Biomaterial Database

Cryopreservation of dog semen in a Tris extender with two different 1% soybean preparations compared with a Tris egg yolk extender. 2021

Ulrika Hermansson, and Anders Johannisson, and Eva Axnér

University Animal Hospital, Uppsala, Sweden.

Egg yolk is widely used as a cryoprotectant in dog semen extenders, but there is a risk of contamination with animal pathogens. In addition, egg yolk may vary in composition, making it difficult to standardize the extender. Lecithin is an animal protein-free alternative to egg yolk for semen cryopreservation. Recently, it was shown that 1% of soybean lecithin type II-S was better than 2% for freezing canine semen. The aim of the study was to compare two different types of soybean lecithin, with egg yolk as a control. Ejaculates from eight dogs were divided into three equal parts and diluted with a Tris-based extender, containing either 20% egg yolk, 1% soybean lecithin Type II-S or 1% soybean lecithin Type IV-S. The samples were then frozen. Sperm motility was evaluated by computer-assisted sperm analysis (CASA), acrosome integrity (FITC-PNA/PI) and sperm membrane integrity (SYBR-14/PI) post-thaw, as well as after 2 and 4 hr incubation at 37°C. Post-thaw sperm chromatin structure assay and plasma membrane integrity were evaluated by flow cytometry. Total motility, sperm plasma membrane integrity and acrosome integrity were significantly better in the egg yolk extender than in the two soybean lecithin-based extenders. Individual motility post-thaw differed more than in the fresh samples, illustrating individual differences in tolerance to the cryostress. The DNA Fragmentation Index (% DFI) was significantly lower in the Tris egg yolk (TEY) extender compared to any of the soybean-based extenders. The number of high green stained spermatozoa were significantly higher in Type IV-S compared to the control TEY extender. In conclusion, egg yolk was superior to the two lecithin-based extenders to cryopreserve canine semen.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D003451	Cryoprotective Agents	Substances that provide protection against the harmful effects of freezing temperatures.	Cryoprotective Agent,Cryoprotective Effect,Cryoprotective Effects,Agent, Cryoprotective,Agents, Cryoprotective,Effect, Cryoprotective,Effects, Cryoprotective
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D004530	Egg Yolk	Cytoplasm stored in an egg that contains nutritional reserves for the developing embryo. It is rich in polysaccharides, lipids, and proteins.	Egg Yolks,Yolk, Egg,Yolks, Egg
D005079	Excipients	Usually inert substances added to a prescription in order to provide suitable consistency to the dosage form. These include binders, matrix, base or diluent in pills, tablets, creams, salves, etc.	Excipient,Stabilizing Agent,Stabilizing Agents,Suspending Agent,Suspending Agents,Agent, Stabilizing,Agent, Suspending,Agents, Stabilizing,Agents, Suspending
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012661	Semen	The thick, yellowish-white, viscid fluid secretion of male reproductive organs discharged upon ejaculation. In addition to reproductive organ secretions, it contains SPERMATOZOA and their nutrient plasma.	Seminal Plasma,Plasma, Seminal
D012662	Semen Preservation	The process by which semen is kept viable outside of the organism from which it was derived (i.e., kept from decay by means of a chemical agent, cooling, or a fluid substitute that mimics the natural state within the organism).	Frozen Semen,Sperm Preservation,Preservation, Semen,Preservation, Sperm,Semen, Frozen
D014325	Tromethamine	An organic amine proton acceptor. It is used in the synthesis of surface-active agents and pharmaceuticals; as an emulsifying agent for cosmetic creams and lotions, mineral oil and paraffin wax emulsions, as a biological buffer, and used as an alkalizer. (From Merck, 11th ed; Martindale, The Extra Pharmacopoeia, 30th ed, p1424)	Tris Buffer,Trisamine,Trometamol,Tri(hydroxymethyl)aminomethane,Tris(hydroxymethyl)aminomethane,Tris-Magnesium(II)-Potassium Chloride Buffer,Tris-Mg(II)-KCl Buffer,Trizma