Reproductive strategies and chromosomal aberrations affect survival in the Rivuliid fish Hypsolebias sertanejo

Zygote ◽  
2020 ◽  
pp. 1-7
Author(s):  
Mariana Machado Evangelista ◽  
Elizabeth Romagosa ◽  
Diógenes Henrique Siqueira-Silva ◽  
George Shigueki Yasui ◽  
Takafumi Fujimoto ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Reproductive Success ◽  
Reproductive Strategies ◽  
Chromosomal Abnormalities ◽  
Reproductive Behaviour ◽  
Conservation Strategies ◽  
Hatching Rate ◽  
Natural Conditions ◽  
And Performance ◽  
Ploidy Status

Summary Rivulidae comprises a family of fish largely distributed in Brazil that includes 201 species, of which 125 are considered endangered. This fact emphasizes the need for development of conservation strategies including studies on genetics and reproduction. In this paper, we describe aspects of biology and reproduction of the rivuliid species Hypsolebias sertanejo. We outline the reproductive behaviour of this species under laboratory conditions, analyze ploidy status by flow cytometry, describe reproductive behaviour and performance and test dry and wet incubation of eggs. Although H. sertanejo showed well known patterns of reproductive behaviour, we verified many peculiarities inherent to its reproductive biology. As expected, most individuals were diploid (87.71%), however 14.29% were considered mosaics. Although no sterility was observed within mosaics, infertility of these fish was not fully evaluated. Hatching rate of the eggs collected was very low following both dry and wet incubation (5.04 and 3.79%, respectively). These results provide interesting information regarding the reproductive success of this species, and suggest that chromosomal abnormalities described may reduce the survival of H. sertanejo under natural conditions, limiting the perpetuation of this species, and emphasizing the need for more preservation efforts, including artificial propagation and gene banking.

Heat-induced triploids in Brycon amazonicus: a strategic fish species for aquaculture and conservation

Zygote ◽  
2021 ◽  
pp. 1-5
Author(s):  
Nivaldo Ferreira do Nascimento ◽  
Rafaela Manchin Bertolini ◽  
Lucia Soares Lopez ◽  
Laura Satiko Okada Nakaghi ◽  
Paulo Sérgio Monzani ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Heat Shock ◽  
Early Development ◽  
Fish Species ◽  
Survival Rates ◽  
Shock Treatment ◽  
Hatching Rate ◽  
Heat Shock Treatment ◽  
Control Survival ◽  
Ploidy Status

Summary Triploidization plays an important role in aquaculture and surrogate technologies. In this study, we induced triploidy in the matrinxã fish (Brycon amazonicus) using a heat-shock technique. Embryos at 2 min post fertilization (mpf) were heat shocked at 38°C, 40°C, or 42°C for 2 min. Untreated, intact embryos were used as a control. Survival rates during early development were monitored and ploidy status was confirmed using flow cytometry and nuclear diameter analysis of erythrocytes. The hatching rate reduced with heat-shock treatment, and heat-shock treatments at 42°C resulted in no hatching events. Optimal results were obtained at 40°C with 95% of larvae exhibiting triploidy. Therefore, we report that heat-shock treatments of embryos (2 mpf) at 40°C for 2 min is an effective way to induce triploid individuals in B. amazonicus.

Seasonally contrasting life-history strategies in the land snail Cornu aspersum: physiological and ecological implications

2010 ◽  
Vol 88 (10) ◽  
pp. 995-1002 ◽  
Author(s):  
A. Nicolai ◽  
J. Filser ◽  
V. Briand ◽  
M. Charrier
Keyword(s):  
Life History ◽  
Reproductive Success ◽  
Reproductive Strategies ◽  
Energy Content ◽  
Reproductive Traits ◽  
Land Snails ◽  
Life History Strategies ◽  
Hatching Rate ◽  
Trade Offs ◽  
Cornu Aspersum

When a life history is characterized by both seasonality in reproduction and seasonality in offspring fitness, trade-offs in reproductive traits might be adjustments to seasonal time constraints to optimize reproductive success. Therefore, we compared in the laboratory the trade-offs in reproductive traits between early (after maturity) and delayed (after dormancy) reproduction in young land snails Cornu aspersum (Müller, 1774) (syn. Helix aspersa ), depending on food energy content. We also investigated the maternal investment in reproductive output in both breeding periods. After attaining maturity, snails produced single clutches with many small eggs, which resulted, in contrast to previous studies, in large offspring with a low hatching rate owing to high within-clutch cannibalism. The young cannibals may have a higher survival probability in the following hibernation. Snails starting to reproduce after hibernation had smaller clutches of larger eggs, resulting in high quantity of lighter offspring. The clutch mass was positively correlated with maternal mass in snails reproducing after having attained maturity and negatively correlated in snails reproducing after hibernation. Multiple oviposition occurred only after hibernation, thereby enhancing reproductive success. An energy-rich diet did not affect reproductive strategies. Further studies should focus on seasonal plasticity of reproductive strategies in natural populations of C. aspersum and investigate survival probabilities of breeders and juveniles in an evolutionary context.

scholarly journals Male parent birds exert more effort to reproduce in two desert passerines

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Donghui Ma ◽  
Mengjie Lu ◽  
Zhichang Cheng ◽  
Xingnan Du ◽  
Xiaoyu Zou ◽  
...  
Keyword(s):  
Reproductive Output ◽  
Female Parent ◽  
Northwest China ◽  
Reproductive Behaviour ◽  
Male Parent ◽  
Hatching Rate ◽  
Feeding Rates ◽  
Passerine Species ◽  
Arid Desert ◽  
Habitat Environment

Abstract Background Parental investment by birds is limited by the habitat environment, and a male parent increases its effort to reproduce in birds that live in high-altitude areas. Methods A study of the reproductive behaviour of the Saxaul Sparrow (Passer ammodendri) and the Isabelline Shrike (Lanius isabellinus) was carried out at the Gansu An’xi Extremely Arid Desert National Nature Reserve in northwest China to determine the reproductive input of passerine species in desert habitats. Results In Saxaul Sparrows, compared to the female parent, the male parent exhibited a significantly higher frequency of nest-defense behaviour (chirping and warning) during nesting, hatching and feeding periods. In addition, in comparison to the female parent, the male parent exhibited almost equal frequencies of nesting and incubation but fed nestlings significantly more times. Similar to the male sparrows, the feeding rates of the male Isabelline Shrikes were significantly higher than those of the females. The hatching rate and fledging rate of the Saxaul Sparrow on average in this study were 81.99 and 91.92%, respectively, while those of the shrike were 69.00 and 96.53%, respectively. Conclusions These two different passerine species living in the same desert environment exhibited the same trend in their reproductive investments. Adapting to desert environments is a strategy that may have evolved in passerines where male parent birds put more effort than females into reproduction to ensure high reproductive output.

Reproductive Autonomy and Evolutionary Biology: A Regulatory Framework for Trait-Selection Technologies

1993 ◽  
Vol 19 (3) ◽  
pp. 187-231
Author(s):  
Owen D. Jones
Keyword(s):  
Reproductive Success ◽  
Supreme Court ◽  
Reproductive Strategies ◽  
Evolutionary Biology ◽  
Social Values ◽  
Inclusive Fitness ◽  
Regulatory System ◽  
Regulatory Framework ◽  
Reproductive Autonomy ◽  
Future Child

The Constitution protects, in some measure, each person's autonomy in making basic decisions about family, parenthood, and procreation. This Article examines the extent to which courts should protect from government intrusions a parent's access to technologies that influence specific characteristics of offspring. Beginning with Supreme Court opinions that articulate constitutional and social values regarding reproductive autonomy, the Article explores how important new insights from evolutionary biology may supplement an understanding of Human procreation. Specifically, the Article explains how trait selection can constitute an important part of larger “reproductive strategies” that powerfully affect an individual's “inclusive fitness” (itself a measure of reproductive success). It concludes that access to trait-selection technologies should receive the same federal protection from government intrusions as that afforded access to abortion. It proposes the first limit to that protection, however, when a parent seeks to select for a trait, or to use a technique, that would be clearly and significantly damaging to the future child. The Article subsequently divides the use of trait-selection technologies (TSTs) into eight contexts and proposes a preliminary framework by which a regulatory system could legitimately distinguish among them.

scholarly journals The Effect of Weak Electrolyte Solutions on the Hatching Rate of the Eggs of Tricho-Strongylus Retortaeformis (Zeder) and its Interpretation in Terms of a Proposed Hatching Mechanism of Strongyloid Eggs

1958 ◽  
Vol 35 (3) ◽  
pp. 584-601
Author(s):  
P. A. G. WILSON
Keyword(s):  
Water Permeability ◽  
Electrolyte Solutions ◽  
Hatching Rate ◽  
Natural Conditions ◽  
Ionic Solutions ◽  
Rate Of Increase ◽  
Egg Membrane ◽  
Hatching Eggs ◽  
Colligative Properties

1. The influence of solutions of NaCl on the hatching of eggs of Trichostrongylus retortaeformis is studied. It is shown that the effects are not the consequence of colligative properties, but are related to ionic phenomena. 0.05 N-NaCl slows down the rate of hatch without impairing the ultimate ‘hatchability’ of the eggs. Processes of development up to hatching are not slowed down. 2. The effect demonstrated in the case of NaCl is shown to be shared by eight other electrolytes, the depression in the rate of hatch being proportional to the mobility of the ions in solution. On the assumption that the effect of the ions is due to a penetration of the egg membrane(s) the rate of entry is shown to be controlled by the speed of the slower ion in any one salt. 3. The influence of NaCl on the permeability of hatching eggs to water is studied. It is shown that the rate of increase in permeability is slowed down sufficiently in NaCl to control the rate of hatch. The inference that water permeability is a necessary prerequisite for hatching is made, a further hypothetical process being invoked to account for the rate of hatch in the absence of NaCl, since it is not then controlled by changes in water permeability. 4. The probability that the net effect of ionic solutions on the eggs is one concerned with the rate of breakdown of the inner wax-like layer of the egg is strengthened by experiments demonstrating that the depressing influence of NaCl is antagonized by ‘Teepol’, though the comparable influence of other, non-emulsifying, compounds cannot be explained. 5. The role of water permeability in the hatching mechanism is investigated. 6. A hatching mechanism of strongyloid eggs is proposed which involves two processes, the first dependent upon the osmotic relationships of the unhatched larva to its environment, the second being some sort of chemical weakening of the outer shell. 7. It is suggested that the effect of ions on hatching rate assists the ‘embryonated egg’ to survive under natural conditions when the hatched first-stage larva might otherwise be destroyed by desiccation.

scholarly journals Low sperm to egg ratio required for successful in vitro fertilisation in a pair-spawning teleost, Senegalese sole (Solea senegalensis)

2020 ◽  
Author(s):  
Sandra Ramos-Júdez ◽  
Wendy Ángela González-López ◽  
Jhons Huayanay Ostos ◽  
Noemí Cota Mamani ◽  
Carlos Marrero Alemán ◽  
...  
Keyword(s):  
Large Scale ◽  
Reproductive Behaviour ◽  
Poor Quality ◽  
Solea Senegalensis ◽  
In Vitro Fertilisation ◽  
Hatching Rate ◽  
Senegalese Sole ◽  
Single Male ◽  
Close Proximity

AbstractCultured Senegalese sole (Solea senegalensis) breeders fail to spawn fertilised eggs and this bottleneck could be solved with the implementation of large-scale in vitro fertilisation protocols. However, low production of poor-quality sperm has frustrated the development of in vitro fertilisation protocols. Cultured females were induced to ovulate with a 5 µg kg-1 single injection of gonadotropin releasing hormone agonist (GnRHa) and good quality eggs (82.6 ± 9.2% fertilisation) were stripped 41:57 ± 1:46 h after the injection. Sperm was collected from cultured males, diluted in modified Leibovitz and used fresh to fertilise the eggs. A non-linear regression, an exponential rise to a maximum (R = 0.93, P < 0.0001) described the number of motile spermatozoa required to fertilise a viable egg and 1617 motile spermatozoa were sufficient to fertilise 99 ± 12% (± 95% CI) of viable eggs. Similar, spermatozoa egg-1 ratios of 592 ± 611 motile spermatozoa egg-1 were used in large-scale in vitro fertilisations with 190,512 ± 38,471 eggs. The sperm from a single male (145 ± 50 µL or 8.0 ± 6.8 × 108 spermatozoa) was used to fertilise the eggs. The mean hatching rate of the large-scale in vitro fertilisations was 70 ± 14 % to provide 131,540 ± 34,448 larvae per fertilisation. When unfertilised eggs were stored at room temperature the percentage of viable eggs decreased gradually and indicated the sooner eggs were fertilised after stripping the higher the viability of the eggs. The collection of sperm directly into a syringe containing modified Leibovitz significantly increased the percentage of motile spermatozoa (33.4 ± 12.2 %) compared to dilution in modified Leibovitz immediately after collection (6.6 ± 4.9 %). Senegalese sole have a pair-spawning reproductive behaviour characterised by external gamete fertilisation in close proximity with no sperm competition. The low spermatozoa egg-1 ratio required for maximum fertilisation was consistent with this reproductive behaviour and strategy. The provision of a large-scale in vitro fertilisation protocol (200 µL of sperm per 100 mL of eggs) will enable the industry to operate sustainably and implement breeding programs to improve production.

scholarly journals A template method for decomposing flow cytometry histograms of human chromosomes.

1979 ◽  
Vol 27 (1) ◽  
pp. 305-310 ◽  
Author(s):  
D H Moore
Keyword(s):  
Flow Cytometry ◽  
Trisomy 21 ◽  
Chromosomal Abnormalities ◽  
Simulated Data ◽  
Normal Karyotype ◽  
Template Method ◽  
Normal Person ◽  
Human Chromosomes ◽  
Metaphase Chromosomes ◽  
Flow Measurements

A new method for decomposing flow cytometry histograms of isolated human metaphase chromosomes is described and tested. The method is based on fitting a template, composed of the means of all chromosomes of a normal karyotype to the flow histogram. The utility of the method is demonstrated by application to flow measurements of chromosomes from a normal person and comparing the results with those obtained by conventional cytophotometry. The power of the method for detecting gross chromosomal abnormalities, such as trisomy 21, as well as more subtle variations such as a single translocation, is determined for simulated data.

Male reproductive behaviour and spawning success in a temperate zone goby, Coryphopterus nicholsi

1982 ◽  
Vol 60 (10) ◽  
pp. 2309-2316 ◽  
Author(s):  
Kathleen S. Cole
Keyword(s):  
Reproductive Success ◽  
Standard Length ◽  
Reproductive Behaviour ◽  
Reproductive Season ◽  
Temperate Zone ◽  
Testicular Development ◽  
Male Size ◽  
Size Standard ◽  
Highly Correlated ◽  
Spawning Success

Coryphopterus nicholsi is a temperate zone marine goby. In laboratory groups of fish, females preferentially spawn with dominant males; assessment of dominance appears to be based upon courting vigour. Male size (standard length) and dominance were often, but not always, highly correlated. In contrast, there was no consistent correlation between territorial quality and spawning success. Smaller males in laboratory groups did not court females or guard eggs. However, their behaviour and testicular development during the reproductive season suggest that they may engage in sneak spawning. Dominant males are more likely to successfully guard eggs against conspecific predators than are subordinate males, and hence females should have greater reproductive success if they choose dominant males for spawning partners.

Feminist and Evolutionary Perspectives of Female-Female Competition, Status Seeking, and Social Network Formation

2015 ◽  
Author(s):  
Laurette T. Liesen
Keyword(s):  
Social Networks ◽  
Social Network ◽  
Reproductive Success ◽  
Reproductive Strategies ◽  
Network Formation ◽  
Female Competition ◽  
Status Seeking ◽  
Social Network Formation ◽  
Evolutionary Perspectives

During the 1980s and 1990s, feminist evolutionists were instrumental in demonstrating that primate females, including girls and women, can be aggressive and seek status within their groups. Building on their insights, researchers from across disciplines have found that females use a variety of direct and indirect tactics as they pursue their reproductive success. To better understand women’s aggression and status seeking, one also must examine their social networks. Women must not only deal with the dynamics within their groups, they also must deal with pressures from other groups. Success in maintaining connections in one’s social network is vital for access to the various resources women need for their own reproductive success and to keep competitors in check. Overall, women’s social networks, while serving both supportive and competitive functions, profoundly impact on the reproductive future of women and especially the survival and future reproductive strategies of their children.

Mating status of coexisting conspecific individuals modulate reproduction in a ladybird, Menochilus sexmaculatus

2021 ◽  
Vol 71 (2) ◽  
pp. 197-214
Author(s):  
Shashwat Singh ◽  
Geetanjali Mishra ◽  
Omkar
Keyword(s):  
Reproductive Success ◽  
Early Onset ◽  
Crucial Role ◽  
Reproductive Behaviour ◽  
Reproductive Parameters ◽  
Mating Status ◽  
Ladybird Beetle ◽  
Close Vicinity ◽  
Offspring Fitness ◽  
Petri Dishes

Abstract The mating status of organisms plays a crucial role in deciphering mating decision and reproductive success of any organisms. Odour or pheromones are known to be perceived by animals through olfaction to locate mates at a distance. In this study, an attempt was made to investigate the effect of the presence of unmated and mated conspecific adults on mating and reproductive parameters of the ladybird beetle, Menochilus sexmaculatus (Fabricius, 1781). To conduct this experiment, an arena was made with the help of two Petri dishes and in such a manner that the experimental adults were only able to perceive the presence of conspecific adults of different mating status in their close vicinity. The results of the study demonstrated an early onset of mating in the presence of males compared to females. Another male in the vicinity poses competition that may force the males to establish genital contact faster. In the absence of any potential rival, copulation duration was highest. Females laid more eggs in the presence of mated females. This may be to increase offspring fitness in the presence of potential competitors for the already mated female. Females laid fewer eggs in the presence of unmated females. Unmated females nearby can be another choice for a male and thus, the male possibly limits the size of the ejaculate containing oviposition stimulants. The current study advocates that mating and reproductive behaviour are modulated according to the perceived surroundings in the form of conspecific adults of different mating status.

Sign in / Sign up

Export Citation Format

Share Document