Comparative analysis of some serum proteins and immunoglobulin G concentration in the blood of Yugoslav Trotter mares and newborn foals

Abstract

The comparison of some serum protein concentrations was performed on 12 Yugoslav Trotter mares and their newborn foals. The mares included in the evaluation were divided into two groups of 6 each. The mares in the first group were vaccinated against equine herpes virus 1 and 4, in the 5th, 7th and 9th month of pregnancy, while mares in the second group were not vaccinated at all. Pregnant mares were clinically observed during the last stage of pregnancy and blood for biochemical evaluations was sampled immediately after foaling. Foals were clinically observed for seven days after birth and blood samples were collected immediately after foaling (before nursing), and 24, 48, 72 and 168 hours after birth. Foals included in the evaluation were divided into two groups according to the group allocation of the respective mares. All mares gave birth to normal foals in expected terms. Biochemical examination revealed slightly lower total gammaglobulin and IgG values in tested mares compared to the values obtained in other horse breeds. The antibody titres against equine herpes virus-1 reached the level that provides sufficient protection in vaccinated mares. Gammaglobulin and traces of IgG were present in the blood serum of foals tested immediately after birth and before nursing. A significant increase of IgG and gammaglobulin concentration was revealed in all foals after the first 24 hours of life. The observed first day increase of concentration was followed by stagnation of gammaglobulin and IgG levels in all foals. Total protein values showed a significant increase 24 hours after the first intake of colostrum in all foals. Immunoglobulin G concentration established by semiquantitative test was considered low positive in 16.67% and in 33.34% of foals from vaccinated and unvaccinated mares, respectively. Turbidimetric analyses of the same samples revealed sufficient Ig transfer, i.e. Ig concentration over 8 g/L. Comparison of the results obtained by the two methods indicates that semi-quantitative field test results were clinically valid. There were no antibodies against EHV 1 in foals immediately after birth and before the first colostrum intake, and a highly significant increase of serum antibody level was recordered 24 hours after the onset of nursing in foals born from vaccinated mothers.

Ispitivanja su sprovedena na 12 kobila rase jugoslovenski kasač i njihovih 12 ždrebadi. Prva grupa od šest kobila je trokratno vakcinisana protiv EHV-1/4 tokom graviditeta, dok je druga grupa bila nevakcinisana. Od svih kobila su neposredno posle ždrebljenja uzeti uzorci krvi za biohemijski pregled. Novorođ ena ždrebad su klinički opservirana tokom prvih 7 dana života, uz uzimanje uzoraka krvi pre uzimanja kolostruma, zatim nakon 24, 48, 72 i 168 časova. Kod svih kobila su utvrđene nešto niže vrednosti gama globulina i IgG od vrednosti koje su zabeležene kod drugih rasa, pri čemu su vrednosti titra antitela na EHV-1 kod vakcinisanih kobila bile na nivou koji pruža zadovoljavajuću zaštitu, za razliku od nevakcinisanih kobila koje su bile ili seronegativne ili imale minimalan titar anti EHV-1 antitela. Kod većine ždrebadi je neposredno posle rođenja a pre prvog napoja u krvnom serumu ustanovljeno prisustvo gama globulina i IgG u tragovima, pri čemu je statistički značajno povećanje i gama globulina i IgG ustanovljeno posle prvih 24 časa. Primenom semikvantitativnog testa za određivanje IgG kod 25% ždrebadi utvrđene su niže vrednosti IgG (slabo pozitivne - što ukazuje na vrednosti od 5-8 g/L), iako je koncentracija IgG utvrđena imunoturbidimetrijom i kod njih bila veća od 8 g/L. Pre prvog unosa kolostruma u serumu ždrebadi nema antitela protiv EHV-1.