title: A comparative study of the effects of Escherichia coli and Clostridium perfringens upon boar semen preserved in liquid storage.
abstract: The present study compares the sperm quality of boar seminal doses artificially inoculated with Escherichia coli and Clostridium perfringens, and maintained in liquid storage at 15°C for a 9-day period. Seminal doses from 10 sexually mature Piétrain boars were diluted in a Beltsville Thawing Solution (BTS)-based extender and infected either with E. coli or C. perfringens, with bacterial loads ranging from 101to 107cfumL-1. During storage, the changes in sperm quality were determined by assessing pH, sperm viability, sperm motiliy, sperm morphology, sperm agglutination degree, and sperm-bacteria interaction. The infection of seminal doses led to an alkalinization of the medium, which was of higher extend in doses infected with C. perfringens. The effect of contamination on sperm viability and motility relied on bacterial type and load. Therefore, while E. coli was more harmful than C. perfringens in bacterial loads ranging from 101to 106cfumL-1, the detrimental impact of C. perfringens was more apparent than that of E. coli at a bacterial load of 107cfumL-1. Despite sperm morphology not being affected by either bacterial type or load, sperm agglutination and sperm-bacteria interaction were characteristic of doses infected with E. coli, and increased concomintantly with bacterial load and along storage period. In conclusion, the effects of infection by E. coli on sperm quality were dependent of both bacterial load and storage period, whereas the effects of C. perfringens were mainly dependent on the bacterial load, with a threshold at 107cfumL-1from which the sperm quality of seminal doses was greatly impaired.
authors.affiliation: Biotechnology of Animal and Human Reproduction (TechnoSperm), Department of Biology, Institute of Food and Agricultural Technology, University of Girona, E-17071 Girona, Spain. Electronic address: elisabeth.pinart@udg.edu.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Pinart
authors.affiliation: Biotechnology of Animal and Human Reproduction (TechnoSperm), Department of Biology, Institute of Food and Agricultural Technology, University of Girona, E-17071 Girona, Spain.
authors.forename: Esther
authors.initials: E
authors.lastname: Domènech
authors.affiliation: Biotechnology of Animal and Human Reproduction (TechnoSperm), Department of Biology, Institute of Food and Agricultural Technology, University of Girona, E-17071 Girona, Spain.
authors.forename: Eva
authors.initials: E
authors.lastname: Bussalleu
authors.affiliation: Biotechnology of Animal and Human Reproduction (TechnoSperm), Department of Biology, Institute of Food and Agricultural Technology, University of Girona, E-17071 Girona, Spain.
authors.forename: Marc
authors.initials: M
authors.lastname: Yeste
authors.affiliation: Biotechnology of Animal and Human Reproduction (TechnoSperm), Department of Biology, Institute of Food and Agricultural Technology, University of Girona, E-17071 Girona, Spain.
authors.forename: Sergi
authors.initials: S
authors.lastname: Bonet
mesh_terms: D000818:Animals; D058491:Bacterial Load; D002470:Cell Survival; D003016:Clostridium perfringens / Q000502:physiology*; D004926:Escherichia coli / Q000502:physiology*; D008297:Male; D012034:Refrigeration / Q000662:veterinary; D055101:Semen Analysis / Q000662:veterinary; D012662:Semen Preservation / Q000009:adverse effects / Q000379:methods / Q000662:veterinary; D013081:Sperm Motility; D013094:Spermatozoa / Q000166:cytology / Q000382:microbiology* / Q000502:physiology; D013552:Swine
keywords: Bacterial contamination; Boar semen; Clostridium perfringens; Escherichia coli; Sperm quality