scholarly journals When it is costly to have a caring mother: food limitation erases the benefits of parental care in earwigs

2012 ◽  
Vol 8 (4) ◽  
pp. 547-550 ◽  
Author(s):  
Joël Meunier ◽  
Mathias Kölliker

The aggregation of parents with offspring is generally associated with different forms of care that improve offspring survival at potential costs to parents. Under poor environments, the limited amount of resources available can increase the level of competition among family members and consequently lead to adaptive changes in parental investment. However, it remains unclear as to what extent such changes modify offspring fitness, particularly when offspring can survive without parents such as in the European earwig, Forficula auricularia . Here, we show that under food restriction, earwig maternal presence decreased offspring survival until adulthood by 43 per cent. This effect was independent of sibling competition and was expressed after separation from the female, indicating lasting detrimental effects. The reduced benefits of maternal presence on offspring survival were not associated with higher investment in future reproduction, suggesting a condition-dependent effect of food restriction on mothers and local mother–offspring competition for food. Overall, these findings demonstrate for the first time a long-term negative effect of maternal presence on offspring survival in a species with maternal care, and highlight the importance of food availability in the early evolution of family life.

2011 ◽  
Vol 7 (3) ◽  
pp. 352-354 ◽  
Author(s):  
Flore Mas ◽  
Mathias Kölliker

Solicitation signals by offspring are well known to influence parental behaviour, and it is commonly assumed that this behavioural effect translates into an effect on residual reproduction of parents. However, this equivalence assumption concerning behavioural and reproductive effects caused by offspring signals remains largely untested. Here, we tested the effect of a chemical offspring signal of quality on the relative timing and amount of future reproduction in the European earwig ( Forficula auricularia ). We manipulated the nutritional condition of earwig nymphs and exposed females to their extract, or to solvent as a control. There were no significant main effects of exposure treatment on 2nd clutch production, but exposure to extracts of well-fed nymphs induced predictable timing of the 2nd relative to the 1st clutch. This result demonstrates for the first time that an offspring signal per se , in the absence of any maternal behaviour, affects maternal reproductive timing, possibly through an effect on maternal reproductive physiology.


2021 ◽  
Vol 288 (1950) ◽  
Author(s):  
Jules Dezeure ◽  
Alice Baniel ◽  
Alecia Carter ◽  
Guy Cowlishaw ◽  
Bernard Godelle ◽  
...  

The evolutionary benefits of reproductive seasonality are often measured by a single-fitness component, namely offspring survival. Yet different fitness components may be maximized by different birth timings. This may generate fitness trade-offs that could be critical to understanding variation in reproductive timing across individuals, populations and species. Here, we use long-term demographic and behavioural data from wild chacma baboons ( Papio ursinus ) living in a seasonal environment to test the adaptive significance of seasonal variation in birth frequencies. We identify two distinct optimal birth timings in the annual cycle, located four-month apart, which maximize offspring survival or minimize maternal interbirth intervals (IBIs), by respectively matching the annual food peak with late or early weaning. Observed births are the most frequent between these optima, supporting an adaptive trade-off between current and future reproduction. Furthermore, infants born closer to the optimal timing favouring maternal IBIs (instead of offspring survival) throw more tantrums, a typical manifestation of mother–offspring conflict. Maternal trade-offs over birth timing, which extend into mother–offspring conflict after birth, may commonly occur in long-lived species where development from birth to independence spans multiple seasons. Our findings therefore open new avenues to understanding the evolution of breeding phenology in long-lived animals, including humans.


2018 ◽  
Vol 11 (4) ◽  
pp. 316-320 ◽  
Author(s):  
Ehsan Haghi ◽  
Mahmood Alimohammadi ◽  
Attaollah Shakoori ◽  
Fariba Razeghi ◽  
Parisa Sadighara

Abstract Melamine-ware is widely used around the world. There is a public health concern as regards the safety of melamine when exposed to food. This study was carried out to measure the level of melamine migration in melamine-ware products by HPLC method and the effect of food-type on the level of melamine migration. In food control laboratories in Iran, there is no common method to measure and monitor melamine migration, hence a method using HPLC technique was adopted and validated to solve this problem. The validation results showed the reliability with 94.9% accuracy and 95.3% precision. Furthermore, the limit of detection (LOD) and quantification (LOQ) were 0.145 and 0.435 µg/ml, which for a new method were within acceptable ranges. Melamine migrations from 4 most available melamine wares were measured. Distilled water, 3% acetic acid and 15% ethanol were used as food simulant at 30 °C for 90 min. Although melamine migration occurred in all samples and acidic conditions had a significant effect, the values were not higher than the European standard (30 µg/ml). The study revealed that the HPLC method was valid and could be applied and developed to measure melamine migration. However, precautions should be considered while choosing melamine-ware utensil as long-term exposure to this substance has a negative effect on health, especially on the kidneys.


2002 ◽  
Vol 2002 ◽  
pp. 47-47
Author(s):  
M. Marie ◽  
P.A. Findlay ◽  
L. Thomas ◽  
C.L. Adam

Circulating leptin, the obese gene product secreted by adipocytes, is sensitive to short-term (meals, starvation) and long-term (spontaneous food intake, food restriction) changes in energy balance in sheep (Marie et al 2001). The present study aimed to explore relationships between adiposity, adipose tissue from different sites and blood leptin concentrations in rams kept in long days when adiposity is normally high.


2012 ◽  
Vol 81 (2) ◽  
pp. 113-117 ◽  
Author(s):  
Branislav Gálik ◽  
Daniel Bíro ◽  
Marko Halo ◽  
Miroslav Juráček ◽  
Milan Šimko ◽  
...  

The aim of the study was to analyze the effect of different intakes of macroelements from feed on the mineral blood profile of sport horses. In the experiment which lasted for 12 months (6 months for each of the two periods), 14 sport horses with 2 types of feed rations were monitored. The blood was collected at the beginning of the experiment and every 2 months (three blood collections for each period). Feed rations had a negative effect on Ca (3.40 mmol·l-1 and 3.32 mmol·l-1) and K (3.2 mmol·l-1 and 2.98 mmol·l-1) concentrations in equine serum obtained from the second and third blood collection, respectively. Concentration of P (1.28 mmol·l-1 and 1.20 mmol·l-1) in equine serum obtained from the second and third blood collection, respectively, was higher (P < 0.05) compared to the first blood collection. Concentrations of Mg and Na were in reference intervals. In the 2nd period of experiment, feed rations were adjusted based on individual requirements of the monitored horses; the proportion of the mineral ingredient in the feed rations was lowered. More balanced concentrations of Ca, Mg, Na and K were detected in equine blood serum as a result of lower intake of the minerals from feed; the concentration of P was, except for one case, higher than in the 1st period. We observed a positive effect of individual ration compositions based on the results of blood mineral profile. The study describes for the first time the effect of a high and adequate long-term intake of macroelements on their concentrations in sport horses’ blood serum.


2019 ◽  
pp. 114-133
Author(s):  
G. I. Idrisov ◽  
Y. Yu. Ponomarev

The article shows that depending on the goals pursued by the federal government and the available interbudgetary tools a different design of infrastructure mortgage is preferable. Three variants of such mortgage in Russia are proposed, each of which is better suited for certain types of projects and uses different forms of subsidies. According to our expert assessment the active use of infrastructure mortgage in Russia can increase the average annual GDP growth rate by 0.5 p. p. on the horizon of 5—7 years. In the long run the growth of infrastructure financing through the use of infrastructure mortgage could increase long-term economic growth by 0.9 p. p., which in 20—30 years can add 20—30% of GDP to the economy. However, the change in the structure of budget expenditures in the absence of an increase in the budget deficit and public debt will cause no direct impact on monetary policy. The increase in the deficit and the build-up of public debt will have a negative effect on inflation expectations, which will require monetary tightening for a longer time to stabilize them.


1970 ◽  
Vol 19 (1) ◽  
pp. 89-99
Author(s):  
K. Choudhary ◽  
M. Singh ◽  
M. S. Rathore ◽  
N. S. Shekhawat

This long term study demonstrates for the first time that it is possible to propagate embryogenic Vigna trilobata and to subsequently initiate the differentiation of embryos into complete plantlets. Initiation of callus was possible on 2,4-D. Somatic embryos differentiated on modified MS basal nutrient medium with 1.0 mg/l  of 2,4-D and 0.5 mg/l  of Kn. Sustained cell division resulted in globular and heart shape stages of somatic embryos. Transfer of embryos on to a fresh modified MS basal medium with 0.5 mg/l of Kn and 0.5 mg/l of GA3 helped them to attain maturation and germination. However, the propagation of cells, as well as the differentiation of embryos, were inhibited by a continuous application of these growth regulators. For this reason, a long period on medium lacking these growth regulators was necessary before the differentiation of embryos occurred again. The consequences for improving the propagation of embryogenic cultures in Vigna species are discussed. Key words: Pasture  legume, Vigna trilobata, Globular, Heart shape, somatic embryogenesis D.O.I. 10.3329/ptcb.v19i1.4990 Plant Tissue Cult. & Biotech. 19(1): 89-99, 2009 (June)


2017 ◽  
pp. 34-47
Author(s):  
Hoi Le Quoc ◽  
Nam Pham Xuan ◽  
Tuan Nguyen Anh

The study was targeted at developing a methodology for constructing a macroeconomic performance index at a provincial level for the first time in Vietnam based on 4 groups of measurements: (i) Economic indicators; (ii) oriented economic indicators; (iii) socio-economic indicators; and (iv) economic - social – institutional indicators. Applying the methodology to the 2011 - 2015 empirical data of all provinces in Vietnam, the research shows that the socio-economic development strategy implemented by those provinces did not provide balanced outcomes between growth and social objectives, sustainability and inclusiveness. Many provinces focused on economic growth at the cost of structural change, equality and institutional transformation. In contrast, many provinces were successful in improving equality but not growth. Those facts threaten the long-term development objectives of the provinces.


1985 ◽  
Vol 110 (3) ◽  
pp. 329-337 ◽  
Author(s):  
G. A. Schuiling ◽  
H. Moes ◽  
T. R. Koiter

Abstract. The effect of pretreatment in vivo with oestradiol benzoate on in vitro secretion of LH and FSH was studied in long-term ovariectomized (OVX) rats both at the end of a 5-day continuous in vivo pretreatment with LRH and 4-days after cessation of such LRH pretreatment. Rats were on day 0 sc implanted with osmotic minipumps which released LRH at the rate of 250 ng/h. Control rats were implanted with a piece of silicone elastomer with the dimensions of a minipump. On days 2 and 4 the rats were injected with either 3 μg EB or with oil. On day 5 part of the rats were decapitated and the in vitro autonomous (i.e. non-LRH-stimulated) and 'supra-maximally' LRHstimulated release of LH and FSH was studied using a perifusion system. From other rats the minipumps were removed on day 5 and perifusion was performed on day 9. On the 5th day of the in vivo LRH pretreatment the pituitary LH/FSH stores were partially depleted; the pituitaries of the EB-treated rats more so than those of the oil-injected rats. EB alone had no significant effect on the content of the pituitary LH- and FSH stores. On day 9, i.e. 4 days after removal of the minipumps, the pituitary LH and FSH contents had increased in both the oil- and the EB injected rats, but had not yet recovered to control values. In rats not subjected to the 5-days pretreatment with LRH EB had a positive effect on the supra-maximally LRH-stimulated secretion of LH and FSH as well as on the non-stimulated secretion of LH. EB had no effect on the non-stimulated secretion of FSH. After 5 days of in vivo pretreatment with LRH only, the in vitro non-stimulated and supra-maximally LRH-stimulated secretion of both LH and FSH were strongly impaired, the effect correlating well with the LRH-induced depletion of the pituitary LH/FSH stores. In such LRH-pretreated rats EB had on day 5 a negative effect on the (already depressed) LRH-stimulated secretion of LH (not on that of FSH). EB had no effect on the non-stimulated LH/FSH secretion. It could be demonstrated that the negative effect of the combined LRH/EB pretreatment was mainly due to the depressing effect of this treatment on the pituitary LH and FSH stores: the effect of oestradiol on the pituitary LRH-responsiveness (release as related to pituitary gonadotrophin content) remained positive. In LRH-pretreated rats, however, this positive effect of EB was smaller than in rats not pretreated with LRH. Four days after removal of the minipumps there was again a positive effect of EB on the LRH-stimulated secretion of LH and FSH as well as on the non-stimulated secretion of LH. The positive effect of EB on the pituitary LRH-responsiveness was as strong as in rats which had not been exposed to exogenous LRH. The non-stimulated secretion of FSH was again not affected by EB. The results demonstrate that the effect of EB on the oestrogen-sensitive components of gonadotrophin secretion consists of two components: an effect on the pituitary LRH-responsiveness proper, and an effect on the pituitary LH/FSH stores. The magnitude of the effect of EB on the LRH-responsiveness is LRH dependent: it is very weak (almost zero) in LRH-pretreated rats, but strong in rats not exposed to LRH as well as in rats of which the LRH-pretreatment was stopped 4 days previously. Similarly, the effect of EB on the pituitary LH and FSH stores is LRH-dependent: in the absence of LRH, EB has no influence on the contents of these stores, but EB can potentiate the depleting effect of LRH on the LH/FSH-stores. Also this effect disappear after cessation of the LRH-pretreatment.


Author(s):  
O. D. Golyaeva ◽  
O. V. Kurashev ◽  
S. D. Knyazev ◽  
А. Yu. Bakhotskaya

The main goal of the scientific institution was and remains to improve the assortment of fruit and berry crops for the development of domestic horticulture. Black currant breeding at VNIISPK was started by A.F Tamarova and continued by the doctor of agricultural Sciences T.P.Ogoltsova and doctor of agricultural Sciences S.D. Knyazev. A long-term breeding program has been developed. The main goals of the program are to create black currant cultivars with continuous resistance to diseases, first of all powdery mildew, as wells resistance to pests, i.e. bud mite. As a result of the long-term work, over 40 black currant cultivars have been developed, 14 of them are zoned. Red currant breeding was led by the candidate of agricultural Sciences L.V. Bayanova; since 2001 the work has been continued by the candidate of agricultural Sciences O.D. Golyaeva. ‘Heinemanns Rote Spӓtlese’, the descendant of R. multiflorum Kit., was involved in the red currant breeding for the first time in Russia. On its genetic basis, a series of late maturing cultivars with long and dense racemes was created. At the Institute, in total 21cultivars of red currants have been developed, 13 of them are zoned. At present, red currant cultivars make up 25.5% of the zoned assortment in Russia. The first research on gooseberries was stated by V.P. Semakin and A.F Tamarova; since 1992 the systematic gooseberry breeding has been carried out by the candidate of agricultural Sciences O.V. Kurashev. On the basis of Grossularia robusta, we have created gooseberry forms that are resistant to powdery mildew and leaf spots. These forms are highly productive, weakly thorned, having bush habit suitable for mechanized harvest. The result of breeding activities was the transfer of 6 gooseberry cultivars to State agricultural testing: ‘Solnechny Zaychik’, ‘Nekrasovsky’, ‘Yupiter’, ‘Zemlianichny’, ‘Moryachok’ and ‘Discovery’.


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