title: Milk, caseinate and lactoferrin addition to equine semen cooling extenders.
abstract: Cooled semen has been used routinely to prolong sperm viability until artificial insemination time. However, spermatozoa are subjected to oxidative stress. The aim of the present work was to investigate the protective and antioxidant effect of the milk proteins lactoferrin (Lf) and caseinate added to equine semen cooling extenders. Semen from six stallions was cooled at 5 °C after resuspension with C1) milk- and glucose-based, C2) 0.6% caseinate, C3) C2 + Lf 200 μg ml-1, C4) C2 + Lf 500 μg ml-1and C5) C2 + Lf 1000 μg ml-1extenders, and kept at 5 °C for 24 h. Sperm motility characteristics and intact membrane rates were not different among the treatments (P > 0.05). As a result of the cooling process, the nitrite concentration increased significantly in the cooled semen (69.6 ± 78.9 μm per ×106spermatozoa) compared with the fresh semen (8.6 ± 1.9 μm per ×106spermatozoa). In contrast, the H2O2concentrations were lower in the 0.6% caseinate extender (265.9 ± 221.3 μm per ×106spermatozoa) than in the milk extender (430.9 ± 199.8 μm per ×106spermatozoa, P < 0.05), showing an antioxidative effect of the caseinate compared with the milk. However, in all groups, hydrogen peroxide concentrations were similar to the undiluted fresh semen (332.8 ± 151.3 μm per ×106spermatozoa). Caseinate showed to be as efficient as milk to protect equine-cooled spermatozoon.
authors.affiliation: Clinic and surgery department, Veterinary School, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: H S
authors.initials: HS
authors.lastname: Martins
authors.affiliation: Technology and Inspection of Products of Animal, Origin Department, Veterinary School, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: M R
authors.initials: MR
authors.lastname: Souza
authors.affiliation: Technology and Inspection of Products of Animal, Origin Department, Veterinary School, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: C F A M
authors.initials: CF
authors.lastname: Penna
authors.affiliation: Institute of Biological Sciences of the Federal University of Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: G C
authors.initials: GC
authors.lastname: da Silva
authors.affiliation: Institute of Biological Sciences of the Federal University of Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: S F
authors.initials: SF
authors.lastname: Côrtes
authors.affiliation: Veterinary Faculty, PUC Minas, Betim, Bairro Angola, Betim, MG, Brazil.
authors.forename: R
authors.initials: R
authors.lastname: Stahlberg
authors.affiliation: Clinic and surgery department, Veterinary School, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil. mlagares@ufmg.br.
authors.forename: M A
authors.initials: MA
authors.lastname: Lagares
mesh_terms: D000818:Animals; D000975:Antioxidants; D002364:Caseins; D002462:Cell Membrane / Q000378:metabolism; D003080:Cold Temperature; D006736:Horses; D006861:Hydrogen Peroxide / Q000378:metabolism; D007315:Insemination, Artificial / Q000379:methods / Q000662:veterinary; D007781:Lactoferrin; D008297:Male; D008892:Milk; D009573:Nitrites / Q000378:metabolism; D012661:Semen / Q000378:metabolism; D012662:Semen Preservation / Q000379:methods / Q000662:veterinary*; D013081:Sperm Motility; D013094:Spermatozoa / Q000502:physiology
chemical_list: D000975:Antioxidants; D002364:Caseins; D009573:Nitrites; D006861:Hydrogen Peroxide; D007781:Lactoferrin
keywords: Antioxidants; casein; milk proteins; spermatozoon; stallion