Productivity of milk and milk composition of an indigenous sheep breed in Macedonia

Abstract

Several production traits have been examined in 180 Ovchepolian sheep during a four-year production period (2010-2013). The sheep ranged in age from the first to the 7th lactation and 4319 individual lactation controls were realized in total. Besides the basic statistics, all data were analysed using a multi-factorial fixed model. The influence of certain factors was studied using the F-test and the analyses were made using the SPSS set of programs. Most of the factors (year, lactation, lambing month and number of milk recording) had a highly significant influence (P (lt) 0.001) on daily milk production (milk from the morning, evening and the total amount of milk, % of milk fat and kg fat) in this breed of sheep. The month of milk recording also had a significant influence (P (lt) 0.05) on all traits. Only fertility had no impact on the variations in the tested parameters, aside from the total daily milk, on which a highly significant influence was manifested (P (lt) 0.01). The average milk lactation among the tested sheep population during all four years was, on average, 58 ± 0.247 l, while the production of milked milk for the same period was 37 ± 0.217 l. The length of the lactation period in these sheep for the four years studied averaged 182 ± 0.31 days. The maximal daily milk yield in this sheep population was measured in 2011 (0.302 ± 0.26 l). Regarding their age, the highest daily milk yield was determined in sheep in the third lactation (0.365 ± 0.26), while those in the 7th lactation had the lowest (0.255 ± 0.27).

Ispitivano je nekoliko proizvodnih svojstava (laktacijska proizvodnja mleka, proizvodnja mleka u dojnom periodu, proizvodnja mleka u muznom periodu, dužina dojnog perioda, dužina laktacije, proizvodnja mleka u toku jutarnje muže, proizvodnja mleka u toku večernje muže i dnevna proizvodnja mleka) kod ukupno 180 ovcepoljskih ovaca, u toku četiri proizvodne godine (2010-2013). Uzrast ovaca bio je od prve do sedme laktacije, i kod njih je bilo realizovano ukupno 4319 individualnih laktacijskih kontrola. Osim bazične statistike, svi podaci su analizirani pomoću višefaktorijalnog fiksnog modela. Uticaj posebnih faktora ispitivan je pomoću F-testa, dok su analize urađene pomoću programskog paketa SPSS. Veći broj faktora (godina, laktacija, mesec jagnjenja i broj kontrole mleka), imali su visoko značajni uticaj (P (lt) 0,001), na dnevnu proizvodnju mleka (jutarnje, večernje i ukupno mleko, % mlečne masti i kg mlečne masti), kod ove rase ovaca. Mesec kontrole mleka u odnosu na sva svojstva imao je visoko značajni uticaj (P (lt) 0,001), osim na % mlečne masti (P>0,05). Jedino plodnost nije imala nikakav uticaj na varijacije ispitivanih parametara, osim na ukupnu dnevnu produkciju mleka, na koju je manifestovala visoko značajni uticaj (P (lt) 0,001). Prosečna laktacijska mlečnost kod ispitivane populacije ovaca, sa sve četiri godine u proseku je bila 58 ± 0,247 l, dok je proizvodnja muznog mleka u istom periodu bila 37 ± 0,217 l. Dužina laktacijskog perioda u toku četiri ispitivane godine u proseku je bila 182 ± 0,31 dana. Maksimalna dnevna mlečnost kod ove rase ovaca, izmerena je u toku 2011. godine (0,302 ± 0,26 l). U odnosu na starost, najveća dnevna mlečnost je utvrđena kod ovaca u trećoj laktaciji (0,365 ± 0,26), a najniža u sedmoj laktaciji (0,255 ± 0,27).