The Role and Importance of Standardization in Experiment Animals Research: Traditional Review

Abstract

Preclinical studies form the basis of many research types in different medical sciences disciplines. Experimental animals are an important part of these studies; They are living model organisms used to understand biological, physiological, and pathological mechanisms, examine system responses, and reveal their relationships. Standardization of experimental animal research refers to keeping biological and environmental factors constant that may affect experimental findings. Thus, equivalent and comparable results are obtained when similar procedures are applied in another laboratory under the same constant conditions. The primary factors affecting standardization are the sum of the intra-experimental and inter-experimental variations. Experiments are affected by these sources of variation and lead to different findings. The main purpose of standardization is to reduce variations in the experiment. Reducing variations statistically minimizes the number of animals used in studies and increases animal welfare. In addition, lowering variations prevents wasted time and money. Standardized experiments enable repeatability, interlaboratory comparability, and scientific reliability. Planning the experimental process management under the research hypothesis, minimizing the bias in the procedures, and specifying the improvement techniques applied to the research, if any, increase the quality of scientific research. With the standardization applied since the experimental design in experimental animal research, qualified research increases and contributes to scientific progress. Therefore, this review aims to emphasize the importance of controlling the environment, housing, feeding conditions, and experimental methods used in the standardization of animal experiments in the light of current paradigms, to raise awareness on this issue, to determine the effects of standardized or non-standardized experiments on animal welfare and research results reveal its effects.

Keywords

• Animal Research
• Standardization
• Laboratory Animal Science

Deney Hayvanları Araştırmalarında Standardizasyonun Yeri ve Önemi: Geleneksel Derleme

Abstract

Preklinik çalışmalar, tıp bilimlerinin farklı disiplinlerdeki birçok araştırmanın temelini oluşturmaktadır. Bu çalışmaların önemli bir bölümünde yer alan deney hayvanları; biyolojik, fizyolojik ve patolojik mekanizmaları anlamak, sistem yanıtlarını incelemek ve türler arasındaki ilişkileri ortaya çıkarmak için kullanılan canlı organizmalardır. Deney hayvanları araştırmalarında standardizasyon, deneysel bulgulara etki eden biyolojik ve çevresel faktörlerin benzer olmasını ifade eder. Böylece, benzer araştırma prosedürleri sabit koşullarda bir başka laboratuvarda uygulandığında, eşdeğer ve birbiri ile karşılaştırılabilir sonuçların alınması sağlanır. Standardizasyonu etkileyen öncelikli faktörler, deney içi ve deneyler arası varyasyonların bütünü olarak değerlendirilmektedir. Bu varyasyon kaynakları ile deneyler etkilenir ve farklı bulguların ortaya çıkmasına sebep olur. Standardizasyonun asıl amacı, deneydeki varyasyonları azaltmaktır. Varyasyonların azaltılması istatistiksel olarak çalışmalarda kullanılan hayvan sayısının azaltılmasını ve hayvan refahının artmasını sağlar. Ayrıca, varyasyonların azaltılması zaman ve para israfını da önler. Standardize deneyler; tekrar edilebilirliğe, laboratuvarlar arası karşılaştırılabilirliğe ve bilimsel güvenilirliğe olanak sağlar. Araştırmanın hipotezine uygun deneysel süreç yönetiminin planlanması, prosedürlerdeki yanlılığın en aza indirilmesi, eğer varsa araştırmaya uygulanan iyileştirme tekniklerinin belirtilmesi bilimsel araştırmaların kalitesini artırır. Deney hayvanları araştırmalarında deneysel tasarımdan itibaren uygulanan standardizasyon ile nitelikli araştırmalar artar, bilimsel ilerlemeye katkı sağlar. Dolayısıyla bu derlemenin amacı, güncel paradigmalar ışığında hayvan deneylerinin standartlaştırılmasında, kullanılan deney hayvanlarının çevre, barınma, beslenme koşullarının ve uygulanan deneysel yöntemlerin sabit tutulması ile kontrol altına alınmasının önemini vurgulamak, bu konuda farkındalık yaratmak ve standardize olan ya da olmayan deneylerin hayvan refahı ve araştırma sonuçları üzerindeki etkilerini ortaya koymaktır.

Keywords

• Hayvan Araştırmaları
• Standardizasyon
• Laboratuvar Hayvanları Bilimi

References

1. 1. National Research Council (US) Committee. Guide for the Care and Use of Laboratory Animals. 8. Baskı. Washington (DC): National Academies Press (US); 2011. PMID: 21595115.
2. 2. Laboratory vs. Experimental Animals – CroLASA [Internet]. 2022 [Erişim tarihi: 3 Ekim 2022]. https://www.crolasa.com/en/laboratorijske-zivotinje/
3. 3. Sert NP du, Ahluwalia A, Alam S, Avey MT, Baker M, Browne WJ, et al. Reporting animal research: Explanation and elaboration for the ARRIVE guidelines 2.0. PLOS Biol. Public Library of Science. 2020;18(7): e3000411.
4. 4. Russell WMS, Burch RL. The Principles of Humane Experimental Technique. 1. Baskı. İngiltere: Methuen Publishing Ltd.; 1959.
5. 5. Poyraz Ö. Laboratuvar Hayvanları Bilimi. 1. Baskı. Ankara: Kardelen Ofset.; 2000. p. 21–40.
6. 6. Enriquez J, Mims BMD, Trasti S, Furr KL, Grisham MB. Genomic, microbial and environmental standardization in animal experimentation limiting immunological discovery. BMC Immunol. 2020; 21:50. PMCID: PMC7464063.
7. 7. Van Zutphen LFM, Baumans V, Beynen AC, eds. İde T, çeviri editörü. Laboratuvar Hayvanları Biliminin Temel İlkeleri. 1. Baskı. Ankara: Özkan Matbaacılık Ltd. ŞTİ.; 2003.
8. 8. Richter SH, Garner JP, Auer C, Kunert J, Würbel H. Systematic variation improves reproducibility of animal experiments. Nat Methods. 2010;7(3):167–168.

9. 9. Van der Staay FJ, Arndt SS, Nordquist RE. Evaluation of animal models of neurobehavioral disorders. Behav Brain Funct. 2009;5(1):11.
10. 10. Kafkafi N, Agassi J, Chesler EJ, Crabbe JC, Crusio WE, Eilam D, et al. Reproducibility and replicability of rodent phenotyping in preclinical studies. Neurosci Biobehav Rev. 2018; 87:218–232. PMCID: PMC6071910.
11. 11. Paylor R. Questioning standardization in science. Nat Methods. 2009; 6(4):253–254.
12. 12. Voelkl B, Altman NS, Forsman A, Forstmeier W, Gurevitch J, Jaric I, et al. Reproducibility of animal research in light of biological variation. Nat Rev Neurosci. 2020; 21(7):384–393.
13. 13. Omary MB, Cohen DE, El-Omar EM, Jalan R, Low MJ, Nathanson MH, et al. Not all mice are the same: Standardization of animal research data presentation. Hepatology. 2016;63(6):1752–1754.
14. 14. Fontoura-Andrade JL, Amorim RFB de, Sousa JB de. Improving reproducibility and external validity. The role of standardization and data reporting of laboratory rat husbandry and housing. Acta Cir Bras. 2017; 32(3):251–262. PMID: 28403350.
15. 15. Richter SH, Garner JP, Würbel H. Environmental standardization: cure or cause of poor reproducibility in animal experiments? Nat Methods. 2009; 6(4):257–261.
16. 16. Von Kortzfleisch VT, Karp NA, Palme R, Kaiser S, Sachser N, Richter SH. Improving reproducibility in animal research by splitting the study population into several ‘mini-experiments.’ Sci Rep. 2020;10(1):1-16.
17. 17. Goodman SN, Fanelli D, Ioannidis JPA. What does research reproducibility mean? Sci Transl Med. American Association for the Advancement of Science; 2016; 8(341):341ps12-341ps12.
18. 18. Kenett RS, Shmueli G. Clarifying the terminology that describes scientific reproducibility. Nat Methods. 2015; 12(8):699–699.
19. 19. Wahlsten D, Metten P, Phillips TJ, Boehm II SL, Burkhart-Kasch S, Dorow J, et al. Different data from different labs: Lessons from studies of gene–environment interaction. J Neurobiol. 2003; 54(1):283–311.
20. 20. Jonker RM, Guenther A, Engqvist L, Schmoll T. Does systematic variation improve the reproducibility of animal experiments?. Nat Methods. 2013; 10(5):373–373.
21. 21. Festing MFW. Refinement and reduction through the control of variation. Altern Lab Anim ATLA. 2004; 32 Suppl 1A:259–263. PMID: 23577470.
22. 22. Directive 2010/63/EU Of The European Parliament and of the Council of 22 September 2010 On the Protection of Animals used for Scientific Purposes. Official Journal of European Union. EU (2010).
23. 23. Deneysel ve diğer bilimsel amaçlar için kullanılan hayvanların refah ve korunmasına dair yönetmelik. Resmî Gazete, Sayı: 28141 (13 Aralık 2011).
24. 24. Burke DA, Magnuson DS, Nunn CD, Fentress KG, Wilson ML, Shum-Siu AH, et al. Use of Environmentally Enriched Housing for Rats with Spinal Cord Injury: The Need for Standardization. J Am Assoc Lab Anim Sci. 2007;46(2):34–41.
25. 25. Design Requirements Manual (DRM): Biomedical and animal research facilities design policies and guidelines. The National Institutes of Health. 2016 [Erişim tarihi: 5 Ekim 2022]. https://orf.od.nih.gov/TechnicalResources/Pages/DesignRequirementsManual2016.aspx
26. 26. Barnard DE, Lewis SM, Teter BB, Thigpen JE. Open- and Closed-Formula Laboratory Animal Diets and Their Importance to Research. J Am Assoc Lab Anim Sci JAALAS. 2009; 48(6):709–713. PMCID: PMC2786923
27. 27. European Convention for the Protection of Vertebrate Animals Used for Experimental and other Scientific Purposes. Council of Europe, ETS No. 123. (2006).
28. 28. Genç B. Laboratuvar Hayvanı Diyetleri ve Hayvan Besleme Bilimindeki Yeri. Lalahan Hayvancılık Araşt Enstitüsü Derg. 2017;57(2):105–111.
29. 29. Griesemer JR, Gerson EM. Of Mice and Men and Low Unit Cost. Stud Hist Philos Sci Part C Stud Hist Philos Biol Biomed Sci. Elsevier; 2006;37(2):363–372.
30. 30. Lewejohann L, Zipser B, Sachser N. “Personality” in laboratory mice used for biomedical research: A way of understanding variability?. Dev Psychobiol. 2011;53(6):624–630.
31. 31. Valdar W, Solberg LC, Gauguier D, Cookson WO, Rawlins JNP, Mott R, et al. Genetic and Environmental Effects on Complex Traits in Mice. Genetics. 2006;174(2):959–984.
32. 32. Kilkenny C, Browne W, Cuthill IC, Emerson M, Altman DG. Animal research: Reporting in vivo experiments: The ARRIVE guidelines. Br J Pharmacol. 2010;160(7):1577–1579.
33. 33. Kilkenny C, Browne WJ, Cuthill IC, Emerson M, Altman DG. Improving Bioscience Research Reporting: The ARRIVE Guidelines for Reporting Animal Research. Journal of Pharmacology and Pharmacotherapeutics. 2010; 1(2):94-99. PMCID: PMC2893951.
34. 34. Van der Worp HB, Howells DW, Sena ES, Porritt MJ, Rewell S, O’Collins V, et al. Can Animal Models of Disease Reliably Inform Human Studies?. PLOS Med. 2010;7(3): e1000245.
35. 35. Landis SC, Amara SG, Asadullah K, Austin CP, Blumenstein R, Bradley EW, et al. A call for transparent reporting to optimize the predictive value of preclinical research. Nature. 2012; 490(7419):187–191. PMCID: PMC3511845.
36. 36. Pritt S, Duffee N. Training Strategies for Animal Care Technicians and Veterinary Technical Staff. ILAR J. 2007;48(2):109–119.
37. 37. Begley CG, Ioannidis JPA. Reproducibility in Science. Circ Res. 2015; 116(1):116–126.
38. 38. Kennedy BW, Froeschl K. Education and Training. Weichbrod RH, Thompson GAH, Norton JN, editörler. Management of Animal Care and Use Programs in Research, Education, and Testing. 2. Baskı. Amerika, Boca Raton (FL): CRC Press/Taylor & Francis; 2018. p.221-265. PMID: 29787224.
39. 39. Duffee N, Nevalainen T, Hau J. Education and training. In Handbook of Laboratory Animal Science. 4. Baskı. Amerika, Boca Raton (FL): CRC Press/Taylor & Francis; 2021. p. 937-948.
40. 40. Collins FS, Tabak LA. Policy: NIH plans to enhance reproducibility. Nature. 2014; 505(7485):612–613.