Study of adaptation in neonatal cloned Nelore calves: disorders of metabolic profile and bases for the use of mechanical ventilation in the treatment of respiratory disorders in bovine neonates

Abstract

Pursuing this line of research, related to internal medicine of cloned calves and in order to meet the recommendations of FAPESP that each researcher has only one project under his direction, this proposal was divided into two sub-projects addressing two crucial issues in understanding disorders of neonatal adaptation of cloned calves and the proposed treatments to minimize losses: Sub project 1: "Inter-relationships between neonatal adaptation disturbances to extrauterine life and the metabolic profile of cloned calves"The proposed experiment will be designed to better understand the energy metabolism of calf with a view to proposing protocols of care to newborns, which increases the survival of animals coming from high-risk pregnancies or animals born prematurely, to characterize the differences in the metabolic profile energy of Nelore calves and compare with Holstein calves; evaluate the influence of prematurity in energy metabolism of calves; verify particularities energy metabolism of cloned calves, to study the possible impact of disorders of energy metabolism in fetuses on energy metabolism and maternal acid base balance in late pregnancy, document the degree of glycemic control fetuses during the last 3 months of pregnancy through the determination of glycated hemoglobin and fructosamine. To evaluate the energy metabolism of pregnant cows in late gestation, 8 recipient clone embryo cows and 8 recipient Nellore embryo cows will be used. The animals will be examined in the final 30 days of gestation, blood samples being performed at the following times: 260 days of gestation, 270 days of gestation, 280 days of gestation, 285-290 days of gestation, immediately after induction of labor, 12,24 and 36 hours after induction of labor. The last sample will be collected at 48 hours after induction of labor or at the time of cesarean section. It should be noted that in pregnancies clones delivery is between 36 and 48 after the induction of labor. For conducting evaluations in calves, will be used 29 newborn Holstein and Nelore calves were divided into 4 experimental groups: 5 cloned Nelore calves, 8 preterm Nelore calves , 8 Nelore at term calves and 8 Holstein at term calves. Blood samples will be performed at the following times: 0,3,6,12,24,36,48,72,120 and 168 hours of life.- "Mechanical Ventilation in cloned calves: Bases for use in bovine neonatal respiratory disorders"To standardize the techniques of mechanical ventilation and obtain the values of the parameters studied, will be used 24 premature calves obtained by cesarean section performed between 265 and 270 days of gestation, without labor induction to ensure that there is a serious respiratory disorder, and the ventilatory support will be used in these animals maintained during the first two days. The collection of material for determination of respiratory and hemodynamic variables (heart rate, respiratory rate, systolic and diastolic arterial blood pressure, mean arterial pressure, cardiac index, pulmonary artery pressure, pulmonary capillary wedge pressure, central venous pressure, temperature, pH,pCO2,pO2,HCO3, BE,SO2), evaluation of oxidative stress and analysis of condensate exhaled breath for determination of pulmonary nitric oxide, as an indicator of lung injury, will be performed at the following times: 0 - 2, 2 - 4, 6, 12, 24, 36, 48, 72 hours and 7 days of life. In the first hours of life, the animals will be evaluated in order to characterize the existence of severe respiratory distress requiring ventilatory support. The animals will be divided into three experimental groups consisting of 8 animals each: 1) invasive ventilation for tracheal intubation; 2) non-invasive mechanical ventilation with face mask; 3) control group composed of healthy calves born at term, who will not receive ventilatory support. (AU)