Praćenje rane gravidnosti i rane embrionalne smrtnosti primjenom ultrazvučne pretrage i određivanjem razine trofoblastičnoga proteina i progesterona u kravljem serumu

Abstract

The aim of study was to investigate the role of pregnancy-associated glycoproteins (PAG) in early pregnancy, as well as the possibility of using PAG and ultrasound as diagnostic tools in the diagnosis of embryonic mortality. Our research included 73 Simmental cows, 3-7 years old, which calved every year. According to ultrasound findings (on the 17th, 24th, 35th and 45th day following AI), the cows were divided into 3 groups: pregnant cows (n = 34), non-pregnant cows (n = 18) and cows which had suffered embryonic mortality (n = 21). Blood samples were collected every 72 hours between the 12th and 45th day following AI and levels of progesterone and pregnancy-associated glycoproteins (PAG) were determined. Statistical analysis of variance for progesterone at days 12, 21 and 35 following AI showed significant differences between pregnant cows and both the non-pregnant and embryonic mortality groups (P>0.05). PAG variance analysis at days 24, 30 and 34 following AI showed highly significant differences (P>0.01) between the non-pregnant and both the embryonic mortality and pregnant groups. On the other hand, variance analysis showed that mean values for PAG at days 40 and 45 following AI were highly significantly different (P>0.01) between the pregnant and both the nonpregnant and embryonic mortality groups. The conclusion emerged that it is impossible to determine embryonic mortality merely on the basis of progesterone profile, but it is easy to distinguish pregnant from non-pregnant cows, supposing cows to be more than 21 days pregnant. It is very easy and accurate to distinguish non-pregnant cows from cows that have suffered early embryonic mortality. Furthermore, 98% of the cows in our research which had experienced embryonic mortality, lost their embryos 17-24 days after AI, visible in a drastic decrease in PAG seven and half to nine days later. Using PAG for pregnancy diagnosis enables us to prove the existence of live, vital embryos in utero 24 days after conception.Svrha ovog rada bila je istražiti ulogu trofoblastičnoga proteina (PAG) u fiziologiji rane gravidnosti u goveda kao i mogućnost njegove primjene te ultrazvuka u dijagnostici rane embrionalne smrtnosti. Promatrane su bile 73 krave simentalske pasmine, u dobi od tri do sedam godina, u kojih nisu ustanovljene poteškoće s plodnošću. Sve su držane na pet obiteljskih gospodarstava u Međimurskoj županiji, u uzgojima koji su brojili od osam do 20 krava. Krave su bile podijeljene u tri skupine: gravidne krave (n = 34), krave sumnjive na ranu embrionalnu smrtnost (n = 21) i negravidne krave (n = 18). Na osnovi ultrazvučnih pretraga i laboratorijskoga praćenja razine progesterona i trofoblastičnoga proteina u serumu od 12. do 45. dana nakon UO donijeti su sljedeći zaključci. Na osnovi razine progesterona u serumu moguće je razlučiti gravidne od negravidnih krava, ali nije moguće dijagnosticirati embrionalnu smrtnost. Na temelju razine trofoblastičnoga proteina moguće je sa sigurnošću razlikovati krave kod kojih je nastupila embrionalna smrtnost nakon 16. dana gravidnosti od krava koje nisu postale steone. Embrionalna smrtnost vidljiva je na osnovi znatnoga pada razine trofoblastičnoga proteina u serumu majke, i to 7,5-9 dana nakon uginuća embrija, koliko iznosi i biološki poluživot trofoblastičnoga proteina u prvom mjesecu gravidnosti. Praćenjem razine trofoblastičnoga proteina u serumu moguće je pouzdano dokazati postojanje živoga vitalnoga embrija u maternici steone krave već nakon 24. dana steonosti. U istraživanju je 98% krava u skupini u kojoj je nastupila embrionalna smrtnost izgubilo embrij kad su bile gravidne 17-24 dana što predstavlja kritično razdoblje za preživljavanje embrija