Comparison of culturing Mycoplasma gallisepticum from fresh eggs and 18-day-old embryos

Twenty-four 70-week-old and sixteen 27-week-old white leghorn hens were challenged with R strain Mycoplasma gallisepticum (MG) by injection into the caudal thoracic air sac and infraorbital sinus. Eggs were collected daily and cultured within 7 days or incubated for 18 days. Vitelline membranes of eggs were cultured directly; in 18-day-old embryos, cultures were taken from the yolk sac, air sacs, and oral cavity. Culture of vitelline membrane of eggs within 2 days was compared with culture of eggs stored 10 days post oviposition. The first MG-positive egg was laid 2 days postinfection (PI). Hens continued to lay positive eggs to the end of the experiments. There was no significant difference in MG recovery between eggs cultured within 2 days and those cultured 10 days post oviposition. MG was isolated at a significantly higher rate from eggs than from 18-day-old embryos. MG was isolated at a higher rate from the yolk sac of 18-day-old embryos than from the air sacs or oral cavity of the same embryos.     

Atypical parasitic migration and necrotizing sacral myelitis due to Serratospiculoides amaculata in a prairie falcon (Falco mexicanus)

An adult, wild-caught, female prairie falcon (Falco mexicanus) was presented with the chief complaint of anorexia. Radiographic findings included increased densities within the air sacs, and coelomic endoscopy revealed numerous slender worms within the air sacs and on the serosal surfaces of the ovary, oviduct, liver, proventriculus, and ventriculus. The bird seemed to improve for a short period of time with antiparasitic therapy (ivermectin and fenbendazole) and supportive care. Twenty-one days after initial presentation, the bird became recumbent with increasing pelvic limb neurologic deficits and was euthanized. On histopathologic examination, mature nematodes and larvated eggs identified as Serratospiculoides amaculata were found within the subdural space of the distal thoracolumbar and synsacral spinal cord and within the coelomic cavity. This case suggests that S. amaculata can cause clinically significant lesions in its falconiform host with potentially fatal results.     

Gross morphological features of the air sacs of the hooded crow (Corvus cornix)

Air sacs are considered to be one of the controlling factors of bird behaviour and habits in addition to their roles in ventilation, regulating body temperature, swimming and flight. As a scavenger and an omnivorous flight bird, air sacs of the hooded crow were the focus of this study. Eight healthy, adult hooded crows were used to examine the morphological characteristics of the air sacs, which were examined grossly and with latex and cast preparations. In general, the morphological overview of the hooded crow air sacs is similar to other avian species. We observed nine air sacs; four paired sacs (cervical, cranial thoracic, caudal thoracic and abdominal air sacs) and one unpaired sac; the clavicular air sac. The cervical air sac communicated to the lung through the medioventral bronchus and had three diverticula; intermuscular, subscapular and subcutaneous. The clavicular air sac communicated with lung through the medioventral bronchus and had subscapular, axillary, humeral, subpectoral and sternal diverticula. The cranial and caudal thoracic air sacs were communicated with lung through the lateroventral bronchi and the both sacs did not have any diverticula. The abdominal air sacs were posterior to the caudal thoracic air sacs. The left abdominal sac was the largest air sac. The right and left abdominal sacs gave off branches to diverticula that pneumatized synsacrum. The abdominal air sacs gave off femoral diverticula behind the hip joint as well as perirenal diverticula.     

Acute airsacculitis in turkeys inoculated with Pasteurella multocida

Thirty female turkeys, inoculated into the caudal thoracic air sacs with Pasteurella multocida were examined from 0 to 6 hours post-inoculation (PI). The air sac reacted rapidly and intensely with exudation of heterophils. Circulating leukocyte and thrombocyte numbers remained normal except for an absolute lymphopenia by 6 hours PI. P. multocida was initially isolated from blood at 3 hours PI. Total cell counts increased markedly in air sac lavage fluids by 1.5 hours PI and continued to increase until 6 hours PI. Heterophils predominated in lavage fluids (greater than 94%), with macrophages comprising the remaining cells. Microscopically occasional heterophils were present within air sac blood vessels and perivascularly by 0.5 hour PI. They became more numerous by 1.5 and 3 hours PI when transepithelial migration into the air sac lumen was seen. By 6 hours PI, there was diffuse, severe swelling of air sac epithelium and mesothelium, and bacteria were located in air sac interstitium. Ultrastructurally, endothelial and air sac epithelial cells were swollen and vacuolated Interdigitating processes of air sac epithelial cells were separated. These results indicate that air sacs can be the portal of entry for P. multocida into the systemic circulation, probably via damaged air sac epithelium.     

Exercise-induced pulmonary haemorrhage in the horse: results of a detailed clinical, post mortem and imaging study. II. Gross lung pathology

Gross post mortem examinations were performed on the lungs of 26 Thoroughbred horses of known exercise-induced pulmonary haemorrhage (EIPH) status. The most consistent finding was a variable degree of bilaterally symmetrical, dark discolouration of the dorsocaudal regions of the caudal lung lobes. In more severely affected lungs, the stained areas extended cranially along the dorsal surfaces of the lungs, and in some cases affected approximately one third of the lung surface. Discoloured areas of lung were denser than normal, collapsed less readily, often contained trapped air and were slow to inflate. The subpleural bronchial arteries were more prominent in the discoloured regions. Pleural adhesions were noted in two horses but were not related to the discoloured lung regions. It was concluded that the discoloured lesions have a complex pathogenesis and were related directly to previous bouts of EIPH. Associated with them were signs indicating probable partial small airway obstruction, decreased tissue compliance and direct involvement of the bronchial arterial circulation.     

Bandaging, endoscopy, and surgery in the emergency avian patient.

This article is divided into three parts and describes procedures used in avian medicine after initial stabilization. The first part includes the application of bandages and splints for fractures. The second part describes the use of endoscopy to examine the choana, oral cavity, trachea, and, to a lesser extent, internal organs. The last part discusses equipment required and techniques used for esophagostomy tube placement, air sac cannulation, and surgery, with approaches to the coelomic cavity and a select number of surgical procedures. This article is intended to provide the emergency animal clinician with knowledge necessary to provide basic stabilization for avian patients and knowledge of procedures that can be performed by the experienced clinician.     

COMPUTED TOMOGRAPHIC ANATOMY AND CHARACTERISTICS OF RESPIRATORY ASPERGILLOSIS IN JUVENILE WHOOPING CRANES

Respiratory diseases are a leading cause of morbidity and mortality in captivity reared, endangered whooping cranes (Grus americana). Objectives of this retrospective, case series, cross‐sectional study were to describe computed tomography (CT) respiratory anatomy in a juvenile whooping crane without respiratory disease, compare CT characteristics with gross pathologic characteristics in a group of juvenile whooping cranes with respiratory aspergillosis, and test associations between the number of CT tracheal bends and bird sex and age. A total of 10 juvenile whooping cranes (one control, nine affected) were included. Seven affected cranes had CT characteristics of unilateral extrapulmonary bronchial occlusion or wall thickening, and seven cranes had luminal occlusion of the intrapulmonary primary or secondary bronchi. Air sac membrane thickening was observed in three cranes in the cranial and caudal thoracic air sacs, and air sac diverticulum opacification was observed in four cranes. Necropsy lesions consisted of severe, subacute to chronic, focally extensive granulomatous pathology of the trachea, primary bronchi, lungs, or air sacs. No false positive CT scan results were documented. Seven instances of false negative CT scan results occurred; six of these consisted of subtle, mild air sacculitis including membrane opacification or thickening, or the presence of small plaques found at necropsy. The number of CT tracheal bends was associated with bird age but not sex. Findings supported the use of CT as a diagnostic test for avian species with respiratory disease and tracheal coiling or elongated tracheae where endoscopic evaluation is impractical.     

METASTATIC GRANULOSA CELL TUMOR IN A MANGROVE SNAKE (BOIGA DENDROPHILA MELANOTA)

A 12-year-old, female mangrove snake (Boiga dendrophila melanota) was presented with a 1-month history of anorexia, lethargy, and progressive distention of the caudal coelomic cavity. Based on ultrasonographic and cytological examination, an ovarian neoplasia was considered to be the presumptive antemortem diagnosis. Histological examination confirmed the diagnosis of a granulosa cell tumor (GCT) with metastatic tumors in the coelomic fat bodies. Four months following oophorectomy and surgical removal of the distant metastasis, the snake was euthanized because of sudden onset of lethargy, cardiomegaly, and dyspnea. Postmortem examination revealed the presence of metastatic tumors in the lung, liver, and kidneys. Primary ovarian neoplasms are relatively rare in reptiles. Although GCTs have been documented in snakes, definitive diagnosis is typically determined through postmortem histopathological examination. The present case describes a suitable antemortem diagnostic approach of a malignant GCT in a mangrove snake with distant metastases.     

Acute airsacculitis in turkeys inoculated with cell-free culture filtrate of Pasteurella multocida

Twenty-six female and 26 male turkeys, inoculated into the caudal thoracic air sacs with cell-free culture filtrate of Pasteurella multocida strain R44/6, were examined from 0 to 6 hours post-inoculation and compared with 26 female and 26 male sham-inoculated control turkeys given brain-heart-infusion broth. The air sac reacted rapidly with exudation of heterophils. Microscopically, low numbers of heterophils were present within air sac blood vessels and also perivascularly by 0.5 hour after inoculation. These became more numerous by 1.5 and 3 hours post-inoculation. By 6 hours post-inoculation, there was severe swelling of air sac epithelial and mesothelial cells and thickening of the air sac by proteinaceous fluid and heterophils. Ultrastructurally, mesothelial and air sac epithelial cells were vacuolated, and interdigitating processes of epithelial cells were separated. Microscopically, in control turkeys, rare heterophils were present perivascularly at 1.5, 3, and 6 hours after inoculation. Ultrastructurally, all features were normal. In turkeys given cell-free culture filtrate, total cell counts in air sac lavage fluids increased markedly by 3 hours post-inoculation in which heterophils predominated (greater than 97%). There were only slight increases in cell counts of air sac lavages from control turkeys. The circulating blood heterophil cell count dropped transiently at 1.5 hours post-inoculation, followed by a return to normal 3 hours after inoculation, and by heterophilia by 6 hours post-inoculation in turkeys given either cell-free culture filtrate or brain-heart-infusion broth. These results indicate cell-free culture filtrate of P. multocida induces hematologic, cytologic, and morphologic changes indistinguishable from those induced by cultures of P. multocida.     

Ultrasonographic anatomy of reproductive female leopard geckos (Eublepharis macularius)

Captive leopard geckos (Eublepharis macularius) often present to the exotic clinic for gastrointestinal impactions, follicular stasis, or dystocia. To our knowledge, normal ultrasonographic anatomy of these lizards has not been described. The objectives of this prospective, anatomic, analytical study were to develop ultrasound techniques for this species and to describe the normal sonographic anatomy of the head, coelomic cavity, and tail. Eleven, healthy, female leopard geckos were included. A linear array 13–18 MHz transducer was used. Geckos were sedated and restrained in dorsal recumbency for coelomic structure examination and in ventral recumbency for head and tail examinations. Sagittal and transverse images were acquired and authors recorded qualitative and quantitative ultrasonographic characteristics of anatomic structures. The ventral surface of the lungs, liver, gallbladder, caudal vena cava, portal vein, ventral abdominal vein, aorta, ovarian follicles, fat bodies, tail, and brain were visualized in 10 of 11 individuals. In one individual, molt precluded ultrasonographic examination. The heart, kidneys, urinary bladder, spleen, and pancreas were not visualized. The digestive tract was observed in 10 individuals but was too small to be measured. Findings from the current study could be used as a reference for future studies of leopard geckos.     

Ultrasonographic appearance of the coelomic cavity organs in healthy veiled chameleons (Chamaeleo calyptratus) and panther chameleons (Furcifer pardalis)

Veiled chameleons (Chamaeleo calyptratus) and panther chameleons (Furcifer pardalis) are the most popular chameleons over the world, and consequently, two of the most frequent species presenting to veterinary practices. However, published studies on normal ultrasonographic anatomy for these lizards are currently lacking. The objectives of this prospective anatomic study were to develop an ultrasound protocol for evaluation of the coelomic cavity in these species and describe the normal ultrasonographic anatomy of the coelomic organs. Seventeen healthy veiled chameleons and 15 healthy panther chameleons were included. A linear 18 MHz transducer was used. Chameleons were sedated and restrained in right lateral recumbency by an assistant. Longitudinal and transverse images were acquired, and authors recorded qualitative and quantitative ultrasonographic characteristics of the coelomic structures. The kidneys, liver, caudal vena cava, hepatic veins, portal vein, gallbladder, wall of the stomach and intestine, gonads and, when distended, urinary bladder could be visualized during ultrasonography of the coelomic cavity in both species. The spleen, pancreas, and adrenal glands could not be identified. Findings from the current study supported the use of ultrasonography for veiled chameleons (Chamaeleo calyptratus) and panther chameleons (Furcifer pardalis) with suspected intracoelomic diseases and provided normal reference information for future studies of these chameleon species.     

Endoscopic examination of snakes by access through an air sac

Sixteen boa constrictors (Boa constrictor), three royal pythons (Python regius) and 15 Burmese pythons (Python molurus bivittatus) were examined endoscopically by access through the air sac. The snakes were immobilised in a ventral position using a half-open anaesthetic system with assisted ventilation and a mixture of isoflurane and oxygen. The rigid endoscope was introduced percutaneously and the internal structure of the lungs and the air sac, and the shape, size and external surface of the liver were visible in the cranial direction. In the smaller snakes the bifurcation and caudal part of the trachea could be viewed, provided the endoscope was positioned in a retrograde orientation. The caudal orientation of the endoscope made it possible to view the gall bladder and the size, shape and surface of the spleen. In some cases, the pancreas and the surface of the stomach and colon could be monitored. Endoscopy through the air sac also made it possible to check the major veins in the coelom. The snakes were monitored for at least 30 days after the intervention and no changes in their respiratory function or general health were observed.     

Ultrasonographic appearance of the coelomic cavity in healthy green iguanas

OBJECTIVE: To describe the ultrasonographic appearance of the coelomic cavity in healthy green iguanas. DESIGN: Cross-sectional study. ANIMALS: 26 healthy green iguanas (20 males and 6 females). PROCEDURES: For coelomic ultrasonography, animals were physically restrained in dorsal recumbency by an assistant; chemical restraint was not used. Qualitative and quantitative observations were recorded. RESULTS: Structures that could be visualized in all animals included the heart and cardiac chambers; liver; caudal vena cava; hepatic veins; portal vein; gallbladder; pyloric portion of the stomach; and, when distended, urinary bladder. Visualization of the kidneys was poor. The spleen could be identified in 17 animals, and the gonads could be identified in 22, but were most easily identified in males evaluated during November (ie, during the breeding season); no females were evaluated during the breeding season. Physiologic enlargement of the testes yielded an acoustic window for the spleen by displacing overlying intestine. Anechoic, free coelomic fluid was identified in 3 animals. Measurements of overall cardiac size, ventricular wall thickness, gallbladder size, thickness of the pyloric portion of the stomach, and splenic size were obtained. Only ventricular wall thickness was significantly correlated with body weight. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that ultrasonography allowed examination of most coelomic structures in green iguanas. The procedure was easily performed and was well tolerated in conscious animals.     

IMAGING DIAGNOSIS—USE OF RADIOGRAPHY AND COMPUTED TOMOGRAPHY IN THE DIAGNOSIS OF A MINERALIZED YOLK SAC IN A BROWN KIWI (APTERYX MANTELLI)

A 12‐day‐old Brown Kiwi (Apteryx mantelli) was presented with anorexia, torticollis, head‐tilt, and coelomic distension. Radiographs showed an ill‐defined, fat‐opaque, coelomic mass displacing viscera craniodorsally. Curvilinear mineral opacities were superimposed over the ventral aspect of the mass. Computed tomography demonstrated the presence of mineral within the periphery of a fat attenuating mass consistent with a retained yolk sac. A deutectomy (yolk sac excision) was performed. Histopathology of the excised tissue confirmed the diagnosis of a retained yolk sac with multifocal mineralization.     

Study of nebulization delivery of aerosolized fluorescent microspheres to the avian respiratory tract

This study investigated the delivery of an aerosol of monodisperse microspheres to the respiratory tract of birds following aerosol exposure. Adult domestic pigeons (Columbia livia domestica, n = 5 birds per timed treatment) were exposed to an aerosol of fluorescent 1.0 microm diameter carboxylate microspheres for 0.5, 1, 2, or 4 hr. During the aerosolization period, the birds were free-standing in a plexiglass treatment chamber and the aerosol was delivered using a commercial nebulizer. Immediately following aerosol exposure, the birds were euthanatized and the carcasses were intravenously infused with a modified paraformaldehyde/gluteraldehyde fixative. Evaluation of microsphere distribution was performed using a stereoscopic microscope with an epifluorescent module. The results from this study revealed that the amount of aerosolized particles delivered using a commercial nebulizer was proportional to exposure periods. Aerosol exposure periods of 0.5 hr or 1 hr did not result in a readily observable distribution of 1.0 microm fluorescent microspheres to the cranial thoracic, caudal thoracic, or abdominal air sac membranes. This was partly attributed to the relatively low concentration of the individual monodisperse microspheres in the aerosolized suspension. The 2- and 4-hr exposure periods resulted in readily observable deposition of the 1.0 mirom fluorescent microspheres in the cranial thoracic, caudal thoracic, or abdominal air sac membranes, with the 4-hr exposure period resulting in the greatest number of particles on the membrane surfaces. For each of the exposure periods, there was individual animal variation regarding the distribution and relative number of spheres deposited. This study demonstrates the widespread deposition of particles that had an aerodynamic equivalent diameter of approximately 1 microm and provides a better understanding of particle deposition efficiency within the respiratory system following aerosol exposure in birds.     

Radiography and computed tomography of the heart and lower respiratory tract in toco toucans (Ramphastos toco)

This study aimed to evaluate normal features of the heart and lower respiratory tract in toco toucans by means of radiography and helical computed tomography (CT) scanner. Fifteen healthy adult toco toucans (Ramphastos toco), 10 females and 5 males, average body mass of 650 g were studied. CT examination as well as right lateral and ventrodorsal radiographic examinations of the coelomic cavity were performed under chemical restraint. Heart, lungs, air sacs, trachea and syrinx were analysed. The mean values of heart length, heart width and thoracic cavity in radiographs were, respectively, 23.76 mm, 25.94 mm and 48.87 mm. In both X-rays and CT scans, the lung parenchyma had honeycomb-like pattern. The topographic areas of the anterior and posterior air sacs were visualized as dark and air-filled spaces in X-rays. On CT evaluation, the air sacs occupied a larger area in the coelomic cavity compared to X-ray. In the lateral radiographic view, the cervical part of the trachea was positioned more ventrally in the transition from cervical to thoracic regions showing a V-shaped appearance. In all CT planes was visible division of the trachea into the right and left main bronchi at the level of 3rd thoracic vertebra. The syrinx was difficult to visualize in X-rays, but on CT it was easily identified in axial slice. In conclusion, the normal features of toco toucan's heart and lower respiratory tract that were determined on X-rays and CT scans are useful to compare with sick toco toucans, as well as other bird species.     

TRANSCUTANEOUS ULTRASONOGRAPHY OF THE COELOMIC VISCERA OF THE OSTRICH (Struthio camelus)

Ultrasonographic examinations were performed on clinically healthy growing and adult nonbreeding female ostriches. Multiple acoustic windows and the normal ultrasonographic appearance of the coelomic viscera were described. Good images of the heart and its major vessels, proventriculus, ventriculus, intestines, liver, and kidneys could be obtained. Additionally, an anechoic structure, believed to function as an urinary bladder, could be imaged in the cloacal region. The pancreas, spleen, thyroid glands, ovary, and adrenals could not be seen in this study. General limitations were the size of the ostriches, massive leg and dorsal muscles, large sternum, the extensive air sac system, compact convoluted intestines, and varying amounts of gastrointestinal gas. Ostriches do not posses a gall bladder, and thus it could not be used as a landmark or acoustic window. The extensive air sac system and feathers did not limit the use of ultrasonography as much as anticipated. Imaging of air sacs should, however, be considered to detect pathology such as air sacculitis, which may result in consolidation. Veterinary     

Diagnostic and Surgical Arthroscopy of the Equine Shoulder Joint

An arthroscopic technique for examination and surgical treatment of conditions of the shoulder joint was evaluated in eight normal horses and two horses with osteochondrosis lesions. A single arthroscope entry point caudal to the infraspinatus tendon allowed inspection of the cranial, lateral, and caudal surfaces of the shoulder joint. With the humeral head and glenoid cavity distracted by a curved forceps, the entire cartilage surface of the shoulder could be examined. The caudomedial portion of the humeral head was seen better with a 70 degree angled arthroscope. Instruments for intra-articular manipulation were introduced through a separate skin incision 2 to 4 cm caudal to the arthroscope entry point. Two horses with osteochondrosis lesions of the shoulder were examined arthroscopically and debrided with instrument triangulation. Five normal horses and both horses with osteochondrosis lesions were euthanized immediately after the procedure and a necropsy was performed. Minor iatrogenic damage to the cartilage surfaces and joint capsule resulted from the technique. Three horses recovered from anesthesia and were killed 3, 30, or 60 days after surgery. Subcutaneous fluid that accumulated during surgery had resorbed by 3 days and lameness was evident for 12 to 24 hours. Gross examination and histopathologic findings of specimens collected at 30 and 60 days showed several small nonhealing partial-thickness cartilage defects attributed to instrument insertion. Arthroscopy is a satisfactory method to examine the joint surfaces and to evaluate and treat osteochondrosis lesions of the shoulder joint in horses.