Iatrogenic aspiration pneumonia (AP), often caused by incorrect drenching and feeding with inappropriate bottles, is a frequent condition that can lead to sudden death depending on the amount of aspirated fluid. The evaluation of clinical scores and blood gas analytes may provide valuable insights into the complications that may arise due to AP in later stages. In this study, the AP Group consisted of 23 Holstein breed calves aged 1-14 days, which developed clinical signs such as cough, nasal and/or ocular discharge, and respiratory distress after forced feeding with inappropriate bottles. The Control Group consisted of 11 healthy calves with similar characteristics. Clinical examinations, Calf Health Score (CHS) evaluations, and venous blood gas analysis were performed. Based on anamnesis, calves with AP were classified as either Acute or Chronic AP. In clinical examination, heart and respiratory rates were higher in the Acute AP Group compared to the other groups (P<0.001). Total CHS was higher in the AP Group than that in the Control Group (P<0.001). The pH, sO2, Cl and Hb levels of the AP Group were lower, and K and lactate levels were higher compared to the Control Group (P<0.031). Among all groups, the pCO2 levels were highest in the Acute AP Group (P<0.001). The Na level of the Chronic AP Group was lower than that of the Control Group (P<0.05). The hematocrit level was lowest in the Chronic AP Group (P<0.016). These findings suggest that venous blood samples can be effectively used to classify the course of AP in neonatal calves; significant alterations in venous blood gas, electrolyte levels, and CHS can be observed in affected animals; sO2 and pCO2 levels are particularly important in distinguishing between acute and chronic cases of AP; and clinical and laboratory findings may be similar to those observed in healthy animals in chronic cases depending on the body’s ability to compensate or tolerate the disease.