Turkey Sperm Mobility Influences Paternity in the Context of Competitive Fertilization1

Abstract

We have devised a novel means of investigating competitive fertilization in turkeys, using microsatellite genotyping to identify male parentage. Our results demonstrate that sperm mobility is a mechanism responsible in part for paternity efficiency in turkeys. Sperm mobility is composed of several parameters in which sperm motility is a component. Differences between ejaculates in the number of sperm penetrating into a dense, insert, nontoxic solution were measured and used to classify males into high, average, or low sperm mobility phenotypes. Microsatellite genotyping was used to determine parentage of poults after equal numbers of sperm from 10 males (either high or average phenotype, n ‫؍‬ 5, mixed with low phenotype, n ‫؍‬ 5) were inseminated simultaneously. In a separate study, the numbers of sperm hydrolyzing the perivitelline layer of eggs were compared between hens inseminated with sperm from high-, average-, or low-phenotype males. Overall, heterospermic inseminations resulted in consistently fewer offspring produced by low-mobility phenotype males. This correlated with physiological data in which semen from the low-mobility males had reduced numbers of sperm at the fertilization site as determined by sperm hole counts in the perivitelline layer of eggs. This is the first illustration of a measurable sperm trait predictive of paternity success in a competitive fertilization trial in turkeys, a species that is predominately reproduced by artificial insemination of multiplesire pools.

Sperm morphology, adenosine triphosphate (ATP) concentration and swimming velocity: unexpected relationships in a passerine bird

“…In birds, for example, sperm must be motile to rapidly traverse the hostile environment of the vagina to gain access to sperm storage sites [4]. Energetically costly traits, such as high swimming velocity and longevity, are therefore likely to be crucial for success [5]. …”

Sperm Mobility: Phenotype in Roosters (Gallus domesticus) Determined by Mitochondrial Function1

“…Consequently, this quantitative trait [1] is highly predictive of male fertility in both noncompetitive [2] and competitive [3,4] contexts. Sperm mobility phenotype is determined by measuring the absorbance of an Accudenz solution following sperm penetration from an overlaid sperm suspension [1].…”

Behavioral Paternity Predicts Genetic Paternity in Satin Bowerbirds (Ptilonorhynchus Violaceus), a Species With a Non-Resource-Based Mating System

“…Adults and offspring were genotyped at 10 dinucleotide microsatellite loci identified in previous studies of wild or domestic turkeys (Donoghue et al 1999, Reed et al 2000, Mock et al 2002 Table 1). An 11 th locus (tum 17) was discarded from further analyses when Bonferroni-corrected linkage disequilibrium tests conducted using GENEPOP (Raymond and Rousset 1995) revealed its apparent linkage with two other loci (tum 23 and mnt 1).…”