Dietary Supplementation of Chestnut Tannins in Prepartum Dairy Cows Improves Antioxidant Defense Mechanisms Interacting with Thyroid Status

Abstract

Cows in the peripartal period undergo changes in thyroid hormones and are susceptible to lipomobilization and/or oxidative stress. The addition of chestnut tannins as polyphenolic compounds in the diet may improve feed efficiency and prevent oxidative stress-related health disorders in transition cows. However, the relationship between chestnut tannin supplementation and thyroid function, which plays an important role in metabolic regulation, has not been investigated in dairy cows. This study was conducted to investigate the effects of chestnut tannin supplementation during the close-up period on thyroid status and to evaluate the interaction between thyroid hormones and oxidative stress biomarkers in prepartum dairy cows. Forty multiparous Holstein cows were fed either a diet containing chestnut tannins (CNTs, n = 20, 1.96 g chestnut tannins/kg feed, dry matter) or a non-supplemented diet (CON, n = 20) during the last 25 ± 2 days of gestation. Blood samples were collected on the first day of study (before chestnut tannin supplementation) and d 5 before parturition to measure hormonal and oxidative stress indices. Serum concentrations of T3 (p = 0.04) and T4 (p = 0.05) were higher in CNT cows than in the CON group on day 5 before parturition. Thyroid status of CNT cows was associated with higher serum total antioxidant capacity (T-AOC, p < 0.01), activities of superoxide dismutase (SOD, p = 0.03) and glutathione peroxidase (GPx, p = 0.01), and reduced glutathione concentration (GSH, p = 0.05). Serum thiobarbituric acid reactive substances (TBARS) were lower (p = 0.04) which was associated with lower aspartate aminotransferase (AST, p = 0.02), and lactate dehydrogenase (LDH, p = 0.01) activities in the CNT than in the CON group. Estradiol and progesterone did not differ between CNT and CON cows. Chestnut tannin supplementation improves antioxidant protection, prevents oxidation-reduction processes, reduces the degree of liver cell membrane damage, and protects thyroid tissue from damage, allowing higher T3 and T4 synthesis. Considering the importance of the thyroid hormone status before parturition, mechanisms of thyroid hormone regulation in CNT-supplemented dairy cows require more detailed investigations.

Chestnut tannin supplementation can improve immune response and kidney function in prepartum dairy cows

“…As expected, CNT cows had higher activities of the total antioxidants (ABTS), confirming the strong antioxidant properties of chestnut tannins (Santillo et al, 2022). These results are consistent with the findings of Liu et al (2013) and Prodanović et al (2023), who observed the stimulatory effect of chestnut tannins on endogenous and general antioxidant defence against free radicals in the liver and plasma of transition dairy cows. The consistency of the results of two different methods (DPPH and ABTS scavenging) in the assessment of antioxidant capacity confirmed their reliability in determining the antioxidant activity of chestnut tannins, and demonstrated the beneficial role of CNT in attenuating oxidative damage during the periparturient period.…”

“…According to Jonsson et al (2013), increases in serum oestradiol levels in response to stressors could cause haematological changes, including an increase in the number of neutrophils and a decrease in lymphocytes. However, as reported previously and demonstrated in the present experiment, tannin supplementation did not affect the concentration of this hormone compared to nonsupplemented cows (Bešlo et al, 2022;Prodanović et al, 2023). Therefore, sex steroid probably did not contribute to the differences observed in the immune status between the groups after tannin supplementation.…”

“…Second, thyroid hormones are thought to be involved in maintaining immune function in response to environmental stimuli and stress-mediated immunosuppression (Dorshkind and Horseman, 2000). Therefore, increased serum T3 and T4 concentrations demonstrated in cows supplemented with chestnut tannins in a previous study (Prodanović et al, 2023) could indicate that tannins modulated the immune system response in dry dairy cows. Third, the improved metabolism of CNT cows during the periparturient period (Prodanović et al, 2021) could be a contributing factor to the higher lymphocyte counts in CNT cows.…”

“…The fluctuations in the metabolic and/or antioxidant status near parturition were shown to influence the effect of dietary tannins on colostrum quality, indicating an additional positive effect of chestnut tannins on the immune system of the mammary gland (Prodanović et al, 2021). The positive effect of dietary tannins has also been attributed to the reciprocal regulation between thyroid response and oxidative stress (Prodanović et al, 2023).…”

Chestnut tannin extract modulates growth performance and fatty acid composition in finishing Tan lambs by regulating blood antioxidant capacity, rumen fermentation, and biohydrogenation

“…However, the biological processes underlying how tannins respond to antioxidant enzymes are not fully understood. Nevertheless, the addition of CTE to the diets of transition cows increases their plasma SOD and GSH-Px activities [ 54 ]. Correspondingly, in the present study, CTE considerably improved plasma SOD and GSH-Px contents of Tan lambs in a dose-dependent manner.…”