Utjecaj porodne mase i dobi odojaka na eritrocitne pokazatelje

The preweaning period is the most critical phase in pig production. During that period the production parameters of small birth mass piglets are the poorest and losses are the heaviest. In this study red blood cell characteristics were investigated in suckling piglets of normal and small birth mass, regarding the various changes occurring after birth related to organ development, colostrum intake, degradation of fetal erythrocytes and parental globulins, acquirement of immunocompetence, environmental changes, stress, and other factors. The average values of erythrocyte numbers obtained in both groups of piglets after birth were below the lower threshold of the reference range for pigs and only reached it at 14 (piglets of normal birth mass) or at 21 days of age (small birth mass piglets). The average erythrocyte count at the end of the suckling period was significantly higher (P<0.01) than values established on the first day of life. The increase recorded is probably a result of accelerated erythropoesis in young animals after degradation of fetal erythrocytes. A significantly higher value (P<0.01) of hematocrits was recorded in both groups at the end of the suckling period in comparison with the first day. Only in the group of small birth mass piglets was there a statistically significant higher haemoglobin value (P<0.01) on the 21st day compared with the 1st day of life. All piglets had significantly lower values (P<0.01) of erythrocyte parameters (MCV, MCH and MCHC) at weaning than on the first day of life. Piglets of normal birth mass had significantly larger number of erythrocytes (P<0.05) and lower MCV value (P<0.05) at 7 days of age, and significantly lower MCV and MCH (P<0.01) in relation to low birth mass piglets at two weeks of age.Razdoblje sisanja u prasadi predstavlja presudnu fazu svinjogojske proizvodnje. U ovom istraživanju utvrđeni su hematološki pokazatelji odojaka od prasenja do odbića. Nakon prasenja dolazi do različitih promjena, koje su u vezi sa sazrijevanjem i razvojem organa, uzimanjem kolostruma, razgradnjom fetalnih eritrocita te majčinih globulina, stjecanjem imunokompetentnosti, okolišnim promjenama, utjecajem stresa i drugim čimbenicima. Dobivene vrijednosti prosječnog broja eritrocita odojaka nakon prasenja nalazile su se ispod, a tek u dobi od 14 dana unutar donje granice referentnog raspona za svinje. Prosječan broj eritrocita na kraju razdoblja sisanja bio je statistički značajno veći (P<0,01) od vrijednosti utvrđene prvog dana života. Ustanovljeni porast mogao bi biti posljedica ubrzane eritropoeze u novoprasene prasadi nakon razgradnje fetalnih eritrocita. Statistički značajno veća vrijednost (P<0,01) na kraju razdoblje sisanja, u odnosu na prvi dan utvrđena je i za vrijednost hematokrita. Zabilježene su i statistički značajno manje prosječne vrijednosti (P