Uporedni prikaz metaboličkih, endokrinih i reproduktivnih parametara visokomlečnih i autohtonih rasa krava

Abstract

Cilј ove doktorske disertacije bio je da se kod dve rase različitog genetskog potencijala u odnosu na proizvodnju mleka ispitaju adaptivne promene u metabolizmu koje su dovele do visoke proizvodnje mleka, uz mogući negativan uticaj na reproduktivnu aktivnost. Odabrano je 8 visokomlečnih holštajn krava (drţanih na farmama komercijalno-industrijskog tipa) i 8 niskomlečnih buša krava (drţanih u ekstenzivnom uzgoju na paši). Sve krave su bile u poslednjoj fazi graviditeta. Uzorci krvi od svih krava uzimani su 14 dana pre, kao i 14., 30. i 50. dana nakon telјenja i u njima je odreĎena koncentracija glukoze, BHBA, NEFA, ukupnih proteina, albumina, uree, ukupnog bilirubina, kalcijuma, fosfora, magnezijuma, holesterola, triglicerida, aktivnosti AST i GGT, koncentracije hormona (insulina, T3, T4, estradiola i IGF I) i relativna zastuplјenost IGF vezujućih proteina (IGFBP-2 i IGFBP-3). Testovi intravenskog opterećenja glukozom (IVGTT) su vršeni antepartalno (14 dana pre telјenja) i postpartalno (14 dana posle telјenja), odreĎeni su parametri kinetike glukoze i insulina i izračunati pokazatelјi insulinske rezistencije: RQUICKI, QUICKI i HOMA. Uzorci tkiva jetre, mišićnog i masnog tkiva, u kojima je odreĎena zastupljenost insulinskih receptora, uzeti su biopsijom 14. dana pre i 14. dana nakon telјenja. U uzorcima mišićnog i masnog tkiva odreĎivana i zastuplјenost GLUT-4. Procena reproduktivne aktivnosti vršena je observacijom spolјašnjih genitalnih organa, transrektalnom palpacijom i ultrasonografskim pregledom materice i jajnika 30. dana nakon telјenja. Koncentracija BHBA je u krvi krava holštajn rase, u odnosu na buše, bila značajno viša 30., a značajno niţa 50. dana posle telјenja, dok je bilirubinemija bila značajno niţa 30. i 50. dana posle teljenja, a značajno viša 14. dana posle telјenja. Proteinemija kod krava rase holštajn u odnosu na buše je bila značajno viša 14. dana pre, 14. i 30. dana posle teljenja, a značajno niţa 50. dana posle telјenja, dok je albuminemija bila značajno niţa 14. dana pre, 14. i 30 dana posle teljenja. Uremija kod holštajn u odnosu na buša rasu krava bila je značajno viša 30. i 50. dana postpartalno...

The aim of this PhD thesis was to compare two breeds of cows with different genetic potential in relation to the milk production and to investigate adaptive changes in metabolism that lead to high milk production, with a possible negative impact on reproductive activity. 8 high yielding Holstein cows (kept on commercial and industrial type farms) and 8 low milk production Buša cows (kept in extensive farming, grazing) was selected. All cows were in the final stages of pregnancy. Blood samples from all cows were taken 14 days prior to, and 14, 30 and 50 days after parturition, and in all samples were determined glucose, BHBA, NEFA, total protein, albumin, urea, total bilirubin, calcium, phosphorus, magnesium, cholesterol and triglycerides concentration, AST and GGT activity, the concentration of hormones (insulin, T3, T4, estradiol and IGF I) and the relative presence of IGF binding proteins (IGFBP-2 and IGFBP-3). Intravenous glucose tolerance tests (IVGTT) were carried out ante partum (14 days before calving) and post partum (14 days after calving), glucose and insulin kinetics parameters were determined and indicators of insulin resistance were calculated : RQUICKI, QUICKI and HOMA. Tissue samples of liver, muscle and adipose tissue, in which the presence of insulin receptors was determined, biopsies were taken 14 days before and 14 days after calving.In muscle and fat tissue samples the presence of GLUT-4 were determined. Evaluation of reproductive activity was carried out by observation of external genital organs, transrectal palpation and ultrasound examination of the uterus and ovaries 30 days after calving. BHBA concentration in the blood of Holstein cows, in relation to the Buša cows, was significantly higher 30, and significantly lower 50 days after calving, while the bilirubinaemia were substantially lower 30 and 50 days after calving, and significantly higher on day 14 after calving. Proteinaemia of the Holstein breed in relation to the Buša cows was significantly higher 14 days before, 14 and 30 days after calving, a significantly lower 50 days after calving, while albuminemia was significantly lower at 14 days before, 14 and 30 days after calving. Uremia in Holstein when compared to the Buša cows was significantly higher 30 and 50 days post partum...