Contents lists available at ScienceDirect Research in Veterinary Science journal homepage: www.elsevier.com/locate/rvsc Feed addition of curcumin to laying hens showed anticoccidial effect, and improved egg quality and animal health Gabriela M. Galli a , Aleksandro S. Da Silva a,b, ⁎ , Angelisa H. Biazus b , João H. Reis a , Marcel M. Boiago a,b , Josué P. Topazio a , Marcos J. Migliorini b , Naiara S. Guarda c , Rafael N. Moresco c , Aline F. Ourique d , Cayane G. Santos d , Leandro S. Lopes e , Matheus D. Baldissera f , Lenita M. Stefani a,b a Department of Animal Science, Universidade do Estado de Santa Catarina (UDESC), Chapecó, SC, Brazil b Graduate Program of Animal Science, UDESC, Chapecó, SC, Brazil c Department of Clinical and Toxicological Analysis, Universidade Federal de Santa Maria (UFSM), Brazil d Graduate Program of Nanoscience, Centro Universitário Franciscano, Brazil e Department of Veterinary Medicine, Universidade Federal de Minas Gerais (UFMG), Brazil f Department of Microbiology and Parasitology, UFSM, Brazil ARTICLE INFO Keywords: Curcuma longa Laying hens Egg quality Protozoan Eimeria sp. ABSTRACT The aim of this study was to evaluate whether the addition of curcumin in the diet of commercial laying hens could have an anticoccidial action and improve egg quality. For this, 60 laying hens were divided into three groups: T0 (the control group); T30 and T50 (30 and 50 mg/kg of curcumin in the feed, respectively). Eggs recently laid were collected on days 14 and 21 of the experiment, and stored for 21 days. It was observed increased specific gravity and yolk index in stored eggs of the groups T30 and T50 compared to T0. The yolk color reduced in the eggs stored from groups T30 and T50 compared to T0. Moreover, TBARS levels were lower in fresh and stored eggs from groups T30 and T50. It was observed increased TAC levels in fresh eggs from groups T30 and T50 and in stored eggs from the group T50. The presence of curcumin was not detected by HPLC in the yolk and albumen. Seric levels of albumin and uric acid did not differ between groups, while seric levels of total proteins increased on day 21 on groups T30 and T50. Finally, it was observed a significant reduction on the number of oocysts in fecal samples on days 14 and 21 of T30 and T50 compared to T0. Based on these evidences, it is possible to conclude that the addition of curcumin in the diet of laying hens has an anticoccidial effect and improves egg quality. 1. Introduction The worldwide poultry industry remains very strict regarding the use of chemicals to treat diseases or to promote animal growth, re- sulting on food products of great quality and safe to consumers. It is important to emphasize that eggs with high quality and safety certifi- cation increase consumer's confidence, contributing to the increase of consumption, and thus, leading to market expansion and poultry farming development (Mazzuco, 2016). The use of feed additives to reach maximum animal efficiency in order to control pathogens and to improve performance is considered an indispensable technique in poultry farming (Nunes et al., 2012). More- over, the use of additives can improve important characteristics linked to egg quality such as: egg weight, eggshell strength and yolk color, that are considered important features for producers, industry and consumers (Trindade et al., 2007). Due to many characteristics, the egg is con- sidered a complete food and an excellent source of fatty acids, vitamins, minerals and essential amino acids. The internal egg quality depends on preservation, feed composition, and alterations on these factors may also affect egg quality, since animal feed affect directly the yolk lipid stability (Yesilbag et al., 2013) and high temperatures leads to yolk oxidation (Hayat et al., 2010). In order to improve the oxidative stability of chicken eggs, the use of antioxidant substances in the diet of laying hens have been considered a promising approach (Yesilbag et al., 2013). The use of antibiotics, chemotherapeutic agents and vaccines are the most used additives in poultry rations, but they have high costs and https://doi.org/10.1016/j.rvsc.2018.01.022 Received 6 November 2017; Received in revised form 14 January 2018; Accepted 21 January 2018 ⁎ Corresponding author at: Animal Science Department, Universidade do Estado de Santa Catarina (UDESC), Santo Antônio, Beloni Trombeta Zanin Street, 680E, zip code 89815-630, Chapecó city, SC, Brazil. E-mail address: aleksandro.silva@udesc.br (A.S. Da Silva). Research in Veterinary Science 118 (2018) 101–106 0034-5288/ © 2018 Elsevier Ltd. All rights reserved. T