Acid-base status in newborn calves during the first days of life considering different states of vitality]

The aim of this study is to describe the differentiations of the acid-base status in bovine neonates during the first 96 hours of life. Due to the short intervals in the taking of blood samples, noticeable fluctuations in the acid-base status during the first minutes and hours of life of newborn calves were documented. Altogether, 25 matures and eutrophe calves of the DSB, DRB and DFV breeds were provided by the clinic for this study. Apart from an immediate post natum clinical interpretation of the vital signs in the neonates-using the APGAR-score-the pH value, current Base Excess and the CO2 pressure were simultaneously ascertained. Further continuous evaluation of the acid-base status was subsequently followed in the first phase of adaptation. For that alone, twelve blood samples were taken from the vena jugularis within the first 60 minutes after parturition. Until the end of the examination period on the fourth day of life, the tests amounted to 26 measurements altogether per experimentee. Due to the concrete results ascertained from the initial clinical and laboratory observations, the experimentees could be divided into distinct classes of vitality. The acid-base status of all the calves deteriorated during the first minutes of life, indicating that the pH value and Base Excess fall clearly under the initial level in all aspects of vitality directly post natum. On average the minimum pH values are reached between the third and 15th minute of life and remain between 0.019 and 0.096 below the initial values during this period. A varying rapid increase of the pH value follows, together with a balancing out of the Base difference. Despite isolated individual variations as the acid-base status develops, the lowering of the pH values in the first minutes of life is assessed as being a normal biological phenomenon. Deviations from this occur rarely (8%) and do not conform to the norm. The pH value stabilization in connection with this crucial early postnatal phase occurs to such a high degree that, without stagnation, on average all experimentees show pH values between 7,270 and 7,300 after 180 minutes of life-regardless of which vitality group they belong to. After reaching this common value at the end of the third hour of life, the further development of the ph values and the consequential resulting parameters in all three vitality groups are similar. A stagnation of the rising pH value between the 4th and 12th hour of life was established during the examination. Moderate stabilization then set in after this phase. Between the 24th and 36th hour of life all experimentees reached an average highest pH value of 7,400. Until the end of the examination period, however, this then dropped slightly to values between 7,380 and 7,395.