Acid-base balance modifications in the lamb and kid during the first week of life

In the lamb and the goat kid, the neonatal period represents a critical stage, as the newly born animals have to adapt to the extra-uterine life. The purpose of this study was to obtain physiological reference values as indicators of dynamic homeostatic processes occurring during the first week of life in the lamb and kid. Two groups of five “Valle del Belice” lambs and five “Girgentana” kids, respectively, were used in the trial. Starting from the first day of birth and for the following 6 days, all animals underwent blood sampling by means of a jugular venipuncture and blood pH, carbon dioxide partial pressure (pCO2), oxygen partial pressure (pO2), standard bicarbonate concentration (SBC), bicarbonate concentration (HCO3−) and total carbon dioxide (TCO2) were determined using a selective ion haemogasanalyzer. The values were statistically processed for repeated measurements and the Bonferroni test of multiple comparisons, to determine significance differences parameters. There were no statistically significant differences regarding the pH, pCO2, HCO3−, and TCO2 between the two groups, Group A (GA: lambs group) and Group B (GB: kids group). Significant differences were recorded for the pO2 values (GA: P < 0.001; GB: P < 0.0001) and SBC (GA: P < 0.01; GB: P < 0.01). pO2 values showed a constant and significant increase (P < 0.05) both for GA and GB groups, during the earliest part of the investigation. Furthermore pO2 values in the GB group showed a significant increase (P < 0.05), starting from the second day of the study. SBC showed a gradual increase during the observation period. Significant differences (P < 0.05) were recorded in the GA group between the second and third day, compared to the seventh day and in GB group for the first day, compared to the fourth and the fifth day. These results outline the occurrence of acid-base homeostatic mechanisms, and the physiologic evolution of the organs and parameters under investigation. Furthermore results underline differences between the species that needs to be further researched.