Small animal perinatology challenges: the influence of racial conformation on maternal adaptation to pregnancy and the influence of the obstetric condition on feto-neonatal transition period.

• Grant number: 17/11844-6
• Support Opportunities: Regular Research Grants
• Start date: November 01, 2017
• End date: December 31, 2019
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: Camila Infantosi Vannucchi
• Grantee: Camila Infantosi Vannucchi
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The aims of the present research are: to compare the fetal development, respiratory pattern and hemodynamic profile during gestation of brachiocephalic and non-brachiocephalic bitches, to analyze the influence of c-section on puppies respiratory features, alveolar content and gas exchange during the transition period; compare catecholamine (adrenaline and nor-adrenaline) concentrations and cortisol assay during the peripartum of bitches and neonatal transition period according to the obstetric condition (vaginal delivery or c-section); to analyze and compare the biochemical profile of the amniotic fluid of neonatal puppies born by vaginal delivery or c-section and correlate the respiratory performance of the initial neonatal period; quantify and compare the oxidative and antioxidant profile of neonatal puppies and peripartum bitches submitted by different obstetric conditions (vaginal delivery or c-section). This research will be divided into 3 experiments separately. In Experiment 1, pregnant bitches of brachiocephalic characteristics (n=10) and non-brachiocephalics (n=10) will be analyzed with the hypothesis that the physiological features of the respiratory pattern in association with the racial conformation of brachiocephalic bitches can promote hemodynamic alterations which may compromise maternal and fetal well-being. Bitches will be followed through the gestational period (initial - 33 to 26 days, mid - 43 to 46 days and late - 56 to 59 days of pregnancy) and during anestrous for the assessment of systolic, diastolic and mean arterial pressure, frequency and cardiac rhythm, peripheral oxygen saturation, arterial hemogasometry and ultrasonographic evaluation for the uterine scanning of fetal biometry, placental vascularization and maternal and fetal hemodynamics. For the experiment 2, we hypothesize that c-section can compromise the pulmonary clearance, predisposing puppies to respiratory alterations of the transition period. Amniotic fluid samples of 40 canine fetus will be collected during vaginal delivery or c-section in order to analyze the biochemical profiles. Neonatal Apgar score will be performed at 0, 5 and 60 minutes. Cardiac and respiratory frequencies and respiratory effort by pulmonary auscultation and body temperature will be measured at 0, 5, every 10 minutes until 60 minutes, 4, 12 and 24 hours after birth. Venous hemogasometry and catecholamine and cortisol assay will be performed at 0, 30, 60 minutes and 12 and 24 hours after birth. Pulmonary x-rays will be analyzed at birth, 12h and 24h and blood glucose and lactate will be measured at birth, 2h and 24h. In experiment 3, the hypothesis is that the obstetric condition (vaginal eutocia or c-section) causes differences on the bitches and neonatal antioxidant profile and oxidative stress. According to the obstetric condition, two experimental groups of bitches and 2 sub-groups of puppies will be formed: Vaginal eutocia group (n=10) and Initial and Final eutocia subgroups, respectively; C-section group (n=10) and Initial and Final c-section subgroups, respectively. Puppies were submitted to clinical analysis, measure of body weight, analysis of peripheral oxygen saturation and lactatemia. Analysis of serum oxidative stress and antioxidant profile will be performed at birth and through the peripartum period of bitches. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

DE ALMEIDA, LETICIA LIMA; DE ABREU, RENATA AZEVEDO; BRITO, MAIRA MORALES; GARDES, THAYNA PANTOJA; FLORES, RENATO BUENO; DA ROSA FILHO, ROBERTO RODRIGUES; VANNUCCHI, CAMILA INFANTOSI. Both spontaneous vaginal delivery and elective caesarean section influence neonatal redox status in dogs. VETERINARY RECORD, NOV 2021. (17/11844-6, 16/24731-2)