Analýza produkčního věku holštýnských krav v České republice

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00027014%3A_____%2F04%3A00009946" target="_blank" >RIV/00027014:_____/04:00009946 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Analysis of length of productive life in Holstein cattle in Czech Republic

Popis výsledku v původním jazyce

An analysis of productive life in Holstein cattle in Czech Republic was performed using programs package Survival Kit, based on Cox regression. Data included 477 669 cows. The length of productive life (LPL) was observed between years of first calving 1990 and 2004. 15 % of cows were censored. The risk of being culled was defined as product of a baseline hazard function and a function of explanatory variables. The model included one time-dependent effect, a effect of interaction of lactation number andstage of lactation and three time-independent effects, age at first calving, year of birth and sire. The model explained 16 % of LPL variability. The highest risk of being culled was found for the first lactation and at the beginning of lactation and atthe end of the lactation. Generally, the hazard decreased with parity. The cows older at first calving had higher risk of being culled. The risk of being culled vary with years of birth. The effect of the sire plays a role in the question o

Název v anglickém jazyce

Analysis of length of productive life in Holstein cattle in Czech Republic

Popis výsledku anglicky

An analysis of productive life in Holstein cattle in Czech Republic was performed using programs package Survival Kit, based on Cox regression. Data included 477 669 cows. The length of productive life (LPL) was observed between years of first calving 1990 and 2004. 15 % of cows were censored. The risk of being culled was defined as product of a baseline hazard function and a function of explanatory variables. The model included one time-dependent effect, a effect of interaction of lactation number andstage of lactation and three time-independent effects, age at first calving, year of birth and sire. The model explained 16 % of LPL variability. The highest risk of being culled was found for the first lactation and at the beginning of lactation and atthe end of the lactation. Generally, the hazard decreased with parity. The cows older at first calving had higher risk of being culled. The risk of being culled vary with years of birth. The effect of the sire plays a role in the question o

Druh

D - Stať ve sborníku

CEP obor

GI - Šlechtění a plemenářství hospodářských zvířat

OECD FORD obor

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Projekt

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Návaznosti

Z - Vyzkumny zamer (s odkazem do CEZ)

Rok uplatnění

2004

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

Sustain Life Secure Survival II

ISBN

80-213-1197-5

ISSN

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e-ISSN

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Počet stran výsledku

5

Strana od-do

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Název nakladatele

ČZU

Místo vydání

Praha

Místo konání akce

Praha

Datum konání akce

22. 9. 2004

Typ akce podle státní příslušnosti

EUR - Evropská akce

Kód UT WoS článku

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