Search results for "Reproduction"

Reproductive Physiology ofAedes(Aedimorphus)vexans(Diptera: Culicidae) in Relation to Flight Potential

2001

Total protein, lipid, and glycogen of Aedes vexans (Meigen) were related linearly to body size at eclosion. Starvation after emergence led to the determination of minimal irreducible amounts of protein, lipid, and glycogen and the availability of the teneral reserves, whereas access to sucrose revealed the potential for reserve synthesis. Glycogenesis and lipogenesis increased reserves approximately 10-fold the teneral value within 1 and 2 wk after emergence, respectively. Carbohydrate feeding was an essential behavior before blood feeding and oogenesis commenced. Female flight was tested on a flight mill. Maximal flights of 10-17 km in a single night occurred at 2 wk posteclosion and paral…

Maternal antibody transmission and breeding densities in the Black-headed Gull Larus ridibundus

2004

1. The offspring of avian species, especially those of colonial breeders, are exposed to a number of pathogens immediately after birth. The chick's immune system is, at that early stage still immature and inefficient. As a consequence, diseases can have a strong impact on chick survival.2. The ability of mothers to transmit passive immunity in terms of antibodies of their own acquired immunity to their chicks is probably an essential pathway to enhance the chick survival. Since the production of antibodies is costly, females are expected to adjust the transmission of passive immunity to the local disease environment.3. We found that in Black-headed Gulls (Larus ridibundus L.) yolk antibody …

Transgenerational immunity in a bird-ectoparasite system: do maternally transferred antibodies affect parasite fecundity or the offspring's susceptib…

2009

During egg formation, female birds deposit antibodies against parasites and pathogens they were exposed to before egg laying into the yolk. In captive bird species, it has been shown that these maternal immunoglobulins (maternal yolk IgGs) can protect newly hatched offspring against infection. However, direct evidence for such benefits in wild birds is hitherto lacking. We investigated (1) if nestling Great Tits Parus major originating from eggs with naturally high levels of maternal yolk IgG are less susceptible to a common, nest-based ectoparasite, (2) if maternal yolk IgGs influence nestling development and in particular, their own immune defence, and (3) if there is a negative correlati…

Validation and application of a PCR primer set to quantify fungal communities in the soil environment by real-time quantitative PCR

2011

Fungi constitute an important group in soil biological diversity and functioning. However, characterization and knowledge of fungal communities is hampered because few primer sets are available to quantify fungal abundance by real-time quantitative PCR (real-time Q-PCR). The aim in this study was to quantify fungal abundance in soils by incorporating, into a real-time Q-PCR using the SYBRGreen (R) method, a primer set already used to study the genetic structure of soil fungal communities. To satisfy the real-time Q-PCR requirements to enhance the accuracy and reproducibility of the detection technique, this study focused on the 18S rRNA gene conserved regions. These regions are little affec…

Overwintering strategies of a boreal small mammal in a changing climate

2015

Sex-specific genetic differences in endurance swimming of Trinidadian guppies.

2015

Abstract Swim performance is considered a main fitness‐determining trait in many aquatic organisms. Swimming is generally the only way most aquatic prey can escape predation, and swimming capacity is directly linked to food capture, habitat shifts, and reproduction. Therefore, evolutionary studies of swim performance are important to understand adaptation to aquatic environments. Most studies, however, concentrate on the importance of burst‐swim responses to predators, and little is known about its effect on endurance. Even fewer studies associate differences in organism swim capabilities to key gender‐specific responses. In this experiment, we assess the gender‐specific genetic basis of sw…

Fecundity determines the outcome of founding queen associations in ants

2021

AbstractAnimal cooperation evolved because of its benefits to the cooperators. Pleometrosis in ants - the cooperation of queens to found a colony - benefits colony growth, but also incurs costs for some of the cooperators because only one queen usually survives the association. While several traits are associated with queen survival, they tend to be confounded and it is unclear which factor specifically determines the outcome of pleometrosis. In this study, we used the ant Lasius niger to monitor offspring production in colonies founded by one or two queens. Then, we experimentally paired queens that differed in fecundity but not in size, and vice versa, to disentangle the effect of these f…

Factors affecting breeding dispersal of European ducks on Engure Marsh, Latvia

2003

Summary 1 We used up to 35 years of capture–recapture data from nearly 3300 individual female ducks nesting on Engure Marsh, Latvia, and multistate modelling to test predictions about the influence of environmental, habitat and management factors on breeding dispersal probability within the marsh. 2 Analyses based on observed dispersal distances of common pochards and tufted ducks provided no evidence that breeding success in year t influenced dispersal distance between t and t+ 1. 3 Breeding dispersal distances (year t to t+ 1) of pochards and tufted ducks were associated with a delay in relative nest initiation dates in year t+ 1. The delay was greater for pochards (c. 4 days) than for tu…

La reproducció en la vida de les dones. Aportacions de l'antropologia

2012

L’antropologia social i cultural ha estudiat la reproducció des del punt de vista de diverses especialitats –parentiu, simbolisme, feminisme, salut– i ha assenyalat tant les dimensions que comprèn com el caràcter social, construït i central per al manteniment d’una societat. Aquesta mirada permet a les autores suggerir certes hipòtesis a partir de les quals entendre la reproducció com un assumpte vertebrador de la vida de les dones en l’actualidad, que hauria de ser objecte d’estudi rellevant per a la ciència.

Adopción en casos especiales y unidad del status filiationis en el derecho italiano: ¿cómo repercute en el plano sucesorio?

2022

In the Italian legal system, there has recently been recognition by the Constitutional Court in adoptions in particular cases of the existence of civil relations between the adoptee and the relatives of the adopter, thus equalizing the margins of protection of minors, regardless of the situations of fact or law from which the new status of the child originated. This jurisprudential work is full of considerable systematic reflections and is intended to be applied not only to the hypothesis of adoption by same-sex couples, but also to all those cases in which a state of semi-permanent abandonment or cyclical abandonment occurs. Notwithstanding the negative value directed at the forms of surro…