Abstract
During the onset of lactation, dairy cows experience increases in metabolic demands causing an increase in metabolic and oxidative stress that may result in disorders and reduced milk production. Dairy cows also represent a source of negative environmental impacts. Accordingly, natural products which alleviate these stresses and sources of environmental pollutants would be beneficial. The objective of this experiment was to determine how commercial products Lactobacillus fermented seaweed (Ecklonia radiata) (SWO; Animal Health Tonic; AgriSea Ltd.; Paeroa, NZ) and Lactobacillus fermented seaweed plus terrestrial plants (SWP; Fortress+; Agrisea Ltd.; Paeroa, NZ) influence dairy cow oxidative stress, environmental impacts, and production. Pregnant multiparous Holstein-Friesian × Jersey cross dairy cows (n = 27; body weight = 488.8 ± 47.6, mean ± SD) received daily oral doses of water (CON), SWO, or SWP. During the prepartum period (i.e., last third of gestation) the cows received 5-mL of their respective treatments once daily and this dose was increased to 100-mL per cow per d following calving. Ruminal fluid and blood samples were collected on d 0, 38, and 80 and blood samples were again collected 3 days after calving. Total volatile fatty acids concentrations in ruminal fluid were 26% greater (P = 0.05) in animals administered SWP compared with CON during the prepartum period. The CON cows had greater (P < 0.05) whole blood glutathione peroxidase activity than cows on SWP and SWO at all-time points following treatment application. After 80-d of administering the treatments and 3-d post calving, SWO and SWP had greater (P < 0.05) total antioxidant status of plasma (marker of ability to reduce oxidants). Three days after calving, the SWO and SWP cows had less (P < 0.05) plasma non esterified fatty acid concentrations and urea nitrogen than CON cows. Further, the SWP treatment had the lowest concentration of milk urea N and was less (P < 0.05) than CON. Accordingly, the calculated daily urinary N excretion of SWP was 18.0% lower (P < 0.05) than CON and SWO had a tendency (P = 0.07) to have 14.7% lower urinary N excretion than CON. Collectively, these results highlight the ability for these Lactobacillus fermented plant products to reduce oxidative stress during the onset of lactation in dairy cows and to reduce environmental impacts. This experiment provides important information for the improvement in periparturient dairy cows’ health and environmental impacts, which have economically important implications.
•Lactobacillus fermented plant products may reduce urinary nitrogen excretion.•These products had no effect on methane emissions.•These products reduced oxidative stress of transition dairy cows.•These products reduced metabolic stress of transition dairy cows.