Comparative Effects on Using Bilberry Leaves in Broiler Diet Reared under Thermoneutral Conditions vs. Heat Stress on Performance, Health Status and Gut Microbiota

Abstract

The study aims to investigate the impact of dietary bilberry leaves on the performance, health status, and gut microbiota of broilers reared in both thermoneutral conditions and under heat stress. Sixty Cobb 500 broiler chicks were divided into two groups (C-TN, BL-TN) and reared in thermoneutral conditions for the first trial. For the second trial, two other groups (C-HS and BL-HS) were reared in heat stress (32 °C), with 30 chickens in each group. The experimental diets were supplemented with 1% bilberry leaves compared to the control diets. The broilers fed a diet with bilberry leaves had lower levels of cholesterol compared to the control birds. At the end of the experiment, six broilers per group were slaughtered, and intestinal contents were collected for bacteriological analyses. The results revealed that bilberry leaves increased body weight and average daily feed intake in the BL-TN group compared to the C-HS group. However, the broilers fed a bilberry leaves diet and reared in heat stress had a significantly lower average daily feed intake and average daily weight gain than the C-TN group. Additionally, the number of staphylococci colonies decreased significantly in the group fed with a BL-supplemented diet and reared in TN compared to C-TN, while lactobacilli increased significantly in BL-TN compared to C-TN. In summary, bilberry leaves can be used as a natural supplement in a broiler’s diet to regulate serum cholesterol in heat stress and maintain the health of intestinal microflora in thermoneutral conditions.

Comparative Analysis of Black Chokeberry (Aronia melanocarpa L.) Fruit, Leaves, and Pomace for Their Phytochemical Composition, Antioxidant Potential, and Polyphenol Bioaccessibility

“…The scavenging activity of samples against ABTS •+ was determined using a method that relied on the interaction between an antioxidant and pre-generated ABTS •+ radical cation in accordance with the guidelines set forth by Saracila et al [ 27 ]. The absorbance of samples against a blank was read at 734 nm using a microplate reader Varioskan Lux (Thermo Fischer Scientific Waltham, MA, USA).…”

“…The methodology for the determination of the chelating effect on ferrous ions was adapted from the method described by Sabeena Farvin et al [ 28 ] and Santos et al [ 29 ] with slight modifications [ 27 ]. The Varioskan Lux microplate reader (Thermo Fisher Scientific, Waltham, MA, USA) was used to measure the absorbance of the purple color of the complex formed when an extract competed with ferrozine for ferrous ions against the blank at 562 nm.…”

“…The antioxidant activity of each sample is expressed as millimoles of Trolox equivalents (TE) per kilogram of sample. The percentage inhibition was calculated using the following formula: The scavenging activity of samples against ABTS •+ was determined using a method that relied on the interaction between an antioxidant and pre-generated ABTS •+ radical cation in accordance with the guidelines set forth by Saracila et al [27]. The absorbance of samples against a blank was read at 734 nm using a microplate reader Varioskan Lux (Thermo Fischer Scientific Waltham, MA, USA).…”