title: Boar spermatozoa encapsulated in barium alginate membranes: a microdensitometric evaluation of some enzymatic activities during storage at 18 degrees C.
abstract: The customary dilution of boar semen for subsequent artificial insemination (AI) procedures damages the cell membrane of spermatozoa, resulting in a loss of enzymes and other cytoplasmic contents and acrosomal reactions. We encapsulated non-diluted boar semen in barium alginate membranes to optimize AI procedures and to improve the functional integrity of spermatozoal membranes during storage. The percentage of non-reacted acrosomes (NRA) and measurements of enzyme leakage (cytochrome c oxidase (COX), lactate dehydrogenase (LDH), and glucose-6-phosphate dehydrogenase (G6PDH)) were used as indices of the functional status of diluted, unencapsulated and encapsulated spermatozoa, stored for 72 h at 18 degrees C. Enzymatic activity was assessed in situ by microdensitometry, and non-reacted acrosomes were microscopically determined by staining. The percentage of acrosome integrity and the intracellular enzymatic activities during storage were different for unencapsulated and encapsulated semen. Semen dilution caused a rapid decline in enzymatic activities and concomitant acrosomal reactions. Encapsulated spermatozoa had significantly higher acrosome integrity (77% versus 55%; P < 0.01 after 72 h) and an overall higher in situ enzymatic activity. For cytochrome c oxidase and lactate dehydrogenase the greatest differences between encapsulated and unencapsulated spermatozoa were present after 72 h whereas for glucose-6-phosphate dehydrogenase significant differences were found within 24h of storage. The encapsulation process maintains a better preservation environment for boar spermatozoa and could be a promising, innovative technique to improve storage of these cells.
authors.affiliation: Department of Veterinary Science and Technology for Food Safety, University of Milan, Milan, Italy
authors.forename: Massimo
authors.initials: M
authors.lastname: Faustini
authors.forename: Maria Luisa
authors.initials: ML
authors.lastname: Torre
authors.forename: Simona
authors.initials: S
authors.lastname: Stacchezzini
authors.forename: Roberta
authors.initials: R
authors.lastname: Norberti
authors.forename: Anna Lange
authors.initials: AL
authors.lastname: Consiglio
authors.forename: Franca
authors.initials: F
authors.lastname: Porcelli
authors.forename: Ubaldo
authors.initials: U
authors.lastname: Conte
authors.forename: Eleonora
authors.initials: E
authors.lastname: Munari
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Russo
authors.forename: Daniele
authors.initials: D
authors.lastname: Vigo
mesh_terms: D020101:Acrosome Reaction; D000464:Alginates; D000818:Animals; D003720:Densitometry; D003576:Electron Transport Complex IV / Q000032:analysis; D005260:Female; D005954:Glucosephosphate Dehydrogenase / Q000032:analysis; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D007315:Insemination, Artificial / Q000379:methods / Q000662:veterinary; D007770:L-Lactate Dehydrogenase / Q000032:analysis; D008297:Male; D012662:Semen Preservation / Q000379:methods / Q000662:veterinary*; D012996:Solutions; D013048:Specimen Handling / Q000662:veterinary; D013094:Spermatozoa / Q000201:enzymology*; D013696:Temperature; D013997:Time Factors
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D012996:Solutions; D020723:Glucuronic Acid; D007770:L-Lactate Dehydrogenase; D005954:Glucosephosphate Dehydrogenase; D003576:Electron Transport Complex IV