The Antioxidative Impact of Dietary Vinegar and Rocket Salad on the Productivity, Serum Oxidation System, and Duodenal Histology of Chickens

SIMPLE SUMMARY: Oxidative stress (OS) is detrimental to the production of reactive oxygen species. It affects poultry performance, health status, welfare, and meat and eggs quality. Many methods of reducing oxidative stress have been considered; however, due to the birds’ welfare and the consumers’ safety, natural substances (antioxidants) have mainly been taken into consideration. The current data show that feeding broiler chickens Ross 308 with either a dietary supplementation of vinegar (5 and 10 mL/kg of diet) or rocket salad (2 and 3 g/kg of diet) could mitigate the experimentally induced oxidative stress level. Positive changes were demonstrated by the improvement of the serum oxidation system, which led to increases in the birds’ productivity and carcass quality, and modulations of intestine histomorphological characteristics. Thus, vinegar and rocket salad might be promising natural alternatives for costly feed additives under the various types of stresses or acute environmental conditions. ABSTRACT: The purpose of the study was to investigate the ameliorative effect of dietary rocket salad and apple cider vinegar on the oxidative stress (OS) status of broilers. Specifically, 720 Ross 308 chicks were divided into six groups: negative and positive controls (NC and PC with and without additives, Vi1 and V12 experimental groups fed with diets mixed with 5 and 10 mL of vinegar/kg, and Ro1 and Ro2 groups fed with diets mixed with 2 and 3 g of rocket salad/kg, respectively). The experimental groups Vi1 and Vi2 were fed with feed mixture moisturized with 5 and 10 mL of vinegar/kg, and Ro1 and Ro2 were fed with 2 and 3 g of rocket salad/kg, respectively. The birds’ productivity, oxidative serum parameters, and morphometric indices of the gastrointestinal tract were registered at 6 weeks of rearing. The vinegar or rocket salad additive had powerful potentials to significantly suppress (p ≤ 0.05) OS through improving the birds’ survivability, body weight gain, feed conversion ratio, and carcass yield. The highest villus height and villus height/crypt depth ratio of the duodenum were achieved by Vi2, Ro1-2, and NC (p ≤ 0.05). The villus surface area and muscular layer thickness were smallest in the PC, while they did not differ significantly in other groups (p > 0.05). Similar relationships were found in serum superoxide dismutase, glutathione peroxidase, hydroperoxide, and malondialdehyde; however, higher doses of both additives were more effective. It seems that liquid vinegar and rocket salad could have beneficial influences on the antioxidant status of birds.