Wyniki wyszukiwania

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Survival and hazard functions in the population of David's deer [Elaphurus davidianus Milne-Edwards, 1866]

100%

Molinska-Glura M., Szwaczkowski T., Molinski K.

Animal Science Papers and Reports

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2004

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tom 22

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nr 2

Survival and hazard functions supply suitable information concerning changes in the population dynamics, especially in the case of species that are not subjected to artificial selection. One of such species is David’s deer (Elaphurus davidianus Milne-Edwards, 1866) that underwent a dramatic reduction in the population size in the first years of the XX century, but has been subsequently restored from 18 individuals.Population dynamics changes were studied on 1221 David’s deers kept in zoological gardens in the years 1947-2001. Survival and hazard functions were constructed for all individuals according to sex, and separately for those which died in the first year of life, i.e. 14.5% males and 8% females.The hazard function showed similar values for individuals of both sexes in the year 6, 10, 15, 17 and 18 of life. For all males the medians for mortality (hazard function) appeared similar to those for all females. Similar pattern was shown for yearlings. However, between day 40 and 323 shapes of these functions were quite different. Generally, the life span in females was found longer than in males.

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The genetic background of longevity in David's deer [Elaphurus davidianus, Milne Edwards 1866]

84%

Sternicki T., Wolc A., Szwaczkowski T.

Seria Biologiczna. Uniwersytet im. Adama Mickiewicza w Poznaniu

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2005

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tom 72

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Hazard rates for clustered populations of David's deer [Elaphurus davidianus Milne-Edwards, 1866]

67%

Molinska-Glura M., Szwaczkowski T., Molinski K.

Animal Science Papers and Reports

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2008

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tom 26

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nr 2

The objective of the study was to assess the mortality risk of David’s deer associated with climatic conditions by the use of hazard function within clustered populations and according to place of birth. Additionally, the inbreeding level was examined within each cluster. Records were considered of 1192 individuals born in 56 zoological gardens in the years 1947-2000. Censored data (animals which were alive on December 31, 2000) were also included in the analysis. Average lifetime and percentage of dead individuals per zoo were used to determine two-dimensional Euclidean distances.The hazard rates were estimated within derived clusters of zoological gardens. The analysis was performed within sex groups for the following two data sets: all individuals (1), and animals dead In the first year of life (2). In the case of the latter, only three clusters were included. In general, the sizes of clusters appeared different (from two to eighteen zoos). From a geographical perspective these groups are heterogeneous. Generally, the shapes of hazard curves are similar with a clear increasing trend. The differences between groups reflect mainly an inconsistence of time points. The first peak of mortality appears at an early stage of life. The results clearly show the differences in mortality between males and females in all groups (for both sets − 1 and 2). Geographical region showed no significant effect on the survival of David’s deer. It is concluded that life span is determined more by the inbreeding level and zoo management conditions than by the climatic zone.

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Inbreeding effects on lifetime in David's deer [Elaphurus davidianus, Milne Edwards 1866] population

67%

Sternicki T., Szablewski P., Szwaczkowski T.

Journal of Applied Genetics

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2003

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tom 44

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nr 2

Ograniczanie wyników

2 Animal Science Papers and Reports

1 Journal of Applied Genetics

1 Seria Biologiczna. Uniwersytet im. Adama Mickiewicza w Poznaniu

4 Szwaczkowski T.

2 Molinska-Glura M.

2 Molinski K.

2 Sternicki T.

1 Szablewski P.

1 Wolc A.

1 2008

1 2005

1 2004

1 2003

Survival and hazard functions in the population of David's deer [Elaphurus davidianus Milne-Edwards, 1866]

The genetic background of longevity in David's deer [Elaphurus davidianus, Milne Edwards 1866]

Hazard rates for clustered populations of David's deer [Elaphurus davidianus Milne-Edwards, 1866]

Inbreeding effects on lifetime in David's deer [Elaphurus davidianus, Milne Edwards 1866] population