title: Fertility of bull semen packaged in .25- and .5-milliliter french straws.
abstract: The fertility of bull semen packaged in .25- and .5-mL french straws was compared. One ejaculate from each of five Holstein bulls was split, extended to 10 x 10(6) spermatozoa/inseminate dose in whole homogenized milk, packaged in .25- and .5-mL french straws, frozen in liquid nitrogen (LN) vapor, and stored in LN. Semen was thawed at 37 degrees C for 30 s. Synchronized heifers (n = 1,360) were inseminated (during a 12-mo period) with semen packaged in either a .25- or .5-mL french straw. Blood was collected on the day of insemination and the serum was assayed for progesterone. Heifers with blood progesterone levels of > 1 ng/mL were eliminated from the data. Blood was collected at 30 to 45 d after insemination and the serum was assayed for the presence of bovine pregnancy-specific protein B (bPSPB) by RIA to determine pregnancy. Conception was 63.6 and 62.0% (P = .55) for semen packaged in the .25- and .5-mL french straws, respectively. There was neither a bull x packaging unit interaction (P = .49) nor a day of insemination x packaging unit interaction (P = .87). Conception among bulls ranged from 57.1 to 68.0% (P = .19). No evidence was found that meteorological factors influenced conception. Under the conditions of this experiment, semen packaged in the .25- and .5-mL french straw had similar fertility.
authors.affiliation: Department of Animal Sciences, Washington State University, Pullman 99164-6332, USA.
authors.forename: M S
authors.initials: MS
authors.lastname: Johnson
authors.forename: P L
authors.initials: PL
authors.lastname: Senger
authors.forename: C H
authors.initials: CH
authors.lastname: Allen
authors.forename: D D
authors.initials: DD
authors.lastname: Hancock
authors.forename: B M
authors.initials: BM
authors.lastname: Alexander
authors.forename: R G
authors.initials: RG
authors.lastname: Sasser
mesh_terms: D000818:Animals; D002417:Cattle / Q000097:blood / Q000502:physiology*; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary*; D005260:Female; D005298:Fertility / Q000502:physiology*; D005306:Fertilization / Q000502:physiology; D007315:Insemination, Artificial / Q000379:methods / Q000592:standards / Q000662:veterinary; D008297:Male; D011374:Progesterone / Q000097:blood; D011863:Radioimmunoassay / Q000662:veterinary; D012661:Semen / Q000502:physiology*; D012662:Semen Preservation / Q000379:methods / Q000662:veterinary*; D013094:Spermatozoa / Q000502:physiology
chemical_list: D011374:Progesterone