Aytaç AKÇAY, İsmail Safa GÜRCAN

Survival analysis on calving interval and gestation length in Simmental x South Anatolian Red F XB crossbred cows

Bu çalışmada, Simmental x Güneydoğu Anadolu F1XB1 melezi genç ve ergin çağdaki ineklerde, buzağılama aralığı ve gebelik süreleri, yaşam analizi metodu ile incelenmiştir. Çalışmanın verileri, Ceylanpınar tarım işletmesinde Ocak 1987 ile Ekim 1999 tarihleri arasında yer alan 1775 laktasyon kayıdından elde edilmiştir. Verilerin %3.1’i sensörlüdür. Genç ineklerin ortalama buzağılama aralığının, (382.26 ± 15.39 Gün) ergin yaştakilerden (386.27 ± 8.9 Gün) daha kısa olduğu (p

Simmental x Güneydoğu Anadolu kırmızısı F XB melezi ineklerin buzağılama aralığı ve gebelik süresinin yaşam analizi ile incelenmesi

The objective of this study was to compare the survival analysis for calving interval and gestation length in Simmental x South Anatolian Red crossbred F1XB1 cows. The data set consisted of 1775 lactation records from January 1987 to October 1991, of which 3.10% were censored. The mean calving interval was 382.26 days (15.39 S.D) for young cow group while it was 386.27 days (8.90 S.D) for old cow group. The mean calving interval in young cow group is shorter than old cow group (p

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