_____________________________________________________________________________________________________ *Corresponding author: Email: juliamarisa@pancabudi.ac.id; Asian Journal of Advanced Research and Reports 8(4): 42-46, 2020; Article no.AJARR.55100 ISSN: 2582-3248 Membrane Integrity Test for Spermatozoa in Simmental Bull Liquid Semen Using the Addition of Gentamycin and Sweet Orange Essential Oil in the Extender Sukma Aditya Sitepu 1 and Julia Marisa 2* 1 Department of Animal Husbandry, Faculty of Science and Technology, Pembangunan Panca Budi University, Medan, Indonesia. 2 Department of Agrotechnology, Faculty of Science and Technology, Pembangunan Panca Budi University, Medan, Indonesia. Authors’ contributions This work was carried out in collaboration between both authors. Author SAS designed the study, performed the statistical analysis, wrote the protocol and wrote the first draft of the manuscript. Author JM managed the analyses of the study. Both authors read and approved the final manuscript. Article Information DOI: 10.9734/AJARR/2020/v8i430206 Editor(s): (1) Dr. Fagbadebo Omololu Michael, Durban University of Technology, South Africa. Reviewers: (1) Dennis Amaechi, University of Abuja, Nigeria. (2) O. Oluwole Olufunke, Obafemi Awolowo University, Nigeria. (3) Popoola Mustapha Ayodele, Nigeria. Complete Peer review History: http://www.sdiarticle4.com/review-history/55100 Received 28 December 2019 Accepted 04 March 2020 Published 12 March 2020 ABSTRACT Aims: This study aimed to determine the quality of Simmental Bull liquid semen through laboratory tests, including the percentage value of membrane integrity Spermatozoa with the addition of gentamycin and sweet orange essential oil to tris yolk extender. Methodology: The material used in this research is Simmental Cattle bull fresh semen, tris yolk extender, gentamicin, and sweet orange essential oil. Tris yolk extender was prepared with Tris (hydroxymethyl aminomethane) (3.32 g), citric acid (1.86 g), fructose (1.37 g), glycerol (6 ml), egg yolk (20 ml), aquades (100 ml). The experimental design used in the study was a nonfactorial Complete Randomized Design with five treatments and five replicates. The treatment given is the addition of sweet orange essential oil 0%, 0.25%, 0.5%, 0.75% and 1%. The parameter observed was the evaluation of membrane integrity before equilibration and after equilibration. Original Research Article