Evidence map›Paper›PMID 41414841›Full record

ArticleAnimal bioscience2026

Nitrogen balance and yolk corticosterone levels of laying hens fed low-protein diets from 33 to 64 weeks of age.

Sunhoo Moon, Yun-Ji Heo, Jina Park, Da-Hye Kim, Kyung-Woo Lee

Abstract read
In one paragraph

Article in Animal bioscience, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

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.

2 · The registry

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.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors.

Sunhoo MoonDepartment of Animal Science and Technology, College of Life Sciences, Konkuk University, Seoul, Korea.
Yun-Ji HeoDepartment of Animal Science and Technology, College of Life Sciences, Konkuk University, Seoul, Korea.
Jina ParkDepartment of Animal Science and Technology, College of Life Sciences, Konkuk University, Seoul, Korea.
Da-Hye KimDepartment of Animal Science and Technology, College of Life Sciences, Konkuk University, Seoul, Korea.
Kyung-Woo LeeDepartment of Animal Science and Technology, College of Life Sciences, Konkuk University, Seoul, Korea.

Funding

Korean Institute of Planning and Evaluation for Technology in Food, Agriculture and ForestryMinistry of Agriculture, Food and Rural Affairs 321080-03-3-HD020
6 · The paper itself

Abstract

objectiveThe study aimed to investigate the effects of varying dietary crude protein levels on laying performance, nitrogen balance, odor emission, and yolk corticosterone in laying hens from 33 to 64 weeks.

methodsTwo hundred and forty laying hens (Hy-Line Brown) were randomly assigned to one of four varying protein diets from 18.5% to 12.5% at 33-45 weeks, from 18.0% to 12.0% at 46 to 55 weeks, and from 17.0% to 11.0% at 56 to 64 weeks.

resultsLaying performance (i.e., egg weight, egg production, and egg mass, p<0.05) was linearly declined with decreasing dietary crude protein levels. Eggshell thickness decreased (quadratic effect, p = 0.033) at 44 weeks of age, while increased (linear effect, p<0.001) at 52 weeks of age as dietary protein levels lowered. Decreasing dietary protein levels linearly increased (p<0.05) Haugh unit at 52 and 64 weeks. Apparent digestibility of dry matter and crude protein increased at 45 and 55 weeks of age as dietary protein levels decreased. Lowering dietary protein levels increased the concentration of high-density lipoprotein cholesterol (linear effect, p = 0.012) but decreased (linear effect, p = 0.021) uric acid levels in serum samples at 64 weeks of age. Nitrogen excretion linearly declined as dietary protein levels decreased at all ages. Among the odors analyzed, fecal volatile fatty acids increased at 55 weeks of age with decreasing dietary protein levels. Finally, yolk corticosterone was not altered by dietary protein levels during the laying cycle.

conclusionIt is concluded that decreasing dietary protein levels fortified with limiting amino acids can be applied to mitigate nitrogen excretion without affecting nutritionmediated stress in laying hens.

Indexed as

CorticosteroneEgg ProductionLaying HenLow ProteinNitrogen Excretion

Identifiers

PMID41414841
PMCPMC13175073

What Socratic holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

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 Socratic graph.