Naslov
Activities of AST, ALT and GGT in clinically healthy dairy cows during lactation and in the dry period

Autori
Stojević, Zvonko ; Piršljin, Jasna ; Milinković-Tur, Suzana ; Zdelar-Tuk, Maja ; Beer Ljubić, Blanka

Izvornik
Veterinarski arhiv (0372-5480) 75 (2005), 1; 67-73

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

Ključne riječi
AST ; ALT ; GGT ; dairy cows ; blood plasma ; lactation ; dry period

Sažetak
This study examined the activities of aspartate aminotransferase (AST ; EC 2.6.1.1), alanine aminotransferase (ALT ; EC 2.6.1.2) and gamma-glutamyltransferase (GGT ; EC 2.3.2.2) in the plasma of 120 dairy Holstein breed cows divided in four groups according to the production period. The cows were held in an intensive farm breeding. Their meal consisted of ordinary alfalfa, silage, hay and concentrates with energy and protein supplements. The first group consisted of animals from the 10th until 45th day of lactation, the second from the 46th until 90th day of lactation, and the third was from the 91st day of lactation until the end of milk production. Cows in the dry period were in the fourth group. The highest activity of AST was determined in the first production period, while enzyme activity in the second and third period was higher than in the dry period. ALT activity showed a statistically significant increase since the 46th day of lactation until the dry period, and the activity in the second and third period was statistically higher than in the dry period. GGT activity in the first production period and in the dry period was statistically higher in comparison with the second and third period. Research results showed a significant influence of milk production and the dry period on the activities of examined enzymes in the blood plasma, and we can come to a conclusion that there is a need of constant monitoring for the described parameters during production.

Izvorni jezik
Engleski

Znanstvena područja
Veterinarska medicina

POVEZANOST RADA