Colostrum supplementation with n-3 fatty acids does not alter calf outcome on a healthy commercial farm

Abstract

Our objective was to supplement colostrum with n-3 fatty acids (FA) to provide anti-inflammatory mediators that may improve the immune response of neonatal calves. Elevated markers of inflammation have been associated with increased occurrence of calf disease in early life, thus decreasing animal productivity. We hypothesized that a colostrum supplement containing 60-mL of a 1:1 ratio fish:flaxseed oil blend with or without 200 mg of α-tocopherol might provide an advantageous start to early life by decreasing oxidative stress and regulating the inflammatory response. Calves were blocked by birth order and randomly assigned to 1 of 3 treatments: no supplement added to colostrum (control), 60 mL of 1:1 fish:flaxseed oil blend, and 60 mL of 1:1 fish:flaxseed oil blend with 200 mg of α-tocopherol. In total, 180 heifer calves (n = 60 per treatment) were enrolled on a commercial farm. After colostrum feeding, all calves were housed in individual hutches and fed milk replacer 3 times per day. Health was scored 3 times per week until weaning at 8 wk of age. Weight, wither height, and heart girth were measured after birth, 3 wk, and 8 wk of age to assess preweaning growth. A subgroup of 54 calves (18 blocks or 18 calves per treatment) were sampled 2 d (± 8 h) after birth to evaluate oxidant status, serum total protein, and inflammatory gene and cytokine protein expression in blood after an in vitro lipopolysaccharide (LPS) challenge as indicators of health and immunity. At 9 wk, calves were transported 18 h to another farm, and medical records were kept as an indicator of disease incidence up to 13 wk of age. Calf mortality was 1.8%, which is below industry average, and exceptional health scores were observed throughout the study. Health scores and growth were similar throughout the preweaning period regardless of treatment. Serum total protein indicated successful passive transfer in all calves, and oxidant status index was not affected by treatments on d 2 of age. Concentrations of tumor necrosis factor α increased with LPS stimulation, but the increase was not altered by treatment. Likewise, leukocyte gene expression of tumor necrosis factor α, IL-8 and IL-10, and cyclooxygenase-2 increased upon LPS stimulation, but the fold change did not differ with treatment. In conclusion, 60 mL of 1:1 ratio fish:flaxseed oil colostrum supplement did not enhance preweaning calf performance. Supplementing n-3 FA in a one-time meal may not provide the anti-inflammatory benefits observed with continuous feeding.