Blood gas values and pulmonary hypertension as affected by dietary sodium source in broiler chickens reared at cool temperature in a high-altitude area.

One hundred and twenty day-old male chicks (Ross 308) reared at a cool temperature at high altitude were subjected to the following two treatments in a completely randomised design: (1) a group for which the sodium requirements were supplied by sodium chloride from day-old age and regarded as control, (2) a group similar to the control but for which 50% of the sodium requirements was supplied by sodium bicarbonate from day-old age. Provision of sodium equally from NaCl and NaHCO₃ significantly (P < 0.05) increased the partial pressure of oxygen and the saturation of haemoglobin with oxygen, and significantly (P < 0.05) decreased the heterophil to lymphocyte ratio. The right ventricle to total ventricles ratio shifted to lower values as a result of substituting NaHCO₃ for NaCl as a sodium source. Growth performance and carcass characteristics were not affected significantly by the dietary sodium source.