Does multiple paternity influence offspring disease resistance?

Area of Science:

• Evolutionary biology
• Immunology
• Animal behavior

Background:

• Polyandry, mating with multiple males, is hypothesized to increase offspring genetic diversity.
• This diversity may reduce offspring susceptibility to infectious diseases.
• The role of polyandry in disease resistance is not well understood in mammals.

Purpose of the Study:

• To test if polyandry enhances offspring resistance to Salmonella Typhimurium infection in house mice.
• To investigate sex-specific differences in infection resistance and health consequences.

Main Methods:

• Experimental infection of offspring from single- and multiple-sired house mouse litters with Salmonella Typhimurium.
• Measurement of pathogen loads to assess infection resistance.
• Comparison of infection prevalence, resistance, and weight loss between litters and sexes.

Main Results:

• No significant difference in Salmonella infection prevalence or resistance was found between single- and multiple-sired litters.
• Significant genetic variation in Salmonella resistance was observed among families.
• Male mice showed higher resistance to Salmonella infection than females, with greater weight loss in females.

Conclusions:

• The study did not support the hypothesis that polyandry confers increased Salmonella resistance in house mouse offspring.
• Evidence for sex-dependent resistance to Salmonella infection in house mice was found, with males being more resistant.
• Female mice experienced more severe health consequences from infection, indicated by greater weight loss.