Evidence map›Paper›PMID 41495431›Full record

ArticleJournal of animal science2026

Laying hen responses to balanced protein reduction on performance, egg quality, nitrogen balance, and fat and mineral utilization.

Elijah Ogola Oketch, Myunghwan Yu, Shan Randima Nawarathne, Nuwan Chamara Chathuranga, Jeseok Lee, Haeeun Park, Bo Keun Lee, Kwan Eung Kim, Jung Min Heo

Abstract read
In one paragraph

Article in Journal of animal science, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

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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

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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

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0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

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5 · Who and what money

Authors and funding

9 authors.

Elijah Ogola OketchDepartment of Animal Science and Biotechnology, Chungnam National University, Daejeon, 34134, Republic of Korea.
Myunghwan YuDepartment of Animal Science and Biotechnology, Chungnam National University, Daejeon, 34134, Republic of Korea.
Shan Randima NawarathneDepartment of Animal Science and Biotechnology, Chungnam National University, Daejeon, 34134, Republic of Korea.
Nuwan Chamara ChathurangaDepartment of Animal Science and Biotechnology, Chungnam National University, Daejeon, 34134, Republic of Korea.
Jeseok LeeDepartment of Animal Science and Biotechnology, Chungnam National University, Daejeon, 34134, Republic of Korea.
Haeeun ParkDepartment of Animal Science and Biotechnology, Chungnam National University, Daejeon, 34134, Republic of Korea.
Bo Keun LeeNonghyup Feed Inc, Seoul, 05398, Republic of Korea.
Kwan Eung KimNonghyup Feed Inc, Seoul, 05398, Republic of Korea.
Jung Min HeoDepartment of Animal Science and Biotechnology, Chungnam National University, Daejeon, 34134, Republic of Korea.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

The effect of graded reductions in balanced crude protein (CP) on hen productive performance, egg quality, nitrogen balance, abdominal fat deposition, tibia traits, and relative economic outcomes from 26 to 44 wk of age (WOA) was investigated. A total of 252 26-wk-old Hy-Line Brown hens were housed in enriched cages (seven birds/cage) and randomly allocated to one of four different dietary CP levels of iso-energetic diets with nine replicates per treatment. The trial was conducted over two phases of 26 to 34 and 36 to 44 WOA. Diets included a high-protein (HP; 18.0% and 17.0% CP in Phases 1 and 2), medium-protein (MP), low-protein (LP), and very low-protein (VLP) series, representing stepwise reductions of 0.50, 1.00, and 1.50 percentage points relative to HP. Limiting amino acids (AA; lysine, methionine, and threonine) were supplemented to ensure balanced AA profiles. Collected data were analyzed using the general linear model (GLM) procedure for one-way ANOVA; statistical significance was set at P < 0.05, and trends were noted at 0.05 < P < 0.10. Balanced protein reduction tended to improve abdominal fat contents (2.66% to 2.85%; P = 0.059), but reduce body weight gain (141.66 to 95.66 g; P = 0.089), particularly with the VLP diet. Across 26 to 44 WOA, graded CP reduction lowered egg weight (60.36 to 59.40 g; P < 0.05) and feed conversion efficiency (1.93 to 1.97 g feed/g egg; P < 0.05); and tended to reduce egg mass (57.02 to 55.11 g/hen/day; P = 0.080), particularly in the VLP group. As to egg quality, Haugh units were higher (P < 0.05) with HP and MP diets (94.60 and 94.30) than LP and VLP diets (93.66 and 93.04) across 26-44 WOA. In contrast, LP and VLP diets tended to improve yolk color (8.38 to 8.49; P = 0.076) and egg-breaking strength (5.39 to 5.51 kg; P = 0.058) across 26-44 WOA. Dietary CP reduction linearly reduced nitrogen consumed and excreted by more than 10% (P < 0.05). Tibia-breaking strength tended to decline with dietary CP reduction (P = 0.094), decreasing from 27.62 kg in HP to 25.54-25.68 kg in the LP and VLP diets. Economically, reduced CP lowered egg income (P < 0.05) at weeks 34 and 44 (2.00 to 1.77$; 1.96 to 1.89$, respectively); and feed costs at week 34 only (0.54 to 0.52$; P = 0.088), but profit margins remained unaffected (P > 0.10). Conclusively, these results confirm the effectiveness of balanced dietary protein reduction in maintaining egg production rate and most egg quality traits while reducing nitrogen excreted and feed costs.

Indexed as

ChickensDietary ProteinsDiet, Protein-RestrictedEggsMineralsNitrogenAnimal FeedAnimal Nutritional Physiological PhenomenaAnimalsDietFemaleOvumRandom AllocationDietary ProteinsMineralsNitrogenabdominal fategg qualitylaying performancenitrogen excretionproteintibia

Identifiers

PMID41495431
PMCPMC12903949

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LicenceCC BY
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Registered trials

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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.