Evidence map›Paper›PMID 42537379›Full record

ArticlePoultry science2026

Effect of photoperiod duration during incubation on hatch traits, growth, and behavior of Leghorn chicks to 21 days of age.

Celma E Ferreira Dos Santos, Tory Shynkaruk, Eugenia Herwig, Bruce Rathgeber, Trever G Crowe, Henry L Classen, Karen Schwean-Lardner

Abstract read
In one paragraph

Article in Poultry 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.

0numbers the graph read from it
0cells of the map it votes in
0citing 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

0 citing papers in PubMed.

No citing paper in PubMed yet.

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

7 authors.

Celma E Ferreira Dos SantosDepartment of Animal and Poultry Science, University of Saskatchewan, Saskatoon, Canada.
Tory ShynkarukDepartment of Animal and Poultry Science, University of Saskatchewan, Saskatoon, Canada.
Eugenia HerwigEgg Farmers of Canada, ON, Canada.
Bruce RathgeberDepartment of Animal Science and Aquaculture, Dalhousie University, NS, Canada.
Trever G CroweDepartment of Mechanical Engineering, University of Saskatchewan, Saskatoon, SK, Canada.
Henry L ClassenDepartment of Animal and Poultry Science, University of Saskatchewan, Saskatoon, Canada.
Karen Schwean-LardnerDepartment of Animal and Poultry Science, University of Saskatchewan, Saskatoon, Canada. Electronic address: karen.schwean@usask.ca.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

This study determined the effects of photoperiod duration during incubation on Lohmann LSL-Lite hatch traits, growth, and behavior. Eggs (n = 1,200) were randomly assigned to one of four treatments: 0L:24D (0L), 6L:18D (6L), 12L:12D (12L), or 18L:6D (18L). Light was provided via red (641 nm) LED lamps. Data were analyzed using a one-way ANOVA in a randomized complete block design with significance declared when P < 0.05. In-ovo photoperiod did not affect embryo mortality, hatchability, or hatch window. However, 5, 10, 25, 50, 75, and 90% of the eggs hatched earlier in the 18 L treatment compared to 0 L. Male chicks in the 0 L treatment were heavier than males from 12 or 18 L. Female chicks in the 0 L treatment were heavier than females from 6, 12, or 18 L. Treatment did not affect navel closure, female body length, heterophil/lymphocyte (H/L) ratio, composite asymmetry, or relative yolk-free BW and yolk sac residue. Relative weights of liver, heart, duodenum, ileum, and cecum were heaviest under 18 L. During rearing, BW was higher in the 0 L birds compared to 6 and 18 L at 7 d, 6 and 12 L at 14 d, and 18 L at 21 d, however, flock uniformity was unaffected. No effects were observed on composite asymmetry or H/L ratio at 21 d post-hatch. At 0 d, chicks incubated under 18 L spent a higher percentage of time running and a lower percentage of time resting. At 1 d, chicks in the 18 L treatment spent more time resting, walking, and foraging than those incubated under 0 L. At 2 d, chicks in the 18 L treatment spent a lower percentage of time resting and higher percentage of time foraging compared to 0 L. By 3 d, only standing behaviour was affected with chicks in the 6 L treatment standing for a higher percentage of time than chicks in the 0 and 12 L treatments. In conclusion, the use of photoperiods during incubation impacted duration of incubation without negatively affecting the development of the embryo or pullet stress and behaviour.

Indexed as

Chick qualityHatch windowIn-ovoPhotostimulationStress

Identifiers

PMID42537379
PMCPMC13452207

What OpenQuestion holds

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LicenceCC BY-NC-ND
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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.