Impacts of intake of trichothecenes (Fusarium sporotrichioides) for dairy calves: Effects on animal growth, oxidative and inflammatory response

The objective of the present study was to evaluate the impacts of trichothecenes (Fusarium sporotrichioides) for dairy calves on animal growth, oxidative and inflammatory responses in the presence or absence of essential oils. Twelve calves weaned at 70 days of age were divided into 2 groups: T-C (control) and T-EO (essential oils - oregano, thyme, basil and rosemary) in the period of 40 days consuming ration contaminated by trichothecenes (500 ppb). The animals in the T-EO group received a mixture of EOs via feed at a dosage of 0.75 mL per/kg of feed. Blood collections were performed on days 1, 20 and 40 for hematological and biochemical analyses; the fecal score was performed every 2 days on a scale of 1-5 and clinical examinations were performed 3 times during the experiment period. The animals were weighed at the beginning and at the end of the experiment; euthanasia of two calves per group for macroscopic and microscopic evaluation of several tissues (spleen, liver, duodenum, jejunum, ilium, cecum and colon) was performed at the end of the experiment. The calves in the T-EO group had a tendency (P = 0.07) of higher body weight when compared to the T-C. Treatment effect and treatment vs day interaction was detected for leukocytes and granulocytes variables, demonstrating a higher count of these cells in the T-EO group on both days (20 and 40), and the same behavior occurred for the distribution amplitude of erythrocytes (RDW). The enzymes alanine transferase (ALT), aspartate transferase (AST) and gamma glutamyl-transferase (GGT) showed higher serum activity in the T-C group (days 20 and 40). The levels of thiobarbituric acid reactive substances (TBARS) were lower in the serum of animals in the T-EO group. For calves in the T-EO group, glutathione S-transferase activity was higher in serum. Haptoglobulin and C-reactive protein levels were lower on days 20 and 40 in T-EO animals when compared to the T-C group. In the macroscopic and microscopic evaluations, which were collected at the end of the experiment after slaughtering the animals, liver and intestine did not show changes for the animals in the T-EO group, unlike the animals in the T-C group, which had moderately firm diffuse consistency of the liver and edema in the mesentery, as well as oxidative stress in tissues (liver, duodenum, jejunum, ileum, cecum and colon). The results concluded that the consumption of a mixture of EOs (essential oils - oregano, thyme, basil and rosemary) minimized the negative effects caused by trichothecenes in dairy calves, thus being an alternative to improving the immunological and antioxidant condition, as well as a possible adsorbent alternative.