Wyniki wyszukiwania - AGRO

1

Fecundity of asp Aspius aspius [L., 1758] from Miedzyodrze waters

100%

Kompowski A., Neja Z.

Bulletin of the Sea Fisheries Institute

|

2004

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nr 3

2

Fecundity of blue whiting [Micromesistius australis Norman, 1937] from the Falkland fishing grounds in the years 1983, 1984 and 1986

100%

Trella K.

Bulletin of the Sea Fisheries Institute

|

1998

|

nr 2

3

Reproductive life history of ocelots Leopardus pardalis in southern Texas

86%

Laack L. L., Tewes M. E., Haines A. M., Rappole J. H.

Acta Theriologica

|

2005

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tom 50

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nr 4

505-514

The ocelotLeopardus pardalis Linnaeus, 1758 is an endangered felid in the United States currently restricted to southern Texas. The objectives of our study were to obtain data on ocelot parturition dates, fecundity, sex ratios, den characteristics, and first year survival, all of which are critical in development of population viability models. Sixteen parturition events were recorded ranging from mid-April to late December for 12 wild ocelots. Cumulatively, litters consisted of 1 or 2 kittens (¯ = 1.2 ± 0.44 SD). Cumulative sex ratio was 1∶2.5 (male:female); however, there was no significant difference between the observed sex ratio and a 1∶1 sex ratio. Ten den sites were in close proximity (≤ 10 m) to dense thornshrub. Adult female ocelots used 2 to 4 den sites for each litter with distance between consecutively occupied dens ranging from 110 to 280 m (¯ = 158 m ± 93 SD). An estimated annual survival for ocelots 0 to 1 year of age was 0.68. Evidence suggests that ocelots in the wild may breed more frequently than had been previously hypothesized.

4

Reduced [14C]-methionine uptake and fecundity in Schistosoma mansoni females treated with recombinant tumor necrosis factor alpha in vitro

86%

Haseeb M. A., Agrawal R., Fried B.

Acta Parasitologica

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2017

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tom 62

|

nr 1

5

Fecundity of vendace, Coregonus albula (L.), from several lakes in Western Pomerania

86%

Czerniejewski P., Wawrzyniak W.

Archives of Polish Fisheries

|

2008

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tom 16

|

nr 2

The aim of the study was to determine individual absolute and relative fecundity in vendace, Coregonus albula (L.), populations from four Western Pomeranian lakes that differ morphometrically and trophically. The highest mean total length and individual weight were recorded in the fish from the mesotrophic lakes Ińsko (229.1 mm and 106.6 g, respectively) and Miedwie (228.1 mm and 105.1 g, respectively). The highest individual absolute fecundity in particular age groups as well as individual relative fecundity were noted in the fish from Lake Miedwie (6635-24620 eggs per female and 10756-11609 eggs per 100 g female body weight, respectively), while the lowest values of these parameters were confirmed in fish from Lake Glinna (4782-6087 eggs per female and 6406-6953 eggs per 100 g female body weight). A high, statistically significant correlation between absolute fecundity and total fish length and a slightly lower correlation between absolute fecundity and fish age were noted in all of the populations studied.

6

Variation in the fecundity of roe deer in Britain: effects of age and body weight

86%

Hewison A. J. M.

Acta Theriologica

|

1996

|

tom 41

|

nr 2

This paper investigates variation in female fecundity in relation to effects of age and body weight within and between 15 populations of roe deer Capreolus capreolus (Linnaeus, 1758) in Britain. Analyses were based on carcass material and fecundity was assessed from the presence/absence and number of fertilised ovulations (.corpora lutea) and implanted foetuses. A significant proportion (> 10%) of does ovulated in their first year in some populations, but such precocious reproductive activity rarely resulted in successful implantation of a foetus. Generally, the majority of yearling does (in their second year) conceived successfully, but average potential litter size was lower than among older animals. There was no consistent age-related variation in fecundity among does older than 2 years. Differences in fecundity between age and body weight classes suggest weight thresholds may exist for the onset of puberty and for successful conception as an adult. Fecundity of adults and yearlings was highly variable between populations and in some populations was considerably lower than previously reported for this species. Although differences between populations were correlated with differences in body weight, this relationship was insufficient to explain the wide variation in fecundity across Britain, suggesting fecundity body weight thresholds will be defined independently in separate populations.

7

The fecundity and gonad development cycle of the round goby [Neogobius melanostomus Pallas 1811] from the Gulf of Gdansk

86%

Tomczak M. T., Sapota M. R.

Oceanological and Hydrobiological Studies

|

2006

|

tom 35

|

nr 4

8

Fecundity of cod [Gadus morhua callarias L.] in the Southern Baltic in the late 1990s

86%

Kosior M., Trella K., Jaworski A.

Acta Ichthyologica et Piscatoria

|

2001

|

tom 31

|

nr 2

The fecundity of cod from the southern Baltic Sea in the late 1990s was estimated from 461 pairs of ovaries at the maturity stage IV (according to Maier′s scale). Number of eggs per female was estimated for different length, weight, and age classes of fish obtained from the ICES subdivisions: 25 (Bornholm Deep) and 26 (Gdańsk Deep). Absolute fecundity in relation to body length and age, as well as relative fecundity, showed no differences between the two subdivisions, whereas absolute fecundity in relation to body weight was slightly higher in females from the Gdańsk Deep. Absolute fecundity in relation to age showed a high variability, particularly among age classes 5 and older. Absolute fecundity of cod in the southern Baltic has increased slightly over the past four decades. Length at first maturity, i.e. length at which 50 % of females are mature, was estimated to be 40.2 cm for females from the Gdańsk Deep.

9

The influence of shoot harvesting on the size and fecundity of Convallaria majalis L.

86%

Kosinski I.

Acta Societatis Botanicorum Poloniae

|

2001

|

tom 70

|

nr 4

10

Fecundity of walleye pollock [Theragra chalcogramma Pallas] from the Southwest region of Kamchatka [Sea of Okhotsk]

86%

Trella K.

Bulletin of the Sea Fisheries Institute

|

2002

|

nr 1

11

No relationship between fecundity and annual reproductive rate in bony fish

86%

Froese R., Luna S.

Acta Ichthyologica et Piscatoria

|

2004

|

tom 34

|

nr 1

Background. There is still a widespread notion that bony fishes with high fecundities are more productive and therefore more resistant to overexploitation. The purpose of this study was to formally explore the relationship between fecundity and reproductive success expressed as maximum annual reproductive rate, i.e. the number of new spawners produced by existing spawners at low population densities. Materials and Methods. We used maximum annual reproductive rate from a recent study covering 49 species of bony fish; we used fecundity estimates from the published literature. Results. We found no significant relationship between fecundity (ranging from 368 to 10 million eggs) and maximum annual reproductive rate (ranging from 0.4 to 13.5 replacement spawners). Conclusion. Fecundity in oviparous bony fish without parental care has no relation with reproductive success. Apparently high fecundity in bony fish has evolved to counter-balance pre-adult mortality, as indicated by the fact that variance in fecundity is 3 orders of magnitude larger than variance in annual reproductive rate.

12

Production performance of ewes in the Podlasie Region

86%

Niedziolka R., Kaluza H., Pieniak-Lendzion K., Fedorczuk D.

Natural Sciences

|

1999

|

tom 02

13

Fecundity of vendace [ Coregonus albula ] in relation to year-class variations in Lake Pyhajarvi, SW-Finland

86%

Sarvala J., Helminen H., Hirvonen A.

Polskie Archiwum Hydrobiologii

|

1992

|

tom 39

|

nr 3-4

14

Influence of selected factors on fecundity in chinchilla [Chinchilla velligera] females

86%

Szatkowska I., Sulik M.

Zeszyty Naukowe. Przegląd Hodowlany

|

1996

|

tom 27

15

Fecundity and egg size in sea trout (Salmo trutta m. trutta L.) in pond conditions

72%

Debowski P., Dobosz S., Grudniewska J., Kuzminski H.

Archives of Polish Fisheries

|

2005

|

tom 13

|

nr 2

During a five-year period, the fecundity and egg size of individual Vistula sea trout marked with PIT tags were studied. The dependencies between fish length, age and the number of times the fish had spawned and its fecundity and egg size were analyzed. Both fecundity and egg size increased as fish length increased. However, after taking into consideration fish growth, fecundity decreased slightly with age while egg size increased. These two traits were mutually inversely correlated. After taking into consideration differences in length, fish that were spawning for the first time were less fecund than their peers at a similar egg size.

16

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Biometry and reproductive biology of Pseudonereis anomala Gravier 1901 (Polychaeta: Nereididae) on the Alexandria coast, Egypt

72%

Hamdy R., Dorgham M. M., El-Rashidy H. H., Atta M. M.

Oceanologia

|

2014

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tom 56

|

nr 1

17

Effects of eutrophication on vendace, Coregonus albula (L.). II. Biological characteristics of vendace from selected lakes in Wielkopolska

72%

Fiszer M., Przybyl A., Andrzejewski W., Mazurkiewicz J., Golski J., Przybylska K., Runowski S.

Archives of Polish Fisheries

|

2012

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tom 20

|

nr 2

18

On some problems of reproduction of ruff, Gymnocephalus cernuus (L., 1758) in the Lake Dabie

72%

Neja Z.

Acta Ichthyologica et Piscatoria

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1988

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tom 18

|

nr 2

19

Plasticity in dynamics and hygrochastic persistence in Anastatica hierochuntica (Brassicaceae) populations under simulated rainfall treatments

72%

Hegazy A. K., Kabiel H. F., Alatar A. A., Lovett-Doust J.

Polish Journal of Ecology

|

2013

|

tom 61

|

nr 3

Anastatica hierochuntica is a monocarpic desert annual whose dry skeletons, enclosing mature fruits, often persist for a number of years. The aerial seed bank in these hygrochastic ‘resurrection plants’ therefore persists too. Life tables and fecundity schedules were constructed for A. hierochuntica populations raised under four water treatments, equivalent to 100, 200, 500 and 1000 mm rainfall. Seedling survivorship showed a Deevey type III curve for 100 mm, and a type II curve for 200 mm, while 500 and 1000 mm treatments produced Deevey type I curves. Fewer seeds germinated and seedling survivorship was lower in the low water treatments. The stage-specific mortality rate reached 0.75 under the 100 mm treatment in the seed germination stage, compared to 0.08 under the 1000 mm treatment. Increased water availability resulted in greater plant growth and reproductive output, in terms of both number of seeds per individual and reproductive value. In field studies, aerial seed banks of small plant sizeclasses (from 1 to 32 cm³) were depleted within 3-to-7 years. For the large size-classes, > 32 cm³, only a portion (79.7-44.4%) of the seeds produced were dispersed during the observational experiment (the rest remaining within the tumbleweed ball, available for subsequent germination). The projected seed bank life-time for populations raised under different water treatments increased more than fivefold (from 3 to 17 years) for the 100 mm compared to the 1000 mm rainfall treatments. Local persistence of populations was thus likely to be reduced by water stress. Populations of A. hierochuntica characterized by weak plant growth and a preponderance of small size-classes will be more vulnerable to extinction due to their low reproductive output and reduced aerial seed bank reserve.

20

Morphometrics, fecundity, density, and feeding intensity of the spinycheek crayfish, Orconectes limosus (Raf.) in natural conditions

72%

Chybowski L.

Archives of Polish Fisheries

|

2007

|

tom 15

|

nr 3

The subject of the study was three populations of spinycheek crayfish, Orconectes limosus (Raf.) from lakes Staw Płociczno, Dgał Wielki, and Hańcza. The aspects of the spinycheek crayfish studied were the morphometric characters of females and males, individual absolute fecundity, sex ratio, size structure, density, biomass, and feeding intensity in an annual cycle. It was determined that the body proportions of males in forms I and II differed significantly, while the body proportions of female spinycheek crayfish were similar to those of form II males but different from the body proportions of form I males. The crayfish investigated in the current study had a lower individual absolute fecundity than did spinycheek crayfish of the same body weights from other Polish basins. The crayfish daily food ration exhibited a very strong relationship with the stomach fullness index and water temperature. The empirical formula of this relationship (ln Rd P = 0.397 + 0.094 t + 0.614 ln If) permitted estimating the daily food ration. The crayfish fed most intensely from the May to October period, during which they consumed in excess of 80% of their annual ration. The primary dietary component of the spinycheek crayfish was plant matter. Annually, the crayfish population consumed barely 0.27% of the wet weight of the aquatic vegetation in its range of occurrence.

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