Paternal levels of DNA damage in spermatozoa and maternal parity influence offspring mortality in an endangered ungulate

Abstract

Understanding which factors influence offspring mortality rates is a major challenge since it influences population dynamics and may constrain the chances of recovery among endangered species. Most studies have focused on the effects of maternal and environmental factors, but little is known about paternal factors. Among most polygynous mammals, males only contribute the haploid genome to their offspring, but the possibility that sperm DNA integrity may influence offspring survival has not been explored. We examined several maternal, paternal and individual factors that may influence offspring survival in an endangered species (Gazella cuvieri). Levels of sperm DNA damage had the largest impact upon offspring mortality rates, followed by maternal parity. In addition, there was a significant interaction between these two variables, so that offspring born to primiparous mothers were more likely to die if their father had high levels of sperm DNA damage, but this was not the case among multiparous mothers. Thus, multiparous mothers seem to protect their offspring from the deleterious effects of sperm DNA damage. Since levels of sperm DNA damage seem to be higher among endangered species, more attention should be paid to the impact of this largely ignored factor among the viability of endangered species.

No inbreeding effects on body size in two captive endangered gazelles

“…However, results found by Ruiz-López et al (2010) in another trait, offspring survival, in the same species and populations are congruent with ours. Although these authors only used the inbreeding coefficient (F i ) as a measure of inbreeding, neither the parent nor the offspring inbreeding coefficients had any effect on offspring mortality.…”

Effects of inbreeding and parental incubation on captive breeding success in Hawaiian crows

“…her capability to repair damaged sperm DNA; Ruiz-Lopez et al, 2010), may provide males the chance to reproduce successfully and produce viable offspring despite being inbred. For example, in captive endangered gazelles semen quality showed clear signs of inbreeding depression (Roldan et al, 1998), but under optimal conditions males with high levels of damaged sperm still sired offspring (Ruiz-Lopez et al, 2010). On the other hand, inbred 'alala females may lay lower quality eggs that benefit from certain management practices (such as shell repairs or artificial incubation) and thus still survive.…”

“…The beneficial captive environment that provides exclusive sexual access to a female partner over a long period of time, as well as the female's qualities (such as e.g. her capability to repair damaged sperm DNA; Ruiz-Lopez et al, 2010), may provide males the chance to reproduce successfully and produce viable offspring despite being inbred. For example, in captive endangered gazelles semen quality showed clear signs of inbreeding depression (Roldan et al, 1998), but under optimal conditions males with high levels of damaged sperm still sired offspring (Ruiz-Lopez et al, 2010).…”

X–Y Interactions Underlie Sperm Head Abnormality in Hybrid Male House Mice

“…We speculate that such incompatibilities may be responsible for the reduced litter size seen in the N 3 generation (Table 1), possibly mediated by phenotypes not measured in this study. For example, excess DNA fragmentation in sperm is a phenotype strongly associated with zygotic, embryonic, and postnatal mortality in mammals (Cho et al 2003;Ruiz-López et al 2010;Robinson et al 2012).…”