Male Infanticide in Captive Plains Zebra
Journal of Animal Behavior, 2000
Jan Pluhacek and Ludek Bartos
The department of Zoology and science faculty at Charles University planed this experiment with the following hypothesis."Introducing a new zebra male into a herd of breeding females should increase foal Mortality in comparison with herds in which the sire of the foals is still present " (Pluhacek and Bartos, 2000). The younger the foal the higher the infanticide rate. "Male Infanticide is the killing of newborns or young juveniles by an adult male"(Pluhacek and Bartos, 2000).The encouragement for this experiment came for data recorded from five herds in two different zoological gardens in the Czech Republic. Some of the data that was obtained during this experiment included, nine records of infanticide in plains zebras and three cases of abortion that was probably induced by force.
Fifty percent of breeding mares conceive while still lactating.Most mares are providing nutrients for both foal and fetus."When a new stallion is introduced he benefits more from initiating abortion than killing foals" (pluhacek and Bartos, 2000).
The methods for this experiment are as followed.Five breeding herds of plains zebras pertaining to four subspecies.The herd sizes ranged between 3 to 5 breeding mares between the ages of 2 and 20 years old.For each foal a series of information was collected, data on date of birth, date of death, mother and father, identity, and the date of introduction of the unrelated stallion.
Any foals that were injured by the new stallion and needed medical treatment by a veterinarian and had to be separated from the herd were recorded as dead in the analysis.
The results were as expected, the plains zebras in captive did in deed try and kill new born foals from different stallions."During the duration of the experiment nine attacks resulting in heavy inju…