EFFECT OF DAYS OPEN AFTER FIRST CALVING ON SOME LIFE-TIME TRAITS IN BUFFALO COWS

Pencho Penchev, Yordanka Ilieva, Milen Boichev, Tzonka Peeva

Abstract: The study assigned 2221 Bulgarian Murrah buffalo cows having calved for first time within the period 1976-2001 on nine national farms. To test the effect days open after first calving on productive life and lifetime performance, using the software products LSMLMW and MIXMDL, an LS-analysis was carried out involving as additional sources of variance the fixed effects of age at first calving, first lactation milk yield, farm, season of first calving, period, and genealogical line. The results indicate that days open after first calving plays significant effect on the variation of life-time productivity, expressed in higher total and relative milk yield per life time in the early calving buffaloes. Long days open after first calving leads to lengthening the life-time non-productive period. Days open does not affect duration of productive life significantly.

Keywords: buffaloes; first days open; life-time traits; LS-analysis

Date published: 2023-03-01