Efficacy of Dietary Supplementation with Zinc-Chromium Mixture, Organic Selenium, or Their Combinations on Growth Performance, Carcass Traits, and Blood Profiles of Broilers under Heat Stress Conditions

SIMPLE SUMMARY: The need for methods to lessen the impacts of heat stress has increased due to climate change. The addition of trace elements to the food of chicks is an approach used to enhance production yield while boosting grill productivity. In livestock production, selenium is a crucial trace mineral for improved performance, physiological state, and health advantages. Numerous studies have examined the advantages and uses of both organic and inorganic selenium in poultry feeding. On the other hand, there is a dearth of knowledge on the use of organic selenium in heat-stress situations. In this work, we assessed the impact of dietary organic selenium on broiler growth performance, carcass characteristics, and blood profiles under heat stress, with or without a zinc-chromium mixture. According to the findings, adding organic selenized yeast improves the haematological, biochemical, and antioxidant status of broilers as well as their productivity. The weights and carcass qualities of the birds given Zn-Cr plus low or high Se levels were improved. In light of this, we concluded that the combined effect of feed additives (Zn-Cr and organic-Se) could reduce the effects of heat stress on broilers by increasing metabolic processes and enhancing growth performance. ABSTRACT: To determine the effects of organic selenium (0.0–0.6 mg and 0.9 mg Se/Kg diet) and Zn-Cr mixture (100 mg Zn/Kg diet plus 1.5 mg Cr/Kg diet) on broiler chicken performance, carcass traits, blood hematology, and biochemistry under heat stress conditions, this study was conducted. Under temperatures between 30.21 to 31.82 °C, 240 broiler chickens (Ross-308), which were 7-day-old, were randomly assigned to one of six treatments: T1 (control), T2 (100 mg Zn per kg of diet and 1.5 mg Cr per kg of diet), T3 (0.6 mg Se per kg of diet), T4 (0.9 mg Se per kg of diet), T5 (100 mg Zn, 1.5 mg Cr and (LSe), and T6 (100 mg Zn, 1.5 mg Cr and (HSe)). At 35 days old, the chicks fed a diet containing Zn-Cr with low or high organic selenium (organic-Se) outweighed the control group in terms of live body weight, weight gain, and feed conversion ratio (p < 0.05). In comparison to the control treatment, birds fed diets supplemented with Zn-Cr or organic-Se (LSe, HSe) significantly increased their serum levels of total protein and total antioxidant capacity. However, these additives resulted in a decrease (p < 0.01) in their serum levels of triglycerides, total cholesterol, low-density lipoprotein (LDL) cholesterol, creatinine, and uric acid. Together, it was found that trace elements (Zn-Cr and organic-Se) may greatly lessen the impacts of heat stress on broilers by promoting growth performance and boosting metabolic processes.