title: Identification of a sperm cell attribute responsible for subfertility of roosters homozygous for the rose comb allele.
abstract: Fertility, sperm metabolism, sperm filling of oviductal sperm storage tubules (SST), and sperm motility were compared in subfertile roosters homozygous for the rose comb allele (R/R) and fertile controls (r/r or R/r males). As expected, fertility of R/R males was less than that of controls (p < 0.0001). The metabolic rate of spermatozoa from R/R males was also lower than that of controls (p < 0.05). Likewise, filling of SST in vivo was lower (p < 0.0001) for spermatozoa from R/R males than for control spermatozoa. However, in vitro filling of SST was not different between genotypes (p > 0.05). Motility of spermatozoa from R/R males was less than that of controls (p < 0.001) as determined by an objective spectrophotometric assay. Previous researchers have concluded that subfertility associated with homozygosity for the rose comb allele is attributable to a sperm-specific phenomenon. However, the cellular mechanism(s) responsible for the subfertile status were not defined. In contrast to previous researchers, we have demonstrated that subfertility of R/R males is explicable in terms of reduced sperm transport through the hen's vagina; reduced sperm motility appears to be the major contributing factor.
authors.affiliation: Department of Animal Sciences, Oregon State University, Corvallis 97331, USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: McLean
authors.forename: D P
authors.initials: DP
authors.lastname: Froman
mesh_terms: D000483:Alleles; D000818:Animals; D002645:Chickens; D003129:Comb and Wattles; D005260:Female; D006720:Homozygote; D007248:Infertility, Male / Q000235:genetics / Q000662:veterinary*; D008297:Male; D010057:Oviducts; D011201:Poultry Diseases / Q000235:genetics*; D013081:Sperm Motility; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000378:metabolism / Q000502:physiology*