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Frontiers in veterinary science2026; 13; 1867201; doi: 10.3389/fvets.2026.1867201

Ultrasonographic fetal sex determination in large domestic animals: a comparative, mechanistic, and field-oriented synthesis.

Abstract: Ultrasonographic fetal sex determination is commonly used in livestock production to aid genetic selection, reproductive planning, and economic optimization. Despite consistently high diagnostic accuracies under controlled conditions, its use in field settings is variable and frequently unpredictable. This disparity is due to the combined effects of embryological development, species-specific anatomy, fetal positioning, operator expertise, and technical limitations. Unassigned: This review aims to provide a comparative and integrative synthesis of ultrasonographic fetal sex determination across major domestic species, bridging the gap between experimental performance and field applicability. Unassigned: A comprehensive analysis was conducted, combining published literature with extensive field experience with cattle, camels, horses, and buffaloes. The review is organized around three key dimensions: (i) biological timing of sexual differentiation, (ii) diagnostic visibility of ultrasonographic landmarks, and (iii) practical feasibility in field conditions. Unassigned: Across species, the genital tubercle is the primary diagnostic landmark during early gestation; however, its visibility and diagnostic reliability vary depending on the species' developmental dynamics and imaging accessibility. One important finding is the distinction between diagnostic accuracy and diagnostic feasibility, with the latter emerging as the primary limitation in field conditions. According to comparative analysis, cattle provide the most consistent environment for early diagnosis, horses provide the broadest diagnostic window, camels present a narrow but precise window, and buffaloes are relatively under-characterized. Unassigned: Ultrasonographic fetal sex determination is a highly accurate but context-dependent tool, with success determined more by feasibility than diagnostic capability. The integration of emerging technologies, such as Doppler ultrasonography, three-dimensional imaging, and artificial intelligence, has the potential to improve consistency and reduce operator dependency. This review creates a unified framework that connects embryology, imaging, and field application, offering practical advice and defining priorities for future research in livestock reproduction.
Copyright © 2026 Ali, Derar and Alharbi.
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Publication Date: 2026-06-17 PubMed ID: 42389687PubMed Central: PMC13318662DOI: 10.3389/fvets.2026.1867201Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

Overview

  • This research article reviews the use of ultrasonographic techniques to determine fetal sex in large domestic animals, highlighting the differences between high accuracy in controlled environments and variable success in practical field conditions.
  • It compares the biological, technical, and practical aspects of this diagnostic method across multiple livestock species and suggests ways to improve reliability and usability in real-world settings.

Background and Purpose

  • Ultrasonography is widely applied in livestock production to identify the sex of fetuses, which supports genetic selection, reproductive planning, and economic decision-making.
  • Despite excellent accuracy demonstrated in laboratory or experimental scenarios, real-world applications often face challenges resulting in inconsistent outcomes.
  • The article aims to synthesize existing knowledge, combining academic literature with practical field experience to understand why variability occurs and how to bridge the gap between laboratory success and field reliability.

Methodological Approach

  • The review covers four major domestic species: cattle, camels, horses, and buffaloes, comparing the biology and ultrasonographic identification methods for fetal sex determination.
  • It is structured around three main factors:
    • Biological timing of sexual differentiation — when critical anatomical structures develop that indicate sex.
    • Diagnostic visibility of ultrasonographic landmarks — the fetal anatomical features that can be visualized and used to identify sex.
    • Practical feasibility in the field — how factors like fetal positioning, operator skill, and equipment affect real-world success.

Key Findings

  • The genital tubercle, an embryological structure, serves as the key landmark for sex determination in early gestation.
  • Visibility and reliability of this structure depend heavily on species-specific developmental timelines and anatomical factors affecting imaging access.
  • A critical insight is the distinction between:
    • Diagnostic accuracy: the theoretical or controlled-condition correctness of the determination, which is generally high.
    • Diagnostic feasibility: the practical ability to achieve accurate results under field conditions, often limited by external factors.
  • Species comparisons reveal:
    • Cattle: Offer the most consistent and reliable environment for early fetal sex determination due to clearer imaging windows and anatomy.
    • Horses: Provide a wider time frame (diagnostic window) to perform accurate sexing, offering greater flexibility.
    • Camels: Present a narrowly defined but very precise window for diagnosis, making timing critical.
    • Buffaloes: Are less well-characterized, indicating a need for further targeted study to improve understanding and methodologies.

Practical Challenges and Limitations

  • Field application of ultrasonographic fetal sexing is limited mainly by issues related to:
    • Fetal position inside the uterus, which can hinder clear visualization of landmarks.
    • Operator skill and experience, influencing the ability to correctly interpret images.
    • Technical factors like ultrasound machine settings and probe type.
  • These factors create a gap between what is possible in research settings versus everyday farm or ranch environments.

Future Directions and Innovations

  • The review highlights emerging technologies that could enhance diagnostic consistency and reduce operator dependency:
    • Doppler ultrasonography — to better visualize blood flow and improve anatomical resolution.
    • Three-dimensional ultrasound imaging — to provide more comprehensive views of fetal structures.
    • Artificial intelligence and machine learning — to assist in image interpretation and decision-making.
  • Integrating these technologies may help increase the practical feasibility of fetal sexing and narrow the gap with controlled-condition accuracy.
  • The article proposes a unified framework linking embryological development, imaging techniques, and field conditions to guide practical application and future research.

Conclusion

  • Ultrasonographic fetal sex determination in large domestic animals is a highly accurate diagnostic tool when conditions are ideal but currently experiences variable success in the field.
  • Success depends more on practical feasibility factors than on the fundamental diagnostic ability of ultrasonography.
  • Focused improvements in technology, training, and species-specific protocols can enhance the reliability and economics of livestock production involving sex determination.

Cite This Article

APA
Ali A, Derar DR, Alharbi YM. (2026). Ultrasonographic fetal sex determination in large domestic animals: a comparative, mechanistic, and field-oriented synthesis. Front Vet Sci, 13, 1867201. https://doi.org/10.3389/fvets.2026.1867201

Publication

Frontiers in veterinary science
ISSN: 2297-1769
NlmUniqueID: 101666658
Country: Switzerland
Language: English
Volume: 13
Pages: 1867201
PII: 1867201

Researcher Affiliations

Ali, Ahmed
  • Department of Clinical Sciences, College of Veterinary Medicine, Qassim University, Buraydah, Saudi Arabia.
Derar, Derar R
  • Department of Clinical Sciences, College of Veterinary Medicine, Qassim University, Buraydah, Saudi Arabia.
Alharbi, Yousef M
  • Department of Medical Biosciences, College of Veterinary Medicine, Qassim University, Buraydah, Saudi Arabia.

Conflict of Interest Statement

The author(s) declared that this work was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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