ArticleAnimal bioscience2026
Effect of age on eggshell color and Haugh unit of eggs, protoporphyrin IX and ovomucin deposition and related gene expression in Hyline Brown laying hens.
Article in Animal bioscience, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
0 citing papers in PubMed.
No citing paper in PubMed yet.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
5 authors.
Funding
Abstract
objectiveThis study was conducted to investigate the effects of age on eggshell color, Haugh unit, and underlying mechanism in Hyline Brown laying hens.
methodsA total of 192 Hyline Brown laying hens at 165 (D165 group), 307 (D307 group), or 475 (D475 group) days of age were divided into 3 groups with 8 replicates of 8 birds each, and fed the same diet for three weeks.
resultsCompared to the D165 group, the D307 and D475 groups had higher (p<0.05) eggshell L* value and yolk ratio but lower (p<0.05) albumin ratio; the D475 group had higher (p<0.05) eggshell b* value but lower (p<0.05) albumin height, Haugh unit and eggshell a* value. The D165 group had higher (p<0.05) eggshell protoporphyrin IX content and ovomucin content in eggs than the D307 and D475 groups. The D165 group showed higher (p<0.05) total superoxide dismutase activity and glutathione content in eggshell gland compared to the D307 group. The malondialdehyde contents in serum, eggshell gland and magnum were higher in the D475 group than in the D165 group (p<0.05). The D307 and D475 groups had lower (p<0.05) mRNA levels of genes related to pigment synthesis and transport (coproporphyrinogen oxidase, aminolevulinic acid synthase-1 and ATP-binding cassette subfamily G member 2) than the D165 group. The D475 group had lower (p<0.05) mRNA levels of genes related to albumin synthesis (α-ovomucin and lysozyme) than the D165 and D307 groups.
conclusionAs hens aged, the deterioration of eggshell color and Haugh unit of eggs resulted from decreased gene expression and secretion of protoporphyrin IX and ovomucin, which could be attributed to increased lipid peroxidation in eggshell gland and magnum.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.