The aim of this study was to assess the productive health of the meat hybrid ROSS 308 parent flock during the laying season at regular twomonth intervals by means of selected haematological (haematocrit, haemoglobin) and biochemical (total protein, glucose, cholesterol, alanine aminotransferase, aspartate aminotransferase, calcium, phosphorus, magnesium, sodium, potassium) parameters. To assess the metabolic profile in a randomly selected set of laying hens (n = 30), blood was collected by vena basilica puncture and stabilized with heparin. The productive capacity of the parental flock was assessed on the basis of hatching egg laying capacity of laying hens (n = 5000). The experiment began after the adaptation period at 23 weeks and ended at 62 weeks of age of laying hens. Laying intensity during the study period ranged from 84.50% (30 weeks of age) to 50.10% (62 weeks of age), with weekly hatching egg production ranging from 5.60 (30 weeks of age) to 3.40 eggs (62 weeks of age). As hatching intensity decreased, the mean values of haematocrit, haemoglobin and aspartate aminotransferase gradually increased. On the other hand, the mean values of total protein, cholesterol, alanine aminotransferase, calcium, phosphorus, magnesium and potassium tended to follow hatching intensity. For plasma glucose and sodium levels, fluctuations in values were observed independent of hatching intensity. Information on the dynamic changes in the metabolic profile of meat hybrid laying hens, occurring during the hatching season, can serve as an important indicator for assessing the health status and welfare of hens.