Abstract
<jats:p>Early-life nutrition is a critical determinant of health and survival in dairy calves. However, practical quantitative thresholds linking colostrum quality and early feeding practices with neonatal health outcomes under commercial farm conditions remain insufficiently defined. Within the framework of early-life nutritional management, this study evaluated the combined effects of colostrum quality and early colostrum feeding practices on digestive health and survival of dairy calves under commercial farm conditions. Field data were collected from 250 Holstein calves reared on commercial breeding farms in western Kazakhstan. Colostrum quality was assessed using Brix refractometry and classified into quality categories, while early feeding practices were categorized according to the timing and adequacy of colostrum administration. Calves receiving timely and adequate volumes of high-quality colostrum exhibited a significantly lower incidence of digestive disorders (5.9-23.0%) and higher survival rates (88.2-100%) compared with calves exposed to delayed or inadequate early-life management. The combined classification of colostrum quality and feeding management enabled the identification of distinct neonatal risk groups associated with substantially different health outcomes. These findings support the use of a simple, field-applicable risk stratification approach as a preventive management tool for improving neonatal calf health and survival in commercial dairy systems.</jats:p>