Theses and Dissertations Collection

During the periparturient period, dairy cows reduce their energy consumption, and this induces mobilization of stored nutrients to support fetal development and milk production. Some infectious diseases and metabolic disorders may occur during the periparturient period. The objective of this study was to determine the relationship between serum metabolites of dairy cows and calves with the health status of the periparturient cows. Blood samples from periparturient cows were obtained (Farm A, n = 645; Farm B, n = 559, respectively) on d-21, d-7, d+1, d+7 and d+14 relative to calving. Blood samples of calves were obtained within the first 4 days of life (Farm A, n =429; Farm B, n = 428, respectively). Sera were analyzed for α-tocopherol, β-carotene, retinol, haptoglobin (HP), β-hydroxybutyrate (BHB), and glucose (calves only). Additionally, 115 healthy and mastitic or lame cows were randomly selected for milk fatty acid composition and serum type1/type 2 immunity balance analysis. The type 1/type 2 immune balance was evaluated by measuring the relative quantity ratio of immunoglobulin G1 and G2 subclasses (IgG1/IgG2) using a rapid D2Dx immunity test. Health records were categorized based on the occurrence of postpartum diseases. Data were analyzed using linear mixed models in SAS with significance declared at P ≤ 0.05. Results showed that cows with mastitis had significantly greater serum retinol concentration compared with that of healthy cows during postpartum, as well as serum α-tocopherol was affected by time, seasons, and mastitis interaction (farm A). Furthermore, cows with pneumonia and lameness had lower serum α-tocopherol and retinol compared with that of healthy cows at postpartum. Cows with mastitis had lower serum α-tocopherol and β-carotene (farm B). Retained placenta (RP) cows had lower serum retinol, and RP cows tended to decrease serum retinol in their calves (Farm B). Serum HP was lower when cows had pneumonia at d+1, and higher at d+14 (Farm A). Greater HP was observed with RP cows at d+1 and pneumonia (Farm B). Serum BHB was greater at d+7 and +14 for cows with lameness and RP, as well as greater in pneumonia cows (Farm B). The D2Dx immunity test score was greater at d+14 for diseased cows corresponding to a decreased relative quantity ratio of IgG1/IgG2. Serum glucose in calves was greater when the calves were born from the RP dams. No significant difference in milk fatty acid composition between diseased and healthy cows was observed. In summary, diseases affected the lipid-soluble vitamins status and serum metabolites of periparturient cows, and consequently, calves may experience health issues. Future study should focus on the disease effect in the milk lipid-soluble vitamins and obtain blood samples from Oregon commercial dairy farms to gain diseases in nutrients metabolites in the Pacific Northwestern region.