Vet World   Vol.18   September-2025  Article - 21 

Phenotype- and age-associated variations in non-specific agglutinins and complement components (C3 and C5a) in camels: Implications for transfusion compatibility and immune function

Background and Aim: Blood transfusion in camels is hindered by poorly understood blood group systems, non-specific agglutinins, and a lack of standardized cross-matching protocols. Non-specific agglutinins, primarily immunoglobulin M (IgM), can lead to cross-reactivity, while complement components C3 and C5a impact transfusion outcomes and immune responses. This study aimed to evaluate age- and phenotype-related variations in non-specific agglutinins, C3, and C5a in camels to assess implications for transfusion compatibility and innate immunity.

Materials and Methods: A total of 360 healthy male camels representing three phenotypes (black, yellow, and white) and four age groups (3–5, 5–8, 8–10, and >10 years) were sampled from slaughterhouses in Saudi Arabia. Serum agglutinin titers were determined using hemagglutination assays with heterologous red blood cells (RBCs). Heat inactivation (56°C, 30 min) and sheep RBC (SRBC) adsorption were applied to assess antibody specificity. C3 and C5a concentrations were quantified using an enzyme-linked immunosorbent assay. Statistical analyses employed analysis of variance with Tukey’s post hoc test (p<0.05).

Results: Yellow camels exhibited the highest agglutinin titers (up to 1338.4 ± 119.3 against black RBCs), with significant age-related increases. White camels showed the lowest reactivity but demonstrated marked age-related increase in C3 (3.252 ± 0.578 to 4.829 ± 0.983 μg/mL) and C5a (2.776–3.525 μg/mL). Black camels displayed moderate complement levels, peaking in older animals. Heat inactivation and SRBC adsorption substantially reduced titers across all phenotypes, confirming IgM dominance. Age-related increases in agglutinins and complement components indicated immune matura­tion or cumulative antigen exposure.

Conclusion: Phenotypic and age-related immune differences significantly affect transfusion compatibility in camels. Yellow camels’ high agglutinin activity poses greater transfusion risks, whereas white camels’ lower reactivity and higher com­plement activity suggest potential as universal donors. Age-adjusted and phenotype-matched transfusion protocols, pre-transfusion heat inactivation, and monitoring C5a in older camels could enhance transfusion safety. This is the first comprehensive study linking camel phenotype and age to complement activation (C3 and C5a), providing a framework for improved transfusion practices and future genomic research into complement-related traits.

Keywords: camel phenotypes, complement C3, complement C5a, innate immunity, non-specific agglutinins, transfusion compatibility.

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How to cite this article: Alharbi YM (2025) Phenotype- and age-associated variations in non-specific agglutinins and complement components (C3 and C5a) in camels: Implications for transfusion compatibility and immune function, Veterinary World, 18(9): 2811–2822.

Received: 23-05-2025   Accepted: 12-08-2025   Published online: 23-09-2025

Corresponding author: Yousef M. Alharbi    E-mail: yhrby@qu.edu.sa

DOI: 10.14202/vetworld.2025.2811-2822

Copyright: Alharbi, et al. This article is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.