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1

Life span of worker honeybees reared in colonies kept on small-cell combs

100%
Olszewski K., Borsuk G., Paleolog J., Strachecka A.
Medycyna Weterynaryjna
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2014
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tom 70
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nr 12
Between 2011 and 2013, in laboratory cage tests, we compared life spans of bees reared in colonies kept on small-cell combs (cell width of 4.93 mm) that were either treated or untreated against varroatosis, as well as life spans of bees reared in colonies kept on standard-cell combs (cell width of 5.56 mm), both treated and untreated against varroatosis. Maintaining colonies on small-cell combs, combined with the lack of strong parasitic pressure from V. destructor, extended the life span of these bees in comparison with that of bees from standard-cell combs. The keeping of colonies on small-cell combs increased the longevity of bees reared on them and heavily infested by the parasites. Intensive infestation by V. destructor mites shortened the life span of bees, regardless of comb cell width, as confirmed by significant correlation coefficients between the parameters defining the scale of infestation and the life span of bees, while the specifics of the interrelation between the worker life span and the scale of infestation depended on the cell width (small/standard). Hence, comb cell width affects the biology of both the parasite and the host, as well as the relationship between them. Therefore, analysing biological connections between A. mellifera colonies and V. destructor in the context of different comb cell widths seems a very promising direction for research.
2

Some factors influencing the results of the cage tests of a life span and food intake in Apis Mellifera workers

100%
Paleolog J., Borsuk G., Olszewski K.
Annales Universitatis Mariae Curie-Skłodowska. Sectio EE: Zootechnica
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2003
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tom 21
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nr 2
3
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Content available

Fine root lifespan dynamics in four sour cherry (Prunus cerasus) cultivars grown in Central Poland using the minirhizotron technique

84%
Gluszek S., Sas Paszt L., Jadczuk Tobjasz E., Sumorok B.
Dendrobiology
|
2015
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tom 73
Sour cherry (Prunus cerasus L.) is one of the most important fruit crops in Poland. There are many varieties cultivated in orchards, but only a few of them play an important role in commercial production. These few varieties have been the object of numerous studies focused on practical aspects like growth performance, yielding, or resistance to diseases. Recently more belowground research has been carried out in pomological plants using the minirhizotron research allowing to observe roots in short and long term experiments. There have been very few studies concerning root growth dynamics of sour cherry cultivars. Here we studied the influence of four major factors on root growth: the cultivar, root diameter, soil depth, and season on the survivorship of fine roots. We used the minirhizotron technique (MR) to examine fine roots dynamics of four sour cherry cultivars grafted on the Mahaleb rootstock, grown in an experimental orchard in Central Poland. The results revealed that the greatest impact on root survivorship was exerted by root diameter, depth of root formation and the season, whereas cultivars had no obvious influence. The finest roots (with a diameter <0.2 mm) and roots formed at a depth of down to 10 cm below the soil surface had the shortest survivorship. On the other hand, thicker roots (>0.75mm) and roots formed at a depth of more than 50 cm below the soil surface have the longest survivorship. The season of root growth has little impact on root survivorship, but has a big influence on the number of the roots formed. There is no impact of the cultivar on the differences in observed roots survivorship.
4

Life span of needles of Pinus mugo Turra: effect of altitude and species origin

84%
Boratynski A., Jasinska A., Boratynska K., Iszkulo G., Piorkowska M.
Polish Journal of Ecology
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2009
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tom 57
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nr 3
567-572
The needle life span of evergreen coniferous trees is a species-specific trait but can be also affected and modified by environmental conditions. On the basis of field observations of needle life span during three periods in two populations of Pinus mugo in the Tatra Mts (altitude: 1600–1700 m) and Sudety Mts (altitude 830–1420 m), 11 populations from various altitudes we concluded that: 1) within the same population needle life span remained the same over the three periods of observations, 2) needle life span in the Tatra Mts is about 1 year longer than in the Sudety Mts, ranging from 5.5 to 5.9 years and 3) needle life span in the Sudety Mts increases significantly with the altitude of the population. The longer life span of needles in the Tatra Mts may be specific for the population, i.e. it may be due to a different population origin (another Pleistocene centre of the species), and the shorter life span of needles noted in the Sudety Mts may be due to higher soil pollution in this region.
5

Life-span of long and rough coated dachshunds in dependence of their inbreed level and sex

84%
Kosowska B., Strzala T., Moska M., Kujalowicz J., Oryszczak E., Piecyk J., Sawczuk M., Slusarczyk J., Wasilewska K.
Electronic Journal of Polish Agricultural Universities. Series Veterinary Medicine
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2005
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tom 08
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nr 4
6

The influence of vegetation structure on the composition of the seed rain and seedling pool in abandoned Molinion caeruleae meadows

84%
Kostrakiewicz-Gieralt K.
Polish Journal of Ecology
|
2017
|
tom 65
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nr 2
The investigations of the effect of different habitat conditions on the composition of the seed rain and seedling pool were conducted in the years 2014 and 2015 in abandoned patches of Molinion caeruleaedominated by small-stature meadow taxa (patch I), tall-growing grasses (patch II), as well as shrubs and trees (patch III). Observations showed that along the successional gradient the seed rain and seedling pool diminishes. The prevalence of perennials and native taxa in the seed rain and seedling pool occurred in all the study sites. Moreover, in the propagule and seedling pools of all the patches hemicryptophytes and meadow taxa prevailed but their number decreased in successional sites. Also, the abundance of ruderal and grassland taxa decreased gradually, at expense of number of forest species. Zoochorous species prevailed in the seed rain and seedling pool of all patches. Number of hydrohorous species decreased in successional patches, while the abundance of species with other dispersal modes were similar. Irrespective of patch character, the species producing propagules with medium size dominated in the seed rain and seedling pools, whereas a significant decrease of number of small-seeded species was noticed only in the seedling pool. Despite the diminishing of the seed rain and seedling pool along the successional gradient, the gap creation might be a very effective way of active protection of Molinion caeruleae meadows. However, the gap colonisation requires permanent monitoring to avoid further spreading of undesired taxa.
7
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

The impact of age at the first calving on lifetime milk yield, life span and herd life of dairy cows

84%
Kalinska A., Slosarz J., Golebiewski M., Wojcik A., Przysucha T., Kuzinska B.
Annals of Warsaw University of Life Sciences - SGGW. Animal Science
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2019
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tom 58[3]
8

Tiller demography of Festuca pallens Host [Gramineae] in two dry grassland communities

84%
Janisova M.
Polish Journal of Ecology
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2006
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tom 54
|
nr 2
Tiller demography of a perennial caespitose grass Festuca pallens Host was studied on permanent plots in two types of dry grasslands. The field work was done in the Považský Inovec Mts. (Western Carpathians) during 1993–1995. The permanent plot in the Poo badensis-Festucetum pallentis was located on a steep, strongly eroded S-facing slope covered with dolomit outcrops, scree and sparse vegetation (20%) dominated by Festuca pallens. The permanent plot in the Festuco pallentis-Caricetum humilis was located on the even ridge plateau with shallow stony soil and vegetation covering about 70% dominated by Carex humilis and Festuca pallens. The aim was to estimate the basic characteristics of tiller life cycle in Festuca pallens: tillering, flowering, mortality and life span. Tillers of Festuca pallens are exclusively intravaginal with a leaf rosette and polycyclic (can live for more than three years). A proximate maximum life span of orthotropic tiller parts was five or six years. The proportion of flowering tillers in the studied populations varied between the years from 3% to 10%. The mortality of tillers due to flowering represented about 50% of the overall tiller mortality. Flowering was mostly accompanied by an intensive pregenerative tillering. Tillering culminated twice a year – in spring and in autumn. About a quarter of the axillary buds developed into daughter tillers immediately after their formation. The fate of tillers in terms of survival, flowering and daughter tiller production can be predicted by their size. Both components of tiller size – leaf number and leaf length – influenced the fate of tillers although the predictive ability was stronger for leaf number. The two studied populations differed significantly in leaf number, leaf length and the height of inflorescences. These characteristics are supposed to be determined by external habitat conditions. The individual tiller life cycle (survival, life span, daughter tiller production) did not differ between the populations, thus the factors by which it is determined seem to be identical. These results support the idea that the basic processes and structures of tiller ontogeny are internally fixed for each species while external environmental conditions can only induce variability in absolute size.
9

Life history strategies of fish: patterns in growth and lifespan of rudd Scardinius erythrophthalmus (L.) in Europe

67%
Tarkan A. S., Lappalainen J., Nurminen L., Horppila J.
Polish Journal of Ecology
|
2010
|
tom 58
|
nr 1
Variation in life history strategies of rudd Scardinius erythrophthalmus (L.) in Europe was evaluated based on published sources. The growth and lifespan were analysed as the main variables in life strategies of any fish. The results revealed that total length (TL) at age 1 year was correlated with latitude and faster growth during the first growing season leads to a shorter lifespan in Europe. Variation in length at age 1 year was more pronounced in southern (40–46°N: mean TL = 84.6 mm, SD = 27.2, n = 9) than in northern populations (49–61°N: mean TL = 46.4 mm, SD = 4.2, n = 10). Thus, rudd can show different life history strategies in southern populations whereas in northern populations these options are few.
10

Changed gene expression and longevity in honeybees (Apis mellifera) fed with phenylbutyrate- and phenylacetylglutaminate-supplemented diet

67%
Burzynski S. R., Paleolog J., Patii S., Ilkowska-Musial E., Borsuk G., Olszewski K., Chittur S. V., Gupta V., Sarangi R., Strachecka A.
Medycyna Weterynaryjna
|
2013
|
tom 69
|
nr 12
4-4-Phenylbutyrate (PB), present in plants and royal jelly (RJ), plays a vital part in honeybee longevity. Phenylacetylglutaminate (PG) is a metabolite of PB. The aim of this research was to study changes in gene expression in honeybee workers fed with PB+PG-supplemented diet (in 50% sucrose syrup) by gene array and pathway analysis of their brains, and to perform cage longevity studies. The control group received sucrose syrup only. The statistical analysis of microarray results was performed with Genespring and LimmaGUL. Functionally related genes were identified with the help of Gene Ontology in Gostat. A detailed pathway analysis was conducted by importing annotated gene lists to the PathwayArchitect. The most significant results were noted in chromatin remodeling, the TCA cycle, glutathione system (up-regulation), and Notch signaling (down-regulation), which may contribute to increased longevity. These results suggest that PB and PG increase the expression of genes that play an important part in development and life extension. The study of the longevity of caged honeybees consisted in feeding larvae and worker bees with PB+PG-supplemented diet, and comparing them with non-supplemented controls. In three longevity experiments, the bees that were given PB+PG at the larval stage lived longer. This points to a long-term epigenetic effect, which has not been observed in earlier studies.
11
Content available remote

Melatonin and aging: prospects for human treatment

67%
Bubenik G. A., Konturek S. J.
Journal of Physiology and Pharmacology
|
2011
|
tom 62
|
nr 1
Human life span, with or without modern medicine is around 85-95 years. All living creatures have their inner clock that measures their daily (circadian) and their seasonal (circannual) time. These time changes are mediated by the alteration of levels of melatonin, an evolutionary ancient hormone, which is produced in many body tissues, including the pineal gland, retina and the gastrointestinal tract (GIT). Light is blocking the production of melatonin in the pineal gland, darkness is stimulating it. So, the diurnal changes of light intensity of melatonin, provide a "daily clock" and the seasonal changes provide a "seasonal clock". Finally, the reduction of melatonin observed with aging, may indicate the presence of an "age clock". Melatonin is a strong antioxidant (often it is called scavenger of free radicals), which protects the body from the effects of noxious compounds. Therefore it was hypothesized that the reduction of melatonin levels with age contributes to the aging process. So far, the only remedy to extend the life span was a 40% reduction in caloric intake, which prolonged the life in mice, rats, dogs and monkeys by 30-50%. A large group of people imitate these experiments performed on animals, but the results of these experiments will not be known for several decades. How is being hungry prolonging the life span? There is a connection between caloric reduction and melatonin levels in GIT. Several experiments indicate that fasting in animals substantially increased their production of GIT melatonin. Therefore, instead of being permanently hungry, a prolongation of human life could be achieved by a replacement melatonin therapy. A daily intake of melatonin before bed time might achieve the same effect as fasting e.g. an increase of body melatonin levels, which will protect the individual from the ravages of old age. That includes Parkinson's disease and Alzheimer's disease. There is a large group of people taking melatonin daily who believe that melatonin is the "fountain of youth". Those are the subjects which will one day provide an experimental evidence of the efficacy of melatonin.
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