Assessing serum metabolite profiles as predictors for feed efficiency in broiler chickens reared at geographically distant locations

Abstract

1. The objective of this study was to investigate differences in growth performance, serum intermediary metabolites, acute-phase proteins and white blood cells in low, medium and high-residual feed intake (RFI) chickens. It was also assessed if the environment affects the feed efficiency (FE) and FE-related performance and serum profiles of chickens. 2. Individual body weight (BW) and feed intake (FI) were recorded from d 7 of life. At 5 weeks of age, female and male broiler chickens (Cobb 500) were selected according to their RFI (L1: Austria; L2: UK; n = 9/RFI group, sex and locatity -45on) and blood samples were collected. 3. Chickens at L1 had similar FI but a 15% higher BW gain compared to chickens at L2. The RFI values of female chickens were -231, 8 and 215 g and those of male chickens -197, 0 and 267 g for low, medium and high RFI, respectively. 4. Location affected serum glucose, urea, cholesterol, non-esterified fatty acids (NEFA) and ovotransferrin in females, and serum glucose and triglycerides in male chickens. Serum uric acid and NEFA linearly increased from low to high RFI in females, whereas in males, cholesterol showed the same linear response from low to high RFI. Serum alpha-1-acid glycoprotein and blood heterophil-to-lymphocyte ratio linearly increased by 35% and 68%, respectively, from low to high RFI but only in male chickens at L1. 5. Regression analysis showed significant positive relationships between RFI and serum uric acid (R = 0.49) and cholesterol (R = 0.13). 6. It was concluded that RFI-related variation in serum metabolites of chickens was largely similar for the two environments and that serum metabolite patterns could be used to predict RFI in chickens.

Feed Restriction Modulates the Fecal Microbiota Composition, Nutrient Retention, and Feed Efficiency in Chickens Divergent in Residual Feed Intake

“…The RFI rank related differences in feed intake were detectable in ad libitum fed females, with low RFI females having a 432 g lower TFI than high RFI females as indicated by the restrictive feeding × RFI interaction ( P = 0.010; Table 1 ), but not in ad libitum fed males. The feed amount provided to the restrictively fed chickens was calculated to represent a feed restriction of about 90–95% of ad libitum feeding using the feed intake data from a previous trial using the same chicken genetic and dietary composition (Metzler-Zebeli et al, 2017 , 2018 ; Siegerstetter et al, 2017 ). Across both sexes, restrictively fed chickens ate 338 g less between 9 and 30 dph than ad libitum fed chickens ( P < 0.001).…”

“…Across both sexes, restrictively fed chickens ate 338 g less between 9 and 30 dph than ad libitum fed chickens ( P < 0.001). Because low RFI chickens commonly eat less than high RFI chickens (Metzler-Zebeli et al, 2017 ), the feed restriction was less severe in the low RFI chickens (92% of ad libitum group) compared to the high RFI chickens (80% of ad libitum group). Furthermore, across both sexes, restrictively fed chickens gained 231.5 g less weight between 9 and 30 dph than their ad libitum fed counterparts ( P < 0.001).…”

Fecal Microbiota Transplant From Highly Feed Efficient Donors Affects Cecal Physiology and Microbiota in Low- and High-Feed Efficient Chickens

“…Differences in intestinal electrophysiological parameters and permeability marker flux rates were evaluated for four chickens per sampling day (Metzler-Zebeli et al, 2017, 2018b). This resulted in five observations per RFI and inoculum group.…”

“…After recording electrophysiological measurements for 5 min, fluorescein 5(6)-isothiocyanate (FITC; 389.38 g/mol; Sigma-Aldrich, Schnelldorf, Austria) and horse-radish peroxidase (HRP; 44,000 g/mol; Carl Roth GmbH + Co. KG, Karlsruhe, Germany) were added to final concentrations of 0.1 m M and 1.8 μ M to the mucosal side, respectively, to assess the mucosal-to-serosal flux (Metzler-Zebeli et al, 2018b). The glucose absorptive tissue response was studied by adding glucose to a final concentration of 10 mmol/L to the buffer at the mucosal side at 45 min after short-circuiting the tissue (Metzler-Zebeli et al, 2017). The chemical effect on glucose transporter function was measured by comparing the I sc and R T for 1 min before glucose was added to the peak current and resistance response of the exposed tissue (ΔI sc and ΔR T ) obtained within 2 min after the addition of glucose.…”

Feed Restriction Reveals Distinct Serum Metabolome Profiles in Chickens Divergent in Feed Efficiency Traits

“…Understanding the mechanisms that underlie individual animal variation is therefore essential for the development of strategies to improve the FE in poultry. Serum intermediary metabolites, i.e., uric acid and cholesterol, may be used as FE predictors [4] in that they support FE-related differences in nutrient assimilation, and hepatic, muscle, and adipocyte metabolism [5]. Similar differences in serum profiles were reported for the restrictive feeding of chickens, which has the goal of preventing metabolic diseases, such as fatty liver, and reduce abdominal fat accretion [6].…”