Naslov
Prediction of lactation milk yield using various milk recording methods

Autori
Gantner, Vesna ; Jovanovac, Sonja ; Raguž, Nikola ; Klopčić, Marija ; Solić, Drago

Izvornik
Biotechnology in animal husbandry (1450-9156) 24 (2008), 3-4; 9-18

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
dairy cows ; prediction ; lactation milk yield ; milk recording methods

Sažetak
The objective of this study was to determine the effect of various milk recording methods (A4, AT4, A6, AT6) on prediction accuracy of 100, 200 and 305-day milk yield. The data used in this study were 11, 430 individual test-day milk yield records collected from November 2004 to November 2006 on 813 cows reared on 15 family farms in Croatia. Milk recording was performed according to A4 and A6 milk recording method by the field officer of the Croatian Livestock Centre. From the corrected database with test-day records, two different datasets were created. The first dataset (A4 ; n = 7, 500) included test day records collected every four weeks, while the second dataset (A6 ; n = 3, 830) included test day records collected every six weeks. When lactation milk yields were predicted from alternative milk recording methods (AT4, AT6), daily (24 h) milk yield was estimated from single evening or morning milk yield using linear model that taken into account effect of interval between successive milkings. Lactation milk yield was calculated for three different days in milk (100, 200 and 305 days) using the Test Interval Method (TIM) that is reference method by ICAR (ICAR, 2003). Results show that the alternate milk recording method at 4-week intervals provides low bias and high accuracy of prediction of 100, 200 and 305-milk yields, while milk recording methods at 6-week intervals gives prediction of 305- milk yield with higher bias and lower accuracy.

Izvorni jezik
Engleski

Znanstvena područja
Poljoprivreda (agronomija)

POVEZANOST RADA