Combined adenovirus and rotavirus enteritis with Escherichia coli septicemia in an emu chick (Dromaius novaehollandiae).
A 2-week-old emu chick (Dromaius novaehollandiae) of approximately 200 g body weight was presented for necropsy with a history of weakness, diarrhea, pallor of the head, and acute death. Hemorrhagic enteritis with mild hepatomegaly was noted on gross examination. Microscopic examination revealed necrohemorrhagic enteritis with intralesional intranuclear basophilic viral inclusion bodies in intestinal epithelial cells;…
Read MoreChanges in pattern of heat loss at high ambient temperature caused by water deprivation in a large flightless bird, the emu.
When exposed to high ambient temperatures, birds defend body temperature by increasing evaporative water loss, via either respiratory or cutaneous water loss. Water deprivation can lead to changes in thermal responses and lower levels of water use for thermoregulation. We have studied the effect of 2-3 wk of water deprivation on the physiological responses of…
Read MoreFatty Acid Analysis of Emu Oil
Emu oil has recently received attention for its possible therapeutic and cosmetic benefits. The oil of the emu has been used for medicinal purposes by the Aborigines of Australia for many years and is currently being used in the cosmetic industry for its protective and softening effects of the skin. The exact mechanism by which…
Read MoreEndocrine and testicular changes in a short-day seasonally breeding bird, the emu (Dromaius novaehollandiae), in southwestern Australia.
Seasonal changes in testicular morphology and blood plasma concentrations of LH, testosterone, and prolactin are described for captive male emus in southwestern Australia. Testicular mass and testicular testosterone did not differ between the non-breeding (spring-summer) and the breeding (autumn-winter) seasons. Nevertheless, the testes obtained in the breeding season (May and August) were nearly two fold…
Read MoreA neuroendocrine model for prolactin as the key mediator of seasonal breeding in birds under long- and short-day photoperiods.
Seasonal breeding is associated with sequential increases in plasma luteinizing hormone (LH) and prolactin in the short-day breeding emu, and in long-day breeding birds that terminate breeding by the development of reproductive photorefractoriness. A model of the avian neuroendocrine photoperiodic reproductive response is proposed, incorporating a role for prolactin, to account for neuroendocrine mechanisms controlling…
Read MoreEmbryonic heart rate measurements during artificial incubation of emu eggs.
Daily changes in embryonic heart rate (HR) of emu were determined non-invasively at 36 degrees C by acoustocardiography (ACG) during the last 30% of artificial incubation (predicted incubation time is 50 d). The pattern of daily changes in mean HR of hatched embryos decreased from about 175 bpm to about 140 bpm towards the end…
Read MoreEfferent axons in the avian auditory nerve.
The sensory hair cells of the inner ear receive both afferent and efferent innervation. The efferent supply to the auditory organ has evolved in birds and mammals into a separate complex system, with several types of neurons of largely unknown function. In this study, the efferent axons in four different species of birds (chicken, starling,…
Read MoreDMRT1 in a ratite bird: evidence for a role in sex determination and discovery of a putative regulatory element.
Unlike mammals, birds have a ZZ male/ZW female sex-determining system. In most birds, the Z is large and gene rich, whereas the W is small and heterochromatic, but the ancient group of ratite birds are characterized by sex chromosomes that are virtually homomorphic. Any gene differentially present on the ratite Z and W is therefore…
Read MoreDistribution of spermatozoa in the outer perivitelline layer from above the germinal disc of emu and ostrich eggs
To whom correspondence should be addressed. email: [email protected] Abstract In the present study, we determined the distribution of spermatozoa in the perivitelline layer above the germinal disc (GD) of emu and ostrich eggs that had been laid at random intervals after mating. Eggs were opened, the perivitelline layer overlying the GD region was collected and…
Read MoreDistribution and characterization of microsatellites in the emu (Dromaius novaehollandiae) genome.
This study generates data concerning the genome of a flightless species of bird, the emu. We examined and ultimately rejected the following hypotheses: Microsatellites are randomly distributed throughout the emu genome. The relative order of abundance of dinucleotides will be constant across genomes. Interspersion distances for a given dinucleotide will be equal across vertebrate genomes.…
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