Macroscopic anatomy of the reproductive tract of the reproductively quiescent female emu (Dromaius novaehollandiae)

Three reproductively quiescent female emus (Dromaius novaehollandiae) were embalmed with 10% formalin solution. The reproductive tract was dissected and described. The reproductive tract consists of an ovary and oviduct situated on the left side of the abdominal cavity. The left ovary is dark brown to black in colour with follicles covering the ventral surface. The ovary is located medial to the spleen and closely associated with the ventral surface of the cranial and middle lobes of the left kidney. The oviduct is a relatively straight tube that extends from the level of the cranial extent of the left ilium to the caudal border of the left pubic bone. The oviduct is grossly divided into the infundibulum, magnum, isthmus, uterus and vagina using variations in the mucosal fold pattern.     

An immunohistochemical study of ovarian innervation in the emu (Dromaius novaehollandiae)

The present study investigated the distribution of nerves in the ovary of the emu. The neuronal markers, protein gene product 9.5, neurofilament protein and neuron specific enolase demonstrated the constituents of the extrinsic and intrinsic ovarian neural systems. The extrinsic neural system was composed of ganglia in the ovarian stalk, as well as nerve bundles, which were distributed throughout the ovary. Isolated neuronal cell bodies, in the medulla and cortex, formed the intrinsic neural system. An interesting finding of the study was the presence of nerve bundles, circumscribed by lymphocytes, in the ovarian stalk. The findings of the study indicate that the distribution of nerve fibres and neuronal cell bodies in the emu ovary is similar, but not identical to that of the domestic fowl and ostrich.     

In vitro initiation of the acrosome reaction in the emu (Dromaius novaehollandiae)

1. An assessment of the efficiency of the acrosome reaction (AR) provides an important predictor of the fertilizing potential of semen and for diagnosis of the causes of infertility. A standardized protocol was therefore developed for initiation of the acrosome reaction in emu spermatozoa in vitro, and the role of CaCl₂ or perivitelline membrane (PVM) proteins in determining the outcome of the reaction was investigated.

2. The acrosome reaction (assessed by FITC-PNA) was successfully induced in live spermatozoa by incubation for 2 min in NaCl-TES medium supplemented with 5 mM CaCl₂. The maximum response was 32% live acrosome-reacted spermatozoa (LAR) achieved after 10 min incubation.

3. Compared to the outcome with 5 mM CaCl₂ or PVM protein alone, the response was significantly better with a combination of PVM protein and CaCl₂.

4. A significant variation in the percentage of LAR spermatozoa among individual males was observed. No treatment affected the percentage of dead acrosome-reacted spermatozoa.

5. The results emphasize the important role played by both PVM proteins and Ca²⁺ in the in vitro initiation of the acrosome reaction.     

An immunohistochemical study of the distribution of intermediate filaments in the ovary of the emu (Dromaius novaehollandiae)

The immunohistochemical localization of the intermediate filaments desmin, vimentin and smooth muscle actin (SMA) in the ovary of the emu was described in the present study. The cortical region of the ovary contained developing and atretic primordial, pre-vitellogenic and vitellogenic follicles. Vimentin immunostaining was demonstrated in the granulosa cell layer of primordial, pre-vitellogenic and vitellogenic developing and atretic follicles. An interesting finding of the present study was the localization of SMA in fibroblasts located in the theca externa of late vitellogenic follicles. The presence of SMA in these fibroblasts suggests that they possess characteristics of smooth muscle cells.     

Seasonal and daily changes in the behaviour of the adult emu (Dromaius novaehollandiae) under farm conditions

1. The aim of this study was to present selected elements of emu behaviour in three different seasons (the non-breeding season, the pre-breeding season and the breeding season) and in the morning and afternoon. The study focused on feed, water and sand intake; plumage care; resting; agonistic behaviour and other activities, mostly standing still, aimless walking or observing the surroundings.

2. The troop consisted of 11 emus (5 females and 6 males) aged 12 years, kept in a free-range system. Observations were carried out during a period of 3 weeks in each season, during which 60-min observation sessions took place on 3 randomly chosen days.

3. A significant effect was found of each season on the behaviour patterns related to feeding, sand intake, plumage care, resting and agonistic behaviour.

4. Time of day affected the behaviour associated with the collection of food and water, foraging, pecking and ingesting sand and plumage preening.

5. Most of the time, regardless of season and time of day, the emus were standing still, walking aimlessly or observing the surrounding area.     

Identification of the major proteins of the organic matrix of emu (Dromaius novaehollandiae) and rhea (Rhea americana) eggshell calcified layer

1. The eggshell is a composite consisting of 95% calcite and an organic matrix. 2. While many proteins of the chicken eggshell matrix have already been identified, little is known about the matrix of other birds. 3. Isolation of the emu and rhea eggshell matrix and analysis of its major constituents showed that the predominant components were C-type lectin-like proteins related to those of ostrich, chicken and goose. 4. Serum albumin, vitelline membrane outer layer protein I (VMO-I) and the turpentine-induced acute phase serum protein 18-B were identified as minor components of the emu shell matrix. Both eggshell matrices also contained a novel proline- and alanine-rich protein. 5. Like ostrich, and unlike chicken and goose, both emu and rhea eggshell matrix contained two different C-type lectin-like proteins as major components, indicating that the occurrence of two proteins of this family may be widespread among ratites.     

Isolation of avian influenza virus (H10N7) from an emu (Dromaius novaehollandiae) with conjunctivitis and respiratory disease

Avian influenza virus was isolated from the conjunctiva of a male emu chick. Clinical observations included ocular discharge, dyspnea, and mild respiratory signs. Lesions included conjunctivitis, tracheitis, bronchopneumonia, and airsacculitis. Escherichia coli was isolated from the conjunctiva and the sinus, and Staphylococcus sp. was isolated from the conjunctiva. Influenza A viral nucleoprotein was detected immunohistochemically in epithelial cells of the bronchi, lung parenchyma and tracheal mucosa, and mononuclear inflammatory cells within the exudate of the bronchial lumen; conjunctiva, air sacs, kidney, intestine, and liver were negative for the viral nucleoprotein. The isolated influenza virus was typed as H10N7 and was determined to be nonpathogenic for chickens.     

Fasciola hepatica infection in farmed emus (Dromaius novaehollandiae)

Objective To describe two cases of infection with Fasciola hepatica i n young farmed emus, subacute and chronic fasci-olosis and a response to treatment of the flock with albenda-zole.
Procedure Gross lesions were found at necropsy and hepatic lesions in microscopic examination. The parasite recovered from one emu was identified by its morphological characteristics and an egg count reduction test was carried out after treatment of the flock with albendazole.
Results Hepatic lesions resembling subacute and chronic fasciolosis of ruminants were identified. An adult fluke was recovered from the liver of one of the birds and was identified as F hepatica . The eggs of the fluke were irregular in shape and size. No fluke eggs were identifiable in faeces of live emus 10 days after treatment of the flock with albendazole at a dose of 10 mg/kg.
Conclusions This is the first reported case of infection with F hepatica i n farmed emus and the first report of the occurrence of Fasciola infection is the class Aves. The irregular shape and size of the eggs may be attributable to infection of an aberrant host. Treatment with albendazole eliminated eggs from the faeces of the flock.     

Reproductive parameters in free-ranging female black rhinoceroses (Diceros bicornis) in Zimbabwe

Samples and data were collected from twenty-eight female black rhinoceroses (Diceros bicornis) during translocation efforts carried out by the Department of National Parks and Wildlife Management in Zimbabwe. Biological data were collected, cytological examination of vaginal smears was performed, and serum concentrations of follicle stimulating hormone, luteinizing hormone, progesterone, oestriol, and 17-beta-oestradiol were determined by radio-immuno-assay. Prolactin levels were determined for 3 pregnant animals, 1 of which was sampled before and after parturition. Vaginal cytology was not found to be helpful for indicating the oestrous cycle stage for the black rhinoceros, but progesterone and 17-beta-oestradiol levels were found to be useful indicators of pregnancy and possibly of oestrous cycle stage as well.     

The electrocardiogram of anesthetized captive adult emus (Dromaius novaehollandiae)

ObjectiveTo characterize the electrocardiogram (ECG) of anesthetized adult emus (Dromaius novaehollandiae).AnimalsTen clinically healthy adult emus anesthetised for routine physical examination and an electrocardiogram, for both monitoring and investigation into any evidence of cardiac disease.MethodsThe ECGs for each emu were obtained in right lateral recumbency, using a modified electrode placement that replicated the standard bipolar leads used in small mammals. Lead II was used for waveform analysis.ResultsMedian P wave amplitude was 0.55 mV (range: 0.2–0.92 mV) and P wave duration was 0.06 s (0.04–0.09 s). S wave amplitude measured 1.42 mV (0.92–2.12 mV), T wave amplitude 0.67 mV (0.16–0.83 mV) and QRS duration was 0.07 s (0.07–0.12 s). Ninety percent of the QRS complexes were of rS type.ConclusionOur study provides electrocardiographic baseline data for anesthetized adult emus.     

Carcase characteristics of emus (Dromaius novaehollandiae).

1. Six emus (Dromaius novaehollandiae) were slaughtered at 13 months of age in order to determine carcase, by-product and muscle yields. 2. Emus had a lower percentage of hot carcase weight (52%) and total fat (28%) to body weight but a higher lean meat to carcase weight (69%) than ostriches or rheas. 3. The amount of trimming of connective tissue from muscles of the lower leg (Gastrocnemius, Fibularis longus) has an influence (P<0.05) on the yields from these muscles.