title: Addition of IGF-I to storage-cooled boar semen and its effect on sperm quality.
abstract: OBJECTIVE
  To evaluate in vitro IGF-I treatment during warming of storage-cooled boar semen and its effect on seminal quality parameters and metabolism in spermatic cells.
  
  
  METHODS
  Semen samples (n=7) warmed after stored at 15°C for 24 or 72h were divided into four equal parts. Different IGF-I concentrations (0, 50, 100 and 150ng/mL) were added to the semen samples. The samples were incubated at 37°C, and assessments were made after 0 and 120min of incubation.
  
  
  RESULTS
  For semen samples that were stored for 24h, the addition of IGF-I had no effect (p>0.05) on the total motility and intensity of movements by spermatic cells, osmotic resistance, live:dead cell ratio or total spermatic abnormalities. However, incubation with 150ng/mL IGF-I did decrease glutathione peroxidase activity (p<0.05) and reduce lipid peroxidation after 120min of incubation. For semen samples stored for 72h and incubated with IGF-I for 120min, there was a linear relationship between the IGF-I concentration and the live:dead ratio (p<0.05). There was a quadratic relationship between the IGF-I concentration and both the osmotic resistance (peak results at IGF-I=62.4ng/mL) and glutathione peroxidase activity (peak results at IGF-I=77.8ng/mL). There was no effect on lipid peroxidation (p>0.05) after 120min of incubation. Addition of IGF-I also decreased fructose utilization by spermatic cells regardless of semen storage time (p<0.05).
  
  
  CONCLUSIONS
  This study suggests that IGF-I may be beneficial to semen stored for longer periods of time. Adding 150ng/mL IGF-I improved the quality of semen stored for 24h, and adding 78ng/mL IGF-I improved the quality of semen stored for 72h.
authors.affiliation: Department of Veterinary Medicine, University of Lavras, Minas Gerais, Brazil.
authors.forename: D M
authors.initials: DM
authors.lastname: Silva
authors.forename: M G
authors.initials: MG
authors.lastname: Zangeronimo
authors.forename: L D S
authors.initials: LD
authors.lastname: Murgas
authors.forename: L G P
authors.initials: LG
authors.lastname: Rocha
authors.forename: B R
authors.initials: BR
authors.lastname: Chaves
authors.forename: B A
authors.initials: BA
authors.lastname: Pereira
authors.forename: E C P
authors.initials: EC
authors.lastname: Cunha
mesh_terms: D000818:Animals; D015925:Cryopreservation / Q000662:veterinary*; D005979:Glutathione Peroxidase / Q000378:metabolism; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D009995:Osmosis; D012661:Semen / Q000737:chemistry* / Q000187:drug effects*; D012662:Semen Preservation / Q000662:veterinary*; D013076:Sperm Count; D013081:Sperm Motility / Q000187:drug effects*; D013094:Spermatozoa / Q000187:drug effects*; D013552:Swine; D013696:Temperature
chemical_list: D007334:Insulin-Like Growth Factor I; D005979:Glutathione Peroxidase