Osteosynthese van een mid-diafysaire femurfractuur met behulp van type I 'tie-in-fixator' bij een kookaburra (Dacelo novaeguineae)

In this case report, the successful management of a traumatic fracture of the femur in a kookaburra using a type I tie-in-fixator (TIF) is described. A domesticated, five-month-old kookaburra (Dacelo novaeguineae) suffered trauma due to interspecies aggression. Clinical and radiographic examination showed a closed, multiple transverse, spiral femoral fracture, located in the mid-diaphysis. Reduction of the fracture was managed using a type I TIF, combining an intra-medullar (IM) pin in combination with an external skeletal fixator. Postoperative radiographs confirmed an optimal reduction of the fracture and a correct placement of the type I TIF. Recovery was uneventful and correct positioning and normal functioning of the leg were observed immediately following surgery. One week postoperatively, the bird removed the external fixation but this did not interfere with the acquired stability and positioning of the affected leg. Two weeks after the surgery, radiographs confirmed a good healing of the fracture as callus development and bridging of the cortices were present. Based on the clinical and radiographic findings, it was decided to remove the IM pin. During a three-month follow-up period, the kookaburra showed full recovery

An atypical case of proventricular dilatation in a Red-and-green Macaw (Ara Chloropterus)

A Red-and-green Macaw (Ara chloropterus) was presented with regurgitation and passage of undigested seeds in the feces. Radiographic examination revealed dilatation of the proventriculus. Contrast radiography was performed and revealed that the proventricular dilatation and associated clinical signs resulted from circumferential thickening of the proventricular wall leading to severe narrowing of the lumen of the proventriculus. Testing for parrot bornavirus (PaBV) was negative. After the initiation of antimicrobial treatment because of suspected bacterial overgrowth, all clinical signs resolved two weeks after the start of the treatment, and radiographs taken four months after initial presentation revealed a normal appearance and size of the proventriculus. In the present case, bacterial proventriculitis associated with hyperplasia of the proventricular wall was put forward as a final but presumptive diagnosis highlighting the need to differentiate bacterial proventriculitis from other causes of proventricular dilatation in macaws

An atypical case of proventricular dilatation disease in a red-and-green macaw (Ara chloropterus)

A Red-and-green Macaw (Ara chloropterus) was presented with regurgitation and passage of undigested seeds in the feces. Radiographic examination revealed dilatation of the proventriculus. Contrast radiography was performed and revealed that the proventricular dilatation and associated clinical signs resulted from circumferential thickening of the proventricular wall leading to severe narrowing of the lumen of the proventriculus. Testing for parrot bornavirus (PaBV) was negative. After the initiation of antimicrobial treatment because of suspected bacterial overgrowth, all clinical signs resolved two weeks after the start of the treatment, and radiographs taken four months after initial presentation revealed a normal appearance and size of the proventriculus. In the present case, bacterial proventriculitis associated with hyperplasia of the proventricular wall was put forward as a final but presumptive diagnosis highlighting the need to differentiate bacterial proventriculitis from other causes of proventricular dilatation in macaws

Soft dentin results in unique flexible teeth in scraping catfishes

Teeth are generally used for actions in which they experience mainly compressive forces acting toward the base. The ordered tooth enamel(oid) and dentin structures contribute to the high compressive strength but also to the minor shear and tensile strengths. Some vertebrates, however, use their teeth for scraping, with teeth experiencing forces directed mostly normal to their long axis. Some scraping suckermouth catfishes (Loricariidae) even appear to have flexible teeth, which have not been found in any other vertebrate taxon. Considering the mineralized nature of tooth tissues, the notion of flexible teeth seems paradoxical. We studied teeth of five species, testing and measuring tooth flexibility, and investigating tooth (micro) structure using transmission electron microscopy, staining, computed tomography scanning, and scanning electron microscopy-energy-dispersive spectrometry. We quantified the extreme bending capacity of single teeth (up to 180 degrees) and show that reorganizations of the tooth (micro) structure and extreme hypomineralization of the dentin are adaptations preventing breaking by allowing flexibility. Tooth shape and internal structure appear to be optimized for bending in one direction, which is expected to occur frequently when feeding (scraping) under natural conditions. Not all loricariid catfishes possess flexible teeth, with the trait potentially having evolved more than once. Flexible teeth surely rank among the most extreme evolutionary novelties in known mineralized biological materials and might yield a better understanding of the processes of dentin formation and (hypo) mineralization in vertebrates, including humans