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1

Variation of heterophil-to-lymphocyte ratio in the Great Tit Parus major - a review

100%
Skwarska J.
Acta Ornithologica
|
2018
|
tom 53
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nr 2
Permanent changes in the surrounding environment cause long-term stress in birds, which, when lasting days or weeks, affects the activity of the immune system and increases susceptibility to diseases, leading to changes in the levels of haematological parameters. The heterophil-to-lymphocyte ratio (H:L-ratio) is generally considered an independent and robust indicator of stress level in birds. This parameter allows in a simple way to evaluate activity of the immune system and individual health state of adult and nestling birds. It also enables assessing a body response to short- and long-term stress induced by, among others, the surrounding environment, social stress, blood parasites or a greater energy expenditure of females during breeding. Under conditions of field work the determination of the H:L- ratio is not difficult because what is only needed to conduct a blood smear test is a drop of blood that can be easily obtained even from birds of a small body mass. Moreover, an increase in the H:L-ratio is observed after about an hour from the moment of catching a bird contrary to other measurements like the determination of a baseline level of corticosterone. In this article available literature that discusses the impact of various factors on the H:L-ratio in the Great Tit as a species of 'fast-paced' life is reviewed. In adult and nestling birds the H:L-ratio is influenced by various factors — ecological and ecophysiological ones. In some cases the same factor, e.g. brood size manipulation or a type of habitat, can significantly influence the level of the discussed stress indicator as well as it may not show any impact at all. While interpreting the H:L-ratio one must take into account an impact of various ecological and ecophysiological factors on health state, such as habitat, phase of the annual cycle, differences between brood attempts, sex, age as well as on relations with other indicators of condition e.g. body mass or total blood haemoglobin concentration.
2

Proporcja liczby heterofili do limfocytów jako wskaźnik stresu u ptaków

100%
Skwarska J.
Ornis Polonica
|
2012
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tom 53
|
nr 3
3
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Influence of importin α/β and exportin 1 on equine herpesvirus type 1 (EHV-1) replication in primary murine neurons

45%
Slonska A., Cymerys J., Skwarska J., Golke A., Banbura M. W.
Polish Journal of Veterinary Sciences
|
2013
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tom 16
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nr 4
Viruses replicating in the nucleus need to cross the nuclear membrane barrier during infection, therefore disruption of specific nuclear transport pathways is crucial for their replication cycle. In the present study we have investigated the influence of nucleo-cytoplasmic transport inhibitors – ivermectin and leptomycin B, on EHV-1 replication in primary murine neurons. Obtained results suggest that the examined proteins – exportin 1 and importin α/β may participate, but are not required, during EHV-1 infection. Based on these results, it can be assumed that EHV-1 is able to use other receptors for nucleo-cytoplasmic transport.
4

Egg size variation and breeding characteristics of the Black-winged Stilt Himantopus himantopus in a Saharan oasis

45%
Adamou A.-E., Kouidri M., Chabi Y., Skwarska J., Banbura J.
Acta Ornithologica
|
2009
|
tom 44
|
nr 1
Different aspects of the breeding biology of the Black-winged Shit were studied in a natural oasis wetland area in the Sahara Desert, the Chott of Aïn El Beïda, near Ouargla, E Algeria in 2004-2007. In this wetland the water level is independent of rainfall and Stilts start egg laying when average daily temperature increases to ca. 15°C, mostly in April-May, with no significant differences between years. Complete clutches usually consist of 4 eggs but 3 egg clutches happen with low frequency (2.9-5.6%). Egg size traits (mass, length, breadth and volume) tended to decrease from 2004 to 2007, probably due to deteriorating hydrological conditions of the wetland. Within-clutch variability showed both significant repeatability and laying-sequence-dependent differences among eggs, with the final egg being smaller than the clutch mean value. We found that all egg traits studied showed a negative correlation with the date of laying, which seems to be a phenomenon analogous to the seasonal decrease in clutch size, typical of birds with more variable clutch sizes. Hatching tended to be asynchronous, with average clutch hatching time being 1.84 days. The small final egg and hatching asynchrony are typical components of the adaptive brood reduction, the phenomenon not being recorded so far and remaining for future studies on the Black-winged Stilt. These are the first published data on breeding characteristics for any N African population of the Black-winged stilt.
5

Effects of brood size manipulation on physiological condition of nestling Blue Tits Cyanistes caeruleus

39%
Banbura J., Skwarska J., Kalinski A., Wawrzyniak J., Slomczynski R., Banbura M., Zielinski P.
Acta Ornithologica
|
2008
|
tom 43
|
nr 2
129-138
Producing high quality offspring of good physiological performance, able to survive to independence and, then, to reproductive maturity is a major component of life history strategies. The ability of nestling altricial birds to develop a good physiological condition depends to a large extent on the amount and quality of food provided by parents, as well as other aspects of parental care. We hypothesized that experimental changes to the original brood size should affect both parental Blue Tits and their offspring, resulting in corresponding changes in the body condition of the nestlings. Over two breeding seasons, using two habitat sites, we conducted an experiment with two manipulative treatments applied to broods of three-day-old nestlings — the reduction or enlargement of broods by three nestlings, and one non-manipulative control treatment. Our aim was to test whether the experiment would affect a number of different measures of nestling condition: blood concentrations of hemoglobin and glucose, heterophil-to-lymphocyte ratio and morphometric condition index, all being analyzed when the nestlings were 13 days old. We found no effect in the case of hemoglobin, despite the fact that it had previously been shown to be sensitive to large-scale differences in trophic conditions between habitats and years and to the experimental removal of nest parasites. All the remaining variables, i.e. heterophil-to-lymphocyte ratio, glucose concentration and morphometric condition index, responded to the experimental treatments, showing different but reasonable patterns of variation. We suggest that an experimental increase in brood size definitely hinders the development of nestling physiological condition, but even an experimental reduction of broods can affect some physiological indicators (glucose), probably because of readjustments in the feeding rate.
6

Relationships between nestling hemoglobin concentration and brood performance until fledging in Great Tits Parus major and Blue Tits Cyanistes caeruleus

33%
Kalinski A., Banbura M., Gladalski M., Markowski M., Skwarska J., Wawrzyniak J., Zielinski P., Banbura J.
Acta Ornithologica
|
2017
|
tom 52
|
nr 2
7

Body condition parameters of nestling Great Tits Parus major in relation to experimental food supplementation

33%
Banbura J., Banbura M., Gladalski M., Kalinski A., Markowski M., Michalski M., Nadolski J., Skwarska J., Zielinski P.
Acta Ornithologica
|
2011
|
tom 46
|
nr 2
Amount of food supplied to nestlings by their parents is considered to affect the development of nestling physiological condition. In this study we supplied parental Great Tits Parus major with extra food, larvae of Tenebrio molitor, put into feeders close to nest-boxes, assuming that this should facilitate parental care and, as a consequence, nestling nutrition. The following nestling characteristics measured 13 days after hatching were analysed: body mass, haematocrit, blood concentrations of haemoglobin, glucose and triglycerides, heterophil-to-lymphocyte ratio (H/L), and patagium swelling after PHA injection. Nestlings from extra food broods were significantly heavier than control ones. They also had lower H/L, which indicated lower stress. No other variable was significantly affected by the experiment. Possibly, the rainy weather and non-restrictive natural trophic conditions during the experiment caused weakening of the net benefits from extra food.
8

Variation in egg sizes of Pied Flycatchers Ficedula hypoleuca in central Poland: a long-term decreasing trend

33%
Skwarska J., Kalinski A., Wawrzyniak J., Banbura M., Gladalski M., Markowski M., Zielinski P., Banbura A., Banbura J.
Acta Ornithologica
|
2015
|
tom 50
|
nr 1
9

Differences in the breeding success of Blue Tits Cyanistes caeruleus between a forest and an urban area: a long-term study

33%
Gladalski M., Banbura M., Kalinski A., Markowski M., Skwarska J., Wawrzyniak J., Zielinski P., Czyzewska I., Banbura J.
Acta Ornithologica
|
2017
|
tom 52
|
nr 1
10

Long-term variation in laying date and clutch size of Pied Flycatchers Ficedula hypoleuca in Central Poland

33%
Skwarska J., Kalinski A., Wawrzyniak J., Markowski M., Mikus W., Banbura M., Gladalski M., Zielinski P., Banbura J.
Polish Journal of Ecology
|
2012
|
tom 60
|
nr 1
Long-term annual variation in the timing of egg laying, clutch size and relationship between clutch size and the progress of the season was analysed for the Pied Flycatcher Ficedula hypoleuca nesting in a mature deciduous woodland in central Poland in 2002–2010. The earliest mean egg laying date was 8 May (2005) and the latest 18 May (2008), resulting in the maximum difference of 10 days between averages for years. No long- term trend was found. The total average of annual mean laying dates was 12 May. For all nine years the average of annual mean clutch sizes was 6.54 ± 0.28 (SE) eggs; for individual seasons mean clutch size ranged from 6.0 to 7.1 eggs but differences among years were not significant. Clutch size clearly tended to decline with the progress of the breeding season within years, with some variation between years; correlation for pooled standardized data was –0.49. This supports the idea that in long-distance single-brooded passerine birds clutch size should decrease with the course of the breeding season due to progressively deteriorating food conditions.
11

Parallel variation in haemoglobin concentration in nestling-rearing Blue Tits Cyanistes caeruleus and Great Tits Parus major

33%
Kalinski A., Banbura M., Skwarska J., Wawrzyniak J., Zielinski P., Gladalski M., Markowski M., Banbura J.
Acta Ornithologica
|
2012
|
tom 47
|
nr 2
High metabolic rates of birds demand an efficient oxygen transport system; this is ultimately based on the oxygen carrying capacity of haemoglobin. Therefore patterns of variation in blood haemoglobin content of wild birds are an important aspect of functional ecology. In this paper we report results concerning variation in haemoglobin concentration in the blood of adult Blue Tits Cyanistes caeruleus and Great Tits Parus major during the nestling rearing period (days 7-15 of nestlings life) of first broods in central Poland in 2003-2009. The most important findings of this study are: (i) average haemoglobin concentration in blood differs between Blue Tits and Great Tits, with higher values in Blue Tits; (ii) males differ from females in both these species, with higher values in females, and (iii) there is also significant variation among years, with parallel tendencies for both species. We explain the patterns of haemoglobin content variation in adult tits by differences in metabolic demands for oxygen transported by blood. The demands are higher for the smaller-bodied species (Blue Tits), heavier working sex (females) and in years with worse physical and trophic conditions, though only non-significant relationships with weather conditions (temperature and rainfall) or food availability (measured by frassfall) were found during our long-term study.
12

Egg size variation in Blue Tits Cyanistes caeruleus and Great Tits Parus major in relation to habitat differences in snail abundance

33%
Banbura M., Sulikowska-Drozd A., Kalinski A., Skwarska J., Wawrzyniak J., Kruk A., Zielinski P., Banbura J.
Acta Ornithologica
|
2010
|
tom 45
|
nr 2
13

Long-term changes in population density of nest-box breeding Great Tits and Blue Tits in two contrasting habitats in Central Poland

33%
Gladalski M., Wawrzyniak J., Banbura M., Kalinski A., Markowski M., Skwarska J., Zielinski P., Banbura J.
Polish Journal of Ecology
|
2016
|
tom 64
|
nr 3
Urbanization affects the ecological and behavioral traits of various species of animals, including birds.We present results concerning long-term fluctuations in breeding densities of nest-box populations of the Blue Tit Cyanistes caeruleus and the Great Tit Parus major in two, structurally and floristically contrasting types of habitat (an urban parkland and a rich deciduous forest) located 10 km apart, in central Poland. This study was conducted in 1999–2012 in the parkland site and in 2002–2012 in the forest site. We found a strong correlation of year-to-year changes in breeding densities of Great Tits between the parkland site and the forest site and a lack of such a correlation in Blue Tits. Breeding densities of Great Tits were much higher in the parkland than in the forest area every year during the study period. Annual changes in breeding densities were not correlated between the species studied. The North Atlantic Oscillation Index (NAO-winter index) tended to influence the density dynamics of the two bird species in the forest area but not in the parkland area.
14

Consequences of experimental changes in the rearing conditions of Blue Tit Cyanistes caeruleus and Great Tit Parus major nestlings

27%
Banbura J., Banbura M., Gladalski M., Kalinski A., Marciniak B., Markowski M., Michalski M., Nadolski J., Skwarska J., Wawrzyniak J., Zielinski P.
Acta Ornithologica
|
2013
|
tom 48
|
nr 2
Physiological functions of growing nestlings are thought to be traded-off in relation to rearing conditions, with the resulting physiological state of fledglings having important long-lasting consequences for their fitness. By manipulating brood size up and down, and, separately, by supplying additional food (mealworms — larvae of Tenebrio molitor) we tested if alterations of the rearing conditions would influence nestling performance in Blue Tits Cyanistes caeruleus and Great Tits Parus major. Brood size manipulation affected body mass, heterophil-to-lymphocyte ratio (H:L) and fledging probability in both species and the level of triglycerides in nestling Great Tits. Extra food supply influenced only fledging probability, with no other effect on indicators of nestling performance. An effect on nestling body mass and a lack of effect on cell-mediated immune response in the brood-size experiment suggest that nestlings in enlarged broods sacrificed growth to maintain immunity. In general, effects of both types of experiments were probably to some extent masked by specific character of the study site — an urban parkland with high human-induced disturbance.
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