scholarly journals Relatedness modulates reproductive competition among queens in ant societies with multiple queens

2021 ◽  
Author(s):  
Heikki Helanterä ◽  
Martina Ozan ◽  
Liselotte Sundström
Keyword(s):  
Physiological State ◽  
Egg Laying ◽  
Reproductive Status ◽  
Reproductive Competition ◽  
Animal Groups ◽  
Conflict And Cooperation ◽  
Kin Competition ◽  
Formica Fusca ◽  
External Conditions ◽  
Fine Tune

Reproductive sharing in animal groups with multiple breeders, insects and vertebrates alike, contains elements of both conflict and cooperation, and depends on both relatedness between co-breeders, as well as their internal and external conditions. We studied how queens of the ant Formica fusca adjust their reproductive efforts in response to experimental manipulations of the kin competition regime in their nest, as well as their own reproductive status. Queens respond to the presence of competitors by increasing their egg laying efforts, but only if the competitors are highly fecund and distantly related. Furthermore, queens only engage in cannibalism of eggs when the risk of erroneously destroying own offspring is absent. We demonstrate that queens of Formica fusca fine-tune their behaviours in response to kinship and fecundity of others as well as their own physiological state in an unusually precise manner.

scholarly journals Environment and Local Substrate Availability Effects on Harem Formation in a Polygynous Bark Beetle

Insects ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 98 ◽  
Author(s):  
Melissa J. Griffin ◽  
Matthew R. E. Symonds
Keyword(s):  
Population Density ◽  
Bark Beetle ◽  
Substrate Availability ◽  
Pine Plantation ◽  
Single Male ◽  
Animal Groups ◽  
Ips Grandicollis ◽  
Surrounding Environment ◽  
External Conditions ◽  
Species Groups

Many forms of polygyny are observed across different animal groups. In some species, groups of females may remain with a single male for breeding, often referred to as “harem polygyny”. The environment and the amount of habitat available for feeding, mating and oviposition may have an effect on the formation of harems. We aimed to determine how the surrounding environment (a harvested or unharvested pine plantation) and availability of local substrate affect the harems of the bark beetle, Ips grandicollis (Coleoptera: Curculionidae: Scolytinae). In a harvested pine plantation with large amounts of available habitat, the population density of these beetles is much higher than in unharvested plantations. We found the number of females per male to be significantly greater in the harvested plantation than the unharvested one. Additionally, the amount of substrate available in the immediate local vicinity (the number of logs in replicate piles) also influences the number of beetles attracted to a log and size of individual harems. We also examined how females were distributing themselves in their galleries around the males’ nuptial chamber, as previous work has demonstrated the potential for competition between neighbouring females and their offspring. Females do not perform clumping, suggesting some avoidance when females make their galleries, but they also do not distribute themselves evenly. Female distribution around the male’s nuptial chamber appears to be random, and not influenced by other females or external conditions.

Productivity of laying hens when fed probiotic feed additive Amilocin

2021 ◽  
pp. 43-57
Author(s):  
P. P. Kornienko ◽  
E. G. Martynova
Keyword(s):  
Laying Hens ◽  
Physiological State ◽  
Live Weight ◽  
Positive Influence ◽  
Research Data ◽  
Egg Laying ◽  
Biologically Active ◽  
Feed Additive ◽  
Active Components ◽  
Normal Microflora

The possibilities of increasing the productivity of different poultry species by increasing the absorption of feed nutrients can be realized through the use of new biologically active components that are usually added to traditional feed based on live cultures of microorganisms of the normal microflora of the gastrointestinal tract. The effectiveness of different probiotic drugs varies depending on the types and strains of microorganisms that are included in their composition, the dose of the drug, the scheme of its use, age, type, physiological state and productivity of animals. The research has been carried out to study the influence of the use of the probiotic feed additive Amilocin in the diets of laying hens of the cross Hisex Brown on their productivity. The positive influence of the studied feed additive on the live weight and livability of laying hens, egg productivity, quality and quantity of eggs obtained, morphological and biochemical parameters of the blood of experimental poultry, slaughter parameters and chemical composition of the meat of experimental laying hens has been established. The optimal rate of introduction of probiotic feed additive Amilocin into the diet of laying hens has been determined (0,5 g/head/day at the beginning of egg laying during 10 days, 1,0 g/head/day at the peak of egg laying during 10 days, followed by 1 g/head/day monthly for 10 days until the end of egg laying). The economics effectiveness of using the probiotic feed additive Amilocin per 1,0 ruble of costs was 1,24– 1,35 ruble. According to the research data recommendations for the use of the probiotic feed additive Amilocin have been proposed.

scholarly journals Transformations at High Latitudes: Why do Red Knots Bring Body Stores to the Breeding Grounds?

The Condor ◽  
2005 ◽  
Vol 107 (2) ◽  
pp. 449-457 ◽  
Author(s):  
R. I Guy Morrison ◽  
Nick C. Davidson ◽  
Theunis Piersma
Keyword(s):  
Physiological State ◽  
High Arctic ◽  
Egg Laying ◽  
Concomitant Increase ◽  
Rapid Loss ◽  
Major Function ◽  
Calidris Canutus ◽  
Egg Formation ◽  
Breeding Grounds ◽  
Gut Length

Abstract We examined changes in body composition of Red Knots (Calidris canutus islandica) following arrival on their High Arctic breeding grounds at Alert, Ellesmere Island, Canada. Knots arrived in late May and early June with large fat and muscle stores. In the next two weeks, fat and protein stores (pectoral muscles) declined, while increases occurred in gizzard, proventriculus, gut length, heart, liver, and possibly gonads. Most stores were used before egg laying occurred and were therefore not available for egg formation. Early development of ova in some females suggests that body stores may be incorporated into the earliest eggs. While stores may be used for survival when conditions are difficult after arrival, their rapid loss and the concomitant increase in other organs suggests that a major function may be to facilitate a transformation from a physiological state suitable for migration to one suitable, and possibly required, for successful breeding. Transformaciones a Altas Latitudes: ¿Por qué Calidris canutus islandica Lleva Reservas Corporales a los Sitios de Nidificación? Resumen. Examinamos los cambios en la condición corporal de individuos de Calidris canutus islandica luego de que éstos llegaran a sus territorios reproductivos a altas latitudes en el Ártico en Alert, isla Ellesmere, Canadá. Los individuos de C. c. islandica llegaron a fines de mayo y comienzos de junio con grandes reservas de grasa y músculo. Durante las dos semanas siguientes, las reservas de grasa y proteína (músculos pectorales) disminuyeron, mientras que la molleja, los proventrículos, el largo del intestino, el hígado y posiblemente las gónadas aumentaron de tamaño. La mayoría de las reservas fueron usadas antes del período de puesta de huevos, por lo que éstas no estuvieron disponibles para la formación de los huevos. En algunas hembras, el desarrollo temprano de los óvulos sugiere que las reservas corporales pueden ser incorporadas en los primeros huevos. Si bien las reservas pueden ser usadas para sobrevivir en el momento de la llegada cuando las condiciones son difí ciles, su rápida pérdida y el aumento concomitante en otros órganos sugiere que una de las funciones principales de las reservas podría ser facilitar la transformación de un estado fisiológico apropiado para la migración a un estado apropiado y posiblemente requerido para la reproducción exitosa.

scholarly journals Factors affecting individual variation in nest-defense intensity in colonially breeding Black-tailed Gulls (Larus crassirostris)

2011 ◽  
Vol 89 (10) ◽  
pp. 938-944 ◽  
Author(s):  
Kentaro Kazama ◽  
Yasuaki Niizuma ◽  
Kentaro Q. Sakamoto ◽  
Yutaka Watanuki
Keyword(s):  
Individual Variation ◽  
Physiological State ◽  
Breeding Birds ◽  
Egg Laying ◽  
Nest Defense ◽  
Laying Date ◽  
Plasma Testosterone ◽  
Factors Affecting ◽  
Corvus Macrorhynchos ◽  
Males And Females

The physiological state of parent birds combined with the value of their clutch may affect the intensity of their nest defense. In colonially breeding birds, nest-defense intensity may also be affected by the behavior of neighbors. We investigated individual variation in the nest-defense intensity among colonial Black-tailed Gulls ( Larus crassirostris Vieillot, 1818) over 2 years. Only 30%–40% of males attacked a decoy of an egg predator (Large-billed Crow ( Corvus macrorhynchos Wagler, 1827)), and the other males and females rarely attacked. Males attacking the decoy had higher levels of plasma testosterone than males that did not attack. Each male’s, but not female’s, nest-defense intensity was consistent throughout the incubation period and also across years. The intensity was not related to egg-laying date, clutch size, or age of offspring. The intensity was likely to be higher when individuals had one or more neighbors, representing higher nest-defense intensity in the year where gulls had larger number of adjacent neighboring nests (5.23 nests), but this trend was not observed in the year where they had smaller number of the neighboring nests (3.73 nests). Thus, in addition to testosterone levels, behavior of neighbors also influences the nest-defense intensity.

scholarly journals The value of oviposition timing, queen presence and kinship in a social insect

2013 ◽  
Vol 280 (1766) ◽  
pp. 20131231 ◽  
Author(s):  
Martina Ozan ◽  
Heikki Helanterä ◽  
Liselotte Sundström
Keyword(s):  
Social Insect ◽  
Breeding Phenology ◽  
Reproductive Competition ◽  
Formica Fusca ◽  
Indirect Fitness ◽  
Fitness Benefits ◽  
Reproductive Conflicts

Reproductive cooperation confers benefits, but simultaneously creates conflicts among cooperators. Queens in multi-queen colonies of ants share a nest and its resources, but reproductive competition among queens often results in unequal reproduction. Two mutually non-exclusive factors may produce such inequality in reproduction: worker intervention or queen traits. Workers may intervene by favouring some queens over others, owing to either kinship or queen signals. Queens may differ in their intrinsic fecundity at the onset of oviposition or in their timing of the onset of oviposition, leading to their unequal representation in the brood. Here, we test the role of queen kin value (relatedness) to workers, timing of the onset of oviposition and signals of presence by queens in determining the maternity of offspring. We show that queens of the ant Formica fusca gained a significantly higher proportion of sexuals in the brood when ovipositing early, and that the presence of a caged queen resulted in a significant increase in both her share of sexual brood and her overall reproductive share. Moreover, the lower the kin value of the queen, the more the workers invested in their own reproduction by producing males. Our results show that both kinship and breeding phenology influence the outcome of reproductive conflicts, and the balance of direct and indirect fitness benefits in the multi-queen colonies of F. fusca .

scholarly journals IN SILICO MODELING OF THE REDOX METABOLISM IN HUMAN ERYTHROCYTES

2016 ◽  
Vol 1 ◽  
pp. 39-46
Author(s):  
Olga Dotsenko
Keyword(s):  
Redox State ◽  
Physiological State ◽  
Pentose Phosphate ◽  
Human Erythrocytes ◽  
Final Model ◽  
In Silico Modeling ◽  
Long Time ◽  
External Conditions ◽  
The Many ◽  
The Mathematical Model

There was elaborated the mathematical model of erythrocytes metabolism, including glycolysis (Embden-Meyerhof pathway), pentose phosphate pathway, metHb restoration pathway, Н2О2 metabolism reaction. The final model includes 50 reactions and 60 metabolites. Within the model was studied the change of activity of some enzymes and concentrations of metabolites in stationary state, that take part in the processes of utilization of oxygen active forms and restoration of metgemoglobin, depending on amount of exogenous and endogenous Н2О2. There was demonstrated the threshold character of changes of the many studied parameters, that testifies that the cells can be practically in physiological state at the change of external conditions for rather long time. There was carried out an assessment of redox-state of erythrocytes at oxidizing load: was demonstrated the change of EGSSG/2GSH, ENADP+/NADPH and ENAD+/NADH from the concentration of endogenous Н2О2. There was established that in the studied diapason of concentrations of endogenous Н2О2 was observed the high slope of the change of EGSSG/2GSH, that was not observed for ENADP+/NADPH and the other redox-pairs. The results of modeling coincide with existing views on the functioning of enzymes of antioxidant protection in human erythrocytes and testify to the possibility of practical use of the model

Hormonal and Experiential Factors Influencing the Nestbox Oriented Behaviour of Budgerigars (Melopsittacus Undulatus)

Behaviour ◽  
1969 ◽  
Vol 35 (1-2) ◽  
pp. 1-25 ◽  
Author(s):  
Barbara F. Brockway
Keyword(s):  
Prior Experience ◽  
Ovarian Follicle ◽  
Physiological State ◽  
Gonadal Hormones ◽  
Egg Laying ◽  
Nest Building ◽  
Ovarian Activity ◽  
Male Courtship ◽  
Opposite Sex ◽  
Males And Females

AbstractOther workers have shown that gonadal hormones can stimulate avian nest building and that there are species differences concerning the identity of the efficacious hormones. Nest building may be stimulated by estrogenic but not by androgenic material in one species. In another species, the converse is true. Budgerigars do not build nests. Their eggs are laid in tree-cavities. The female performs an easily quantified behaviour that is oriented to her prospective egg-laying site (a nestbox in the laboratory). This nestbox-oriented behaviour (NBOB) consists of remaining within the nestbox for various intervals throughout the day. This occurs daily, and she spends progressively more time within the nestbox as the day of initial oviposition approaches. Thus, NBOB is temporally and situationally related to nest building. A male rarely enters a nestbox unless he is engaging in courtship activities oriented to his mate. This report concerns laboratory studies that were conducted to determine: (1) the effects of different quantities of exogenous testosterone, estradiol and progesterone upon the NBOB of male and female budgerigars when they were individually-caged and unable to see or to hear members of the opposite sex, and (2) the effects of prior breeding experience(s) upon hormonally-induced NBOB. Four experiental types were studied: (V) virgins of either sex which, since fledging, had been visually isolated from the opposite sex and nestboxes; (Ex) males and females which had participated in at least one successful breeding cycle prior to this study; (V1) virgin females which were induced to perform NBOB but to maintain undeveloped ovaries; and (V2) virgin females which were induced to undergo full ovarian development and oviposition in the absence of nestboxes. Both intact and castrated males were studied. Ovarian hormones were given only to castrated males. No ovariectomized females were studied. Birds were injected thrice weekly and observed for 3 weeks. 1) Sexual identity and hormonal factors. Estradiol with or without progesterone stimulated NBOB by V and Ex males and females. The presence or absense of testicular androgens did not induce any male to perform NBOB. Larger (1.0 mg) quantities of testosterone induced females to perform NBOB, but such NBOB was atypically erratic. Testosterone-induced NBOB by females may have been a more direct manifestation of a testosterone-increased ovarian activity; however, the oviducts and ovaries of females receiving either 0.5 mg of 1.0 mg quantities of testosterone were not significantly heavier or larger than those of controls receiving only oil. Progesterone, alone, was just as ineffective as was the oil placebo: neither promoted any significant NBOB by males or females. These findings suggest that NBOB and nest building are not only related in temporal and situational ways, but share a common endocrinological denominator as well. Since NBOB appears to be primarily influenced by increased plasma levels of estrogenic material rather than by decreased levels of androgenic material, the NBOB of burgerigars is similar to the nest building of canaries and ring doves and diametrical to the androgen-stimulated nest building of black-crowned night herons. Estradiol with or without progesterone prompted females but not males to perform advanced phases of NBOB. Also females performed many phases of NBOB sooner than did males. Thus, males seem to be (genetically) less responsive to hormonal stimuli prompting NBOB than are females. 2) Experiential factors. In general, V birds of both sexes began to perform each phase of NBOB later and spent less time in nestbox occupation than did Ex birds receiving identical treatments. A previous study showed that Ex females, stimulated by either visual or vocal male courtship displays performed NBOB sooner than did V females. This prompted me to compare the ovarian follicle sizes and oviductal weights between Ex and V females receiving identical treatments and to examine the hormonally induced NBOB of V1 and V2 females. Since there were no significant differences in the ovarian and oviductal measurements between V and Ex females receiving identical injections, the differential response in the NBOB of V and Ex females does not seem to be solely due to a difference in the development of their reproductive tracts. Accordingly, we cannot say that male courtship more readily promotes NBOB with Ex than with V females because V females require more male stimulation in order to attain a given endogenous hormonal level or physiological state than do Ex females. Indeed prior experience may affect neural thresholds for response to given endogenous hormonal states without altering the response of reproductive organs. Perhaps Ex females are more readily induced to perform NBOB due to some factor involved in previous NBOB or a general familiarity with nestboxes. Data on V1 and V2 females supports this latter hypothesis. The onsets of each phase of NBOB and the amount of nestbox occupation were both potentiated by prior cxperience(s) concerning nestboxes. Prior experience(s) concerning heterosexual interactions or full ovarian activity and oviposition did not significantly affect hormonally induced NBOB.

Vitamin D metabolism: physiological regulation in egg-laying Japanese quail

1976 ◽  
Vol 230 (6) ◽  
pp. 1609-1615 ◽  
Author(s):  
AD Kenny
Keyword(s):  
Japanese Quail ◽  
Vitamin D3 ◽  
Physiological State ◽  
Reproductive Period ◽  
Egg Laying ◽  
Ovulatory Cycle ◽  
Vitamin D Metabolism ◽  
Dihydroxyvitamin D3 ◽  
Enhanced Production ◽  
Egg Shell

Homogenates of kidney removed from reproductivity active female Japanese quail were incubated with tritiated 25-hydroxyvitamin D3, and the metabolites were extracted and identified by chromatographic methods. Kidneys removed from birds with and without an egg in the oviduct revealed that ovulation results in enhanced production of 1, 25-dihydroxyvitamin D3, the active hormonal form of vitamin D3. Further examination of this phenomenon in relation to the ovulatory cycle revealed that 1, 25-dihydroxy-vitamin D3 production is enhanced throughout the 24 h following ovulation. Particularly important is the finding that its synthesis is already enhanced during the first 6 h after ovulation, at a time before any calcification of the egg shell begins. If, following oviposition, no ovulation occurs, 1, 25-dihydroxy-vitamin D3 production decreases rapidly and significantly within the first 6 h following oviposition. This study has revealed for the first time a physiological state, namely the reproductive period in the female bird, in which endogenous control over 1, 25-dihydroxyvitamin D3 production is exhibited without any previous manipulation, dietary or otherwise, of the animals.

scholarly journals Reproductive competition in the bumble-bee Bombus terrestris: do workers advertise sterility?

2009 ◽  
Vol 276 (1660) ◽  
pp. 1295-1304 ◽  
Author(s):  
Etya Amsalem ◽  
Robert Twele ◽  
Wittko Francke ◽  
Abraham Hefetz
Keyword(s):  
Unusual Case ◽  
Bombus Terrestris ◽  
Egg Laying ◽  
Gland Secretion ◽  
Dufour's Gland ◽  
Dufour’S Gland ◽  
Reproductive Competition ◽  
High Ester ◽  
Dufour's Gland Secretion ◽  
Compositional Changes

Reproductive competition in social insects is generally mediated through specific fertility pheromones. By analysing Dufour's gland secretion in queens and workers of Bombus terrestris under varying social conditions, we demonstrate here that the volatile constituents of the secretion exhibit a context-dependent composition. The secretion of egg-laying queens is composed of a series of aliphatic hydrocarbons (alkanes and alkenes), while that of sterile workers contains in addition octyl esters, dominated by octyl hexadecanoate and octyl oleate. These esters disappear in workers with developed ovaries, whether queenright (QR) or queenless (QL), rendering their secretion queen-like. This constitutes an unusual case in which the sterile caste, rather than the fertile one, possesses extra components. Individually isolated (socially deprived) workers developed ovaries successfully, but failed to oviposit, and still possessed the octyl esters. Thus, whereas social interactions are not needed in order to develop ovaries, they appear essential for oviposition and compositional changes in Dufour's gland secretion (ester disappearance). The apparent link between high ester levels and an inability to lay eggs lends credence to the hypothesis that these esters signal functional sterility. We hypothesize that by producing a sterility-specific secretion, workers signal that ‘I am out of the competition’, and therefore are not attacked, either by the queen or by the reproductive workers. This enables proper colony function and brood care, in particular sexual brood, even under the chaotic conditions of the competition phase.

Asymmetries in Physiological State as a Possible Cause of Resident Advantage in Contests

Behaviour ◽  
1998 ◽  
Vol 135 (8) ◽  
pp. 1013-1030 ◽  
Author(s):  
Russell Messing ◽  
Daniel Papaj
Keyword(s):  
Ceratitis Capitata ◽  
Physiological State ◽  
Egg Laying ◽  
Field Cage ◽  
Searching Behaviour ◽  
Relative Age ◽  
State Variable ◽  
Dynamical State ◽  
Host Fruit ◽  
Possible Cause

AbstractAs is common in defense of resources in many animals, contests on host fruit between female Mediterranean fruit flies (Ceratitis capitata) are generally resolved in favour of the resident individual. Here we offer an interpretation of resident advantage in this species which is derived from a dynamical state-variable perspective on behaviour. We first demonstrated the occurrence of residence advantage. In field-cage assays of freely-foraging and freely-interacting females within a tree bearing host coffee berries, the occurrence of two females on a berry almost always resulted in contests. Approximately half of the contests among females on berries resulted in clear winners; resident females won an overwhelming majority of such contests. Contests tended to occur while the resident fly was currently engaged in egg-laying, either boring into the berry with their ovipositor or marking the berry after laying eggs. Non-residents, by contrast, were uniformly engaged in searching behaviour. We next tested the hypothesis that degree of resident advantage is a function of the degree to which a resident is engaged in egg-laying behaviour just prior to the contest. In experimental manipulations of resident status, which female won depended strongly on what residents were doing at the time contests were initiated. If residents were resting and grooming, non-residents (who were uniformly searching) usually won. If residents were laying eggs or marking the fruit after laying eggs, residents usually won. Only when both residents and non-residents were engaged in searching behaviour did the outcome of a contest not depend on resident status. Finally, we tested the hypothesis that contest outcome is related to the dynamical state of the contestants in terms of their relative age. We staged contests between host-deprived females that differed in age by two weeks, manipulating age independently of resident status. Older females won virtually all contests with younger ones regardless of resident status. In a field-cage assay of freely-foraging flies, older females also engaged in significantly more egg-laying activity. Taken together, these results indicate that older females value a fruit more highly than do younger ones, invest more in defense of that resource and therefore win more contests.

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