Vpliv sezone telitve na potek laktacijske krivulje krav molznic

Mihelčič, Jerca (author), Žgur, Silvester (mentor), Voljč, Mojca (comentor)

V nalogi smo preučevali vpliv sezone telitve na potek laktacijske krivulje krav molznic. Ne le sezona telitve, temveč tudi dolžina dneva, prehrana, zdravstveno stanje, starost ob prvi telitvi, frekvenca molže in pasma pomembno vplivajo na potek laktacijske krivulje. V nalogo smo vključili pregled podatkov, ki smo jih pridobili iz Centralne podatkovne zbirke GOVEDO za obdobje med letoma 2010 in 2022 za molznice rjave, lisaste in črno-bele pasme, vključene v kontrolo. Mlečno vztrajnost smo izrazili s perzistenčnima indeksoma P2:1 in P3:1 in ju prikazali po pasmah za prvesnice in krave po posameznih mesecih telitve. Laktacije, ki se začnejo jeseni in pozimi, imajo praviloma najboljšo mlečno vztrajnost. Molznice, ki so telile jeseni (septembra in oktobra), so imele najboljšo mlečno vztrajnost, najslabšo pa tiste, ki so telile spomladi. Krave in prvesnice črno-bele pasme so imele boljšo mlečno vztrajnost kot krave in prvesnice rjave ter lisaste pasme. Pri vseh treh pasmah so imele prvesnice boljšo mlečno vztrajnost v primerjavi s kravami.

• Language: Slovenian
• Keywords: govedo, krave, molznice, sezona telitve, laktacijska krivulja, Slovenija
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: BF - Biotechnical Faculty
• Year: 2024
• PID: 20.500.12556/RUL-162531
• Publication date in RUL: 25.09.2024

Secondary language

• Language: English
• Title: the effect of calving season on lactation curve characteristics in dairy cows

Abstract

In this thesis we were studying the effect on the course of the lactation curve in dairy cows. Not only calving season but also day length, nutrition, health status, age at first calving, milking frequency and breed have a significant influence on the lactation curve. We have also included in this thesis a review of data obtained from the Central Cattle Database for the period 2010-2022 for Brown Swiss, Simmental and Holstein dairy cows included in the milk recording. Milk persistency was expressed by persistency index P2:1 and P3:1 and reported for primiparous and multiparous cows of different breeds by months of calving. Lactations starting in autumn and winter have usually the best milk persistency. Cows calving in autumn (September, October) had the best milk persistency, while cows calving in spring had the worst. Holstein cows had better milk persistency than Brown Swiss and Simmental cows and heifers. In all three breeds, primiparous cows had better milk persistency compared to multiparous cows.

• Keywords: cattle, dairy cows, calving season, lactation curve, Slovenia