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Full-Text Articles in Animal Sciences
Individual, Temporal, And Seasonal Variation In Sperm Concentration In Tree Swallows, Michael Lombardo, Armetris Forman, Matthew Czarnowski, Patrick Thorpe
Individual, Temporal, And Seasonal Variation In Sperm Concentration In Tree Swallows, Michael Lombardo, Armetris Forman, Matthew Czarnowski, Patrick Thorpe
Michael P Lombardo
We determined sperm concentrations in Tree Swallows (Tachycineta bicolor) by manually expressing semen samples from males during prelaying, egg-laying, incubation, and nestling periods. Sperm concentrations varied by orders of magnitude (0-109 sperm mL-1) among males. Sperm concentrations were highest during the incubation period and lowest during the prelaying period. None of the samples collected during the prelaying, egg-laying, and incubation periods were devoid of sperm. In contrast, 45% of samples collected during the nestling period lacked sperm. Sperm concentrations (1) did not vary over the course of the morning during prelaying, egg-laying, and incubation periods but significantly increased during the …
Microbial Colonization Of The Cloacae Of Nestling Tree Swallows, Tamara Mills, Michael Lombardo, Patrick Thorpe
Microbial Colonization Of The Cloacae Of Nestling Tree Swallows, Tamara Mills, Michael Lombardo, Patrick Thorpe
Michael P Lombardo
Microbes have the potential to be important selective forces in many aspects of avian biology. Microbes can affect fitness as a result of either their pathogenic or beneficial effects on host health. Little is known about the chronology of microbial colonization of nestlings or the effects of microbes on fledgling condition. We set out to (1) characterize the time course of microbial colonization of the cloacae of nestling Tree Swallows (Tachycineta bicolor), (2) examine the relationship between cloacal microbes and fledgling condition, and (3) determine if nest mates had similar assemblages of cloacal microbes. We repeatedly measured nestlings and sampled …