RETRACTED ARTICLE: Effects of dietary glycerol monolaurate on productive performance, egg quality, serum biochemical indices, and intestinal morphology of laying hens

Abstract

Glycerol monolaurate (GML) has been widely used as an effective antibacterial emulsifier in the food industry. A total of 360 44-week-old Hy-Line brown laying hens were randomly distributed into four groups each with six replicates of 15 birds, and fed with corn-soybean-meal-based diets supplemented with 0, 0.15, 0.30, and 0.45 g/kg GML, respectively. Our results showed that 0.15, 0.30, and 0.45 g/kg GML treatments significantly decreased feed conversion ratios (FCRs) by 2.65%, 7.08%, and 3.54%, respectively, and significantly increased the laying rates and average egg weights. For egg quality, GML drastically increased albumen height and Haugh units, and enhanced yolk color. Notably, GML increased the concentrations of polyunsaturated and monounsaturated fatty acids and reduced the concentration of total saturated fatty acids in the yolk. The albumen composition was also significantly modified, with an increase of 1.02% in total protein content, and increased contents of His (4.55%) and Glu (2.02%) under the 0.30 g/kg GML treatment. Additionally, GML treatments had positive effects on the lipid metabolism of laying hens, including lowering the serum triglyceride and total cholesterol levels and reducing fat deposition in abdominal adipose tissue. Intestinal morphology was also improved by GML treatment, with increased villus length and villus height to crypt depth ratio. Our data demonstrated that GML supplementation of laying hens could have beneficial effects on both their productivity and physiological properties, which indicates the potential application of GML as a functional feed additive and gives us a new insight into this traditional food additive.

Effect of Dietary Medium-Chain α-Monoglycerides on the Growth Performance, Intestinal Histomorphology, Amino Acid Digestibility, and Broiler Chickens’ Blood Biochemical Parameters

“…Liu et al [ 51 ] reported an increase in the jejunal villus length and VH: CD ratio in the duodenum and ileum by dietary GML. Zhao, et al [ 69 ] reported improved Intestinal morphology by GML supplementation indicated by increased VH and VH: CD ratio. Liu, et al [ 70 ] reported improved growth, muscle amino acids, and intestinal morphology in broilers by GML supplementation (300, 450, and 600 mg/kg) mostly by influencing the gut microbiota function and community.…”

“…Consequently, an increase in de novo fatty acid synthesis may cause a rise in the production of triglycerides [ 77 ]. Saeidi et al [ 43 ] reported that quail chicks fed on MCFA-supplemented diet showed decreased serum levels of TC, TG, LDL-C, and increased HDL-C. Zhao et al [ 69 ] reported an optimistic effect of GML supplementation on the lipid profile of laying hens indicated by reducing the the serum TG and TC levels and lowering the abdominal fat.…”

Effects of α-glyceryl monolaurate on growth, immune function, volatile fatty acids, and gut microbiota in broiler chickens

“…(2019) found that GML treatment may improve growth performance, reduce numbers of parasite oocysts and E. coli , and augment the production of globulins, while leaving meat quality unaltered. Moreover, Zhao et al. (2019) showed that dietary GML improved egg quality.…”

“…Recent studies have shown that GML can be used as a feed additive to improve animal growth performance and health ( Fortuoso et al., 2019 ; Zhao et al., 2019 ). Fortuoso et al.…”

Retraction Note to: Effects of dietary glycerol monolaurate on productive performance, egg quality, serum biochemical indices, and intestinal morphology of laying hens

“…The authors have retracted this article (Zhao et al, 2019) due to significant overlap with a previously published Chinese language article (Liu et al, 2017), including overlap in Table 1, Table 2, Table 3, Table 6, Fig. 4, and part of the results (Sections 3.1, 3.2, 3.5, and 3.7).…”