A P Zepeda-Velazquez1, J C Angeles-Hernandez1, A H Ramirez-Perez2, V Ambriz-Vilchis3, C J Alvarez-Alonso4, O Del Razo1, G Plata-Perez1, F R Ortega-Meneses1
1Instituto de Ciencias Agropecuarias, Universidad Autonoma Del Estado De Hidalgo; 2Facultad de Medicina Vterinaria, Universidad Nacional Autonoma de Mexico; 3Biosimetrics Ltd. SRUC Building; 4Colegio Superior Agropecuario del Estado de Guerrero
Several management practices can have deleterious effects in the poultry industry. High population densities and failure to maintain a stable temperature in the shed can affect performance variables such as: feed intake, weight gain and mortality rate. Selenium (Se) is a potent antioxidant as is a structural part of glutathione peroxidase (GPx). Therefore, Se dietary supplementation can aid to diminish oxidative stress under heat stress conditions. The aim of the present study was to evaluate the effect of SE supplementation on performance and antioxidant status of broilers under heat stress, by means of a systematic review of the literature. The review included a database of 74 trials that met the follow inclusion criteria: published research articles that report effect and sample size and variability and random procedure The response variables were: GPx and malondialdehyde (MDA) levels, dry matter intake, average daily gain, feed conversion rate (FCR) and mortality rate (MOR); and as explicative variables: broiler´s line, Se source and dosage, heat stress level (HSL), days of experimentation, sample source (blood, liver or meat) and basal Se level. All statistical analysis were carried out in R software (R Core Team, 2018), using the “meta” and “Metafor” packages for meta-analysis and meta-regression, respectively. Higher levels of GPx were found in Se supplemented broilers (>1.73; P=0.001). However, the response level was also related to: HSL, dosage, Se source and source of sample. Higher effect size was founded in supplementation with inorganic Se sources (2.92) in comparison with organic and nano Se sources (1.66 and 1.44, respectively). MDA, FCR and MOR levels were significantly lower in supplemented broilers (<0.35μmol/ml, <0.02g/g and -6.11%, respectively). The heterogeneity of all variables decreased when the explicative variables were included in the mixed-regression model. Our findings reveal that Se supplementation improved broiler´s antioxidant status, performance and reduce the mortality.
Young researcher specialized in broiler production focus mainly in health and nutrition.