Mixed crude glycerin in laying hen diets: live performance and egg quality and fatty acid profile

Sunflower cake associated with crude glycerin in white laying hens diets: Performance and quality, antioxidant activity and lipid oxidation of eggs

The objective of this study was to evaluate the effects of sunflower cake inclusion and its association with crude glycerin in the diet of laying hens. A total of 320 laying hens with 39 weeks of age were distributed in a completely randomized design in a 4 × 2 factorial scheme with 5 replications of 8 birds. The studied factors were 4 inclusion levels of sunflower cake and 2 levels of crude glycerin. The inclusion of 210 g/kg of sunflower cake reduced egg mass and worsened feed conversion, and after the level 70 g/kg there was reduction in yolk coloration and specific density of eggs with or without the addition of glycerin in the diet. The addition of 70 g/kg of crude glycerin reduced the specific density of eggs in all levels of sunflower cake. There was increase in phenolic compounds, antioxidant capacity and antioxidant activity in eggs and reduction in lipid oxidation of yolks from fresh and stored eggs, with the inclusion of sunflower cake. The addition of crude glycerin increased the lipid oxidation of egg yolks. Therefore, it is possible to include up to 140 g/kg sunflower cake in the diet of laying hens, with or without crude glycerin, without impairing performance and egg quality, obtaining higher antioxidant capacity of eggs and lower lipid oxidation in yolks from fresh and stored eggs. The inclusion of 70 g/kg crude glycerin does not affect laying hens performance, however, it worsens shell quality and increases lipid oxidation in the liver and egg yolks.

Productive performance, egg quality, and hatching traits of Japanese quail reared under different levels of glycerin

This study evaluated subsequent effects of glycerin on productive performance, egg quality, and hatching traits in Japanese quail. A total of 200 birds was arranged according to a completely randomized design into 5 treatment groups having 5 replicates of 8 birds each (6 females and 2 males). Treatments consisted 5 levels of glycerin, i.e., 2.5, 5, 7.5, and 10% and the control group. Birds were fed with different levels of glycerin during a rearing period of 6 wk and their subsequent effects on productive performance, egg quality, and hatching traits were observed. Data were collected regarding productive performance for 16 wk; however, egg quality and hatching traits were recorded during pre-peak (at fourth wk), peak (at 12th wk), and post peak (at 16th wk) phase. Productive performance, egg quality, and hatching traits did not differ significantly throughout the experimental period. It was concluded that glycerin can be used as a replacement energy source, having no effect on productive and reproductive performance in Japanese quail.

The effect of replacing soya bean oil with glycerol in diets on performance, egg quality and egg fatty acid composition in laying hens

The objective of this experiment was to replace soya bean oil with glycerol in laying hen diets and assess the change's effect on performance, parameters of egg quality and the egg fatty acid profile. A total of 60 44-week-old Hy-Line W36 laying hens were distributed according to a completely randomised experimental design into four treatments consisting of glycerol substitutions for soya bean oil dietary at varying inclusion levels (0%, 25%, 50% and 75%), with five replicates of three birds each. Dietary treatments had no significant effect on BW change, egg production, feed intake, feed conversion ratio, egg weight and egg mass of laying hens. The inclusion of glycerol in the diet of laying hens had no significant effect on egg specific gravity, eggshell breaking strength, eggshell weight, eggshell thickness, egg shape index, albumen index, yolk index, haugh unit, albumen pH, yolk pH and egg yolk colour values. The inclusion of glycerol in the diet of laying hens had no significant effect on palmitic, palmitoleic, stearic, oleic and linolenic acid contents of the egg yolk. The linoleic acid and polyunsaturated fatty acid contents of the egg yolk significantly decreased with the higher levels of dietary glycerol supplementation (P<0.05). The results of this study show that it is possible to replace 75% of soya bean oil (4.5% in diet) with glycerol.