Anatomia Histologia Embryologia最新文献

{"title":"Chamber-Specific Morphometry and Quantitative Cardiac Histology in the Broad-Snouted Caiman (Caiman latirostris)","authors":"Maria Eduarda Natal Nascimento,&nbsp;Gabriela Nogueira Maggio,&nbsp;Maysa Barbosa de Almeida,&nbsp;Caio Rafael Siqueira Vasconcelos,&nbsp;Vinícius José da Silva Cardoso de Brito,&nbsp;Arianne Pontes Oriá,&nbsp;Fernanda Gosuen Gonçalves Dias,&nbsp;Marcela Aldrovani Rodrigues","doi":"10.1111/ahe.70183","DOIUrl":"10.1111/ahe.70183","url":null,"abstract":"<p>Quantitative cardiac morphology remains poorly documented in crocodilians. Hearts from four commercially reared male <i>Caiman latirostris</i> were examined by gross morphometry, histology, stereology, reticulin staining and Masson's trichrome. Relative heart mass averaged 0.125% of body mass. The left ventricular wall was numerically thicker than the right. Cardiomyocyte volume density and cross-sectional area varied among chambers, whereas collagen-positive area was greater in the right ventricle. Pulmonary arterial walls were markedly thinner than the systemic aortae, and the left pulmonary arterial wall was thicker than the right. These findings extend quantitative cardiac reference data for this species.</p>","PeriodicalId":49290,"journal":{"name":"Anatomia Histologia Embryologia","volume":"55 6","pages":""},"PeriodicalIF":0.9,"publicationDate":"2026-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/ahe.70183","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149197684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evolutionary Inferences Based on Thoracic Limb Muscles of South American Coati (Nasua nasua): Brachium and Craniolateral Antebrachium","authors":"Juan Fernando Vélez García,&nbsp;Roseâmely Angélica de Carvalho Barros,&nbsp;Maria Angelica Miglino","doi":"10.1111/ahe.70182","DOIUrl":"10.1111/ahe.70182","url":null,"abstract":"<p>The South American coati (<i>Nasua nasua</i>) is a mammal of the order Carnivora and family Procyonidae, characterized by scansorial locomotion. Accordingly, several anatomical and functional studies examined its thoracic limbs. Nevertheless, the anatomical descriptions and terminology differ among those studies, and none considered the evolutionary derivations of the brachium and antebrachium muscles based on topology, innervation and anatomical variants. Therefore, the present study aimed to infer the muscle derivations and reconstruct muscle maps of the brachial and craniolateral antebrachial muscles in <i>N. nasua</i> based on the evidence from direct gross dissections and comparisons with literature in embryology and myology of representative mammals from monotremes to procyonids. The caudomedial group will be addressed in a separate manuscript. Seventeen thoracic limbs from eight formaldehyde-fixed specimens and one fresh specimen of <i>N. nasua</i> were dissected. As main results that differed from the available literature, the cranial part of the tensor fasciae antebrachii muscle of non-<i>Nasua</i> procyonids was not lost in <i>N. nasua</i> but fused to the caudal part. The <i>anconeus medialis</i> muscle was not a head of the <i>triceps brachii</i> muscle and may have derived from the caudomedial antebrachial musculature. The <i>caput accessorium</i> of the <i>triceps brachii</i> muscle may have derived mainly from its <i>caput laterale</i>. The <i>extensor carpi radialis</i> muscle was undivided proximally and only separated into two bellies (<i>longus</i> and <i>brevis</i>) from the middle third of the antebrachium. In conclusion, the brachium and craniolateral antebrachium muscles of <i>N. nasua</i> had several differences from those described previously, and most evolutionary derivations could be inferred.</p>","PeriodicalId":49290,"journal":{"name":"Anatomia Histologia Embryologia","volume":"55 6","pages":""},"PeriodicalIF":0.9,"publicationDate":"2026-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/ahe.70182","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149197653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Serial Cross-Sectional Mapping of Bone Marrow Microenvironment Remodelling During Fracture Repair Using Multiparametric MRI and Histopathology","authors":"Rui Zhou,&nbsp;Guochen Li,&nbsp;Yinglin Zhou,&nbsp;Caihong Yao,&nbsp;Liuyi Deng,&nbsp;Xianchun Zeng","doi":"10.1111/ahe.70181","DOIUrl":"10.1111/ahe.70181","url":null,"abstract":"<div>\u0000 \u0000 <p>Restoring bone marrow microenvironment (BMM) homeostasis is critical for fracture healing, yet non-invasively tracking physiological events like apoptosis, angiogenesis and matrix remodelling remains challenging. This study evaluated multiparametric 7.0T MRI (T2 mapping and proton density-weighted imaging [PDWI]) for in vivo tracking of BMM spatiotemporal remodelling during natural and pharmacologically accelerated bone repair. Utilizing a rat tibial drill-hole injury model (<i>N</i> = 36), we compared a natural healing control with a Huoxue Qiangji Decoction (HQD) intervention group. Serial high-resolution sagittal MRIs were acquired at days 7, 14 and 21, with signal intensity ratios (SIR) normalized to ipsilateral intact marrow using ITK-SNAP. Distance correlation (dCor) analysis explored non-linear dependencies between MRI metrics and histological features (c-cas3, Masson's trichrome and day-14 CD31/Ki67 expression). Results showed distinct MRI signal trajectories, with earlier homeostatic stabilization in the accelerated healing group. Spatiotemporal mapping revealed closely mirrored non-linear dependencies between MRI and histology. Specifically, T2 mapping SIR mirrored early-stage apoptosis (dCor = 0.527) and mid-term cellular proliferation (Ki67, dCor = 0.732). Concurrently, PDWI reflected dynamic trends of mid-term angiogenesis (CD31, dCor = 0.637) and late-stage collagen deposition (dCor = 0.480). In conclusion, normalized multiparametric MRI provides complementary macroscopic insights into BMM histological progression, highlighting its potential as an objective, non-invasive translational tool for monitoring musculoskeletal healing.</p>\u0000 </div>","PeriodicalId":49290,"journal":{"name":"Anatomia Histologia Embryologia","volume":"55 6","pages":""},"PeriodicalIF":0.9,"publicationDate":"2026-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149185816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Hydrogen Peroxide and Potassium Hydroxide Softening Treatments on the Histological Preparation and Morphology of Sunda Porcupine (Hystrix javanica) Quills","authors":"Maharani Kartika Ramadhan,&nbsp;Andhika Yudha Prawira,&nbsp;Bramantyo Wikantyoso,&nbsp;Ni Luh Putu Rischa Phadmacanty,&nbsp;Rizki Fitrawan Yuneldi,&nbsp;Srihadi Agungpriyono,&nbsp;Berry Juliandi","doi":"10.1111/ahe.70184","DOIUrl":"10.1111/ahe.70184","url":null,"abstract":"<div>\u0000 \u0000 <p>The Sunda porcupine (<i>Hystrix javanica</i>) possesses keratin-based quills with exceptional rigidity, necessitating softening porcupine treatments for histological and ultrastructural analyses. This study evaluated the effectiveness of 30% hydrogen peroxide (H₂O₂) alone and in combination with 20% potassium hydroxide (KOH) on true, flat and rattle quills. Quills from 12 captive Sunda porcupines were subjected to treatments of varying durations and examined using histology and scanning electron microscopy (SEM). Treatment with 30% H₂O₂ produced moderate softening after 3 days in flat and rattle quills, whereas true quills required 7 days of immersion but remained less effectively softened. In contrast, the combined treatment of 30% H₂O₂ and 20% KOH achieved effective softening within 25–30 min, resulting in softer texture, increased quill diameter and improved sectioning quality. Histological analyses revealed structural differences among quill types, while SEM showed that 30% H₂O₂ alone produced surface cracking while retaining discernible interfibrillar boundaries. In contrast, the combined treatment with 30% H₂O₂ and 20% KOH resulted in a more irregular macrofibril surface, indistinct interfibrillar boundaries and interfibrillar fusion. These findings indicate that the H₂O₂ + KOH protocol provides a more efficient and rapid method than H₂O₂ alone, although optimization is necessary to minimise artefacts and preserve structural integrity. Overall, this combination offers a practical approach for preparing porcupine quills for microscopic evaluation, while future studies should investigate milder alternatives and explore the biomedical potential of quill-derived keratin.</p>\u0000 </div>","PeriodicalId":49290,"journal":{"name":"Anatomia Histologia Embryologia","volume":"55 6","pages":""},"PeriodicalIF":0.9,"publicationDate":"2026-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149185767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shape-Based Classification and Anatomical Localization of Phalanges in Hamdani Sheep and Hair Goats","authors":"Hadji Chiuta Salimu,&nbsp;Nedzad Hadžiomerović,&nbsp;Ozan Gündemir","doi":"10.1111/ahe.70185","DOIUrl":"10.1111/ahe.70185","url":null,"abstract":"<div>\u0000 \u0000 <p>Reliable identification of isolated sheep and goat phalanges is challenging because of the close skeletal similarity between these species and the repeated arrangement of homologous digital bones across the forelimbs, hindlimbs, and medial-lateral positions. This study evaluated three-dimensional phalangeal shape for discrimination between 12-month-old male Hamdani sheep and Hair goats and for localization among the sampled anatomical positions. Proximal phalanx (P1), middle phalanx (P2), and distal phalanx (P3) from 30 male Hamdani sheep (<i>Ovis aries</i>) and 30 male Hair goats (<i>Capra hircus</i>), all 12 months of age, were analysed. Bone-specific configurations of 60, 77, and 60 surface pseudolandmarks were used for P1, P2, and P3, respectively. Three-dimensional shape provided substantially greater diagnostic information than centroid size. Shape-only species classification reached 98.3% for P1, 98.3% for P2, and 100% for P3, whereas forelimb-hindlimb classification reached 100%, 98.3%, and 96.2%, respectively. P1 provided the strongest discrimination among the four sampled compound anatomical positions, achieving 91.1% internal classification accuracy. Size-only classification accuracy ranged from 48.5% to 58.6%, compared with 98.3–100.0% for shape-only models. P2 showed the largest adjusted breed-species effect in the animal-mean analysis (partial <i>R</i>² = 0.421), whereas P3 yielded the highest internal species-classification accuracy (100.0%) and the largest descriptive sheep-goat mean-shape distance within its own phalanx-specific shape space. Importantly, P3 showed no significant interspecific centroid-size difference despite perfect shape-based species classification, demonstrating that its diagnostic signal was primarily geometric rather than size-dependent. Overall, the results revealed a phalanx-specific diagnostic pattern within the present reference sample: P3 yielded the highest observed breed-species classification accuracy, whereas P1 provided the strongest discrimination of limb region and the four sampled compound anatomical positions. These findings support discrimination within the present modern reference sample; independent validation across other breeds, both sexes, different ages, and archaeological specimens of molecularly confirmed taxon is required before routine application.</p>\u0000 </div>","PeriodicalId":49290,"journal":{"name":"Anatomia Histologia Embryologia","volume":"55 6","pages":""},"PeriodicalIF":0.9,"publicationDate":"2026-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149185782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultrastructural and Immunohistochemical Characterisation of the Pancreas in the American Bullfrog (Lithobates catesbeianus), with Special Emphasis on Telocytes","authors":"Zilong Ge,&nbsp;Honghua Chen,&nbsp;Wenjun You,&nbsp;Canying Liu,&nbsp;Yaqiong Ye,&nbsp;Hui Zhang","doi":"10.1111/ahe.70186","DOIUrl":"10.1111/ahe.70186","url":null,"abstract":"<div>\u0000 \u0000 <p>The pancreas is a crucial digestive and endocrine organ, yet the histology of the animal pancreas remains incompletely elucidated, particularly in amphibians. This study aimed to elucidate the histology of the American bullfrog (<i>Lithobates catesbeianus</i>) pancreas using histological, immunohistochemical, transmission electron microscopic methods. Histologically, the pancreas displayed typical exocrine acini and scattered endocrine islets. Two types of endocrine cells were distinguished based on their secretory granules: Type I, found diffusely among acini and containing rounded granules (0.28 ± 0.07 μm), and Type II, forming islets and containing rod-shaped granules (major axis 0.37 μm; minor axis 0.12 μm). Importantly, telocytes (TCs) were observed within the pancreatic stroma, characterised by small cell bodies and long telopodes (Tps) with podoms (0.51–2.71 μm) and podomers (0.08–0.14 μm). TCs established close contacts with acinar cells, islets, capillaries and nerve fibres. Most notably, ribosome-associated vesicles (RAV) (mean diameter: 0.27 ± 0.07 μm) were found adjacent to Tp podoms. Immunohistochemistry revealed CD34⁺, c-Kit⁺ and vimentin⁺ interstitial cells with morphological features consistent with TCs, forming a stromal network surrounding acini and islets. This study presents the first ultrastructural and immunohistochemical evidence of TCs and their associated RAV in the pancreas of <i>L. catesbeianus</i>. These findings demonstrate that TCs are structurally integrated interstitial cells in the amphibian pancreas; moreover, RAVs were observed in the vicinity of Tps.</p>\u0000 </div>","PeriodicalId":49290,"journal":{"name":"Anatomia Histologia Embryologia","volume":"55 6","pages":""},"PeriodicalIF":0.9,"publicationDate":"2026-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149185765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial, Histochemical, and Ultrastructural Analysis of Melanomacrophages in the Liver of the Red-Eared Slider (Trachemys scripta elegans)","authors":"Kengo Kasamatsu,&nbsp;Takuma Kozono,&nbsp;Ma Suzanneth G. Lola,&nbsp;Toshinori Yoshida,&nbsp;Tetsuhito Kigata","doi":"10.1111/ahe.70178","DOIUrl":"10.1111/ahe.70178","url":null,"abstract":"<div>\u0000 \u0000 <p>Melanomacrophages (MMs) are pigmented phagocytic cells observed in ectotherms. Investigating MMs is valuable for elucidating the evolutionary background of the vertebrate immune system. However, studies regarding the distribution and function of hepatic MMs remain limited. This study investigated the spatial distribution, histochemical, and ultrastructural characteristics of intracellular inclusions in hepatic MMs in red-eared sliders (<i>Trachemys scripta elegans</i>). MMs are distributed throughout the periphery of the hepatic portal system, with minimal presence elsewhere. MMs contained heterogeneous intracellular inclusions with variable staining characteristics on Masson's trichrome, periodic acid-Schiff, and Berlin blue stains. These findings provide an anatomical basis for comparative immunological investigations of MMs.</p>\u0000 </div>","PeriodicalId":49290,"journal":{"name":"Anatomia Histologia Embryologia","volume":"55 6","pages":""},"PeriodicalIF":0.9,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149118017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Respiratory Apparatus of Adult Spur-Winged Geese (Plectropterus gambensis): Gross Anatomy and Morphometrics","authors":"Mohammed K. Malah,&nbsp;Ibrahim A. Girgiri,&nbsp;Yagana B. Majama,&nbsp;Baba G. Gambo,&nbsp;Shettima Burah,&nbsp;Waziri A. Kachamai,&nbsp;Musa Zakariah","doi":"10.1111/ahe.70179","DOIUrl":"10.1111/ahe.70179","url":null,"abstract":"<div>\u0000 \u0000 <p>The present study describes the gross morphological features and morphometric characteristics of the respiratory apparatus of adult Spur-winged Geese (<i>Plectropterus gambensis</i>), a resident waterfowl species of the Sudano-Sahelian wetlands of Nigeria. Ten ethically obtained adult birds comprising five males and five females were used for this purpose. A standardized gross dissection technique was employed following euthanasia to examine the respiratory viscera. The paired slit-like openings of the nostrils were dorsolateral at the base of the upper beak. The nasal cavity was divided into two equal halves by the nasal septum and consisted of a rostral vestibular region and a broader caudal region containing the nasal conchae, each with a distinct morphological outline. The cranial larynx presented a paired dorsal arytenoid cartilage and a caudal cricoid cartilage capped by the laryngeal mound. The mean length of the trachea in males was 34.72 ± 0.87 cm comprising 138–146 tracheal rings. In females, the trachea measured 31.42 ± 0.74 cm and contained 136–142 tracheal rings. The syrinx was tracheobronchial type. The primary bronchi presented C-shaped cartilages. The paired bright red lungs were triangular shaped, spongy and displayed impressions on their surfaces from contact with adjacent structures. The extrapulmonary primary bronchi and pulmonary vessels entered the lungs through the ventral hilar region. This study establishes the first normal respiratory baseline for the spur-winged goose, filling a critical gap in avian comparative anatomy. The findings also support research on tropical wetland adaptations and provide a practical diagnostic tool for veterinarians.</p>\u0000 </div>","PeriodicalId":49290,"journal":{"name":"Anatomia Histologia Embryologia","volume":"55 6","pages":""},"PeriodicalIF":0.9,"publicationDate":"2026-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149082824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Branching Patterns, Morphometry, and Topographical Anatomy of the Aortic Arch and Subclavian Arteries in the Domestic Cat (Felis catus)","authors":"Ghasem Akbari,&nbsp;Mohammad Babaei,&nbsp;Mohammad Saleh Mansori,&nbsp;Atabak Shokrollahi","doi":"10.1111/ahe.70180","DOIUrl":"https://doi.org/10.1111/ahe.70180","url":null,"abstract":"<div>\u0000 \u0000 <p>Comprehensive knowledge of feline vascular anatomy is essential for accurate diagnostic imaging interpretation and safe thoracic cardiovascular surgery. This study aimed to characterize the branching patterns, quantitative morphometry, and precise topographical positions of the aortic arch branches and subclavian arteries in domestic cats (<i>Felis catus</i>). Twenty adult cat cadavers from Northwestern Iran were examined. Coloured latex was injected into the aortic arch, followed by fixation in 10% neutral buffered formalin and subsequent meticulous gross dissection. Topographical positions relative to thoracic skeletal landmarks and morphometric distances were recorded. Non-parametric Mann–Whitney U tests were used for statistical comparisons between identified patterns. Two branching configurations of the brachiocephalic trunk were identified: a bifurcated pattern (85%, <i>n</i> = 17) and a trifurcated pattern (15%, <i>n</i> = 3). The aortic arch was predominantly located at the fourth intercostal space (90%). For the left subclavian artery, three branching patterns were identified, with sequential origin (VT-IT-CCT-SC) being predominant (55%). The right subclavian artery exhibited three distinct arrangements, dominated by sequential (45%) and opposite [IT≡VT] origins (45%). Significant side-dependent variations were observed in the branching order and topography. Morphometric distances (BC + RS, BC-LS, and LCC-RCC) showed no statistically significant differences between bifurcated and trifurcated patterns (<i>p</i> &gt; 0.05). Feline aortic arch branches exhibit substantial topographical variation despite overall metric consistency across branching types. The observed bilateral asymmetry and internal thoracic artery positional mobility likely reflect distinct embryological origin pathways. These findings provide critical baseline anatomical data for improving the accuracy and safety of feline surgical interventions and diagnostic imaging interpretation.</p>\u0000 </div>","PeriodicalId":49290,"journal":{"name":"Anatomia Histologia Embryologia","volume":"55 6","pages":""},"PeriodicalIF":0.9,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149068302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Histology of Liver Vascular-Biliary Tracts and Associated Exocrine Pancreas in Guppies (Poecilia reticulata) at Three Post-Hatch Ages","authors":"Sisandra Sousa,&nbsp;Maria J. Rocha,&nbsp;Eduardo Rocha","doi":"10.1111/ahe.70175","DOIUrl":"10.1111/ahe.70175","url":null,"abstract":"<div>\u0000 \u0000 <p>To describe the structural development of the liver in young guppies (<i>Poecilia reticulata</i>) and complement the adult characterisation, we conducted a histological study at 7, 17, and 28 days post-birth. We used serial sections to trace the organisation of blood vessels, bile ducts, and pancreatic tissue within and around the liver. At all ages, the liver was highly cellular and composed mainly of hepatocytes. Pigmented melanomacrophage centres or aggregates were not observed, whereas rodlet cells were rare and restricted to extrahepatic connective tissue. At 7 days, we identified four distinct venous entry points. This multi-afferent pattern persisted at Days 17 and 28. Arterioles remained restricted to the outer hilar region and were not observed within the liver. The gallbladder and common hepatic duct were recognisable at Day 7. In contrast, intrahepatic bile ducts were not discernible at Day 7, were scarce at Day 17, and were more frequent, although still limited, at Day 28. Exocrine pancreatic tissue was mainly extrahepatic at Day 7; intrahepatic pancreatic acini were detected in one fish at this age and were increasingly observed at Days 17 and 28 in association with afferent venous tracts. No vascular–biliary associations comparable to those described in adult guppies were observed. These findings establish a histological baseline for normal post-hatching liver development in guppies and provide a reference for future studies in comparative anatomy and of environmentally associated changes in liver structure during early life stages.</p>\u0000 </div>","PeriodicalId":49290,"journal":{"name":"Anatomia Histologia Embryologia","volume":"55 5","pages":""},"PeriodicalIF":0.9,"publicationDate":"2026-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148907975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}