Evidence map›Paper›PMID 42747726›Full record

ArticleVeterinary research communications2026

Anatomy, histology, and histochemistry of the harderian and lacrimal glands in the great spotted woodpecker (dendrocopos major).

Joanna Klećkowska-Nawrot, Aleksandra Kroczak-Zdańkowska, Adam Urantówka, Grzegorz Zaniewicz, Shaw Badenhorst, Aleksander Chrószcz, Krzysztof Stegmann, Karolina Barszcz, Dominik Poradowski

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Article in Veterinary research communications, 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

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3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

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5 · Who and what money

Authors and funding

9 authors.

Joanna Klećkowska-NawrotDepartment of Biostructure and Animal Physiology, Division of Animal Anatomy, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, Kożuchowska 1, Wrocław, 51-631, Poland.
Aleksandra Kroczak-ZdańkowskaDepartment of Genetics, Faculty of Biology and Animal Science, Wrocław University of Environmental and Life Sciences, Kożuchowska 7, Wrocław, 51-631, Poland.
Adam UrantówkaDepartment of Genetics, Faculty of Biology and Animal Science, Wrocław University of Environmental and Life Sciences, Kożuchowska 7, Wrocław, 51-631, Poland.
Grzegorz ZaniewiczDepartment of Vertebrate Ecology and Zoology, Faculty of Biology, University of Gdańsk, Wita Stwosza 59, Gdańsk, 80-308, Poland.
Shaw BadenhorstEvolutionary Studies Institute, University of the Witwatersrand, 1 Jan Smuts Ave, Braamfontein, Johannesburg, 2000, South Africa.
Aleksander ChrószczDepartment of Biostructure and Animal Physiology, Division of Animal Anatomy, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, Kożuchowska 1, Wrocław, 51-631, Poland.
Krzysztof StegmannRZGW, C. K. Norwida 34, Wrocław, 50-950, Poland.
Karolina BarszczDepartment of Morphological Sciences, Institute of Veterinary Medicine, Warsaw University of Life Sciences, Nowoursynowska 159, Warsaw, 02-787, Poland.
Dominik PoradowskiDepartment of Biostructure and Animal Physiology, Division of Animal Anatomy, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, Kożuchowska 1, Wrocław, 51-631, Poland. dominik.poradowski@upwr.edu.pl.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

The Harderian and lacrimal glands are the main orbital glands of the avian lacrimal apparatus and contribute to the tear film, nictitating membrane function, and local protection of the ocular surface. Although the ocular adnexa have been well described in domestic birds, the morphology and function of these organs remain poorly characterized in free-living species. This study aimed to characterize the morphology and histochemistry of these glands in the Great Spotted Woodpecker. The material consisted of 18 individuals found dead in the natural environment in Poland. Gross anatomical, morphometric, histological, and histochemical analyses were performed. Both glands occupied typical orbital positions. The secretory units of the Harderian gland consisted of one predominant epithelial cell type, contrasting with the more heterogeneous epithelial organization reported in some other avian species. Both glands were compound tubuloacinar structures. The Harderian gland opened into the lower conjunctival sac, whereas the smaller lacrimal gland drained into the dorsal conjunctival sac. The Harderian gland had a more homogeneous secretory parenchyma and a well-developed excretory duct system. The overall morphology of both glands was comparable to that described in other birds. However, the histochemical secretory profile differed from that reported in several species: the Harderian gland produced mainly acidic mucosubstances, whereas the lacrimal gland showed a mixed secretory profile. The immune component of both glands had a diffuse and periductal distribution, which contrasted with the pattern described in some birds. These findings show that the Harderian and lacrimal glands are structurally and histochemically distinct and suggest complementary roles in ocular surface maintenance in this species. At the same time, the results indicate selected morphological and functional differences compared with both domestic and other free-living birds.

Indexed as

BirdsHarderian GlandLacrimal ApparatusAnimalsFemaleHistocytochemistryMalePolandAvian ophthalmologyGreat spotted woodpeckerHarderian glandHistochemical analysisLacrimal glandOcular adnexa

Identifiers

PMID42747726
PMCPMC13582243

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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.