Fitoativos na alimentação de vacas leiteiras: impactos no metabolismo, imunidade e status oxidativo

• Ano de defesa: 2024
• Autor(a) principal: Leal, Karoline Wagner
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Santa Maria; Brasil; Medicina Veterinária; UFSM; Programa de Pós-Graduação em Medicina Veterinária; Centro de Ciências Rurais
• Palavras-chave em Português: Bovinos; Nutracêuticos; Antioxidantes; Anti-inflamatório; Imunidade; Cattle.; Nutraceutical; Antioxidants; Anti-inflammatory; Immunity; CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA
• Link de acesso: http://repositorio.ufsm.br/handle/1/33286

A data collection over the past six years was conducted to examine the effects of essential oils used as phytogenic additives in the diet of dairy animals, considering parameters such as feed intake, total apparent digestibility, methane emissions, and milk production, based on studies published between 2018 and 2023. The electronic literature search resulted in a careful selection of articles, which were reviewed and tabulated for evaluation. The results show that 51.35% of the articles reported no significant effects of phytogenic additives on milk production. However, 66.67% of the studies observed increased feed efficiency, and 50% reported effects on apparent digestibility. Additionally, there was a reduction in methane emissions in animals treated with phytogenic additives. Sharing these results with dairy professionals may promote more sustainable and effective practices, as well as support future research and innovations in animal nutrition, aimed at both productive efficiency and environmental sustainability. An experimental study was conducted to verify whether the addition of phytogenic compounds based on essential oils (carvacrol, eugenol, cinnamaldehyde) and oleoresin of pepper (capsaicin) to the diet of Jersey cows at the beginning of lactation affects anti-inflammatory, antioxidant, and immunomodulatory responses, as well as the effects of the additive on blood metabolites, ruminal fermentation, digestibility, and milk production and composition. In the pilot experiment, six primiparous Jersey cows (370.00 ± 17 kg body weight; 13.02 kg dry matter intake (DMI); 21 days of lactation and average milk production of 20 ± 2 liters per day) were allocated in a 2 x 2 crossover experimental design with two 28-day experimental periods and two treatments. Blood, milk, and ruminal fluid were collected, and at the end of each period, feed and fecal samples were collected to assess the apparent digestibility of nutrients. The groups were control (CLT) without supplementation and treated (BEO) with the addition of 150 mg/kg of dry matter of the phytogenic additive to the concentrated portion of the diet. The BEO group cows had a lower number of leukocytes (P ≤ 0.05) and lymphocytes (P ≤ 0.02), but total protein and globulin levels were higher on days 21 and 28 (P ≤ 0.01). In the BEO group, levels of immunoglobulin A, heavy chain immunoglobulin, and transferrin were higher (P ≤ 0.05). Ceruloplasmin, haptoglobin, and C-reactive protein levels were lower in the BEO group (P ≤ 0.05). Lipid peroxidation and protein carbonyl content were lower in the BEO group. Total antioxidant capacity (P ≤ 0.09) and the activity of glutathione S-transferase (P ≤ 0.03) and glutathione peroxidase (P ≤ 0.05) were higher in the BEO group. The cows in the BEO group showed lower pH (P ≤ 0.05), acetic acid concentrations (P ≤ 0.01), and higher protozoa counts (P ≤ 0.01). Our results suggest that phytogenic supplementation has positive effects on the health of Jersey cows in early lactation, characterized by immunostimulatory, antioxidant, and anti-inflammatory effects. Based on the pilot study results, a second experiment was conducted to evaluate traditional and alternative inflammatory pathways that may be related to the consumption of phytogenic additives (carvacrol, eugenol, cinnamaldehyde, and pepper oleoresin) in the diet of Jersey cows. Twenty pregnant Jersey cows were divided into two groups: control, without additive consumption, and treatment, with the addition of phytogenic additives (PHYTO) to the concentrated portion of the diet (150 mg/kg of dry matter). Blood samples were collected on experimental days 1, 7, 14, 21, 28, 35, and 42 via coccygeal vein puncture to evaluate a complete blood count, serum biochemistry [total protein, albumin, globulin, glucose, cholesterol, triglycerides, urea, gamma-glutamyl transferase (GGT), aspartate aminotransferase (AST), and cholinesterase (ChE)], cytokine levels (proinflammatory interleukins IL-1β and IL-6 and anti-inflammatory IL-10), antioxidant response [thiobarbituric acid reactive substances (TBARS), reactive oxygen species (ROS), total thiol (PSH) and non-protein thiol (NPSH) levels, and gamma-glutamyl transferase (GST) activity], purinergic signaling [adenosine deaminase (ADA) activity, acetylcholinesterase (AChE) activity, ATP, ADP, AMP hydrolysis, and detection of ectonucleotidases CD39 and CD73], and energy metabolism via creatine kinase (CK), pyruvate kinase (PK), and adenylate kinase (AK) activities. Productive performance was assessed through feed intake and milk production. Overall, leukocyte and lymphocyte counts were significantly lower in the FITO group (P ≤ 0.05 and 0.03, respectively). Serum globulin levels tended to increase (P ≤ 0.07), and urea concentration significantly decreased (P ≤ 0.05) in the FITO group. AST enzyme activity was significantly lower (P ≤ 0.02), and ChE enzyme activity was significantly lower in the PHYTO group (P ≤ 0.01). IL-1β and IL-6 levels were significantly lower (P ≤ 0.01), while IL-10 levels were significantly higher (P ≤ 0.02) in the PHYTO-supplemented group. TBARS levels were significantly lower in the PHYTO group (P ≤ 0.05). ROS quantification was significantly lower in the PHYTO group (P ≤ 0.04). NPSH levels were significantly higher in the PHYTO group (P ≤ 0.01). GST concentration was higher in the PHYTO group (P ≤ 0.01). ADA activity in lymphocytes was lower in the PHYTO group (P ≤ 0.01). AChE activity in lymphocytes was higher in the PHYTO group (P ≤ 0.01). NTPDase enzyme activity (ATP and ADP) in platelets was higher in the PHYTO group (P ≤ 0.01). 5'-nucleotidase enzyme activity (AMP) in platelets was higher in the PHYTO group (P ≤ 0.01). ADA activity in platelets was higher in the PHYTO group (P ≤ 0.01). CK enzyme activity was lower in the PHYTO group (P ≤ 0.01), PK activity was lower in the PHYTO group (P ≤ 0.01), and AK enzyme activity was higher in the PHYTO group (P ≤ 0.05). Productive performance was not affected by PHYTO. Phytogenic additives have improved animal health due to their anti-inflammatory, antioxidant, and immunomodulatory activities. Therefore, they may be a promising alternative to reduce metabolic stress during the lactation period. Moreover, there is evidence that phytogenics interfere with cholinergic and purinergic signaling pathways, but their effects on energy metabolism are still not fully understood.