the conspecificity of metacercariae from naturally infected snails with adults from naturally infected fish. Gravid C. cichlasomae worms were obtained from experimentally infected fish 19 days post exposure at 22-24 degrees C. Examination of fish from the swamp in Mitza and other localities in the Yucatan Peninsula showed that the cichlids Cichlasoma urophthalmus and C. meeki were definitive hosts of C. cichlasomae. There was no pronounced preference of C. cichlasomae adults for the site of their location in the intestine of the definitive host; a slightly higher proportion (41%) of worms was only found in the anterior third of the gut. The time of miracidium development varied from 18.5 to 27.5 days; different temperature (20.1-35.7 degrees C) or light/darkness regimes influenced only slightly the rate of embryonic development, with shorter development times at higher temperature (34.8-35.7 degrees C) and constant darkness and/or light. With the exception of the sporocyst, all developmental stages are described and figured.
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National Breeding System of Dairy Cattle Husbandry
Directory of Open Access Journals (Sweden)
Anneke Anggraeni
1999-05-01
Full Text Available The husbandry of domestic dairy cattle as one of the components of livestock sub-sector development is hopefully to increase numerously the capacity and the quality on its milk production, to gradually meet national milk demand and face the competitiveness at the global. The achievement of this purpose should be supported by the production of dairy breeding stock in good quality and sufficient number to increase efficiency of both quantity and quality of domestic milk production. One of important aspect that should be prepared is in determining national breeding system of dairy cattle that can function effectively as guidance and regulation for producing, distributing, and using dairy cattle as “domestic breeding stock”. As in other livestock, breeding system of dairy cattle basically constituted of three main subsystems, i.e. production , distribution and marketing, and quality establishment subsystem. The paper discusses some aspects of these three subsystems to give considerable input in preparing the national concept of dairy cattle breeding system. enterprise (Animal Production 1(2: 43-55 (1999 KeyWords: dairy cattle, breeding stock, milk production.
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National Breeding System of Dairy Cattle Husbandry
Directory of Open Access Journals (Sweden)
K Diwyanto
1999-05-01
Full Text Available The husbandry of domestic dairy cattle as one of the components of livestock sub-sector development is hopefully to increase numerously the capacity and the quality on its milk production, to gradually meet national milk demand and face the competitiveness at the global. The achievement of this purpose should be supported by the production of dairy breeding stock in good quality and sufficient number to increase efficiency of both quantity and quality of domestic milk production. One of important aspect that should be prepared is in determining national breeding system of dairy cattle that can function effectively as guidance and regulation for producing, distributing, and using dairy cattle as “domestic breeding stock”. As in other livestock, breeding system of dairy cattle basically constituted of three main subsystems, i.e. production , distribution and marketing, and quality establishment subsystem. The paper discusses some aspects of these three subsystems to give considerable input in preparing the national concept of dairy cattle breeding system. enterprise (Animal Production 1(2: 43-55 (1999 KeyWords: dairy cattle, breeding stock, milk production.
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Le, Thi Thanh Huyen; Muth, Philipp C; Markemann, André; Schöll, Kerstin; Zárate, Anne Valle
2016-02-01
Based on 12 years of research (SFB 564 "The Uplands Program"), a community-based breeding and marketing cooperative group was transferred to an ethnic farmer group. This study analyses the potential for developing a marketing channel for specialty local Ban pork as an alternative to supplying the local markets to ensure long-term sustainability of the communal local pig breeding and production system. Data on pig-keeping were investigated from 378 farmers who wanted to enroll in the cooperative group in 10 villages (near town, intermediate, and remote zones) in Son La province. The data on Ban pig marketing activities of the cooperative group were investigated for all of its 180 members. Information on the market demand for Ban pigs were collected by interviewing 57 traders in Hanoi city and Son La province. The results show a dominance of local Ban in remote areas, and a preference for crossbreds with exotics in closer-to-town areas. Before farmers joined the cooperative group, the commercialization of pigs in remote villages accounted for only 3.0 pigs/farm/year compared to 9.3 pigs/farm/year in the intermediate zone and 11.2 pigs/farm/year near town. Potential markets have been identified for each product category of the cooperative group. Pure Ban pigs with a weight of 10-15 kg were preferred most by customers in Hanoi city. The regular feedback of information on niche markets for different products has increased the awareness of farmers about the competitiveness of the local pig products, and the power of collective action in the market. Selected pure Ban pigs were increasingly sold to food stores in Hanoi with high prices. Farmers received an average of 9000 VND more compared to the local market price for each kg of live weight. The respective added value for the cooperative group amounted to 11,300 VND/kg live weight. The added value from selling specialty Ban pigs regularly to markets, encouraged farmers toward a market in local pig production and
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Is income breeding an appropriate construct for waterfowl?
Janke, Adam K.; Anteau, Michael J.; Markl, Nicholas; Stafford, Joshua D.
2015-01-01
Breeding birds use a range of nutrient accumulation and allocation strategies to meet the nutritional demands of clutch formation and incubation. On one end of the spectrum, capital breeders use stored nutrients acquired prior to clutch formation and incubation to sustain metabolism during reproduction, while on the opposite end, income breeders derive nutrients solely from exogenous sources on the breeding grounds. Blue-winged Teal (Anas discors) are an ideal candidate to test for adoption of an income strategy among migratory waterfowl because of their small body size, temperate breeding range, and timing of reproduction relative to pulses in nutrient availability within breeding habitats. We collected migrating and pre-breeding Blue-winged Teal (n = 110) during the warmest spring in over a century in the southern edge of the species’ breeding range, which produced ideal conditions to test for adoption of an income breeding strategy among migratory waterfowl. Regression analyses revealed that females accumulated protein and fat reserves early in follicle development and appeared to mobilize at least some reserves coincident with the onset of clutch formation. Accumulation and subsequent mobilization of nutrient reserves was inconsistent with adherence to an income breeding strategy and suggested breeding Blue-winged Teal used capital (albeit locally acquired) for reproduction. Our results add to existing knowledge on the ubiquity of endogenous nutrient reserve accumulation prior to and during reproduction by waterfowl, perhaps suggesting endogenous nutrient reserves are universally used for clutch formation or incubation to some degree. If indeed Blue-winged Teal and other waterfowl universally use capital for breeding, research and conservation efforts should shift from evaluating whether an income breeding strategy is used and focus on when and where necessary capital is acquired prior to clutch formation.
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CAGE BREEDING OF WARM WATER FRESHWATER FISH SPECIES
Directory of Open Access Journals (Sweden)
Roman Safner
2008-10-01
Full Text Available In the 1970s, Croatia became actively involved in the contemporary trend of breeding fish in floating cages. In addition to various species of marine fishes, breeding was attempted with trout, carp, catfish, cisco and salmon. Of the above freshwater fish species, specific standards were established only for the cage breeding of rainbow trout. Cage breeding of the remaining species remained at the level of occasional attempts, with more of an experimental than a commercial character. The regular attempts to master this technique for cage breeding of warm water freshwater fish species were aimed at achieving the known benefits of such breeding, such as simplicity of implementing technological measures, easier establishment of the breeding system, simpler manipulation, the possibility of denser colonies per unit volume with a high level of production, easier adaptations to market conditions and fewer initial structural investments. Despite the many advantages, the main reasons for the lack of greater implementation of the cage breeding technology for warm water species of freshwater fish include problems in obtaining the appropriate category and quantity of healthy fry, the specificity and applicability of physical and chemical properties of the recipients and human error. In evaluating the advantages and disadvantages, the final decision on the justification of cage breeding for individual warm water freshwater species must be based on both biological and economic factors. Based on the knowledge of cage breeding acquired to date, the rule for virtually all intensive breeding systems is that it is only recommended for those species with high market demand and a high market price. The technology that demands nutrition with highly concentrated feed and other production expenditures is costly, and is therefore not profitable with less expensive fish species. Furthermore, production must be market oriented, i.e. the appropriate market research measures
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Genetic diversity and relationships of Vietnamese and European pig breeds
Energy Technology Data Exchange (ETDEWEB)
Thuy, N T.D. [Department of Animal Breeding and Biotechnology, University of Hohenheim, Stuttgart (Germany); Institute of Biotechnology (IBT), National Center for Natural Science and Technology, Hanoi (Viet Nam); Melchinger, E; Kuss, A W; Peischl, T; Bartenschlager, H; Geldermann, H [Department of Animal Breeding and Biotechnology, University of Hohenheim, Stuttgart (Germany); Cuong, N V [Institute of Biotechnology (IBT), National Center for Natural Science and Technology, Hanoi (Viet Nam)
2005-07-01
Indigenous resources of the Asian pig population are less defined and only rarely compared with European breeds. In this study, five indigenous pig breeds from Viet Nam (Mong Cai, Muong Khuong, Co, Meo, Tap Na), two exotic breeds kept in Viet Nam (Large White, Landrace), three European commercial breeds (Pietrain, Landrace, Large White), and European Wild Boar were chosen for evaluation and comparison of genetic diversity. Samples and data from 317 animals were collected and ten polymorphic microsatellite loci were selected according to the recommendations of the FAO Domestic Animal Diversity Information System (DAD-IS; http://www.fao.org/dad-is/). Effective number of alleles, Polymorphism Information Content (PIC), within-breed diversity, estimated heterozygosities and tests for Hardy-Weinberg equilibrium were determined. Breed differentiation was evaluated using the fixation indices of Wright (1951). Genetic distances between breeds were estimated according to Nei (1972) and used for the construction of UPGMA dendrograms which were evaluated by bootstrapping. Heterozygosity was higher in indigenous Vietnamese breeds than in the other breeds. The Vietnamese indigenous breeds also showed higher genetic diversity than the European breeds and all genetic distances had a strong bootstrap support. The European commercial breeds, in contrast, were closely related and bootstrapping values for genetic distances among them were below 60%. European Wild Boar displayed closer relation with commercial breeds of European origin than with the native breeds from Viet Nam. This study is one of the first to contribute to a genetic characterization of autochthonous Vietnamese pig breeds and it clearly demonstrates that these breeds harbour a rich reservoir of genetic diversity. (author)
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Genetic diversity and relationships of Vietnamese and European pig breeds
International Nuclear Information System (INIS)
Thuy, N.T.D.; Melchinger, E.; Kuss, A.W.; Peischl, T.; Bartenschlager, H.; Geldermann, H.; Cuong, N.V.
2005-01-01
Indigenous resources of the Asian pig population are less defined and only rarely compared with European breeds. In this study, five indigenous pig breeds from Viet Nam (Mong Cai, Muong Khuong, Co, Meo, Tap Na), two exotic breeds kept in Viet Nam (Large White, Landrace), three European commercial breeds (Pietrain, Landrace, Large White), and European Wild Boar were chosen for evaluation and comparison of genetic diversity. Samples and data from 317 animals were collected and ten polymorphic microsatellite loci were selected according to the recommendations of the FAO Domestic Animal Diversity Information System (DAD-IS; http://www.fao.org/dad-is/). Effective number of alleles, Polymorphism Information Content (PIC), within-breed diversity, estimated heterozygosities and tests for Hardy-Weinberg equilibrium were determined. Breed differentiation was evaluated using the fixation indices of Wright (1951). Genetic distances between breeds were estimated according to Nei (1972) and used for the construction of UPGMA dendrograms which were evaluated by bootstrapping. Heterozygosity was higher in indigenous Vietnamese breeds than in the other breeds. The Vietnamese indigenous breeds also showed higher genetic diversity than the European breeds and all genetic distances had a strong bootstrap support. The European commercial breeds, in contrast, were closely related and bootstrapping values for genetic distances among them were below 60%. European Wild Boar displayed closer relation with commercial breeds of European origin than with the native breeds from Viet Nam. This study is one of the first to contribute to a genetic characterization of autochthonous Vietnamese pig breeds and it clearly demonstrates that these breeds harbour a rich reservoir of genetic diversity. (author)
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2010-03-05
... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-71,602] Cooper Tools--Sumter, Cooper Tools Divisions, a Subsidiary of Cooper Industries, Inc., Including On-Site Leased Workers From... January 26, 2010, applicable to workers of Cooper Tools--Sumter, Cooper Tools Division, a subsidiary of...
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Maternal genealogical patterns of chicken breeds sampled in Europe.
Lyimo, C M; Weigend, A; Msoffe, P L; Hocking, P M; Simianer, H; Weigend, S
2015-08-01
The aim of this study was to investigate the maternal genealogical pattern of chicken breeds sampled in Europe. Sequence polymorphisms of 1256 chickens of the hypervariable region (D-loop) of mitochondrial DNA (mtDNA) were used. Median-joining networks were constructed to establish evolutionary relationships among mtDNA haplotypes of chickens, which included a wide range of breeds with different origin and history. Chicken breeds which have had their roots in Europe for more than 3000 years were categorized by their founding regions, encompassing Mediterranean type, East European type and Northwest European type. Breeds which were introduced to Europe from Asia since the mid-19th century were classified as Asian type, and breeds based on crossbreeding between Asian breeds and European breeds were classified as Intermediate type. The last group, Game birds, included fighting birds from Asia. The classification of mtDNA haplotypes was based on Liu et al.'s (2006) nomenclature. Haplogroup E was the predominant clade among the European chicken breeds. The results showed, on average, the highest number of haplotypes, highest haplotype diversity, and highest nucleotide diversity for Asian type breeds, followed by Intermediate type chickens. East European and Northwest European breeds had lower haplotype and nucleotide diversity compared to Mediterranean, Intermediate, Game and Asian type breeds. Results of our study support earlier findings that chicken breeds sampled in Europe have their roots in the Indian subcontinent and East Asia. This is consistent with historical and archaeological evidence of chicken migration routes to Europe. © 2015 Stichting International Foundation for Animal Genetics.
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Rice breeding with induced mutations II. Report of an FAO/IAEA research co-ordination meeting
Energy Technology Data Exchange (ETDEWEB)
NONE
1970-03-01
This report contains the proceedings of the fourth meeting of participants in the FAO/IAEA Co-ordinated Program of Research on the Use of Induced Mutations in Rice Breeding, a program which was initiated in 1964. The three previous meetings were reported as follows: First: proceedings published in the International Rice Commission Newsletter, Vol. XV, No. 1 (1966). Second: report presented to the IRC Working Party meeting at Lake Charles, Louisiana, 18-30 July 1966. Third: proceedings published by the IAEA as Technical Reports Series No. 86 under the title 'Rice breeding with induced mutations'. The fourth meeting was held at Oiso, Japan, on 12-14 August 1968. Co-operators from nine countries attended, together with scientists from five other countries, the International Rice Research Institute, the Rockefeller Foundation, the International Rice Commission, and the FAO and IAEA. In addition, a number of scientists from the host country were present. The purpose of the meeting was to present reports on research related to or carried out under the co-ordinated program in 1967/68, to review and co-ordinate research plans for 1968/69, and to draw up technical recommendations for future work.
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Breeding biology of House Crows ( Corvus splendens ) in Durban ...
African Journals Online (AJOL)
Details of nestling growth, and fledging and post-fledging dependence periods, are provided. Breeding success was relatively poor. Early breeding attempts were more successful than late breeding attempts. Breeding failure was suspected, or known, to be associated with observer disturbance, egg breakage, failure of ...
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Kahi, A.K.; Koskey, I.S.; Cardoso, V.L.; Arendonk, van J.A.M.
1998-01-01
The ranking of genotypes (i.e., breeds and breed crosses) for economic performance depends on the production circumstances of the herd and the criteria for economic evaluation. In this study, the effects of evaluation criteria and production circumstance are quantified using data from the literature
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Shoji, A; Aris-Brosou, S; Culina, A; Fayet, A; Kirk, H; Padget, O; Juarez-Martinez, I; Boyle, D; Nakata, T; Perrins, C M; Guilford, T
2015-10-01
Inter-seasonal events are believed to connect and affect reproductive performance (RP) in animals. However, much remains unknown about such carry-over effects (COEs), in particular how behaviour patterns during highly mobile life-history stages, such as migration, affect RP. To address this question, we measured at-sea behaviour in a long-lived migratory seabird, the Manx shearwater (Puffinus puffinus) and obtained data for individual migration cycles over 5 years, by tracking with geolocator/immersion loggers, along with 6 years of RP data. We found that individual breeding and non-breeding phenology correlated with subsequent RP, with birds hyperactive during winter more likely to fail to reproduce. Furthermore, parental investment during one year influenced breeding success during the next, a COE reflecting the trade-off between current and future RP. Our results suggest that different life-history stages interact to influence RP in the next breeding season, so that behaviour patterns during winter may be important determinants of variation in subsequent fitness among individuals. © 2015 The Authors.
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Genetic diversity and population structure of 20 North European cattle breeds
DEFF Research Database (Denmark)
kantanen, J; Olsaker, Ingrid; Holm, Lars-Erik
2000-01-01
Blood samples were collected from 743 animals from 15 indigenous, 2 old imported, and 3 commercial North European cattle breeds. The samples were analyzed for 11 erythrocyte antigen systems, 8 proteins, and 10 microsatellites, and used to assess inter- and intrabreed genetic variation and genetic......, allelic diversity has been reduced in several breeds, which was explained by limited effective population sizes over the course of man-directed breed development and demographic bottlenecks of indigenous breeds. A tree showing genetic relationships between breeds was constructed from a matrix of random...... drift-based genetic distance estimates. The breeds were classified on the basis of the tree topology into four major breed groups, defined as Northern indigenous breeds, Southern breeds, Ayrshire and Friesian breeds, and Jersey. Grouping of Nordic breeds was supported by documented breed history...
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Inventory analysis of West African cattle breeds
International Nuclear Information System (INIS)
Belemsaga, D.M.A.; Lombo, Y.; Sylla, S.; Thevenon, S.
2005-01-01
The improvement of livestock productivity and the preservation of their genetic diversity to allow breeders to select animals adapted to environmental changes, diseases and social needs, require a detailed inventory and genetic characterization of domesticated animal breeds. Indeed, in developing countries, the notion of breed is not clearly defined, as visual traits are often used and characterization procedures are often subjective. So it is necessary to upgrade the phenotypic approach using genetic information. At CIRDES, a regional centre for subhumid livestock research and development, such studies have been conducted. This paper focuses on cattle breed inventory in seven countries of West Africa as a tool for genetic research on cattle improvement. Data collection was done using a bibliographical study, complemented by in situ investigations. According to phenotypic description and concepts used by indigenous livestock keepers, 13 local cattle breeds were recognized: N'dama, Kouri, the Baoule-Somba group, the Lagoon cattle group, zebu Azawak, zebu Maure, zebu Touareg, zebu Goudali, zebu Bororo, zebu White Fulani, zebu Djelli, zebu Peuhl soudanien and zebu Gobra (Toronke). Nine exotic breeds, (American Brahman, Gir, Girolando, Droughtmaster, Santa Gertrudis, Holstein, Montbeliarde, Jersey and Brown Swiss) and five typical cross-breeds (Holstein x Goudali; Montbeliarde x Goudali; Holstein x Azawak; Brown Swiss x Azawak; and Brown Swiss x zebu peuhl soudanien) were also found. From this initial investigation, the areas of heavy concentration of herds and the most important breeds were described. The review has also indicated the necessity for a balance between improving livestock productivity and the conservation of trypanotolerant breeds at risk of extinction in West Africa. (author)
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Genomic prediction across dairy cattle populations and breeds
DEFF Research Database (Denmark)
Zhou, Lei
Genomic prediction is successful in single breed genetic evaluation. However, there is no achievement in acoress breed prediction until now. This thesis investigated genomic prediction across populations and breeds using Chinese Holsterin, Nordic Holstein, Norwgian Red, and Nordic Red. Nordic Red...
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Testicular Histomorphometric Evaluation of Zebu Bull Breeds
Directory of Open Access Journals (Sweden)
Paulo Antônio Terrabuio Andreussi
2014-12-01
Full Text Available The objective of this study was to evaluate the quantitative histology and testicular biometrics in zebu bulls of different breeds. Testicular fragments of Nelore (n=10, Polled Nelore (n=6, Gir (n=5, Guzerat (n=5 and Tabapuã bulls (n=5 were used. The fragments were perfusion-fixed in Karnovsky solution, embedded in glycol methacrylate and stained with toluidine blue-1% sodium borate. The Nelore animals had a higher tubular volumetric proportion (85.2% and greater height of the seminiferous epithelium (73.2 µm than the Gir, Guzerat and Tabapuã breeds. The Nelore animals also had a higher volumetric proportion of Leydig cells (5.2% than the Guzerat and Tabapuã breeds. There was no significant difference for any of these parameters between the Nelore and Polled Nelore breeds. The gonadosomatic index, seminiferous tubule diameter, cross-sectional area of the seminiferous tubule and tubule length (total length and length per gram of testicular parenchyma did not vary among the breeds studied. The morphometric parameters evaluated suggested that the genetic selection applied to the Nelore and Polled Nelore breeds improved the efficiency of spermatogenesis in these breeders.
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Energy Technology Data Exchange (ETDEWEB)
Di Maio, P.A.; Arena, P.; Bongiovì, G. [Dipartimento di Energia, Ingegneria dell’Informazione e Modelli Matematici, Università di Palermo, Viale delle Scienze, Palermo (Italy); Chiovaro, P., E-mail: pierluigi.chiovaro@unipa.it [Dipartimento di Energia, Ingegneria dell’Informazione e Modelli Matematici, Università di Palermo, Viale delle Scienze, Palermo (Italy); Del Nevo, A. [ENEA Brasimone, Camugnano, BO (Italy); Forte, R. [Dipartimento di Energia, Ingegneria dell’Informazione e Modelli Matematici, Università di Palermo, Viale delle Scienze, Palermo (Italy)
2016-11-01
Highlights: • Determination of an optimal configuration for the breeder zone cooling tubes. • Attention has been focused on the toroidal–radial breeder zone cooling tubes lay out. • A theoretical-computational approach based on the Finite Element Method (FEM) has been followed, adopting a qualified commercial FEM code. • Five different configurations have been investigated to optimize the breeder zone cooling tubes arrangement fulfilling all the rules prescribed by safety codes. - Abstract: The determination of an optimal configuration for the breeder zone (BZ) cooling tubes is one of the most important issues in the DEMO Water-Cooled Lithium Lead (WCLL) breeding blanket R&D activities, since BZ cooling tubes spatial distribution should ensure an efficient heat power removal from the breeder, avoiding hotspots occurrence in the thermal field. Within the framework of R&D activities supported by the HORIZON 2020 EUROfusion Consortium action on the DEMO WCLL breeding blanket design, a campaign of parametric analyses has been launched at the Department of Energy, Information Engineering and Mathematical Models of the University of Palermo (DEIM), in close cooperation with ENEA-Brasimone, in order to assess the potential influence of BZ cooling tubes number on the thermal performances of the DEMO WCLL outboard breeding blanket equatorial module under the nominal steady state operative conditions envisaged for it, optimizing their geometric configuration and taking also into account that a large number of cooling pipes can deteriorate the tritium breeding performances of the module. In particular, attention has been focused on the toroidal-radial option for the BZ tube bundles lay-out and a parametric study has been carried out taking into account different tube bundles arrangement within the module. The study has been carried out following a numerical approach, based on the finite element method (FEM), and adopting a qualified commercial FEM code. Results
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Keijser, S F A; Meijndert, L E; Fieten, H; Carrière, B J; van Steenbeek, F G; Leegwater, P A J; Rothuizen, J; Nielen, M
2017-05-01
Current public and professional opinion is that many dog breeds suffer from health issues related to inherited diseases or extreme phenotypes. The aim of this historical comparative observational study was to evaluate the breed-related disease burden in three purebred dog populations (Chihuahua, French bulldog, Labrador retriever) and one purebred cat breed (Persian cats) in the Netherlands by comparison to a control population of mixed-breed dogs and European Shorthair cats. A qualitative query was performed, consisting of a literature review and collecting the expert opinions of University veterinary specialists, to gather insight into potential diseases of the study population. Next, a referral clinic case control study of the patients referred to specific medical disciplines in the University Clinic was performed. The odds ratio (OR) was calculated to determine the likelihood of a patient referred to a particular medical discipline being a certain breed. Together, the qualitative query and the case control study resulted in a list of potentially relevant diseases limited to five organ systems per breed. These were analysed in data from primary practices. Patient files from ten primary practices over a period of two years were manually extracted and examined. Four-hundred individual patient records per breed as well as 1000 non-breed records were randomly selected from the 10 practices, weighted per practice size. Records were then examined and the presence or absence of certain diseases was identified. To evaluate the disease burden per breed, proportional difference (PD) was estimated, as well as the animal's age at presentation in months. The results of the referral clinic case control study showed an overrepresentation (Odds Ratio>1.5) of the selected breeds in several medical specialties, while median age at presentation was in some cases significantly lower than in the non-breed animals. Results of the practice-based extended cross-sectional study showed
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Directory of Open Access Journals (Sweden)
Marie-Sophie Garcia-Heras
2016-09-01
Full Text Available The timing of breeding can strongly influence individual breeding performance and fitness. Seasonal declines in breeding parameters have been often documented in birds, particularly in the Northern Hemisphere. Fewer studies have investigated whether seasonal declines in productivity vary in space, which would have implications for a species’ population dynamics across its distributional range. We report here on variation in the timing of breeding in the Black Harrier (Circus maurus, an endangered and endemic raptor to Southern Africa. We investigated how key breeding parameters (clutch size, nesting success and productivity varied with the timing of breeding, weather conditions (rainfall and temperature and between contrasted regions (coastal vs. interior-mountain. Black Harrier onset of breeding extended over an 8-month period, with a peak of laying between mid-August and end of September. We show a marked seasonal decline in all breeding parameters. Importantly, for clutch size and productivity these seasonal declines differed regionally, being more pronounced in interior-mountain than in coastal regions, where the breeding season was overall shorter. Timing of breeding, clutch size and productivity were also partly explained by weather conditions. In coastal regions, where environmental conditions, in particular rainfall, appear to be less variable, the timing of breeding matters less for breeding output than in interior-mountain regions, and breeding attempts thus occurred over a longer period. The former areas may act as population sources and be key in protecting the long-term population viability of this threatened endemic raptor. This study provides unique evidence for a regionally variable seasonal decline in breeding performance with implications for population biology and conservation.
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Cattle breeding goals and production circumstances
Groen, A.F.
1989-01-01
This thesis gives the results of a study on the relationship between cattle breeding goals and production circumstances. The relationship between breeding goals and production circumstances mostly arises from the influences of production circumstances on the economic values of
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Hooijmeijer, Jos C. E. W.; Senner, Nathan R.; Tibbitts, T. Lee; Gill, Robert E.; Douglas, David C.; Bruinzeel, Leo W.; Wymenga, Eddy; Piersma, Theunis
2014-01-01
Conservation of long-distance migratory shorebirds is complex because these species use habitats spread across continents and hemispheres, making identification of critical habitats and potential bottlenecks in the annual cycle especially difficult. The population of Black-tailed Godwits that breeds in Western Europe, Limosa limosa limosa, has declined precipitously over the past few decades. Despite significant efforts to identify the root causes of this decline, much remains unclear. To better understand the migratory timing, use of stopover and nonbreeding sites, and the potential impact of breeding success on these parameters, we attached 15 Argos satellite transmitters and 10 geolocation tracking devices to adult godwits nearing completion of incubation at breeding sites in southwest Friesland, The Netherlands during the spring of 2009. We successfully tracked 16 adult godwits for their entire southward migration and two others for part of it. Three migration patterns and four regions of use were apparent. Most godwits left their breeding sites and proceeded south directly to stopover sites in the Mediterranean — e.g. Spain, Portugal, and Morocco — before flying on to non-breeding sites in West Africa. Other individuals spent the entire nonbreeding season in the Mediterranean. A third pattern included a few individuals that flew nonstop from their Dutch breeding sites to nonbreeding sites in West Africa. Tracking data from this study will be immediately useful for conservation efforts focused on preserving the dispersed network of sites used by godwits during their southward migration.
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Tritium breeding blanket device of D-T reactors
International Nuclear Information System (INIS)
Chevereau, G.
1984-01-01
This blanket device uses solid tritium breeding materials as those which include, in a known manner, near a neutron breeding plasma, a neutron multiplier medium and a tritium breeding medium, cooled by a cooling fluid circulation. This device is characterized by the fact that the association of the multiplier media and the tritium breeding media is realized by pellet alternated piling up of each of those both media, help in close contact on all their lateral surfaces [fr
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Directory of Open Access Journals (Sweden)
Ritu Agrawal
2016-04-01
Full Text Available Aim: This study was undertaken to compare the immunoglobulin Y (IgY level and its efficacy in laying hens of four different breeds of poultry (viz.,Vanraja, Gramapriya, BlackRock, and KalingaBrown and its relative transfer in egg yolk and chick. Materials and Methods: This study was conducted in 48 apparently healthy laying hens vaccinated with Salmonella inactivated polyvalent vaccine, eggs and progeny chicks; 12 each from four different breeds of poultry,viz.,Vanraja, Gramapriya, BlackRock, and KalingaBrown. The methodology included measurement of egg and yolk weight, total protein and IgY in egg yolk, total serum protein and IgY in breeding hens, and progeny chicks and extent of IgY transfer from hens to yolk then to chicks. Further, Salmonella-specific antibodies in breeding hens, egg yolk and progeny chicks were assessed using O and H antigen by tube agglutination test. Results: The egg weight differed nonsignificantly (p>0.05 among breeds, however, breed wise significant variation (p0.05 difference among breed was found in total protein of egg yolk and chick. The IgY concentration in hens, egg yolk and chick was found to be in the range of 5.35±0.63- 5.83±0.65, 2.3±0.1-2.6±0.2, and 1.3±0.11-1.7±0.16 mg/ml, respectively which is uniform and independent of total protein concentration at all the three levels. Significant breed variations were not observed in maternal IgY transfer from breeding hens to chicks and were 25.62±1.42-36.06±4.34% of total IgY in parent flock. Moderate to higher rate of seroprevalence with peak titers of 1:640 against Salmonella-specific antibodies was observed in only 41.6% of breeding hens. Conclusion: No significant difference in the rate of transfer of IgY was observed in four breeds studied (viz.,Vanraja, Gramapriya, BlackRock, and KalingaBrown and moderate seropositivity was detected for Salmonella-specific antibodies in progeny chicks.
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Characterization of beef cattle breeds by virtue of their performances ...
African Journals Online (AJOL)
young bulls of l6 breeds were obtained fiorn the National Beef Cattle Performance and Progeny Testing Scheme and used in this re-analysis to characterize ... breeds for their effective use in either straight breeding or cross- breeding programmes. ... Scheme as the only data source for breed characterization pur- poses.
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LINE CONSTRUCTION OF NONIUS BREED IN SLOVAKIA
Directory of Open Access Journals (Sweden)
Eva Mlyneková
2013-12-01
Full Text Available Nowadays breeding has become the problem often solved in European states and it has been paid much attention by breeding organizations. In terms of hippology as well as some urgent requirements from the side of nonius breeders we have focussed on this particular breed especially from the reason of its further survival and development in Slovakia. The aim of this paper was to evaluate the growth indicators as well as the achievement level of the stallions since 1927 to the present. Based on our research of the nonius body lines we can state that at present there are 3 stallions that are followers of the N VIII horse line founder. In general, there are 12 stallions that are active within this breed in Slovakia. It was statistically confirmed that this particular breed grew much stronger through the goal-directed breeding work, improved nutrition as well as the immediate breeding site. It was quite complicated to evaluate the performance tests because the individual indicators were significantly influenced by the subjective views of the commitee members performing the evaluation. The next factor which prevents the objective evaluation is the fact that in the period up to 1979, the performance tests were valued by the 100 point system and from the year 1980 by the 10 point system. That is why we take the performance test results into account only as supplemental ones, which can provide a kind of amendment to the observed biological parameters.
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Birds choose long-term partners years before breeding
Teitelbaum, Claire S.; Converse, Sarah J.; Mueller, Thomas
2017-01-01
Pair bonds can provide social benefits to long-term monogamous species alongside their benefits for reproduction. However, little is known about when these bonds form, in particular how long they are present before breeding. Previous studies of pair formation in long-term monogamous birds have been rather data-limited, but for many migratory birds they report pair formation on the wintering grounds. We provide the first systematic investigation of prebreeding association patterns of long-term monogamous pairs by examining entire life histories based on tracking data of migratory whooping cranes, Grus americana. We found that a substantial portion (62%) of breeding pairs started associating at least 12 months before first breeding, with 16 of 58 breeding pairs beginning to associate over 2 years before first breeding. For most pairs, these associations with future breeding partners also became unique and distinguishable from association patterns with nonpartner individuals 12 months before first breeding. In addition, 60% of pair associations began before at least one partner had reached nominal sexual maturity. Most pairs began associating in the late spring upon arrival at the summer grounds, while associations beginning at other times of the year were rare. Patterns in the associations of pairs prior to breeding can point to the potential benefits of prebreeding relationships, for instance providing support in competitive interactions or increasing partner familiarity.
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Mutation breeding in vegetable crops
International Nuclear Information System (INIS)
Yamaguchi, Takashi
1984-01-01
Vegetables breed by seeds and vegetative organs. In main vegetables, the differentiation of clopping types, the adoption of monoculture and year-round production and shipment are carried out, adapting to various socio-economic and cultivation conditions. Protected agriculture has advanced mainly for fruit vegetables, and the seeds for sale have become almost hybrid varieties. Reflecting the situation like this, the demand for breeding is diversified and characteristic, and the case of applying mutation breeding seems to be many. The present status of the mutation breeding of vegetables is not yet well under way, but about 40 raised varieties have been published in the world. The characters introduced by induced mutation and irradiation were compact form, harvesting aptitude, the forms and properties of stems and leaves, anti-lodging property, the size, form and uniformity of fruits, male sterility and so on. The radiation sources used were mostly gamma ray or X-ray, but sometimes, combined irradiation was used. As the results obtained in Japan, burdocks as an example of gamma ray irradiation to seeds, tomatoes as an example of inducing the compound resistance against disease injury and lettuces as an example of internal beta irradiation are reported. (Kako, I.)
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Induced mutations in sesame breeding
International Nuclear Information System (INIS)
Ashri, A.
2001-01-01
The scope of induced mutations in sesame (Sesamum indicum L.) breeding is reviewed. So far in Egypt, India, Iraq, Rep. of Korea, and Sri Lanka, 14 officially released varieties have been developed through induced mutations: 12 directly and 2 through cross breeding (one using the 'dt45' induced mutant from Israel). For another variety released in China there are no details. The induced mutations approach was adopted primarily in order to obtain genetic variability that was not available in the germplasm collection. The mutagens commonly applied have been gamma rays, EMS and sodium azide. Sesame seeds can withstand high mutagen doses, and there are genotypic differences in sensitivity between varieties. The mutants induced in the above named countries and others include better yield, improved seed retention, determinate habit, modified plant architecture and size, more uniform and shorter maturation period, earliness, resistance to diseases, genic male sterility, seed coat color, higher oil content and modified fatty acids composition. Some of the induced mutants have already given rise to improved varieties, the breeding value of other mutants is now being assessed and still others can serve as useful markers in genetic studies and breeding programmes. (author)
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Plant mutation breeding for crop improvement. V.2
International Nuclear Information System (INIS)
1991-01-01
This volume contains the proceedings of the final two sessions of the FAO/IAEA Symposium on Plant Mutation Breeding for Crop Improvement, focussing on mutation breeding with particular objectives and the methodology of mutation breeding. The individual contributions are indexed separately. Although a wide variety of topics is included, the emphasis is on the use of (mainly gamma) radiation to induce economically useful mutants in cereals and legumes. The results of many conventional plant breeding programs are also presented. Refs, figs and tabs
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Plant mutation breeding for crop improvement. V.1
International Nuclear Information System (INIS)
1991-01-01
This volume contains the proceedings of the first two sessions of the FAO/IAEA Symposium on Plant Mutation Breeding for Crop Improvement, focussing on mutation breeding in particular countries and crop-specific mutation breeding. The individual contributions are indexed separately. Although a wide variety of topics is included, the emphasis is on the use of (mainly gamma) radiation to induce economically useful mutants in cereals and legumes. The results of many conventional plant breeding programs are also presented. Refs, figs and tabs
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Use of induced mutations in soybean breeding
International Nuclear Information System (INIS)
Zakri, A.H.; Jalani, B.S.; Ng, K.F.
1981-01-01
Artificial induction of mutation in plants is carried out using #betta#-irradiation and ethyl metanesulphonate (EMS) to expand the genetic variability of locally-grown soybean. This aspect of mutation breeding complements of conventional breeding approach undertaken by the Joint Malaysia Soybean Breeding Project group. Recovery of agronomically-important mutants such as earliness, lateness, bigger seed size and improved plant architecture were recorded. The significance of these findings is discussed. (author)
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Savage, James L; Browning, Lucy E; Manica, Andrea; Russell, Andrew F; Johnstone, Rufus A
2017-01-01
For individuals collaborating to rear offspring, effective organization of resource delivery is difficult because each carer benefits when the others provide a greater share of the total investment required. When investment is provided in discrete events, one possible solution is to adopt a turn-taking strategy whereby each individual reduces its contribution rate after investing, only increasing its rate again once another carer contributes. To test whether turn-taking occurs in a natural cooperative care system, here we use a continuous time Markov model to deduce the provisioning behavior of the chestnut-crowned babbler ( Pomatostomus ruficeps ), a cooperatively breeding Australian bird with variable number of carers. Our analysis suggests that turn-taking occurs across a range of group sizes (2-6), with individual birds being more likely to visit following other individuals than to make repeat visits. We show using a randomization test that some of this apparent turn-taking arises as a by-product of the distribution of individual inter-visit intervals ("passive" turn-taking) but that individuals also respond actively to the investment of others over and above this effect ("active" turn-taking). We conclude that turn-taking in babblers is a consequence of both their individual provisioning behavior and deliberate response rules, with the former effect arising through a minimum interval required to forage and travel to and from the nest. Our results reinforce the importance of considering fine-scale investment dynamics when studying parental care and suggest that behavioral rules such as turn-taking may be more common than previously thought. Caring for offspring is a crucial stage in the life histories of many animals and often involves conflict as each carer typically benefits when others contribute a greater share of the work required. One way to resolve this conflict is to monitor when other carers contribute and adopt a simple "turn-taking" rule to ensure
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Breed predisposition to canine gastric carcinoma
DEFF Research Database (Denmark)
Seim-Wikse, Tonje; Jörundsson, Einar; Nødtvedt, Ane
2013-01-01
Previous research has indicated a breed predisposition to gastric carcinoma in dogs. However, results to date are inconsistent since several studies have failed to prove such a predisposition. Better knowledge of breeds at risk could facilitate early detection of gastric carcinoma in dogs. The ai...
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Managing meiotic recombination in plant breeding
Wijnker, T.G.; Jong, de J.H.S.G.M.
2008-01-01
Crossover recombination is a crucial process in plant breeding because it allows plant breeders to create novel allele combnations on chromosomes that can be used for breeding superior F1 hybrids. Gaining control over this process, in terms of increasing crossover incidence, altering crossover
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In vitro technology for mutation breeding
International Nuclear Information System (INIS)
1986-10-01
The ultimate aim of the Co-ordinated Research Programme on In Vitro Technology for Mutation Breeding is to provide new effective tools for plant breeders to construct new cultivars, thus increasing agricultural production of food, feed and industrial raw material, particularly in developing countries. The participants of the research co-ordination meetings considered the potential of new advances of agricultural biotechnology, especially the use of in vitro techniques for mutation breeding. They discussed and co-ordinated plans in conjunction with the impact on plant breeding of novel technologies, such as use of somaclonal variation, cell hybridization and molecular genetics
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Emperor penguins breeding on iceshelves.
Directory of Open Access Journals (Sweden)
Peter T Fretwell
Full Text Available We describe a new breeding behaviour discovered in emperor penguins; utilizing satellite and aerial-survey observations four emperor penguin breeding colonies have been recorded as existing on ice-shelves. Emperors have previously been considered as a sea-ice obligate species, with 44 of the 46 colonies located on sea-ice (the other two small colonies are on land. Of the colonies found on ice-shelves, two are newly discovered, and these have been recorded on shelves every season that they have been observed, the other two have been recorded both on ice-shelves and sea-ice in different breeding seasons. We conduct two analyses; the first using synthetic aperture radar data to assess why the largest of the four colonies, for which we have most data, locates sometimes on the shelf and sometimes on the sea-ice, and find that in years where the sea-ice forms late, the colony relocates onto the ice-shelf. The second analysis uses a number of environmental variables to test the habitat marginality of all emperor penguin breeding sites. We find that three of the four colonies reported in this study are in the most northerly, warmest conditions where sea-ice is often sub-optimal. The emperor penguin's reliance on sea-ice as a breeding platform coupled with recent concerns over changed sea-ice patterns consequent on regional warming, has led to their designation as "near threatened" in the IUCN red list. Current climate models predict that future loss of sea-ice around the Antarctic coastline will negatively impact emperor numbers; recent estimates suggest a halving of the population by 2052. The discovery of this new breeding behaviour at marginal sites could mitigate some of the consequences of sea-ice loss; potential benefits and whether these are permanent or temporary need to be considered and understood before further attempts are made to predict the population trajectory of this iconic species.
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Variation in the prion protein sequence in Dutch goat breeds.
Windig, J J; Hoving, R A H; Priem, J; Bossers, A; van Keulen, L J M; Langeveld, J P M
2016-10-01
Scrapie is a neurodegenerative disease occurring in goats and sheep. Several haplotypes of the prion protein increase resistance to scrapie infection and may be used in selective breeding to help eradicate scrapie. In this study, frequencies of the allelic variants of the PrP gene are determined for six goat breeds in the Netherlands. Overall frequencies in Dutch goats were determined from 768 brain tissue samples in 2005, 766 in 2008 and 300 in 2012, derived from random sampling for the national scrapie surveillance without knowledge of the breed. Breed specific frequencies were determined in the winter 2013/2014 by sampling 300 breeding animals from the main breeders of the different breeds. Detailed analysis of the scrapie-resistant K222 haplotype was carried out in 2014 for 220 Dutch Toggenburger goats and in 2015 for 942 goats from the Saanen derived White Goat breed. Nine haplotypes were identified in the Dutch breeds. Frequencies for non-wild type haplotypes were generally low. Exception was the K222 haplotype in the Dutch Toggenburger (29%) and the S146 haplotype in the Nubian and Boer breeds (respectively 7 and 31%). The frequency of the K222 haplotype in the Toggenburger was higher than for any other breed reported in literature, while for the White Goat breed it was with 3.1% similar to frequencies of other Saanen or Saanen derived breeds. Further evidence was found for the existence of two M142 haplotypes, M142 /S240 and M142 /P240 . Breeds vary in haplotype frequencies but frequencies of resistant genotypes are generally low and consequently selective breeding for scrapie resistance can only be slow but will benefit from animals identified in this study. The unexpectedly high frequency of the K222 haplotype in the Dutch Toggenburger underlines the need for conservation of rare breeds in order to conserve genetic diversity rare or absent in other breeds. © 2016 Blackwell Verlag GmbH.
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Characterization of four indigenous sheep breeds of Balochistan ...
African Journals Online (AJOL)
Characterization of four indigenous sheep breeds of Balochistan, Pakistan by random amplified polymorphic DNAs. ... The highest number of polymorphic loci 40 was observed in the Mengali breed, while the lowest 28 was in Balochi. Further, 33 and 31 polymorphic loci were seen in Beverigh and Harnai breeds, ...
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Natural immunity factors in Polish mixed breed rabbits.
Tokarz-Deptuła, B; Niedźwiedzka-Rystwej, P; Adamiak, M; Hukowska-Szematowicz, B; Trzeciak-Ryczek, A; Deptuła, W
2015-01-01
Mixed-breed rabbits in Poland are widely used for diagnostic and scientific research and as utility animals, therefore there is a need to know their immunological status, as well as their haematological status. In this study natural immunity factors were analyzed in Polish mixed-breed rabbits and Polish mixed-breed rabbits with addition of blood of meet-breed, considering the impact of sex and season of the year (spring, summer, autumn, winter) using measurement of non-specific cellular and humoral immunity parameters in peripheral blood. The study has revealed that there is a variety between the two commonly used mixed-breed types of rabbits, especially when sex and season is concerned, which is crucial for using these animals in experiments.
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Applying Mendelian rules in rapeseed (Brassica napus breeding
Directory of Open Access Journals (Sweden)
Marjanović-Jeromela Ana
2016-01-01
Full Text Available Rapeseed is one of the most important sources of edible oil, raw material for industry, as well as feed. The yield and quality of rapeseed have significantly been improved in recent decades as a result of intensive breeding and optimized production technology. The application of Mendel's rules in introducing monogenic traits has also contributed to success in rapeseed breeding. Rule 1, which refers to the uniformity of F1 generation, is now the basis of widespread development of rapeseed hybrids. Rule 2, dealing with genetic segregation in the F2 generation, is the basis for understanding the process of breeding lines. Rule 3, regarding the independent segregation of genes and traits, while exempting linked traits, is the basis of combining different desirable properties by selection. In the last few decades, the systematic use of Mendel's rules has contributed to the improvement of many properties of rapeseed, including tolerance to biotic and abiotic stress, yield and seed quality. Particular progress has been made in breeding for resistance to diseases, including the identification of molecular markers for marker-assisted selection. The next objective of rapeseed breeding is to create varieties with improved tolerance to environmental stress (e.g. frost, heat, and drought. Based on Mendel's rules, classical breeding methods and the latest developments in the field of molecular genetics and breeding, future progress is expected in the field of rapeseed breeding with an emphasis on polygenic, quantitative traits such as biomass, seed, and oil yield.
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Plant Breeding by Using Radiation Mutation
International Nuclear Information System (INIS)
Kang, Si Yong; Kim, Dong Sub; Lee, Geung Joo
2007-06-01
A mutation breeding is to use physical or chemical mutagens to induce mutagenesis, followed by individual selections with favorable traits. The mutation breeding has many advantages over other breeding methods, which include the usefulness for improving one or two inferior characteristics, applications to broad species with different reproductive systems or to diverse plant materials, native or plant introduction with narrow genetic background, time and cost-effectiveness, and valuable mutant resources for genomic researches. Recent applications of the radiation breeding techniques to developments of flowering plants or food crops with improved functional constituents heightened the public's interests in agriculture and in our genetic resources and seed industries. The goals of this project, therefore, include achieving advances in domestic seed industries and agricultural productivities by developing and using new radiation mutants with favored traits, protecting an intellectual property right of domestic seeds or germplasm, and sharing the valuable mutants and mutated gene information for the genomic and biotech researches that eventually leads to economic benefits
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Manual on mutation breeding. 2. ed.
International Nuclear Information System (INIS)
1977-01-01
The manual is a compilation of work done on the use of induced mutations in plant breeding, and presents general methods and techniques in this field. The use of chemical mutagens and ionizing radiations (X-rays, gamma rays, α- and β-particles, protons, neutrons) are described as well as the effects of these mutagens. The different types of mutations achieved can be divided into genome mutations, chromosome mutations and extra nuclear mutations. Separate chapters deal with mutation techniques in breeding seed-propagated species and asexually propagated plants (examples of development of cultivars given). Plant characters which can be improved by mutation breeding include yield, ripening time, growth habit, disease resistance and tolerance to environmental factors (temperature, salinity etc.). The use of mutagens for some specific plant breeding problems is discussed and attention is also paid to somatic cell genetics in connection with induced mutations. The manual contains a comprehensive bibliography (60 p. references) and a subject index
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Plant Breeding by Using Radiation Mutation
Energy Technology Data Exchange (ETDEWEB)
Kang, Si Yong; Kim, Dong Sub; Lee, Geung Joo (and others)
2007-06-15
A mutation breeding is to use physical or chemical mutagens to induce mutagenesis, followed by individual selections with favorable traits. The mutation breeding has many advantages over other breeding methods, which include the usefulness for improving one or two inferior characteristics, applications to broad species with different reproductive systems or to diverse plant materials, native or plant introduction with narrow genetic background, time and cost-effectiveness, and valuable mutant resources for genomic researches. Recent applications of the radiation breeding techniques to developments of flowering plants or food crops with improved functional constituents heightened the public's interests in agriculture and in our genetic resources and seed industries. The goals of this project, therefore, include achieving advances in domestic seed industries and agricultural productivities by developing and using new radiation mutants with favored traits, protecting an intellectual property right of domestic seeds or germplasm, and sharing the valuable mutants and mutated gene information for the genomic and biotech researches that eventually leads to economic benefits.
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Theodoridis, A; Ragkos, A; Rose, G; Roustemis, D; Arsenos, G
2017-11-16
In this study, the economic values for production and functional traits of dairy sheep are estimated through the application of a profit function model using farm-level technical and economic data. The traits incorporated in the model were milk production, prolificacy, fertility, milking speed, longevity and mastitis occurrence. The economic values for these traits were derived as the approximate partial derivative of the specified profit function. A sensitivity analysis was also conducted in order to examine how potential changes in input and output prices would affect the breeding goal. The estimated economic values of the traits revealed their economic impact on the definition of the breeding goal for the specified production system. Milk production and fertility had the highest economic values (€40.30 and €20.28 per standard genetic deviation (SDa)), while, mastitis only had a low negative value of -0.57 €/SDa. Therefore, breeding for clinical mastitis will have a minor impact on farm profitability because it affects a small proportion of the flock and has low additive variance. The production traits, which include milk production, prolificacy and milking speed, contributed most to the breeding goal (70.0%), but functional traits still had a considerable share (30.0%). The results of this study highlight the importance of the knowledge of economic values of traits in the design of a breeding program. It is also suggested that the production and functional traits under consideration can be categorized as those which can be efficiently treated through genetic improvement (e.g. milk production and fertility) while others would be better dealt with through managerial interventions (e.g. mastitis occurrence). Also, sub-clinical mastitis that affects a higher proportion of flocks could have a higher contribution to breeding goals.
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DEFF Research Database (Denmark)
Bigi, D.; Marelli, S. P.; Randi, Ettore
2015-01-01
-defined cosmopolitan dog breeds. As the Border Collie seems closer to the Italian breeds than the other cosmopolitan shepherd dogs considered here, a possible utilization of this breed to improve working performance in Italian traditional working shepherd dogs cannot be ignored. The data and information found here can...
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Directory of Open Access Journals (Sweden)
Yuichi Takeuchi
Full Text Available The scale-eating cichlid Perissodus microlepis with asymmetric mouth is an attractive model of behavioral laterality: each adult tears off scales from prey fishes' left or right flanks according to the direction in which its mouth is skewed. To investigate the development of behavioral laterality and mouth asymmetry, we analyzed stomach contents and lower jaw-bone asymmetry of various-sized P. microlepis (22 ≤ SL<115 mm sampled in Lake Tanganyika. The shapes of the pored scales found in each specimen's stomach indicated its attack side preference. Early-juvenile specimens (SL<45 mm feeding mainly on zooplankton exhibited slight but significant mouth asymmetry. As the fish acquired scale-eating (45 mm ≤ SL, attack side preference was gradually strengthened, as was mouth asymmetry. Among size-matched individuals, those with more skewed mouths ate more scales. These findings show that behavioral laterality in scale-eating P. microlepis is established in association with development of mouth asymmetry which precedes the behavioral acquisition, and that this synergistic interaction between physical and behavioral literalities may contribute to efficient scale-eating.
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Mutations induced in plant breeding
International Nuclear Information System (INIS)
Barriga B, P.
1984-01-01
The most significant aspects of the use of ionizing radiations in plant breeding are reviewed. Aspects such as basic principles of mutation, expression and selection in obtention of mutants, methods for using induced mutations and sucess achieved with this methodology in plant breeding are reviewed. Results obtained in a program of induced mutation on wheat for high content of protein and lysine at the Universidad Austral de Chile are presented. (Author)
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Mutations induced in plant breeding
Energy Technology Data Exchange (ETDEWEB)
Barriga B, P. (Universidad Austral de Chile, Valdivia. Inst. de Produccion y Sanidad Vegetal)
1984-10-01
The most significant aspects of the use of ionizing radiations in plant breeding are reviewed. Aspects such as basic principles of mutation, expression and selection in obtention of mutants, methods for using induced mutations and sucess achieved with this methodology in plant breeding are reviewed. Results obtained in a program of induced mutation on wheat for high content of protein and lysine at the Universidad Austral de Chile are presented.
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Breed traceability of buffalo meat using microsatellite genotyping technique.
Kannur, Bheemashankar H; Fairoze, Md Nadeem; Girish, P S; Karabasanavar, Nagappa; Rudresh, B H
2017-02-01
Although buffalo has emerged as a major meat producing animal in Asia, major research on breed traceability has so far been focused on cattle (beef). This research gap on buffalo breed traceability has impelled development and validation of buffalo breed traceability using a set of eight microsatellite (STR) markers in seven Indian buffalo breeds (Bhadawari, Jaffaarabadi, Murrah, Mehsana, Nagpuri, Pandharpuri and Surti). Probability of sharing same profile by two individuals at a specific locus was computed considering different STR numbers, allele pooling in breed and population. Match probabilities per breed were considered and six most polymorphic loci were genotyped. Out of eight microsatellite markers studied, markers CSSMO47, DRB3 and CSSM060 were found most polymorphic. Developed technique was validated with known and unknown, blood and meat samples; wherein, samples were genetically traced in 24 out of 25 samples tested. Results of this study showed potential applications of the methodology and encourage other researchers to address the problem of buffalo traceability so as to create a world-wide archive of breed specific genotypes. This work is the first report of breed traceability of buffalo meat utilizing microsatellite genotyping technique.
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Hopperdietzel, C; Hirschberg, R M; Hünigen, H; Wolter, J; Richardson, K; Plendl, J
2014-11-01
The primary objectives of this study were to document the macroscopic and histological structure of the alimentary tract (AT) of the convict cichlid Amatitlania nigrofasciata, because there are no data available for this omnivorous freshwater fish of the family Cichlidae. The morphology of the AT of A. nigrofasciata resembles that of related species. While having morphological criteria of the AT typical of most omnivorous fishes, such as a blind sac stomach and medium length intestine, A. nigrofasciata also has some structural peculiarities: the oesophagus is lined by a uniform stratified squamous epithelial layer with interspersed goblet cells along its entire length. Additionally, it has well-developed layers of the tunica muscularis including muscle fibre bundles that ascend into its mucosal folds. Occasionally, taste buds are present. In the transitional area between oesophagus and stomach, a prominent torus-like closure device is present. The mucosa of the stomach cannot be divided into different regions according to mucosal and morphological properties. The simple pattern of intestinal loops of A. nigrofasciata has few variations, irrespective of sex, mass and length of the individual fish. The first segment of the intestine is characterized by the largest mucososerosal ratio and the most complex mucosal surface architecture. A distinction of midgut and hindgut was not possible in A. nigrofasciata due to lack of defining structural components as described for other fish species. © 2014 The Fisheries Society of the British Isles.
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International Nuclear Information System (INIS)
2008-01-01
In this chapter international cooperation of the Division for Radiation Safety, NPP Decommissioning and Radwaste Management of the VUJE, a. s. is presented. Very important is cooperation with the International Atomic Energy Agency. This cooperation has various forms - national and regional projects of technical cooperation, coordinated research activities, participation of our experts in preparation of the IAEA documentation etc.
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Breeding of speciality maize for industrial purposes
Pajić Zorica; Radosavljević Milica; Filipović Milomir; Todorović Goran; Srdić Jelena; Pavlov Milovan
2010-01-01
The breeding programme on speciality maize with specific traits was established at the Maize Research Institute, Zemun Polje, several decades ago. The initial material was collected, new methods applying to breeding of speciality maize, i.e. popping maize, sweet maize and white-seeded maize, were introduced. The aim was to enhance and improve variability of the initial material for breeding these three types of maize. Then, inbred lines of good combining abilities were developed and used as c...
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Plant breeding and genetics newsletter. No. 12
Energy Technology Data Exchange (ETDEWEB)
NONE
2004-01-01
The activities of the Plant Breeding and Genetics sub-Programme concentrated, during the last six months, on organization of a new Coordinated Research Programmes and numerous training courses. To establish and implement the CRP on Effect of Mutagenic Agents on DNA Sequence in Plants a consultants meeting was held in Vienna, July 2003. As a result is was possible to implement this CRP with the participation of 12 institutes from nine.countries. Similarly, another consultant meeting was held in November to initiate a new CRP on Identification and pyramiding of genes responsible for crop quality characters and resistance to quality affecting stresses. It is expected that the CRP will be implemented in the beginning of 2004. Rapid development of molecular markers technology generated strong interest in identification and characterization of mutated genes. To meet this expectation numerous training courses and workshops were organized in the second half of the year, mainly related to regional Technical Cooperation projects implemented in Asia and Africa. Among them were training courses on: Application of induced mutations and biotechnology for crop improvement, organized by Horticultural Crop Research and Development Institute in Peradeniya, Sri Lanka; Selection methods for low phytic acid mutants in rice, Hangzhou, China; Methodology for multi-location trials and selection of mutants tolerant to abiotic stresses, ICRISAT, India standardization of crop breeding methods for the improvement of drought tolerance, Lusaka, Zambia; First workshop on Improvement of plant salt tolerance for sustainable food and feed production in saline lands, Bangkok, Thailand. It was also possible to organize the 3rd Interregional Training Course on Mutant Germplasm Characterization using Molecular Markers. Twenty participants from all regions of the world participated in this event organized as usually in Seibersdorf, Austria. The last two years we have been very much involved in
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Plant breeding and genetics newsletter. No. 12
International Nuclear Information System (INIS)
2004-01-01
The activities of the Plant Breeding and Genetics sub-Programme concentrated, during the last six months, on organization of a new Coordinated Research Programmes and numerous training courses. To establish and implement the CRP on Effect of Mutagenic Agents on DNA Sequence in Plants a consultants meeting was held in Vienna, July 2003. As a result is was possible to implement this CRP with the participation of 12 institutes from nine.countries. Similarly, another consultant meeting was held in November to initiate a new CRP on Identification and pyramiding of genes responsible for crop quality characters and resistance to quality affecting stresses. It is expected that the CRP will be implemented in the beginning of 2004. Rapid development of molecular markers technology generated strong interest in identification and characterization of mutated genes. To meet this expectation numerous training courses and workshops were organized in the second half of the year, mainly related to regional Technical Cooperation projects implemented in Asia and Africa. Among them were training courses on: Application of induced mutations and biotechnology for crop improvement, organized by Horticultural Crop Research and Development Institute in Peradeniya, Sri Lanka; Selection methods for low phytic acid mutants in rice, Hangzhou, China; Methodology for multi-location trials and selection of mutants tolerant to abiotic stresses, ICRISAT, India standardization of crop breeding methods for the improvement of drought tolerance, Lusaka, Zambia; First workshop on Improvement of plant salt tolerance for sustainable food and feed production in saline lands, Bangkok, Thailand. It was also possible to organize the 3rd Interregional Training Course on Mutant Germplasm Characterization using Molecular Markers. Twenty participants from all regions of the world participated in this event organized as usually in Seibersdorf, Austria. The last two years we have been very much involved in
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English, Sinead; Bateman, Andrew W; Mares, Rafael; Ozgul, Arpat; Clutton-Brock, Tim H
2014-03-01
Resource availability plays a key role in driving variation in somatic growth and body condition, and the factors determining access to resources vary considerably across life stages. Parents and carers may exert important influences in early life, when individuals are nutritionally dependent, with abiotic environmental effects having stronger influences later in development as individuals forage independently. Most studies have measured specific factors influencing growth across development or have compared relative influences of different factors within specific life stages. Such studies may not capture whether early-life factors continue to have delayed effects at later stages, or whether social factors change when individuals become nutritionally independent and adults become competitors for, rather than providers of, food. Here, we examined variation in the influence of the abiotic, social and maternal environment on growth across life stages in a wild population of cooperatively breeding meerkats. Cooperatively breeding vertebrates are ideal for investigating environmental influences on growth. In addition to experiencing highly variable abiotic conditions, cooperative breeders are typified by heterogeneity both among breeders, with mothers varying in age and social status, and in the number of carers present. Recent rainfall had a consistently marked effect on growth across life stages, yet other seasonal terms only influenced growth during stages when individuals were growing fastest. Group size and maternal dominance status had positive effects on growth during the period of nutritional dependence on carers, but did not influence mass at emergence (at 1 month) or growth at independent stages (>4 months). Pups born to older mothers were lighter at 1 month of age and subsequently grew faster as subadults. Males grew faster than females during the juvenile and subadult stage only. Our findings demonstrate the complex ways in which the external environment
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Plant breeding and genetics newsletter. No. 17, July 2006
International Nuclear Information System (INIS)
2006-07-01
The Plant Breeding and Genetics (PBG) Section of the Joint FAO/IAEA Programme (NAFA/AGE) recently implemented two Research Coordination Meetings (RCMs). Particular attention was given to the first RCM of the Coordinated Research Project (CRP) on Assessment of Nutrients Uptake from Bio-fortified Crops in Populations from Developing Countries, Vienna, Austria, 17-19 May 2006, which was co-organized with our nutritionist colleagues from the Division of Human Health, Nuclear Applications Department (NAHU), and sponsored by Harvest Plus. Hidden hunger and enhancing crop quality for nutrition will be given increased attention in the new biennium 2008-2009. We encourage you to share your input with us on this subject. Several training courses were implemented in the framework of different Technical Cooperation (TC) projects. Details about these activities are covered in this issue of the Newsletter. A highlight of these activities, as in every year since 2001, was the Inter-regional Training Course on Mutant Germplasm Characterization using Molecular Markers at the Seibersdorf Laboratories, Seibersdorf, Austria, 14 May to 16 June 2006
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Effect of breed and feeding on the carcass characteristics of the Chilote breed lamb
Directory of Open Access Journals (Sweden)
Jorge Ramírez-Retamal
2013-03-01
Full Text Available The Chilote sheep has been developed in an isolated environment, based on grazing lands with low nutritive value belonging to small-scale producers, because of which there is little information about the use of this breed for meat production. The objective of this work was to determine the effects on lamb carcasses of two breeds with different productive purposes and fed on pastures with different nutritional quality. Three groups of lambs were used. The first and second groups were composed of 13 and 11 Chilote lambs respectively, and the third composed of six Suffolk Down lambs. Lambs remained with their mothers, the first group on naturalized pasture and the rest on rangeland. Animals were slaughtered at 90 d of age. Live weight, carcass weight and yield, and several zoometric parameters were determined, as well as the weight of commercial cuts and the muscle, bone and fat ratios. Hide and hoof weights were also measured. For the effect of breed, Chilote lamb is narrower (P < 0.05 than Suffolk Down, but with a higher proportion of hide (P < 0.05 and hooves (P < 0.05. The type of pasture only affected hot carcass yield, which was higher in Chilote lamb with naturalized pasture than with rangeland (P < 0.05. There were no effects of breed or pasture type on the main characteristics of the lamb carcasses.
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Characterization of the genetic profile of five Danish dog breeds
DEFF Research Database (Denmark)
Pertoldi, Cino; Kristensen, T. N.; Loeschcke, Volker
2013-01-01
This investigation presents results from a genetic characterization of 5 Danish dog breeds genotyped on the CanineHD BeadChip microarray with 170,000 SNP. The breeds investigated were 1) Danish Spitz (DS; n = 8), 2) Danish-Swedish Farm Dog (DSF; n = 18), 3) Broholmer (BR; n = 22), 4) Old Danish...... Pointing Dog (ODP; n = 24), and 5) Greenland Dog (GD; n = 23). The aims of the investigation were to characterize the genetic profile of the abovementioned dog breeds by quantifying the genetic differentiation among them and the degree of genetic homogeneity within breeds. The genetic profile...... as the degree of polymorphism (P%) ranked the dog breeds in the order DS > DSF > BR > ODP > GD. Interestingly, the breed with a tenfold higher census population size compared to the other breeds, the Greenland Dog, had the lowest within-breed genetic variation, emphasizing that census size is a poor predictor...
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Physico-chemical characteristics of Anopheles breeding sites ...
African Journals Online (AJOL)
ELO
analysis of the physicochemical parameters of the water samples was carried out in the Nigerian ... Key words: Malaria, Anopheles mosquitoes, breeding habitat, physico-chemical properties. ... Anopheles mosquito has been found to breed in.
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Breeding blanket design for ITER and prototype (DEMO) fusion reactors and breeding materials issues
Energy Technology Data Exchange (ETDEWEB)
Takatsu, H; Enoeda, M [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment
1998-03-01
Current status of the designs of the ITER breeding blanket and DEMO blankets is introduced placing emphasis on the breeding materials selection and related issues. The former design is based on the up-to-date design activities, as of October 1997, being performed jointly by Joint Central Team (JCT) and Home Teams (HT`s), while the latter is based on the DEMO blanket test module designs being proposed by each Party at the TBWG (Test Blanket Working Group) meetings. (J.P.N.)
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Current status and research of plant space mutation breeding
International Nuclear Information System (INIS)
Qiu Xinmian
2011-01-01
Plant space mutation breeding and discussed themechanism of plant space mutagenesis. The variations of organisms were induced by the comprehensive effects of high vacuum, microgravity,incense radiat ion and so on. The application of space mutation breeding and inheritance in specially good grmplasm material in China were well summarized. The prospects of space mutat ion breeding was described. The space mutagenesis will provided a new way for the future breeding. (author)
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Breed differences in natriuretic peptides in healthy dogs
DEFF Research Database (Denmark)
Sjöstrand, K.; Wess, G.; Ljungvall, I.
2014-01-01
BACKGROUND: Measurement of plasma concentration of natriuretic peptides (NPs) is suggested to be of value in diagnosis of cardiac disease in dogs, but many factors other than cardiac status may influence their concentrations. Dog breed potentially is 1 such factor. OBJECTIVE: To investigate breed...... variation in plasma concentrations of pro-atrial natriuretic peptide 31-67 (proANP 31-67) and N-terminal B-type natriuretic peptide (NT-proBNP) in healthy dogs. ANIMALS: 535 healthy, privately owned dogs of 9 breeds were examined at 5 centers as part of the European Union (EU) LUPA project. METHODS: Absence...... the median concentration in Doberman Pinschers. CONCLUSIONS AND CLINICAL IMPORTANCE: Considerable interbreed variation in plasma NP concentrations was found in healthy dogs. Intrabreed variation was large in several breeds, especially for NT-proBNP. Additional studies are needed to establish breed...
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Artificiat insemination vercus natural breeding in a multi.breed beef ...
African Journals Online (AJOL)
multi.breed beef herd under intensive management. A.G. Paterson, G.O. .... also the use of Kamar heat detectors have met with limited success under the .... of the positive relation- ship between lactational stress and post partum anoestrus t4.
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Mitochondrial D-loop sequence variation among Italian horse breeds
Directory of Open Access Journals (Sweden)
Zanotti Marta
2004-11-01
Full Text Available Abstract The genetic variability of the mitochondrial D-loop DNA sequence in seven horse breeds bred in Italy (Giara, Haflinger, Italian trotter, Lipizzan, Maremmano, Thoroughbred and Sarcidano was analysed. Five unrelated horses were chosen in each breed and twenty-two haplotypes were identified. The sequences obtained were aligned and compared with a reference sequence and with 27 mtDNA D-loop sequences selected in the GenBank database, representing Spanish, Portuguese, North African, wild horses and an Equus asinus sequence as the outgroup. Kimura two-parameter distances were calculated and a cluster analysis using the Neighbour-joining method was performed to obtain phylogenetic trees among breeds bred in Italy and among Italian and foreign breeds. The cluster analysis indicates that all the breeds but Giara are divided in the two trees, and no clear relationships were revealed between Italian populations and the other breeds. These results could be interpreted as showing the mixed origin of breeds bred in Italy and probably indicate the presence of many ancient maternal lineages with high diversity in mtDNA sequences.
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Population viability analysis on domestic horse breeds (Equus caballus)
DEFF Research Database (Denmark)
Thirstrup, Janne Pia; Bach, Lars; Loeschcke, Volker
2009-01-01
simulation package was used for the population viability analysis. First, we investigated the future viability of these breeds based on present demographic and environmental parameters. Second, a sensitivity analysis revealed the most important variables for the viability of these breeds. Third, we examined...... concerning reproduction of the mares had the greatest impact, with the number of mares actively breeding being the most influential on the population forecasts. The results suggest that closing the Knabstrupper studbooks can be done only if increasing the number of mares actively breeding counteracts...... the loss of genetic variation attributable to such a management strategy. It is recommended, based on these results, that the number of Frederiksborg and Knabstrupper mares actively breeding must be increased to approximately 30% in the 2 breeds that are presently using only 13%, while leaving the third...
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Home Range Size and Resource Use of Breeding and Non-breeding White Storks Along a Land Use Gradient
Directory of Open Access Journals (Sweden)
Damaris Zurell
2018-06-01
Full Text Available Biotelemetry is increasingly used to study animal movement at high spatial and temporal resolution and guide conservation and resource management. Yet, limited sample sizes and variation in space and habitat use across regions and life stages may compromise robustness of behavioral analyses and subsequent conservation plans. Here, we assessed variation in (i home range sizes, (ii home range selection, and (iii fine-scale resource selection of white storks across breeding status and regions and test model transferability. Three study areas were chosen within the Central German breeding grounds ranging from agricultural to fluvial and marshland. We monitored GPS-locations of 62 adult white storks equipped with solar-charged GPS/3D-acceleration (ACC transmitters in 2013–2014. Home range sizes were estimated using minimum convex polygons. Generalized linear mixed models were used to assess home range selection and fine-scale resource selection by relating the home ranges and foraging sites to Corine habitat variables and normalized difference vegetation index in a presence/pseudo-absence design. We found strong variation in home range sizes across breeding stages with significantly larger home ranges in non-breeding compared to breeding white storks, but no variation between regions. Home range selection models had high explanatory power and well predicted overall density of Central German white stork breeding pairs. Also, they showed good transferability across regions and breeding status although variable importance varied considerably. Fine-scale resource selection models showed low explanatory power. Resource preferences differed both across breeding status and across regions, and model transferability was poor. Our results indicate that habitat selection of wild animals may vary considerably within and between populations, and is highly scale dependent. Thereby, home range scale analyses show higher robustness whereas fine-scale resource
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Non-cooperative game theory in biology and cooperative reasoning in humans.
Kabalak, Alihan; Smirnova, Elena; Jost, Jürgen
2015-06-01
The readiness for spontaneous cooperation together with the assumptions that others share this cooperativity has been identified as a fundamental feature that distinguishes humans from other animals, including the great apes. At the same time, cooperativity presents an evolutionary puzzle because non-cooperators do better in a group of cooperators. We develop here an analysis of the process leading to cooperation in terms of rationality concepts, game theory and epistemic logic. We are, however, not attempting to reconstruct the actual evolutionary process. We rather want to provide the logical structure underlying cooperation in order to understand why cooperation is possible and what kind of reasoning and beliefs would lead to cooperative decision-making. Game theory depends on an underlying common belief in non-cooperative rationality of the players, and cooperativity similarly can utilize a common belief in cooperative rationality as its basis. We suggest a weaker concept of rational decision-making in games that encompasses both types of decision-making. We build this up in stages, starting from simple optimization, then using anticipation of the reaction of others, to finally arrive at reflexive and cooperative reasoning. While each stage is more difficult than the preceding, importantly, we also identify a reduction of complexity achieved by the consistent application of higher stage reasoning.
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Designing for cooperation - cooperating in design
DEFF Research Database (Denmark)
Kyng, Morten
1991-01-01
This article will discuss how to design computer applications that enhance the quality of work and products, and will relate the discussion to current themes in the field of Computer-Supported Cooperative Work (CSCW). Cooperation is a key element of computer use and work practice, yet here...... a specific "CSCW approach is not taken." Instead the focus is cooperation as an important aspect of work that should be integrated into most computer support efforts in order to develop successful computer support, however, other aspects such as power, conflict and control must also be considered....
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Do dogs live in joint families? Understanding allo-parental care in free-ranging dogs
Paul, Manabi; Bhadra, Anindita
2016-01-01
Cooperative breeding is an excellent example of altruistic cooperation in social groups. Domestic dogs have evolved from cooperatively hunting and breeding ancestors, but have adapted to a facultatively social scavenging lifestyle on streets, and solitary living in human homes. Pets typically breed and reproduce under human supervision, but free-ranging dogs can provide insights into the natural breeding biology of dogs. We conducted a five year long study on parental care of free-ranging dog...
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Charge breeding of intense radioactive beams
Kester, O
2001-01-01
The efficient transformation of radioactive beams by charge breeding devices will critically influence the lay-out of the post accelerator of presently built first generation radioactive ion beam (RIB) facilities as well as new second generation facilities. The size of the post-accelerator needed to bring the unstable nuclei to the energies required to study nuclear reactions depends on the charge state of the radioactive ions. The capability to raise that charge state from 1+ to n+, where n may correspond to a charge-to- mass ratio of 0.15 or higher, will therefore produce an enormous reduction in cost as well as the possibility to accelerate heavier masses. Thus the efficiency of the charge breeding scheme in comparison to the stripping scheme will be explored in the frame of the EU-network charge breeding. The two possible charge breeding schemes using either an Electron Beam Ion Source (EBIS) or an Electron Cyclotron Resonance Ion Source (ECRIS), the demands to the sources and the present status of existi...
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Horse breed discrimination using machine learning methods
Czech Academy of Sciences Publication Activity Database
Burócziová, Monika; Riha, J.
2009-01-01
Roč. 50, č. 4 (2009), s. 375-377 ISSN 1234-1983 Institutional research plan: CEZ:AV0Z50450515 Keywords : Breed discrimination * Genetics diversity * Horse breeds Subject RIV: EG - Zoology Impact factor: 1.324, year: 2009
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Dog Breed Differences in Visual Communication with Humans.
Konno, Akitsugu; Romero, Teresa; Inoue-Murayama, Miho; Saito, Atsuko; Hasegawa, Toshikazu
2016-01-01
Domestic dogs (Canis familiaris) have developed a close relationship with humans through the process of domestication. In human-dog interactions, eye contact is a key element of relationship initiation and maintenance. Previous studies have suggested that canine ability to produce human-directed communicative signals is influenced by domestication history, from wolves to dogs, as well as by recent breed selection for particular working purposes. To test the genetic basis for such abilities in purebred dogs, we examined gazing behavior towards humans using two types of behavioral experiments: the 'visual contact task' and the 'unsolvable task'. A total of 125 dogs participated in the study. Based on the genetic relatedness among breeds subjects were classified into five breed groups: Ancient, Herding, Hunting, Retriever-Mastiff and Working). We found that it took longer time for Ancient breeds to make an eye-contact with humans, and that they gazed at humans for shorter periods of time than any other breed group in the unsolvable situation. Our findings suggest that spontaneous gaze behavior towards humans is associated with genetic similarity to wolves rather than with recent selective pressure to create particular working breeds.
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The role of otolith size in hearing – Insights from cichlid fishes
Directory of Open Access Journals (Sweden)
Tanja Schulz-Mirbach
2015-10-01
Full Text Available Otolithic end organs in fishes function as accelerometers and are involved in the senses of balance and hearing (e.g. Popper et al. 2005. Otolith mass and shape are likely decisive factors influencing otolith motion, but while it is largely unknown how different shapes affect otolith movement relative to the sensory epithelium (Popper et al. 2005, greater otolith mass is predicted to result in enhanced stimulation of sensory hair cells and improved hearing (Lychakov and Rebane 2005. What few studies exist on this topic, however, yielded contradicting results in that they did or did not find a correlation between increased otolith mass and enhanced hearing (see Kéver et al. 2014. We investigated the relationship between otolith morphology (including 3D-models of otoliths based on high-resolution microCT imaging and otolith weight and hearing abilities in cichlids while comparing three species (Etroplus maculatus, Hemichromis guttatus, Steatocranus tinanti with different swimbladder morphology and hearing abilities (Schulz-Mirbach et al. 2014. We predicted Etroplus maculatus—the species that displays the best hearing sensitivities—to possess larger/heavier otoliths. As swimbladder extensions in this species are connected to the lagena, we further predicted to find heavier lagenar otoliths. Compared to H. guttatus and S. tinanti, E. maculatus showed the heaviest saccular otoliths, while lagenar otoliths were significantly thinner and lighter than in the former two species, apparently contradicting the hypothesis that the lagena and its otolith are primarily involved in improved hearing abilities. Our results support the idea that there is no ‘simple’ relationship between otolith weight, ancilliary auditory structures and hearing abilities. 3D-models of inner ears and otoliths may be ideally suited for future studies modeling complex otolith motion and thus, may provide a better understanding of how otolith morphology contributes to inner
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Development of a Worldwide Consortium on Evolutionary Participatory Breeding in Quinoa.
Murphy, Kevin M; Bazile, Didier; Kellogg, Julianne; Rahmanian, Maryam
2016-01-01
Chenopodium quinoa is gaining global importance due to its excellent protein quality and tolerance of abiotic stresses. The last 60 years have seen major strides in the expansion of quinoa crop production and experimentation. Quinoa's wide genetic diversity has led to its agronomic versatility and adaptation to different soil types, particularly saline soils, and environments with extremely variable conditions in terms of humidity, altitude, and temperature. The potential of quinoa to contribute to global food security was recognized in 2013 in the declaration of the International Year of Quinoa (IYQ). Promoting the use of improved homogeneous quinoa varieties standardized to comply with applicable norms on seeds or suited to intensified conventional agriculture farming systems may not generate the necessary resilience needed to respond to current and future global challenges. Maintaining and increasing quinoa biodiversity is imperative, as the dynamics of the global expansion of quinoa may constitute a threat to farmers if the spread is generated with a narrow genetic base. In this article, we propose that the method of evolutionary participatory breeding could be a useful tool to develop new quinoa genetic material in cooperation with farmers. We introduce preliminary results on quinoa population development with farmers in the Pacific Northwest region of the USA. We conclude that a global collaborative network on quinoa (GCN-Quinoa) could be the baseline for participatory plant breeding programs originating in developing or developed countries to meet the needs of farmers across a diversity of agronomic systems and a wide range of physical environments.
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Development of a Worldwide Consortium on Evolutionary Participatory Breeding in Quinoa
Murphy, Kevin M.; Bazile, Didier; Kellogg, Julianne; Rahmanian, Maryam
2016-01-01
Chenopodium quinoa is gaining global importance due to its excellent protein quality and tolerance of abiotic stresses. The last 60 years have seen major strides in the expansion of quinoa crop production and experimentation. Quinoa’s wide genetic diversity has led to its agronomic versatility and adaptation to different soil types, particularly saline soils, and environments with extremely variable conditions in terms of humidity, altitude, and temperature. The potential of quinoa to contribute to global food security was recognized in 2013 in the declaration of the International Year of Quinoa (IYQ). Promoting the use of improved homogeneous quinoa varieties standardized to comply with applicable norms on seeds or suited to intensified conventional agriculture farming systems may not generate the necessary resilience needed to respond to current and future global challenges. Maintaining and increasing quinoa biodiversity is imperative, as the dynamics of the global expansion of quinoa may constitute a threat to farmers if the spread is generated with a narrow genetic base. In this article, we propose that the method of evolutionary participatory breeding could be a useful tool to develop new quinoa genetic material in cooperation with farmers. We introduce preliminary results on quinoa population development with farmers in the Pacific Northwest region of the USA. We conclude that a global collaborative network on quinoa (GCN-Quinoa) could be the baseline for participatory plant breeding programs originating in developing or developed countries to meet the needs of farmers across a diversity of agronomic systems and a wide range of physical environments. PMID:27242815
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Livestock breeding for sustainability to mitigate global warming, with ...
African Journals Online (AJOL)
However, both genetic and epigenetic controls influence genetic expression and should be taken into account when formulating breeding programmes. Subsistence farmers keep livestock for multiple purposes and the formulation of breeding objectives/strategies will have to consider these dynamics. Keywords: Breeding ...
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Schaub, Michael; Jakober, Hans; Stauber, Wolfgang
2011-10-01
Demographic rates of migratory species passing through several areas during their annual cycle may be affected by environmental conditions at each of these areas. Recent studies provide evidence that their impact is not necessarily immediate, but can be delayed. We studied survival, reproductive success and arrival date at the breeding grounds of red-backed shrikes Lanius collurio, a trans-Saharan migrant, in relation to weather and vegetation on the breeding grounds, the stopover sites during migration and in the wintering areas. These environmental factors are used as proxy of the shrike's food supply. We analysed detailed demographic data of some 4,600 individuals from 25 years with multistate capture-recapture and mixed models. Survival probabilities of juveniles and breeders of both sexes varied in parallel across time, suggesting that all cohorts were sensitive to similar causes of mortality. Reproductive performance increased with temperature and decreased with rainfall on the breeding area. Moreover, it increased with vegetation cover in the Sahelian stopover area used on autumn migration suggesting a carry-over effect. Arrival date was negatively affected by spring temperatures in the breeding area. Hence, demographic rates were affected by environmental factors on the breeding grounds, but also outside and elsewhere. This suggests that the shrike's population dynamics are driven by environmental factors operating at various scales of space and time. However, only a small amount of the temporal variation in demographic rates is explained by the environmental factors considered, suggesting that additional factors, such as those operating during migration, might be important.
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Clonal forestry, heterosis and advanced-generation breeding
Energy Technology Data Exchange (ETDEWEB)
Tuskan, G.A.
1997-08-01
This report discusses the clonal planting stock offers many advantages to the forest products industry. Advanced-generation breeding strategies should be designed to maximize within-family variance and at the same time allow the capture of heterosis. Certainly there may be a conflict in the choice of breeding strategy based on the trait of interest. It may be that the majority of the traits express heterosis due to overdominance. Alternatively, disease resistance is expressed as the lack of a specific metabolite or infection court then the homozygous recessive genotype may be the most desirable. Nonetheless, as the forest products industry begins to utilize the economic advantages of clonal forestry, breeding strategies will have to be optimized for these commercial plant materials. Here, molecular markers can be used to characterize the nature of heterosis and therefore define the appropriate breeding strategy.
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Breed-Predispositions to Cancer in Pedigree Dogs
Dobson, Jane M.
2013-01-01
Cancer is a common problem in dogs and although all breeds of dog and crossbred dogs may be affected, it is notable that some breeds of pedigree dogs appear to be at increased risk of certain types of cancer suggesting underlying genetic predisposition to cancer susceptibility. Although the aetiology of most cancers is likely to be multifactorial, the limited genetic diversity seen in purebred dogs facilitates genetic linkage or association studies on relatively small populations as compared to humans, and by using newly developed resources, genome-wide association studies in dog breeds are proving to be a powerful tool for unravelling complex disorders. This paper will review the literature on canine breed susceptibility to histiocytic sarcoma, osteosarcoma, haemangiosarcoma, mast cell tumours, lymphoma, melanoma, and mammary tumours including the recent advances in knowledge through molecular genetic, cytogenetic, and genome wide association studies. PMID:23738139
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Pedigree analysis of an ostrich breeding flock
African Journals Online (AJOL)
p2492989
among dairy cattle breeds in the US was reported to be 161, 61, 65, 39 and 30 for the Ayrshire, Brown ... Knowledge of these parameters could help the industry when formulating breeding programmes. ..... In 'Ratites in a competitive world.
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Genetic resources in maize breeding
Directory of Open Access Journals (Sweden)
Anđelković Violeta
2017-01-01
Full Text Available Maize, wheat and rice are the most important cereals grown in the world. It is predicted that by 2025 maize is likely to become the crop with the greatest production globally. Conservation of maize germplasm provides the main resources for increased food and feed production. Conservation in gene banks (ex-situ is dominant strategy for maize conservation. More than 130 000 maize accessions, e.g. about 40% of total number, are stored in ten largest gene banks worldwide and Maize Research Institute Zemun Polje (MRIZP gene bank, with about 6000 accessions, is among them. Organized collecting missions started in 1961. in the former Yugoslavian territory, and up today, more than 2000 local maize landraces were stored. Pre-breeding activities that refer to identification of desirable traits from unadapted germplasm within genebank, result in materials expected to be included in breeding programs. Successful examples are LAMP, GEM and GENRES projects. At the end of XX century, at MRIZP genebank two pre-breeding activities were undertaken: eco-core and elite-core collections were created and landraces fulfilled particular criteria were chosen. In the last decade, MRIZP genebank collection was used for identification of sources for drought tolerance and improved grain quality. According to agronomic traits and general combining ability, two mini-core collections were created and included in commercial breeding programs.
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Genetic Diversity of Seven Cattle Breeds Inferred Using Copy Number Variations
Directory of Open Access Journals (Sweden)
Magretha D. Pierce
2018-05-01
Full Text Available Copy number variations (CNVs comprise deletions, duplications, and insertions found within the genome larger than 50 bp in size. CNVs are thought to be primary role-players in breed formation and adaptation. South Africa boasts a diverse ecology with harsh environmental conditions and a broad spectrum of parasites and diseases that pose challenges to livestock production. This has led to the development of composite cattle breeds which combine the hardiness of Sanga breeds and the production potential of the Taurine breeds. The prevalence of CNVs within these respective breeds of cattle and the prevalence of CNV regions (CNVRs in their diversity, adaptation and production is however not understood. This study therefore aimed to ascertain the prevalence, diversity, and correlations of CNVRs within cattle breeds used in South Africa. Illumina Bovine SNP50 data and PennCNV were utilized to identify CNVRs within the genome of 287 animals from seven cattle breeds representing Sanga, Taurine, Composite, and cross breeds. Three hundred and fifty six CNVRs of between 36 kb to 4.1 Mb in size were identified. The null hypothesis that one CNVR loci is independent of another was tested using the GENEPOP software. One hunded and two and seven of the CNVRs in the Taurine and Sanga/Composite cattle breeds demonstrated a significant (p ≤ 0.05 association. PANTHER overrepresentation analyses of correlated CNVRs demonstrated significant enrichment of a number of biological processes, molecular functions, cellular components, and protein classes. CNVR genetic variation between and within breed group was measured using phiPT which allows intra-individual variation to be suppressed and hence proved suitable for measuring binary CNVR presence/absence data. Estimate PhiPT within and between breed variance was 2.722 and 0.518 respectively. Pairwise population PhiPT values corresponded with breed type, with Taurine Holstein and Angus breeds demonstrating no between
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Breeding for behavioural change in farm animails
DEFF Research Database (Denmark)
Sandøe, Peter; D'eath, RB; Lawrence, AB
2009-01-01
In farm animal breeding, behavioural traits are rarely included in selection programmes despite their potential to improve animal production and welfare. Breeding goals have been broadened beyond production traits in most farm animal species to include health and functional traits...
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Breeding for behavioural change in farm animals
DEFF Research Database (Denmark)
D'Eath, R.B.; Conington, J.; Lawrence, A.B.
2010-01-01
In farm animal breeding, behavioural traits are rarely included in selection programmes despite their potential to improve animal production and welfare. Breeding goals have been broadened beyond production traits in most farm animal species to include health and functional traits...
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Franco, D; Rois, D; Vázquez, J A; Purriños, L; González, R; Lorenzo, J M
2012-02-01
The aim of this research was to study the Mos rooster breed growth performance, carcass, and meat quality. The breed effect (Mos vs. Sasso T-44) and finishing feed in the last month (fodder vs. corn) on animal growth, carcass characteristics, meat quality, and fatty and amino acid profiles were studied using a randomized block design with initial weight as covariance. In total, 80 roosters (n = 30 of Sasso T-44 line and n = 50 of Mos breed) were used. They were separated by breed and allocated to 2 feeding treatment groups (concentrate and corn). Each feeding treatment group consisted of 15 and 25 roosters, for Sasso T-44 line and Mos breed, respectively. Finishing feeding did not affect growth parameters in the 2 genotypes of rooster tested (P > 0.05). Nonetheless, the comparison between both types of roosters led to significant differences in growth parameters (P 0.05) were found, and as expected, carcass weight clearly differed between genotypes due to the lower growth rate of Mos roosters. However, drumstick, thigh, and wing percentages were greater in the Mos breed than in the hybrid line. In color instrumental traits, roosters feeding with corn showed breast meat with significantly (P < 0.001) higher a* and b* values than those of cocks feeding with commercial fodder. Values of shear force were less than 2 kg for both genotypes, thus it can be classified as very tender meat. Finishing with corn significantly increased (P < 0.001) the polyunsaturated fatty acid content in the breast; the Mos breed had a polyunsaturated to saturated fatty acid ratio of 0.73. The amino acid profile of the indigenous breed was not similar to that of the commercial strain. Finishing feeding treatment had a greater influence than breed effect on amino acid profile.
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Characteristics important for organic breeding of vegetable crops
Directory of Open Access Journals (Sweden)
Zdravković Jasmina
2010-01-01
Full Text Available The remarkable development and application of new genetic The Institute for Vegetable Crops possesses a rich germplasm collection of vegetables, utilized as gene resource for breeding specific traits. Onion and garlic breeding programs are based on chemical composition improvement. There are programs for identification and use of genotypes characterized by high tolerance to economically important diseases. Special attention is paid to breeding cucumber and tomato lines tolerant to late blight. As a result, late blight tolerant pickling cucumber line, as well as late blight tolerant tomato lines and hybrids are realized. Research on bean drought stress tolerance is initiated. Lettuce breeding program including research on spontaneous flora is started and interspecies hybrids were observed as possible genetic variability source. It is important to have access to a broad range of vegetable genotypes in order to meet the needs of organic agriculture production. Appreciating the concept of sustainable agriculture, it is important to introduce organic agriculture programs in breeding institutions.
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Fitness consequences of timing of migration and breeding in cormorants.
Directory of Open Access Journals (Sweden)
Phillip Gienapp
Full Text Available In most bird species timing of breeding affects reproductive success whereby early breeding is favoured. In migratory species migration time, especially arrival at the breeding grounds, and breeding time are expected to be correlated. Consequently, migration time should also have fitness consequences. However, in contrast to breeding time, evidence for fitness consequences of migration time is much more limited. Climate change has been shown to negatively affect the synchrony between trophic levels thereby leading to directional selection on timing but again direct evidence in avian migration time is scarce. We here analysed fitness consequences of migration and breeding time in great cormorants and tested whether climate change has led to increased selection on timing using a long-term data set from a breeding colony on the island of Vorsø (Denmark. Reproductive success, measured as number of fledglings, correlated with breeding time and arrival time at the colony and declined during the season. This seasonal decline became steeper during the study period for both migration and breeding time and was positively correlated to winter/spring climate, i.e. selection was stronger after warmer winters/springs. However, the increasing selection pressure on timing seems to be unrelated to climate change as the climatic variables that were related to selection strength did not increase during the study period. There is indirect evidence that phenology or abundances of preferred prey species have changed which could have altered selection on timing of migration and breeding.
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Ethical distinctions between different kinds of plant breeding
DEFF Research Database (Denmark)
Myskja, B.K.; Schouten, H.J.; Gjerris, Mickey
2015-01-01
The article discusses whether there are ethically significant distinctions between different forms of plant breeding. We distinguish different forms of plant breeding according to the kind of technology and degree of human intervention compared to plant reproduction occurring in nature. According...... differences between plant breeding methods. The framework can contribute to an improved dialogue between the scientific community and the wider public by making the scepticism towards GM-technology more intelligible....
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PUBLIC SECTOR PLANT BREEDING IN A PRIVATIZING WORLD
Thirtle, Colin G.; Srinivasan, Chittur S.; Heisey, Paul W.
2001-01-01
Intellectual property protection, globalization, and pressure on public budgets in many industrialized countries have shifted the balance of plant breeding activity from the public to the private sector. Several economic factors influence the relative shares of public versus private sector plant breeding activity, with varying results over time, over country, and over crop. The private sector, for example, dominates corn breeding throughout the industrialized world, but public and private act...
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Zoppoth, P; Koblmüller, S; Sefc, K M
2013-03-01
Whether premating isolation is achieved by male-specific, female-specific or sex-independent assortative preferences often depends on the underlying evolutionary processes. Here we test mate preferences of males presented with females of different allopatric colour variants of the cichlid fish Tropheus sp., a Lake Tanganyika endemic with rich geographical colour pattern variation, in which the strength of sexual isolation varies between populations. We conducted two-way mate choice experiments to compare behaviour of males of a red-bodied morph (population Moliro) towards females from their own population with behaviour towards females from four allopatric populations at different stages of phylogenetic and phenotypic divergence. Males courted same-population females significantly more intensely than females of other populations, and reduced their heteromorphic courtship efforts both with increasing genetic and increasing phenotypic distinctness of the females. In particular, females of a closely related red-bodied population received significantly more courtship than either genetically distinct, similarly coloured females ('Kirschfleck' morph) or genetically related, differently coloured females ('yellow-blotch' morph), both of which were courted similarly. Genetically and phenotypically distinct females (Tropheus polli) were not courted at all. Consistent with previous female-choice experiments, female courtship activity also decreased with increasing genetic distance from the males' population. Given successful experimental and natural introgression between colour morphs and the pervasive allopatry of related variants, we consider it unlikely that assortative preferences of both sexes were driven by direct selection during periods of secondary contact or, in turn, drove colour pattern differentiation in allopatry. Rather, we suggest that sexual isolation evolved as by-product of allopatric divergence. © 2012 The Authors. Journal of Evolutionary Biology © 2012
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Breeding system and pollination biology of the semidomesticated ...
African Journals Online (AJOL)
Breeding system and pollination biology of the semidomesticated fruit tree, Tamarindus indica L. (Leguminosae: Caesalpinioideae ): Implications for fruit production, selective breeding, and conservation of genetic resources.
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On the Breeds of Cattle - Historic and Current Classifications
DEFF Research Database (Denmark)
Felius, Marleen; Koolmees, Peter A; Theunissen, Bert
2011-01-01
. This is largely in agreement with the breed clusters indicated by a biochemical and molecular genetic analysis, which reflect either groups of breeds with a common geographic origin or single breeds that have expanded by export and/or crossbreeding. We propose that this information is also relevant for managing...
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Characterization of local goat breeds using RAP-DNA markers
Al-Barzinji, Yousif M. S.; Hamad, Aram O.
2017-09-01
The present study was conducted on different colors of local goat breeds. A number of 216 does were sampled from the seven groups. Genomic DNA was extracted from the blood samples. From the twenty used RAPD primers 12 of them were amplified, and presence of bands. The total fragment number of 12 primers over all the goat breed samples was 485 fragments. Out of the 485 fragments, 90 of them were Polymorphic fragments numbers (PFN). From all bands obtained, 20 of them possessed unique bands. The highest unique band was found in locus RAP 6 which has 4 unique bands, three of them in the Maraz Brown and one in the local Koor. Nei's gene diversity and Shanon's information index in this study were averaged 0.38 and 0.60, respectively. The genetic distance among several goat breeds ranged from 9.11 to 43.33%. The highest genetic distance 43.33% recorded between Maraz goat and other goat breeds and between local Koor and other goat (except Maraz goats) breeds (37.79%). However, the lowest genetic distance recorded between local white and Pnok. The distance between (local Black and Pnok) and (local Black and local white) was 22.75%. In conclusions, the high distance among these goat breeds, polymorphism and high numbers of unique bands found in present study indicates that these goat breeds have the required amount of genetic variation to made genetic improvement. This study helps us to clarify the image of the genetic diversity of the local goat breeds and the breeders can used it for mating system when need to make the crossing among these goat breeds.
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A Morphometric Survey among Three Iranian Horse Breeds with Multivariate Analysis
Directory of Open Access Journals (Sweden)
M. Hosseini
2016-12-01
Full Text Available Three Iranian horse breeds, Turkoman, Caspian, and Kurdish, are the most important Iranian horse breeds which are well known in all around of the world because of their beauty, versatility, great stamina, and intelligence. Phenotypic characterization was used to identify and document the diversity within and between distinct breeds, based on their observable attributes. Phenotypic characterization and body biometric in 23 traits were measured in 191 purebred horses belonging to three breeds, i.e. Turkoman (70 horses, Kurdish (77 horses, and Caspian (44 horses. Caspian breed was sampled from the Provinces of Alborz and Gilan. Kurdish breed was sampled from the Provinces of Kurdistan, Kermanshah, and Hamadan. Turkoman breed was sampled from the Provinces of Golestan, Markazi, and Isfahan. Multivariate analysis of variance (MANOVA was implemented. In addition, Canonical Discriminate Analysis (CDA, Principal Component Analysis (PCA, and Custer analysis were executed for assessing the relationship among the breeds. All statistical analysis was executed by SAS statistical program. The results of our investigation represented the breeds classification into 3 different classes (Caspian, Turkoman, and Kurdish based on different morphometrical traits. Caspian breed with smaller size in most variables was detached clearly from the others with more distance than Kurdish and Turkoman breeds. The result showed that the most variably trait for classification was Hind Hoof Length. Adaptation with different environments causes difference in morphology and difference among breeds. We can identify and classify domestic population using PCA, CDA, and cluster analysis.
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Study of space mutation breeding in China
International Nuclear Information System (INIS)
Wen Xianfang; Zhang Long; Dai Weixu; Li Chunhua
2004-01-01
This paper described the status of space mutation breeding in China. It emphasized that since 1978 Chinese space scientists and agricultural biologists have send 50 kg seeds of more than 70 crops including cereals, cotton, oil, vegetable, fruit and pasture to the space using the facilities such as return satellite 9 times, Shenzhou aircraft twice and high balloon 4 times. New varieties of 19 with high yield, high quality and disease-resistance, have been bred though years of breeding at the earth at more than 70 Chinese research institutes in 22 provinces. The new varieties include five rice varieties, two wheat varieties, two cotton varieties, one sweat pepper, one tomato variety, one sesame variety, three water melon varieties, three lotus varieties and one ganoderma lucidum variety. In addition more than 50 new lines and many other germplasm resources have been obtained. Study on space breeding mechanism, such as biological effect of space induction, genetic variation by cell and molecular techniques and simulated study at the earth, has been conducted, and some progresses have been achieved. Many space-breeding bases have been established in some provinces. Space varieties have been extended up to 270000 hectares, and some useful scientific achievements and social economic benefit had been made. The study of Chinese space mutation breeding is going ahead in the world. The paper also introduced the contribution and results made by return satellites of the first three generation in space science. Some basic parameters involved in the study on space mutation breeding of return satellites were listed
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Biotechnology and apple breeding in Japan
Igarashi, Megumi; Hatsuyama, Yoshimichi; Harada, Takeo; Fukasawa-Akada, Tomoko
2016-01-01
Apple is a fruit crop of significant economic importance, and breeders world wide continue to develop novel cultivars with improved characteristics. The lengthy juvenile period and the large field space required to grow apple populations have imposed major limitations on breeding. Various molecular biological techniques have been employed to make apple breeding easier. Transgenic technology has facilitated the development of apples with resistance to fungal or bacterial diseases, improved fruit quality, or root stocks with better rooting or dwarfing ability. DNA markers for disease resistance (scab, powdery mildew, fire-blight, Alternaria blotch) and fruit skin color have also been developed, and marker-assisted selection (MAS) has been employed in breeding programs. In the last decade, genomic sequences and chromosome maps of various cultivars have become available, allowing the development of large SNP arrays, enabling efficient QTL mapping and genomic selection (GS). In recent years, new technologies for genetic improvement, such as trans-grafting, virus vectors, and genome-editing, have emerged. Using these techniques, no foreign genes are present in the final product, and some of them show considerable promise for application to apple breeding. PMID:27069388
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Feilich, Kara L
2017-11-15
Comparative studies of fish swimming have been limited by the lack of quantitative definitions of fish gaits. Traditionally, steady swimming gaits have been defined categorically by the fin or region of the body that is used as the main propulsor and named after major fish clades (e.g. carangiform, anguilliform, balistiform, labriform). This method of categorization is limited by the lack of explicit measurements, the inability to incorporate contributions of multiple propulsors and the inability to compare gaits across different categories. I propose an alternative framework for the definition and comparison of fish gaits based on the propulsive contribution of each structure (body and/or fin) being used as a propulsor relative to locomotor output, and demonstrate the effectiveness of this framework by comparing three species of neotropical cichlids with different body shapes. This approach is modular with respect to the number of propulsors considered, flexible with respect to the definition of the propulsive inputs and the locomotor output of interest, and designed explicitly to handle combinations of propulsors. Using this approach, gait can be defined as a trajectory through propulsive space, and gait transitions can be defined as discontinuities in the gait trajectory. By measuring and defining gait in this way, patterns of clustering corresponding to existing categorical definitions of gait may emerge, and gaits can be rigorously compared across categories. © 2017. Published by The Company of Biologists Ltd.
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Impact of selective breeding on European aquaculture
Janssen, K.; Chavanne, H.; Berentsen, P.; Komen, H.
2017-01-01
Objectives of this study were to determine the combined market share of breeding companies in aquaculture production in Europe, to describe the main characteristics of breeding companies and their programs, and to provide per species estimates on cumulative genetic gain in growth performance.
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Genetic characterization of Egyptian and Italian sheep breeds using mitochondrial DNA
Directory of Open Access Journals (Sweden)
Othman E. Othman
2015-06-01
The matrix of pairwise differences among breeds was used to perform a Principal Component Analysis (PCA. This analysis showed that the Italian breeds are clearly separated from the Egyptian breeds; moreover the Egyptian Barki breed is separated from Ossimi and Rahmani.
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Sustainable apple breedings needs sustainable marketing and management
Weber, M.
2008-01-01
Apple breeding programmes are currently in the middle of transition in terms of ownership and management. Until now most of them were funded by the public. Breeding took place by traditional methods since decades in a very sustainable way to develop better apple varieties. Today, increasing loss of national boundaries and globalisation, less interest by national bodies and institutions and rising cost levels for high tech breeding methods entire programmes are nowadays urged to...
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Simulated breeding with QU-GENE graphical user interface.
Hathorn, Adrian; Chapman, Scott; Dieters, Mark
2014-01-01
Comparing the efficiencies of breeding methods with field experiments is a costly, long-term process. QU-GENE is a highly flexible genetic and breeding simulation platform capable of simulating the performance of a range of different breeding strategies and for a continuum of genetic models ranging from simple to complex. In this chapter we describe some of the basic mechanics behind the QU-GENE user interface and give a simplified example of how it works.
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Characterization of recombination features and the genetic basis in multiple cattle breeds.
Shen, Botong; Jiang, Jicai; Seroussi, Eyal; Liu, George E; Ma, Li
2018-04-27
Crossover generated by meiotic recombination is a fundamental event that facilitates meiosis and sexual reproduction. Comparative studies have shown wide variation in recombination rate among species, but the characterization of recombination features between cattle breeds has not yet been performed. Cattle populations in North America count millions, and the dairy industry has genotyped millions of individuals with pedigree information that provide a unique opportunity to study breed-level variations in recombination. Based on large pedigrees of Jersey, Ayrshire and Brown Swiss cattle with genotype data, we identified over 3.4 million maternal and paternal crossover events from 161,309 three-generation families. We constructed six breed- and sex-specific genome-wide recombination maps using 58,982 autosomal SNPs for two sexes in the three dairy cattle breeds. A comparative analysis of the six recombination maps revealed similar global recombination patterns between cattle breeds but with significant differences between sexes. We confirmed that male recombination map is 10% longer than the female map in all three cattle breeds, consistent with previously reported results in Holstein cattle. When comparing recombination hotspot regions between cattle breeds, we found that 30% and 10% of the hotspots were shared between breeds in males and females, respectively, with each breed exhibiting some breed-specific hotspots. Finally, our multiple-breed GWAS found that SNPs in eight loci affected recombination rate and that the PRDM9 gene associated with hotspot usage in multiple cattle breeds, indicating a shared genetic basis for recombination across dairy cattle breeds. Collectively, our results generated breed- and sex-specific recombination maps for multiple cattle breeds, provided a comprehensive characterization and comparison of recombination patterns between breeds, and expanded our understanding of the breed-level variations in recombination features within an
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Will genomic selection be a practical method for plant breeding?
Nakaya, Akihiro; Isobe, Sachiko N
2012-11-01
Genomic selection or genome-wide selection (GS) has been highlighted as a new approach for marker-assisted selection (MAS) in recent years. GS is a form of MAS that selects favourable individuals based on genomic estimated breeding values. Previous studies have suggested the utility of GS, especially for capturing small-effect quantitative trait loci, but GS has not become a popular methodology in the field of plant breeding, possibly because there is insufficient information available on GS for practical use. In this review, GS is discussed from a practical breeding viewpoint. Statistical approaches employed in GS are briefly described, before the recent progress in GS studies is surveyed. GS practices in plant breeding are then reviewed before future prospects are discussed. Statistical concepts used in GS are discussed with genetic models and variance decomposition, heritability, breeding value and linear model. Recent progress in GS studies is reviewed with a focus on empirical studies. For the practice of GS in plant breeding, several specific points are discussed including linkage disequilibrium, feature of populations and genotyped markers and breeding scheme. Currently, GS is not perfect, but it is a potent, attractive and valuable approach for plant breeding. This method will be integrated into many practical breeding programmes in the near future with further advances and the maturing of its theory.
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Vlahos, Nikolaos; Vasilopoulos, Michael; Mente, Eleni; Hotos, George; Katselis, George; Vidalis, Kosmas
2015-09-01
In order to conserve and culture the cichlid fish Archocentrus nigrofasciatus, more information about its reproductive biology and its larval behavior and morphogenesis is necessary. Currently, temperatures ranging from 21 to 27 °C are used in ornamental aquaculture hatcheries. Lower temperatures are preferred to reduce the costs of water heating, and 23 °C is usually the selected temperature. However, there is limited information on culturing protocols for ornamental species and most of the information generated on this topic remains scarce. Thus, the present study examines the morphological development of Archocentrus nigrofasciatus during the yolk-sac period up to the age of 100 h post-hatching in relation to 2 temperature regimes used in ornamental aquaculture: a temperature of 27 °C (thermal optimum) and a decreased temperature of 23 °C (thermal tolerance). The results of this study suggest that the 27 °C temperature generates intense morphological changes in yolk-sac development in a shorter period. This has advantages as it reduces the time of yolk-sac larval development, and, thus, minimizes the transition phase to exogenous feeding and maximizes the efficiency at which yolk is converted into body tissues. The present paper provides necessary information to produce freshwater ornamental fish with better practices so as to increase larval survival and capitalize on time for growth. © 2015 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.
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Breeding implications resulting from classification of patellae luxation in dogs.
van Grevenhof, E M; Hazewinkel, H A W; Heuven, H C M
2016-08-01
Patellar luxation (PL) is one of the major hereditary orthopaedic abnormalities observed in a variety of dog breeds. When the patellae move sideways out of the trochlear groove, this is called PL. The PL score varies between dogs from normal to very severe. Reducing the prevalence of PL by breeding could prevent surgery, thereby improve welfare. Orthopaedic specialists differentiate between normal and loose patellae, where the patellae can be moved to the edge of the trochlear groove, considering scoring loose patellae as normal in the future. Loose patellae are considered acceptable for breeding so far by the breeding organization. The aim of this study was to analyse the genetic background of PL to decide on the importance of loose patellae when breeding for healthy dogs. Data are available from two dog breeds, that is Flat-coated Retrievers (n = 3808) and Kooiker dogs (n = 794), with a total of 4602 dogs. Results show that loose patellae indicate that dogs are genetically more susceptible to develop PL because family members of the dogs with loose patellae showed more severe PL. In addition, the estimated breeding values for dogs with loose patellae indicate that breeding values of dogs with loose patellae were worse than breeding values obtained for dogs with a normal score. Given these results, it is advised to orthopaedic specialists to continue to score loose patellae as a separate class and to dog breeders to minimize the use of dogs in breeding with a genetically higher susceptibility for PL. © 2015 Blackwell Verlag GmbH.
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International Nuclear Information System (INIS)
1996-01-01
In 1995, Nuclear Regulatory Authority of the Slovak Republic (NRA SR) ensured foreign cooperation particularly in the frame of the Slovak Republic is membership in the IAEA, as well as cooperation with the Nuclear Energy Agency of the Organization for Economic Cooperation and Development (OECD NEA), cooperation with European Union in the frame of PHARE programmes, and intergovernmental cooperation and cooperation among nuclear regulatory authorities. With respect to an international importance, prestige and a wide-scope possibilities of a technical assistance , either a direct one (expert assessments, technology supplies, work placement, scientific trips, training courses) or indirect one (participation at various conferences, seminars, technical committees, etc), the most important cooperation with the IAEA in Vienna. In 1994, the Slovak Republic, was elected to the Board Governors, the represent the group of Eastern European countries. The Slovak Government entrusted the NRA SR's Chairman with representing the Slovak Republic in the Board of Governors. Owing to a good name of Slovakia was elected to the one of two Vice-Chairmen of the Board of Governors at the 882-nd session on the Board. IAEA approved and developed 8 national projects for Slovakia in 1995. Generally, IAEA is contracting scientific contracts with research institutes, nuclear power plants and other organizations. Slovak organizations used these contracts as complementary funding of their tasks. In 1995, there were 12 scientific contracts in progress, or approved respectively. Other international activities of the NRA SR, international co-operations as well as foreign affairs are reported
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Filling the toolbox of precision breeding methods
Schaart, J.G.; Wiel, van de C.C.M.; Lotz, L.A.P.; Smulders, M.J.M.
2016-01-01
Plant breeding has
resulted in numerous
high-quality crop
varieties being
cultivated nowadays.
Breeding based on
crossing and selection
remains an important
and ongoing activity for
crop improvement, but
needs innovation to be
able to address -
Louwaars, N.P.; Dons, J.J.M.; Overwalle, van G.; Raven, H.; Arundel, A.; Eaton, D.; Nelis, A.
2009-01-01
Plant breeding serves an important public interest. Two intellectual property (IP) systems are relevant for the protection of innovations in this sector: plant breeder's rights and patent rights. Some exemptions play an important role in plant breeding, such as the 'breeder's exemption', which is
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Breeding for mechanised sesame production in Australia
International Nuclear Information System (INIS)
Beech, D.F.; Imrie, B.C.
2001-01-01
Introduction of sesame germplasm from Myanmar and Mexico was not satisfactory for successful development of the Australian sesame industry. Therefore, a national breeding programme was undertaken by CSIRO and the Northern Territory Department of Primary Industry and Fisheries (NTDPIF). The main traits considered for selection were latitudinal adaptation, temperature response, growth habit, determinacy, palatability, capsules per leaf axil, seed shattering and seed dormancy. The CSIRO breeding efforts started in 1989 with a hybridization programme using germplasm from Japan, Mexico, Myanmar, Rep. of Korea and Venezuela. This programme resulted in selection in the F 6 generation of branched types released under the names 'Beech's choice' and 'Aussie Gold'. The NTDPIF sesame breeding programme started in 1993 with hybridization of introductions. The Mexican cultivar 'Yori 77' was selected for release, and after several years of intraline selection the uniculm cultivar 'Edith' was released in 1996. Further breeding continues to improve seed retention and resistance to charcoal rot. (author)
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Unique cultural values of Madura cattle: is cross-breeding a threat?
Tri Satya Mastuti Widi, Tri; Udo, H.M.J.; Oldenbroek, J.K.; Budisatria, I.G.S.; Baliarti, E.; Zijpp, van der A.J.
2013-01-01
In Indonesia, cross-breeding local cattle with European beef breeds is widely promoted to stimulate beef production. This cross-breeding is threatening local breeds that have often different functions, including cultural roles. This study analysed the cultural values of Madura cattle and the effects
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SPRING BARLEY BREEDING FOR MALTING QUALITY
Directory of Open Access Journals (Sweden)
Alžbeta Žofajová
2010-05-01
Full Text Available The aim of this contribution is to illustrate the results of spring barley breeding for malting quality and point out an important position of variety in production of qualitative raw material for maltinq and beer industry as well as the system of evaluation the qualitative parameters of breeding materials and adaptation of barley breeding programms to the new requirements of malting and beer industry. As an example of the results obtained most recently description is made of the Ezer, Levan, Donaris, Sladar spring barley varieties with very good malting quality and effective resistance to powdery mildew. Cultivation of these varieties and malting barley production with reduced use of pesticidies is environmentally friedly alternative. doi:10.5219/50
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Breed differences of bull frozen-thawed semen.
Ntemka, A; Tsousis, G; Brozos, C; Kiossis, E; Boscos, C M; Tsakmakidis, I A
2016-12-01
The objective of this study was to investigate the quality of frozen-thawed semen from different bull breeds. Commercial frozen-thawed bull semen samples (26 per breed, 130 totally) of five breeds (Holstein [Η], Brown Swiss [BS], Limousin [L], Belgian Blue [BB], Blonde d' Aquitaine [BA]) were used. After thawing, each semen sample was subjected to thermal resistance test (TR) for 0.5 and 1 hr at 38°C and hypo-osmotic swelling test (HOST) for 1 hr at 150 mOsm at 37°C. Additionally, all samples were evaluated at times 0 hr (thawing), 0.5 hr (TR), 1 hr (TR) for kinetics by CASA [progressive, immotile, rapid, medium, slow moving spermatozoa, curvilinear velocity (VCL), average path velocity (VAP), straight line velocity (VSL), linearity (LIN), straightness (STR), beat cross-frequency (BCF), amplitude of lateral head displacement (ALH), wobble (WOB)]. Moreover, directly after thawing, all semen samples were evaluated for morphometry, morphology, viability and DNA fragmentation. Statistical analysis was conducted using a mixed model for repeated measures. The results showed (a) higher VCL after thawing in H, L breeds compared to BB and BA, (b) higher VAP after thawing in L compared to BB, BA, (c) higher values of progressive spermatozoa after TR in H, BS compared to BB, BA, (d) higher values of rapid spermatozoa after thawing and 0.5 hr of TR in H, BS, L compared to BB, BA, (e) lower viability in BA after thawing compared to H, BS, BB, (f) lower morphological abnormalities in H compared to L, BB, (g) higher head length in Η compared to BB. No significant differences were observed in the results from HOST and DNA fragmentation between breeds. In conclusion, quality characteristics of frozen-thawed bull semen are dependent on the breed. Frozen semen from BB and BA breeds should be handled more carefully after thawing, as it is more sensitive to stress. © 2016 Blackwell Verlag GmbH.
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Possibilities for marker-assisted selection in aquaculture breeding schemes
International Nuclear Information System (INIS)
Sonesson, A.K.
2007-01-01
FAO estimates that there are around 200 species in aquaculture. However, only a few species have ongoing selective breeding programmes. Marker-assisted selection (MAS) is not used in any aquaculture breeding scheme today. The aim of this chapter, therefore, is to review briefly the current status of aquaculture breeding schemes and to evaluate the possibilities for MAS of aquaculture species. Genetic marker maps have been published for some species in culture. The marker density of these maps is, in general, rather low and the maps are composed of many amplified fragment length polymorphism (AFLP) markers anchored to few microsatellites. Some quantitative trait loci (QTL) have been identified for economically important traits, but they are not yet mapped at a high density. Computer simulations of within-family MAS schemes show a very high increase in genetic gain compared with conventional family-based breeding schemes, mainly due to the large family sizes that are typical for aquaculture breeding schemes. The use of genetic markers to identify individuals and their implications for breeding schemes with control of inbreeding are discussed. (author)
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Breeding quinoa (Chenopodium quinoa Willd.)
DEFF Research Database (Denmark)
Zurita-Silva, Andrés; Fuentes, Francisco; Zamora, Pablo
2014-01-01
scale. In the Andes, quinoa has until recently been marginally grown by small-scale Andean farmers, leading to minor interest in the crop from urban consumers and the industry. Quinoa breeding programs were not initiated until the 1960s in the Andes, and elsewhere from the 1970s onwards. New molecular...... tools available for the existing quinoa breeding programs, which are critically examined in this review, will enable us to tackle the limitations of allotetraploidy and genetic specificities. The recent progress, together with the declaration of "The International Year of the Quinoa" by the Food...
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Genomic breeding value prediction:methods and procedures
Calus, M.P.L.
2010-01-01
Animal breeding faces one of the most significant changes of the past decades – the implementation of genomic selection. Genomic selection uses dense marker maps to predict the breeding value of animals with reported accuracies that are up to 0.31 higher than those of pedigree indexes, without the
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Yang, Nan; Moermond, Timothy C; Lloyd, Huw; Xu, Yu; Dou, Liang; Zhang, Kai; Yue, Bisong; Ran, Jianghong
2016-01-01
Our goal was to document effects of year-round supplemental feeding on breeding ecology of the Buff-throated Partridge, Tetraophasis szechenyii, within a Tibetan sacred site. We evaluated effects of supplemental feeding used as religious/cultural practices which could potentially aid conservation of endangered phasianids. We compared fed breeding groups to neighboring nonfed groups. Fed groups initiated first clutches significantly earlier than nonfed groups. Earlier laying groups within fed and nonfed groups showed significantly lower hatching rates than later groups; however, fed groups showed significantly higher hatching rates than nonfed groups laying in the same period. Earlier laying increased opportunities to renest. All six fed groups with clutch failures renested compared to only one of five nonfed groups with clutch failures. Fed female breeders showed significantly greater investment in their young with larger clutches and larger eggs, which likely increased survivability of early hatchlings. We observed no predation on birds at feeding sites and recorded only four cases of predation on incubating females, which showed no detectable difference between fed and nonfed groups. Ground-nesting birds typically face high risks of predation. Ten of the 48 groups nested in trees, which occurs in few phasianid species. Tree nests showed significantly higher hatching rates compared to ground nests; however, we found no significant difference in tree nesting between fed and nonfed groups. This partridge is one of four gallinaceous species with cooperative breeding. Breeding groups with helpers had significantly greater reproductive success than single pairs, and fed female breeders with helpers laid bigger eggs than single pairs. Comparing annual reproductive output per group, fed groups not only produced significantly more independent young (≥ 150 days post-hatching), their young hatched significantly earlier, which likely have greater reproductive value over
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International Nuclear Information System (INIS)
Broertjes, C.
1975-01-01
Mutation breeding in vegetatively propagated plants is of great potential value 1) to improve the leading results of cross-breeding by altering one or a few important characters, without the rest of the genotype, 2) to induce variability where none is existing or difficult to be introduced in highly developed species and 3) to induce variability in sterile crops or in apomicts. One of the main stumbling-blocks is the chimera formation following the irradiation of the multicellular apices in buds and the subsequent prolonged time and increased labour needed before a mutation can be detected, recovered and compared with the existing cultivars. This problem can be solved by producing plants, ultimately originating from one mutated cell, resulting in solid mutants. The in vivo adventitious bud technique, using detached leaves, has proven its value for mutation breeding. It has been demonstrated in several species that commercial results can be obtained in a relatively short time. Experiments are underway to study the factors which control the process of adventitious bud formation and to make more crops accessible to this method. So far, however, with little success. Many and increasingly more crops can be propagated clonally by in vitro methods, using plant parts (explants of leaves, flowers, flower stalk), callus or other plant material. In some cases it is expected that adventitious plantlets also will originate from one cell. In other cases it is to be investigated which method is of potential value for being used in a mutation breeding programme. In a cooperative project (C. Broertjes, S. Roest and Miss G.S. Bokelmann) it is under investigation which plant part (young flowerheads, flower stalks and leaves) is to be preferred in Chrysanthemum morifolium. Preliminary results will be presented at the meeting. (author)
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Tomotani, Barbara M.; Muijres, Florian T.; Koelman, Julia; Casagrande, Stefania; Visser, Marcel E.
2018-01-01
* Long-distance migrants are time-constrained as they need to incorporate many annual cycle stages within a year. Migratory passerines moult in the short interval between breeding and migration. To widen this interval, moult may start while still breeding, but this results in flying with moulting
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Mizumo Tomotani, Barbara; Muijres, F.T.; Koelman, Julia; Casagrande, Stefania; Visser, Marcel E.
2018-01-01
1.Long-distance migrants are time-constrained as they need to incorporate many annual cycle stages within a year. Migratory passerines moult in the short interval between breeding and migration. To widen this interval, moult may start while still breeding, but this results in flying with moulting
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Ion beam biotechnology and its application to maize breeding
International Nuclear Information System (INIS)
Yu Lixia; Li Wenjian; Dong Xicun; Zhou Libin; Ma Shuang
2008-01-01
Since the mid of 1980's, ion beam had been widely used in mutagenic breeding of various crops. Ion beam biotechnology had provided a new way for improving corn variety and creating new germplasm resources, and had promoted the development of maize breeding. The ion beam characteristics, the mutagenic mechanism and its application in maize breeding were described. (authors)
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Schofield, Pamela J.; Loftus, William F.; Kobza, Robert M.; Cook, Mark I.; Slone, Daniel H.
2010-01-01
The cold tolerance of two non-native cichlids (Hemichromis letourneuxi and Cichlasoma urophthalmus) that are established in south Florida was tested in the field and laboratory. In the laboratory, fishes were acclimated to two temperatures (24 and 28°C), and three salinities (0, 10, and 35 ppt). Two endpoints were identified: loss of equilibrium (11.5–13.7°C for C. urophthalmus; 10.8–12.5°C for H. letourneuxi), and death (9.5–11.1°C for C. urophthalmus; 9.1–13.3°C for H. letourneuxi). In the field, fishes were caged in several aquatic habitats during two winter cold snaps. Temperatures were lowest (4.0°C) in the shallow marsh, where no fish survived, and warmest in canals and solution-holes. Canals and ditches as shallow as 50 cm provided thermal refuges for these tropical fishes. Because of the effect on survival of different habitat types, simple predictions of ultimate geographic expansion by non-native fishes using latitude and thermal isoclines are insufficient for freshwater fishes.
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Cisgenesis strongly improves introgression breeding and induced translocation breeding of plants
Jacobsen, E.; Schouten, H.J.
2007-01-01
There are two ways for genetic improvement in classical plant breeding: crossing and mutation. Plant varieties can also be improved through genetic modification; however, the present GMO regulations are based on risk assessments with the transgenes coming from non-crossable species. Nowadays, DNA
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Genetic diversity in Egyptian and Italian goat breeds measured with microsatellite polymorphism.
Agha, S H; Pilla, F; Galal, S; Shaat, I; D'Andrea, M; Reale, S; Abdelsalam, A Z A; Li, M H
2008-06-01
Seven microsatellite markers were used to study genetic diversity of three Egyptian (Egyptian Baladi, Barki and Zaraibi) and two Italian (Maltese and Montefalcone) goat breeds. The microsatellites showed a high polymorphic information content (PIC) of more than 0.5 in most of the locus-breed combinations and indicated that the loci were useful in assessing within- and between-breed variability of domestic goat (Capra hircus). The expected heterozygosity of the breeds varied from 0.670 to 0.792. In the geographically wider distributed Egyptian Baladi breed there were indications for deviations from random breeding. Analysis of genetic distances and population structure grouped the three Egyptian goat breeds together, and separated them from the two Italian breeds. The studied Mediterranean breeds sampled from African and European populations seem to have differentiated from each other with only little genetic exchange between the geographically isolated populations.
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Plant Breeding and Genetics Newsletter, No. 31, July 2013
International Nuclear Information System (INIS)
2013-07-01
induction) and capacity built; technology packages are further tested and debugged in research networks (CRPs); and then the technology is transferred to our counterparts in Member States through Technical Cooperation projects. Two CRPs will close in 2013. You will find more information about CRP D2.40.12, ''Enhancing the Efficiency of Induced Mutagenesis through an Integrated Biotechnology Pipeline'', in this issue. This CRP proposed to address efficiency of mutation induction through the assembly, adaptation and interlacing of novel cellular and molecular biology techniques to achieve a seamless dove- tailing of validated processes into a modular pipeline: cellular and molecular biology techniques addressing the bottlenecks imposed by the need to generate large mutant populations rapidly in appropriate genetic backgrounds (homozygous for the mutation events, devoid of chimeras and in contemporary breeding materials). By scrutinizing target genes for desired changes, the need for field trials of large populations will be precluded. Milestones include the development of rapid techniques for dissolution of chimeras in vegetatively propagated banana; establishment of barley TILLING for targeting genes controlling drought; microspore mutagenesis for instant production of homozygous true breeding mutant lines; reduced representation next-generation sequencing approaches to screen mutant rice populations; and development and validation of low cost methods for mutant screening. Major milestones have been reached in CRP D2.40.23, ''Isolation and Characterization of Genes Involved in Mutagenesis of Crop Plants''. Genes encoding core proteins of the repair pathway in rice have been cloned and are being characterized. Whole genome scanning in soybean is under way for naturally mutated and selected genes. A chloroplast mutator gene and mutations caused by it have been identified in barley, and three putative DNA repair genes in pea are currently under study. Mutant populations of rice
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Organic plant breeding and propagation : concepts and strategies
Lammerts van Bueren, E.T.
2002-01-01
Key-words
: crop ideotype, genetic diversity, integrity of plants, intrinsic value, isophenic line mixture varieties, organic plant breeding, organic farming, organic propagation, participatory plant breeding, variety characteristics, -
Mutation breeding in diffrent types of pepper
International Nuclear Information System (INIS)
2010-01-01
This project was carried out under the collaboration of TAEK, SANAEM, and BATEM within 1999-2005 period. The aim of this project was to create new pepper varieties in Sera Demre 8 (green pepper) and ST59 (green pepper) cultivars which are important greenhouse cultivars by using mutation breeding methods. The Effective Mutagen Dose (ED50) was calculated by linear regression analyses. According to results, 166 Gy dose was found as ED50. At the end of the breeding cycle 14 new mutant lines were obtained from mutant population. These mutant lines are still using as genitor for F1 hybrid pepper breeding programs
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Domestication and Breeding of Jatropha curcas L.
Montes, Juan M; Melchinger, Albrecht E
2016-12-01
Jatropha curcas L. (jatropha) has a high, untapped potential to contribute towards sustainable production of food and bioenergy, rehabilitation of degraded land, and reduction of atmospheric carbon dioxide. Tremendous progress in jatropha domestication and breeding has been achieved during the past decade. This review: (i) summarizes current knowledge about the domestication and breeding of jatropha; (ii) identifies and prioritizes areas for further research; and (iii) proposes strategies to exploit the full genetic potential of this plant species. Altogether, the outlook is promising for accelerating the domestication of jatropha by applying modern scientific methods and novel technologies developed in plant breeding. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Progress in a Crambe cross breeding programme
Mastebroek, H.D.; Lange, W.
1997-01-01
Crambe (Crambe abyssinica Hochst. ex Fries) is an annual cruciferous oilseed crop with a high content of erucic acid (55-60%) in the seed oil. Since 1990, a breeding programme in crambe has been carried out at the DLO-Centre for Plant Breeding and Reproduction Research. Three accessions, two early
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International Nuclear Information System (INIS)
Prieto, F.E.
1984-01-01
It looks doubtless that the need for an international cooperation to solve the worldwide energy problems is already a concern of individuals, institutions, and governments. This is an improvement. But there is something lacking. The author refers to the Atoms for Peace speech, the origin of the IAEA and of the subsequent spreading of the nuclear option. He also refers back to the call made by the Mexican government for a worldwide energy cooperation. He stresses the need for governments to cooperate, so that this international cooperation on energy can be put into operation for the benefit of mankind
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Population dynamics of mallards breeding in eastern Washington
Dugger, Bruce D.; Coluccy, John M.; Dugger, Katie M.; Fox, Trevor T.; Kraege, Donald K.; Petrie, Mark J.
2016-01-01
Variation in regional population trends for mallards breeding in the western United States indicates that additional research into factors that influence demographics could contribute to management and understanding the population demographics of mallards across North America. We estimated breeding incidence and adult female, nest, and brood survival in eastern Washington in 2006 and 2007 by monitoring female mallards with radio telemetry and tested how those parameters were influenced by study year (2006 vs. 2007), landscape type (agricultural vs. natural), and age (second year [SY] vs. after second year [ASY]). We also investigated the effects of female body condition and capture date on breeding incidence, and nest initiation date and hatch date on nest and brood survival, respectively. We included population parameters in a stage-based demographic model and conducted a perturbation analysis to identify which vital rates were most influential on population growth rate (λ). Adult female survival was best modeled with a constant weekly survival rate (0.994, SE = 0.003). Breeding incidence differed between years and was higher for birds in better body condition. Nest survival was higher for ASY females (0.276, SE = 0.118) than SY females (0.066, SE = 0.052), and higher on publicly managed lands (0.383, SE = 0.212) than agricultural (0.114, SE = 0.058) landscapes. Brood survival was best modeled with a constant rate for the 7-week monitoring period (0.50, SE = 0.155). The single variable having the greatest influence on λ was non-breeding season survival, but the combination of parameters from the breeding grounds explained a greater percent of the variance in λ. Mallard population growth rate was most sensitive to changes in non-breeding survival, nest success, brood survival, and breeding incidence. Future management decisions should focus on activities that improve these vital rates if managers want to increase the production of
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Importance of determining the climatic domains of sheep breeds.
Petit, D; Boujenane, I
2018-07-01
The main purpose of the study was to compare the capacity of the major sheep breeds in Morocco to cope with climate changes through the ranges of several climate parameters in which they can be found. We first delimitated the climatic 'domains' of each breed by constructing a database including altitude and climatic parameters (minima mean of the coldest month, maxima mean of the hottest month, annual rainfall, pluviothermic coefficient of Emberger Q 2, annual minima mean and annual maxima mean) on a 30-year period using the representative stations of each breed distribution. The overlap between each breed combination was quantified through a canonical analysis that extracted the most discriminant parameters. The variance analysis of each climatic parameter evidenced two breeds remarkable by their tolerance. The first one is the Timahdite, mainly settled in areas over 1100 m, which can tolerate the greatest variations in annual rainfall and pluviothermic coefficient. In spite of this feature, this breed is endangered owing to the decreasing quality of pastures. The second one is the D'man which apparently can support high variations in extreme temperatures. In fact, this breed is not well adapted to pastures and requires a special microclimate offered by oases. The information reported in this study will be the basis for the establishment of characterization and selection strategies for Moroccan sheep.
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Büchner, Vera Antonia; Hinz, Vera; Schreyögg, Jonas
2015-01-01
Several public policy initiatives, particularly those involving managed care, aim to enhance cooperation between partners in the health care sector because it is expected that such cooperation will reduce costs and generate additional revenue. However, empirical evidence regarding the effects of cooperation on hospital performance is scarce, particularly with respect to creating a comprehensive measure of cooperation behavior. The aim of this study is to investigate the impact of hospital cooperation behavior on organizational performance. We differentiate between horizontal and vertical cooperation using two alternative measures-cooperation depth and cooperation breadth-and include the interaction effects between both cooperation directions. Data are derived from a survey of German hospitals and combined with objective performance information from annual financial statements. Generalized linear regression models are used. The study findings provide insight into the nature of hospitals' cooperation behavior. In particular, we show that there are negative synergies between horizontal administrative cooperation behavior and vertical cooperation behavior. Whereas the depth and breadth of horizontal administrative cooperation positively affect financial performance (when there is no vertical cooperation), vertical cooperation positively affects financial performance (when there is no horizontal administrative cooperation) only when cooperation is broad (rather than deep). Horizontal cooperation is generally more effective than vertical cooperation at improving financial performance. Hospital managers should consider the negative interaction effect when making decisions about whether to recommend a cooperative relationship in a horizontal or vertical direction. In addition, managers should be aware of the limited financial benefit of cooperation behavior.
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Influence of cross-breeding of native breed sows of Zlotnicka ...
African Journals Online (AJOL)
ZUZA
2011-11-16
Nov 16, 2011 ... 1The Poznan University of Life Sciences, Department of Pig Breeding and Production, ul. Wolynska 33,. 60-637 ... ZS x D had significantly higher share of meat cuts in comparison with purebred fatteners ZS and crossbred fatteners ZS x (ZS x D). ... Proximate composition of diets. Item. Diet. Starter. Grower.
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Mutation breeding in vegetable crops
Energy Technology Data Exchange (ETDEWEB)
Yamaguchi, Takashi
1984-03-01
Vegetables breed by seeds and vegetative organs. In main vegetables, the differentiation of clopping types, the adoption of monoculture and year-round production and shipment are carried out, adapting to various socio-economic and cultivation conditions. Protected agriculture has advanced mainly for fruit vegetables, and the seeds for sale have become almost hybrid varieties. Reflecting this situation, the demand for breeding is diversified and characteristic. The present status of mutation breeding of vegetables is not yet well under way, but reports of about 40 raised varieties have been published in the world. The characters introduced by induced mutation and irradiation are compact form, harvesting aptitude, the forms and properties of stems and leaves, anti-lodging property, the size, form and uniformity of fruits, male sterility and so on. The radiation sources used were mostly gamma ray or X-ray, but sometimes, combined irradiation was used. Results obtained in Japan include: burdocks as an example to gamma ray irradiation of seeds; tomatoes as an example of inducing compound resistance against disease injury; and lettuce as an example of internal beta irradiation. (Kako, I.).
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Resistance Genes in Global Crop Breeding Networks.
Garrett, K A; Andersen, K F; Asche, F; Bowden, R L; Forbes, G A; Kulakow, P A; Zhou, B
2017-10-01
Resistance genes are a major tool for managing crop diseases. The networks of crop breeders who exchange resistance genes and deploy them in varieties help to determine the global landscape of resistance and epidemics, an important system for maintaining food security. These networks function as a complex adaptive system, with associated strengths and vulnerabilities, and implications for policies to support resistance gene deployment strategies. Extensions of epidemic network analysis can be used to evaluate the multilayer agricultural networks that support and influence crop breeding networks. Here, we evaluate the general structure of crop breeding networks for cassava, potato, rice, and wheat. All four are clustered due to phytosanitary and intellectual property regulations, and linked through CGIAR hubs. Cassava networks primarily include public breeding groups, whereas others are more mixed. These systems must adapt to global change in climate and land use, the emergence of new diseases, and disruptive breeding technologies. Research priorities to support policy include how best to maintain both diversity and redundancy in the roles played by individual crop breeding groups (public versus private and global versus local), and how best to manage connectivity to optimize resistance gene deployment while avoiding risks to the useful life of resistance genes. [Formula: see text] Copyright © 2017 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .
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Choosing the cooperative option
Energy Technology Data Exchange (ETDEWEB)
English, G. (National Rural Electric Cooperative Association (United States))
1999-06-01
Cooperatives do not ask to be exempted from the law. They do ask that laws and regulations be designed to allow them to meet the needs of their consumer-owners in accordance with cooperative principles, at a time that the marginal consumers being abandoned by for-profit utilities may be ready to gravitate toward cooperatives. The cooperative principles are worth reviewing because they explain the focus on the consumer and the cooperative concept of service: cooperatives are voluntary organizations, open to all persons able to use their services and willing to accept the responsibilities of membership; cooperatives are democratic organizations controlled by their members, who actively participate in setting policies and making decisions, the elected representatives are accountable to the membership; members contribute equitably to, and democratically control, the capital of their cooperative; cooperatives are autonomous, self-help organizations controlled by their members, if they enter into agreements with other organizations, including governments, they do so on terms that ensure democratic control by their members and maintain their cooperative autonomy; cooperatives provide education and training for their members, elected representatives, managers, and employees so they can contribute effectively to the development of their cooperatives, they inform the general public, particularly young people and opinion leaders, about the nature and benefits of cooperation; cooperatives serve their members most effectively and strength the cooperative movement by working together through local, national, regional, and international structures; and while focusing on member needs, cooperatives work for the sustainable development of their communities through policies accepted by their members.
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USE OF GROWTH CHAMBERS FOR CABBAGE BREEDING
Directory of Open Access Journals (Sweden)
L. L. Bondareva
2014-01-01
Full Text Available Use of the growth chambers for cabbage breeding allows the reducing of certain stages of the breeding process and the growing biennial varieties of cabbage in a one-year cycle. In these growth chambers, the nutritional conditions, temperature, and lighting of plants are under control; the open pollination is eliminated.
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International Nuclear Information System (INIS)
1998-01-01
In this part the are reviewed: Co-operation with IAEA; Participation of the Slovakia on the 41 st session of the General Conference; The comprehensive Nuclear-Test-Ban Treaty Organization; Co-operation with the Organization for Economic Co-operation and Development; co-operation with the European Commission; Fulfillment of obligations resulting from the international contracting documents
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Parente, Thiago E M; De-Oliveira, Ana C A X; Paumgartten, Francisco J R
2008-03-01
The induction of cytochrome P4501A-mediated activity (e.g. ethoxyresorufin-O-deethylation, EROD) has been used as a biomarker for monitoring fish exposure to AhR-receptor ligands such as polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and polychlorinated dibenzo-dioxins/furans (PCDD/Fs). In this study we found that hepatic EROD is induced in fish ("Nile tilapia", Oreochromis niloticus and "acará", Geophagus brasiliensis) from the Guandu River (7-17-fold) and Jacarepaguá Lake (7-fold), Rio de Janeiro, Brazil. Since both cichlid fish are consumed by the local population and the Guandu River is the main source of the drinking water supply for the greater Rio de Janeiro metropolitan area, pollution by cytochrome P4501A-inducing chemicals is a cause for concern and should be further investigated in sediments, water and biota. We additionally showed that EROD activity in the fish liver post-mitochondrial supernatant-simpler, cheaper and less time consuming to prepare than the microsomal fraction-is sufficiently sensitive for monitoring purposes.
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Genetic relationships between six eastern Pyrenean sheep breeds assessed using microsatellites
Directory of Open Access Journals (Sweden)
Ainhoa Ferrando
2014-11-01
Full Text Available The knowledge of the genetic composition and relationships among livestock breeds is a necessary step for the implementation of management and conservation plans. This study aims to characterise the genetic diversity and relationships among six sheep breeds of meat aptitude that are spread through the eastern Pyrenees: Tarasconnaise, Castillonnaise and Rouge du Roussillon from France, and Aranesa, Xisqueta and Ripollesa from Spain. All but Tarasconnaise are catalogued as endangered. These breeds do not share the same ancestral origin but commercial trades and gene flow between herds are known to have occurred for centuries. Additionally, two outgroup breeds were included: the Guirra, from a different geographical location, and the Lacaune, a highly selected breed of dairy aptitude. A total of 410 individuals were typed using a panel of 12 microsatellite markers. Statistical, phylogenetic and Bayesian analyses showed that eastern Pyrenean breeds retained high levels of genetic diversity and low, but significant, levels of genetic differentiation (FST = 4.1%. While outgroups were clearly differentiated from other breeds, Pyrenean breeds tended to form two clusters. The first encompassed Tarasconnaise and Aranesa, which probably descend from a common meta-population. The second tended to group the other four breeds. However, none reached high mean Q-values of membership to a discrete cluster. This is consistent with the recent past gene flow between breeds, despite different ancestral genetic origins. The genetic characterisation carried out of the eastern Pyrenean sheep populations provides useful information to support decision making on their conservation and focusing efforts and resources to more singular breeds.
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MORE ON THE APPROVAL OF ANTONINSKO-ZOZULENETSKIY CARPS OF UKRAINIAN BREEDS
Directory of Open Access Journals (Sweden)
O. Oleksiyenko
2015-12-01
Full Text Available Purpose. To perform an analysis the fish breeding, biological, productive, exterior indicators of Antoninsko-Zozulenetskiy carps of Ukrainian scaly and Ukrainian framed breeds, their genetic characteristics as well as to provide the methods of the creation of these carps as a selective achievement. Methodology. The works were carried out in accordance with conventional techniques in fish farming and breeding. Carp breeding was conducted by the method of mass continuously improving selection of fish the aim of which is that a complex of fish breeding and management activities create conditions contributing to the development of productive qualities in the selected carp, while selection and breeding activities form and reproduce the leading pedigree group of the stock. Findings. In the conditions of the development of fisheries industry, especially important are the problems of selection and breeding works aimed at improving the biological and economic features of fish farming objects by improving the existing and developing new breeds, inbreeding, zonal types, lines, etc., creating a progressive heterotic structure of breeds and forming highly productive pedigree stocks of fish breeding objects. The main object of commercial fish farming in Ukraine, as in many countries, is carp, so his selection is given much attention. The starting material for producing the Antoninsko-Zozulenetskiy Ukrainian scaly and Ukrainian framed breeds was carp population of Antoninskiy State fish hatchery (Khmelnytsky region, which was a cross between native carp with mirror Galician carp. The principal method of carp breeding was a massive, continuously improving selection with high intensity among younger age groups. An importance during the selection was given to the growth rate of the fish, their exterior and constitutional "strength." For the brood, individuals with the highest body weight, scaly cover of which corresponded to accepted standards, beautiful high
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Aleksić, S.; Fang, Sun; Di, Liu; Petrović, M.M.; Pantelić, V.; Stanišić, N.; Ostojić-Andrić, D.; Petričević, M.; Nikšić, D.; Delić, N.
2013-01-01
This paper presents the results of crossing Domestic Spotted breed with beef cattle breeds in the People's Republic of China and the Republic of Serbia. China is a big country of beef production and consumption. In 2012, beef production in China was 5,540,000 tons, which accounted for 9.7% of the global beef production, ranking the third in the world. The main sources of China’s beef are from crossbreeding cattle (native breed crossbred with foreign beef ca...
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Marker-assisted selection in fish and shellfish breeding schemes
International Nuclear Information System (INIS)
Martinez, V.
2007-01-01
The main goals of breeding programmes for fish and shellfish are to increase the profitability and sustainability of aquaculture. Traditionally, these have been carried out successfully using pedigree information by selecting individuals based on breeding values predicted for traits measured on candidates using an 'animal model'. This methodology assumes that phenotypes are explained by a large number of genes with small effects and random environmental deviations. However, information on individual genes with medium or large effects cannot be used in this manner. In selective breeding programmes using pedigree information, molecular markers have been used primarily for parentage assignment when tagging individual fish is difficult and to avoid causing common environmental effects from rearing families in separate tanks. The use of these techniques in such conventional breeding programmes is discussed in detail. Exploiting the great biological diversity of many fish and shellfish species, different experimental designs may use either chromosomal manipulations or large family sizes to increase the likelihood of finding the loci affecting quantitative traits, the so-called QTL, by screening the segregation of molecular markers. Using information on identified loci in breeding schemes in aquaculture is expected to be cost-effective compared with traditional breeding methods only when the accuracy of predicting breeding values is rather low, e.g. for traits with low heritability such as disease resistance or carcass quality. One of the problems facing aquaculture is that some of the resources required to locate QTL accurately, such as dense linkage maps, are not yet available for the many species. Recently, however, information from expressed sequence tag (EST) databases has been used for developing molecular markers such as microsatellites and single nucleotide polymorphisms (SNPs). Marker-assisted selection (MAS) or genome-wide marker-assisted selection (G-MAS) using
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Enhancing genetic gain in the era of molecular breeding.
Xu, Yunbi; Li, Ping; Zou, Cheng; Lu, Yanli; Xie, Chuanxiao; Zhang, Xuecai; Prasanna, Boddupalli M; Olsen, Michael S
2017-05-17
As one of the important concepts in conventional quantitative genetics and breeding, genetic gain can be defined as the amount of increase in performance that is achieved annually through artificial selection. To develop pro ducts that meet the increasing demand of mankind, especially for food and feed, in addition to various industrial uses, breeders are challenged to enhance the potential of genetic gain continuously, at ever higher rates, while they close the gaps that remain between the yield potential in breeders' demonstration trials and the actual yield in farmers' fields. Factors affecting genetic gain include genetic variation available in breeding materials, heritability for traits of interest, selection intensity, and the time required to complete a breeding cycle. Genetic gain can be improved through enhancing the potential and closing the gaps, which has been evolving and complemented with modern breeding techniques and platforms, mainly driven by molecular and genomic tools, combined with improved agronomic practice. Several key strategies are reviewed in this article. Favorable genetic variation can be unlocked and created through molecular and genomic approaches including mutation, gene mapping and discovery, and transgene and genome editing. Estimation of heritability can be improved by refining field experiments through well-controlled and precisely assayed environmental factors or envirotyping, particularly for understanding and controlling spatial heterogeneity at the field level. Selection intensity can be significantly heightened through improvements in the scale and precision of genotyping and phenotyping. The breeding cycle time can be shortened by accelerating breeding procedures through integrated breeding approaches such as marker-assisted selection and doubled haploid development. All the strategies can be integrated with other widely used conventional approaches in breeding programs to enhance genetic gain. More transdisciplinary
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Mirzaei, A; Mohebbi-Fani, M; Omidi, A; Boostani, A; Nazifi, S; Mahmoodian-Fard, H R; Chahardahcherik, M
2017-09-15
The combination of ram effect with two injections of PGF 2α 10-days apart and the same protocol plus an additional injection of GnRH prior to the first injection of PGF 2α were examined in Karakul ewes during breeding and non-breeding seasons, respectively. Plasma progesterone (P 4 ) concentrations (to detect the presence of active corpus luteum), twin lambing, litter size and synchronization of lambing were evaluated. In each study 70 ewes (2-4 years old) were divided to a treatment (n = 40) and a control (n = 30) group. During the breeding season, on days -10 and 0 before ram release, the treatment group was injected intramuscularly with PGF 2α (D-Cloprostenol; 0.15 mg). During the non-breeding season, on day -15 before ram release the treatment group was injected with GnRH (buserelin; 4.2 μg) intramuscularly followed by two injections of PGF 2α on days -10 and 0. In both studies, the rams were released into the ewe flock after the second prostaglandin injection (day 0). Blood samples of ewes were collected on days -10, 0, 20 and 70 of the study in breeding season and on days -15, -10, 0, 20 and 70 during non-breeding season. The treatment group had higher P 4 concentrations compared to the control ewes on day 0 in the breeding season (5.80 ± 0.61 vs. 5.0 ± 0.93 ng/mL) and day -10 in the non-breeding season (3.50 ± 0.33 vs. 2.70 ± 0.35 ng/mL) though the differences were not significant (P > 0.05). Based on plasma P 4 concentrations (>1 ng/mL) on day 70, in the breeding season all control ewes (100%) and 91.9% of the treatment ewes were detected to have active corpus luteum (P = 0.09). An almost inverse result (90% vs. 97.5%; P = 0.2) was detected in the non-breeding season. The lambing rate was higher (P = 0.03) in the treatment group compared to the control ewes during the non-breeding season (90% vs. 70%), but tended to be lower (P = 0.07) in the breeding season (73% vs. 90%). Twin lambing rate was higher in the
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California Natural Resource Agency — This data set provides access to information gathered on annual breeding bird surveys in California using a map layer developed by the Department. This data layer...
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Lergetporer, Philipp; Angerer, Silvia; Glätzle-Rützler, Daniela; Sutter, Matthias
2014-05-13
The human ability to establish cooperation, even in large groups of genetically unrelated strangers, depends upon the enforcement of cooperation norms. Third-party punishment is one important factor to explain high levels of cooperation among humans, although it is still somewhat disputed whether other animal species also use this mechanism for promoting cooperation. We study the effectiveness of third-party punishment to increase children's cooperative behavior in a large-scale cooperation game. Based on an experiment with 1,120 children, aged 7 to 11 y, we find that the threat of third-party punishment more than doubles cooperation rates, despite the fact that children are rarely willing to execute costly punishment. We can show that the higher cooperation levels with third-party punishment are driven by two components. First, cooperation is a rational (expected payoff-maximizing) response to incorrect beliefs about the punishment behavior of third parties. Second, cooperation is a conditionally cooperative reaction to correct beliefs that third party punishment will increase a partner's level of cooperation.
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Genomic Characterisation of the Indigenous Irish Kerry Cattle Breed
Browett, Sam; McHugo, Gillian; Richardson, Ian W.; Magee, David A.; Park, Stephen D. E.; Fahey, Alan G.; Kearney, John F.; Correia, Carolina N.; Randhawa, Imtiaz A. S.; MacHugh, David E.
2018-01-01
Kerry cattle are an endangered landrace heritage breed of cultural importance to Ireland. In the present study we have used genome-wide SNP array data to evaluate genomic diversity within the Kerry population and between Kerry cattle and other European breeds. Patterns of genetic differentiation and gene flow among breeds using phylogenetic trees with ancestry graphs highlighted historical gene flow from the British Shorthorn breed into the ancestral population of modern Kerry cattle. Principal component analysis (PCA) and genetic clustering emphasised the genetic distinctiveness of Kerry cattle relative to comparator British and European cattle breeds. Modelling of genetic effective population size (Ne) revealed a demographic trend of diminishing Ne over time and that recent estimated Ne values for the Kerry breed may be less than the threshold for sustainable genetic conservation. In addition, analysis of genome-wide autozygosity (FROH) showed that genomic inbreeding has increased significantly during the 20 years between 1992 and 2012. Finally, signatures of selection revealed genomic regions subject to natural and artificial selection as Kerry cattle adapted to the climate, physical geography and agro-ecology of southwest Ireland. PMID:29520297
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Genomic Characterisation of the Indigenous Irish Kerry Cattle Breed
Directory of Open Access Journals (Sweden)
Sam Browett
2018-02-01
Full Text Available Kerry cattle are an endangered landrace heritage breed of cultural importance to Ireland. In the present study we have used genome-wide SNP array data to evaluate genomic diversity within the Kerry population and between Kerry cattle and other European breeds. Patterns of genetic differentiation and gene flow among breeds using phylogenetic trees with ancestry graphs highlighted historical gene flow from the British Shorthorn breed into the ancestral population of modern Kerry cattle. Principal component analysis (PCA and genetic clustering emphasised the genetic distinctiveness of Kerry cattle relative to comparator British and European cattle breeds. Modelling of genetic effective population size (Ne revealed a demographic trend of diminishing Ne over time and that recent estimated Ne values for the Kerry breed may be less than the threshold for sustainable genetic conservation. In addition, analysis of genome-wide autozygosity (FROH showed that genomic inbreeding has increased significantly during the 20 years between 1992 and 2012. Finally, signatures of selection revealed genomic regions subject to natural and artificial selection as Kerry cattle adapted to the climate, physical geography and agro-ecology of southwest Ireland.
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Evidence of selection signatures that shape the Persian cat breed.
Bertolini, Francesca; Gandolfi, Barbara; Kim, Eui Soo; Haase, Bianca; Lyons, Leslie A; Rothschild, Max F
2016-04-01
The Persian cat is mainly characterized by an extremely brachycephalic face as part of the standard body conformation. Despite the popularity, world-wide distribution, and economic importance of the Persian cat as a fancy breed, little is known about the genetics of their hallmark morphology, brachycephaly. Over 800 cats from different breeds including Persian, non-Persian breeds (Abyssinian, Cornish Rex, Bengal, La Perm, Norwegian Forest, Maine Coon, Manx, Oriental, and Siamese), and Persian-derived breeds (British Shorthair, Scottish Fold, Selkirk Rex) were genotyped with the Illumina 63 K feline DNA array. The experimental strategy was composed of three main steps: (i) the Persian dataset was screened for runs of homozygosity to find and select highly homozygous regions; (ii) selected Persian homozygous regions were evaluated for the difference of homozygosity between Persians and those considered non-Persian breeds, and, (iii) the Persian homozygous regions most divergent from the non-Persian breeds were investigated by haplotype analysis in the Persian-derived breeds. Four regions with high homozygosity (H > 0.7) were detected, each with an average length of 1 Mb. Three regions can be considered unique to the Persian breed, with a less conservative haplotype pattern in the Persian-derived breeds. Moreover, two genes, CHL1 and CNTN6 known to determine face shape modification in humans, reside in one of the identified regions and therefore are positional candidates for the brachycephalic face in Persians. In total, the homozygous regions contained several neuronal genes that could be involved in the Persian cat behavior and can provide new insights into cat domestication.
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Changes in sunflower breeding over the last fifty years
Directory of Open Access Journals (Sweden)
Vear Felicity
2016-03-01
Full Text Available This article discusses changes in sunflower breeding objectives since the introduction of hybrid varieties 50 years ago. After a reminder of the importance of some early programmes, Canadian in particular, the present situation for each breeding objective is compared with those encountered earlier. Breeding for yield has changed from maximum possible yield under intensive agriculture to yield with resistance to abiotic stresses, moderate droughts and shallow soils in particular, helped by collaboration with agronomists to produce crop models. Breeding for oil has changed from quantity to quality and the value of seed meal is again becoming economically important. Necessary disease resistances vary with agronomic practises and selection pressure on pathogens according to varietal genetics. The possibilities of new types of sunflower are also discussed. Advances in genomics will change breeding procedures, but with rapidly changing molecular techniques, international collaboration is particularly important.
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breeding Red-and-yellow Barbets Trachyphonus erythrocephalus
African Journals Online (AJOL)
(Table 1), but it was not possible to ascertain whether it was always the exact same pair breeding. Table 1. Breeding activity of Red-and-yellow Barbets from a single nest in south- eastern Sudan in 2005. Date. Brood No. Nesting activity. Fledging date. No. of Fledglings. Observed post-fledging. 11 Feb. 1 feeding young.
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Effects of spring conditions on breeding propensity of Greater Snow Goose females
Directory of Open Access Journals (Sweden)
Reed, E. T.
2004-06-01
Full Text Available Breeding propensity, defined as the probability that a sexually mature adult will breed in a given year, is an important determinant of annual productivity. It is also one of the least known demographic parameters in vertebrates. We studied the relationship between breeding propensity and conditions on spring staging areas (a spring conservation hunt and the breeding grounds (spring snow cover in Greater Snow Geese (Chen caerulescens atlantica, a long distance migrant that breeds in the High Arctic. We combined information from mark–recapture, telemetry, and nest survey data to estimate breeding propensity over a 7– year period. True temporal variation in breeding propensity was considerable (mean: 0.574 [95% CI considering only process variation: 0.13 to 1.0]. Spring snow cover was negatively related to breeding propensity (bsnow=-2,05 ± 0,96 SE and tended to be reduced in years with a spring hunt (b = -0,78 ± 0,35. Nest densities on the breeding colony and fall ratios of young:adults were good indices of annual variation in breeding propensity, with nest densities being slightly more precise. These results suggest that conditions encountered during the pre-breeding period can have a significant impact on productivity of Arctic-nesting birds
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Distal antebrachial fractures in toy-breed dogs
International Nuclear Information System (INIS)
Muir, P.
1997-01-01
Antebrachial fractures account for approximately 17% of all canine fractures, with motor vehicle trauma cited as one of the primary causes. However, antebrachial fractures in toy-breed dogs are often sustained after apparently minimal trauma, such as jumping or falling, and are usually distal. The cause of antebrachial fractures in toy breeds is not well understood. Complications after treatment of distal antebrachial fractures in toy-breed dogs, including delayed union, nonunion, and malunion, are common and are potentially serious because they may necessitate limb amputation. This article reports on distal antebrachial fractures in 26 toy-breed dogs that wee presented to the University of California, Davis, Veterinary Medical Teaching Hospital from April 1987 to March 1996. The author found that (1) these fractures typically occur in growing or adolescent dogs; (2) the presence of complications of union is typically associated with prior treatment using intramedullary pinning or external coaptation; and (3) successful healing of this type of fracture is obtained via rigid stabilization with bone plating in combination with cancellous bone autograft
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Parasitocenoses in productional rodent breeds in Czech Republic
Directory of Open Access Journals (Sweden)
Marie Borkovcová
2009-01-01
Full Text Available Aim of this work was to monitor the occurrence of most common parasites of rodents in 13 commercial and hobby breeds. Most often detected protozoans belonged to genera Giardia, Eimeria and Cryptosporidium, tapeworms Hymenolepis nana and H. diminuta, nematods Syphacia obvelata and Aspiculuris tetraptera and mites Ornithonyssus bacoti, Laelaps hilaris and Notoedres muris. Diseases broke out mainly during summer months. In animals with clinical signs of illnesses there was an expectation of parasite presence, and most of them were nematods – 80%, tapeworms – 45.2%, protozoans – 41.1% and ectoparasites – 22%. Samples of animals without clinical signs of illnesses contained nematods – 16%, tapeworms – 11%, coccidians – 6% and ectoparasites – 0%. Besides evaluation of all samples, breeding conditions were evaluated as well. Consequently plan was made to remove the causes of parasitoses for each monitored breed. Most dangerous parasites were coccidians of the genus Cryptosporidium, which caused high mortality of the young animals. In Czech Republic high percent of breeds are contaminated with parasites, however, there is little experience in how to deal with these illnesses. Results are weak and low-quality breeds, especially of mice and common rats. Important protection is buying animals from well-known and verified breed with no signs of illness and also regular control of excrement samples.
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Mutation breeding in South Africa 2003–2004
Energy Technology Data Exchange (ETDEWEB)
Vos, J. E.; Du Preez, R. J.; Froneman, I.; Hannweg, K.; Husselman, J.; Rheeder, S. [Agricultural Research Council-Institute for Tropical and Subtropical Crops, Nelspruit (South Africa)
2009-05-15
Four commercial citrus cultivars have been produced from conventional citrus mutation programme in South Africa. Three hundred and fifty citrus mutant lines obtained from sectoral chimeras using in vitro techniques were included in the citrus evaluation programme and useful mutations of particularly difficult-to-breed cultivars is continuing. Gamma irradiation response curves (Co{sup 60}) as well as the LD50 levels were determined for Citrus, Litchi, Guava, Cherimoya, Pitanga, Jaboticaba and Carambola. Grafting and propagation techniques for all species, and in particular, those where no information exists, were established. Citrus, Litchi, Guava, Cherimoya, Pitanga, Jaboticaba and Carambola are all characterised by having long juvenile phases making conventional breeding programmes slow and costly. Mutation breeding is being used in an attempt to overcome this problem and produce material which can be used in the screening of advantageous genes in subsequent breeding programmes. (author)
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R and D activities on radiation induced mutation breeding
International Nuclear Information System (INIS)
Lapade, A.G.; Asencion, A.B.; Santos, I.S.; Grafia, A.O.; Veluz, AM.S.; Barrida, A.C.; Marbella, L.J.
1996-01-01
This paper summarizes the accomplishments, prospects and future plans of mutation breeding for crop improvement at the Philippine Nuclear Research Institute (PNRI). Mutation induction has become a proven way creating variation within a crop variety and inducing desired attributes that cannot be found in nature or have been lost during evolution. Several improved varieties with desirable traits were successfully developed through induced mutation breeding at our research institute. In rice, mutation breeding has resulted in the development of new varieties: (1) PARC 2, (2) Milagrosa mutant, (3) Bengawan mutant and (4) Azmil mutant. Mutation breeding in leguminous crops has led to the induction of an improved L 114 soybean mutant that is shorter that the original variety but yield about 40% more. Several PAEC mungbean varieties characterized with long pods that are non-shattering were also induced. In asexually propagated crops, an increase in yield and chlorophyll mutants were obtained in sweet potatos. Likewise, chlorophyll mutant which look-like 'ornamental bromeliads' and a mutant with reduced spines have been developed in pineapple Queen variety. At present, we have started a new project in mutation breeding in ornamentals. Tissue culture is being utilized in our mutation breeding program. In the near future, radiation induced mutagenesis coupled with in vitro culture techniques on protoplast culture and somatic hybridization will be integrated into our mutation breeding program to facilitate the production of new crop varieties. (author)
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Achievements in NS rapeseed hybrids breeding
Directory of Open Access Journals (Sweden)
Marjanović-Jeromela Ana
2016-01-01
Full Text Available The increased production of oilseed rape (Brassica napus L. is evident on a global scale, but also in Serbia in the last decade. Rapeseed is used primarily for vegetable oil and processing industry, but also as a source of protein for animal feed and green manure. Following the cultivation of varieties, breeding and cultivation of hybrid rapeseed started in the 1990's, to take advantage of heterosis in F1 generation, while protecting the breeder's rights during seed commercialization. The breeding of hybrid oilseed rape requires high quality starting material (lines with good combining abilities for introduction of male sterility. Ogura sterility system is primarily used at the Institute of Field and Vegetable Crops, Novi Sad, Serbia. To use this system, separate lines are modified with genes for cytoplasmic male sterility (cms female line - mother line and restoration of fertility (Rf male lines - father line. In order to maintain the sterility of the mother line it is necessary to produce a maintainer line of cytoplasmic male sterility. Creation of these lines and hybrids at the Institute of Field and Vegetable Crops was successfully monitored with intense use of cytogenetic laboratory methods. The structure and vitality of pollen, including different phases during meiosis were checked so that cms stability was confirmed during the introduction of these genes into different lines. Rapeseed breeding program in Serbia resulted in numerous varieties through collaboration of researchers engaged in breeding and genetics of this plant species. So far, in addition to 12 varieties of winter rapeseed and two varieties of spring rapeseed, a new hybrid of winter rapeseed NS Ras was registered in Serbia. NS Ras is an early-maturing hybrid characterized by high seed yield and oil content. Average yield of NS Ras for two seasons and three sites was 4256 kg ha-1 of seed and 1704 kg ha-1 of oil. Three promising winter rapeseed hybrids are in the process of
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Plant breeding: Induced mutation technology for crop improvement
International Nuclear Information System (INIS)
Novak, F.J.; Brunner, H.
1992-01-01
Plant breeding requires genetic variation of useful traits for crop improvement, but the desired variation is often lacking. Mutagenic agents, such as radiation and certain chemicals, can be used to induce mutations and generate genetic variations from which desirable mutants may be selected. After a brief summary of the methods currently employed in plant breeding, especially those inducing genetic engineering, this article describes the activities of the Plant Breeding Unit of the IAEA Laboratories at Seibersdorf, summarizing the research and development areas currently being pursued. The banana plant is chosen to exemplify the Laboratories' research
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Seasonal organic pig production with a local breed
DEFF Research Database (Denmark)
Kongsted, Anne Grete; Claudi-Magnussen, C.; Horsted, Klaus
2009-01-01
It is important that organic pork differs markedly from conventional pork regarding taste, appearance and production methods in order to overcome the heavy price competition. That is the hypothesis behind thecurrent project. A seasonal outdoor rearing system based on a traditional and local breed...... to the modern genotype and thefat of the Black-Spotted pig was characterised as having a special nutty taste. In conclusion, preliminaryresults indicate that the local breed differs markedly with respect to several meat quality aspects comparedto the modern breed but also shows clear disadvantages regarding...
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Genetic diversity revealed by AFLP markers in Albanian goat breeds
Directory of Open Access Journals (Sweden)
Hoda Anila
2012-01-01
Full Text Available The amplified fragment length polymorphism (AFLP technique with three EcoRI/TaqI primer combinations was used in 185 unrelated individuals, representative of 6 local goat breeds of Albania, and 107 markers were generated. The mean Nei’s expected heterozygosity value for the whole population was 0.199 and the mean Shannon index was 0.249, indicating a high level of within-breed diversity. Wright’s FST index, Nei’s unbiased genetic distance and Reynolds’ genetic distance were calculated. Pairwise Fst values among the populations ranged from 0.019 to 0.047. A highly significant average FST of 0.031 was estimated, showing a low level of breed subdivision. Most of the variation is accounted for by differences among individuals. Cluster analysis based on Reynolds’ genetic distance between breeds and PCA were performed. An individual UPGMA tree based on Jaccard’s similarity index showed clusters with individuals from all goat breeds. Analysis of population structure points to a high level of admixture among breeds.
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POPULATION AND BREEDING OF THE GENTOO PENGUIN ...
African Journals Online (AJOL)
The numbers of gentoo penguins Pygoscelis papua breeding at subantarctic Marion Island fell by 40% from 1994/95 to 2002/03, from 1 352 pairs to 806 pairs. Apart from a slight increase in 1998/99, there was a steady decrease in numbers breeding between 1995/96 and 2000/01, when the population stabilized. There is ...
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Arcadio Morales-Pérez; Elizabeth Nava-Aguilera; Alejandro Balanzar-Martínez; Antonio Juan Cortés-Guzmán; David Gasga-Salinas; Irma Esther Rodríguez-Ramos; Alba Meneses-Rentería; Sergio Paredes-Solís; José Legorreta-Soberanis; Felipe Gil Armendariz-Valle; Robert J. Ledogar; Anne Cockcroft; Neil Andersson
2017-01-01
Abstract Background Understanding the breeding patterns of Aedes aegypti in households and the factors associated with infestation are important for implementing vector control. The baseline survey of a cluster randomised controlled trial of community mobilisation for dengue prevention in Mexico and Nicaragua collected information about the containers that are the main breeding sites, identified possible actions to reduce breeding, and examined factors associated with household infestation. T...
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Fashion vs. function in cultural evolution: the case of dog breed popularity.
Ghirlanda, Stefano; Acerbi, Alberto; Herzog, Harold; Serpell, James A
2013-01-01
We investigate the relationship between characteristics of dog breeds and their popularity between years 1926 and 2005. We consider breed health, longevity, and behavioral qualities such as aggressiveness, trainability, and fearfulness. We show that a breed's overall popularity, fluctuations in popularity, and rates of increase and decrease around popularity peaks show typically no correlation with these breed characteristics. One exception is the finding that more popular breeds tend to suffer from more inherited disorders. Our results support the hypothesis that dog breed popularity has been primarily determined by fashion rather than function.