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Tierarztl Prax Ausg G Grosstiere Nutztiere 2013; 41(02): 95-104
DOI: 10.1055/s-0038-1623156
Übersichtsartikel
Schattauer GmbH

Strategische hormonelle Fruchtbarkeitsprogramme bei Kühen

Teil 2: Präsynchronisation und ResynchronisationStrategic hormonal reproductive programs in cowsPart 2: Presynchronization and resynchronization
C. Schmidt
1   Tierärztliche Klinik Dr. Eller, Hofheim i. Ufr.
,
Z. Gajewski
2   Department of Large Animal Diseases with the Clinic, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw, Poland
,
A. Wehrend
3   Klinikum Veterinärmedizin, Klinik für Geburtshilfe, Gynäkologie und Andrologie der Groß- und Kleintiere mit Tierärztlicher Ambulanz, Justus-Liebig-Universität Gießen
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Publikationsverlauf

Eingegangen: 06. März 2012

Akzeptiert nach Revision: 02. November 2012

Publikationsdatum:
05. Januar 2018 (online)

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Zusammenfassung

Gegenstand und Ziel: Beschreibung der Methoden der hormonellen Präsynchronisation und Resynchronisation beim Rind. Material und Methode: Literaturübersicht. Ergebnisse: Da die Trächtigkeitsrate von Kühen, die ein Ovsynch-Programm durchlaufen, entscheidend davon abhängt, in welchem Zyklusstadium sich die Tiere zu Beginn des Programms befinden, wurden verschiedene Methoden der Präsynchronisation entwickelt, die auf dem Einsatz von PGF2α oder dem kombinierten Einsatz von PGF2α und GnRH-Analoga beruhen. Ein weiteres Problem stellt die schnellstmögliche Besamung nicht tragender Kühe nach dem Ovsynch-Programm dar. Als Lösung wird die Behandlung aller Tiere nach der Besamung 7 Tage vor der Trächtigkeitsuntersuchung empfohlen. Stellt sich eine Kuh am Tag der Trächtigkeitsuntersuchung als nicht tragend dar, wird ihr PGF2α verabreicht, um möglichst schnell eine erneute Insemination durchführen zu können. Klinische Relevanz: Durch den Einsatz von Programmen zur Präsynchronisation und Resynchronisation kann die Fruchtbarkeitsleistung einer Milchviehherde gesteigert werden.

Summary

Objective: Description of hormonal presynchronization and resynchronization methods in cattle. Material and methods: Review. Results: As the pregnancy rate of cows treated with the Ovsynch program primarily depends on the stage of the oestrous cycle at the time of program initiation, different methods of presynchronization based on the use of PGF2α and combinations of PGF2α and gonadotropin-releasing hormone analogues have been developed. An additional problem includes the earliest possible insemination of open cows following the Ovsynch program. As a solution to this problem a postinsemination treatment of all animals seven days before the scheduled date of the pregnancy ex amination is recommended.If a cow is found not to be pregnant by the pregnancy examination, it will be treated with PGF2α to enable a fur ther insemination as soon as possible thereafter. Clinical relevance: By utilizing presynchronization and resynchronization programs, the reproductive performance of a dairy herd can be increased.

Schlüsselwörter

Kuh - Fruchtbarkeit - Präsynchronisation - Resynchronisation

Key words

Cow - fertility - presynchronization - resynchronization
 

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