2011 - 80 (2)

The syrinx plays an important role in the sound production of birds. Its most important structures are the labiaand the lateral tympaniform membranes that produce sound by vibrating during expiration. Since the left and rightsides of the syrinx are innervated independently from each other, two sound sources are present which can act eithersimultaneously or separately with one side acting as sound source and the other side as air inlet. The bird’s song isgenerated in specific neural brain centres via a seamless synchronization of the respiration and the muscles of theupper respiratory tract, the trachea and the syrinx. Hormones also play a role by influencing the volume of the braincentres in relation to the season. The acquisition of the bird’s song starts with a sensory phase in which the juvenilebird learns the species specific song, and is followed by a sensorimotor phase during which the young bird finetunesits song via auditory feedback.

Paper in Dutch

Paper in Dutch

Paper in Dutch

Neurological diseases caused by neuropathogenic strains of EHV1 are being reported with increasingfrequency. Consequently, concern is being voiced within the US horse industry that the neurologic form ofEHV1 may be intensifying in prevalence and/or morbidity and mortality. In Belgium, outbreaks of EHV1-induced abortions are an annually recurrent phenomenon, but outbreaks of equine herpes myelitis (EHM) arerare. This report describes an unusually large outbreak of EHV1-induced EHM that involved at least 13different premises. Seven of them were characterized in more detail and were included in this study. Amorbidity of 26% was seen, with an EHM incidence of 43% in the affected horses. The outbreak wascharacterized by rapid occurrence of ataxia and paralysis immediately after disappearance of the fever. EHV1was diagnosed by means of virus isolation and/or seroconversion. The isolated virus was classified either asneuropathogenic or as belonging to group 4 after sequencing in the ORF30 and ORF68 regions, respectively.The extent of this outbreak and the high percentage of neurological disease, along with the fact that EHMis only sporadically seen in Belgium, might indicate that the neurological form of EHV1 is possibly alsoemerging in Belgium.

Hyperadrenocorticism is a frequently occurring disease in middle-aged ferrets. It is caused by a neoplasm of theadrenal cortex. Otherwise than in dogs and cats, hyperadrenocorticism in the ferret is always independent ofadrenocorticotropic hormone (ACTH). The tumor of the adrenal cortex can be removed surgically, mostly withsatisfying results. After surgery, a regression of symptoms occurs after two to eight weeks, and the animals arewithout symptoms after five to eight months. In recent years, there has been a growing interest in using a chemicaltherapy aimed at decreasing hormone production through the administration of GnRH agonists. These agonistsinitially cause a temporary increase of the sex steroids, and then a long-term decrease of them through desensitizationof the GnRH receptors. A deslorelin implant seems to be a promising alternative for the surgical treatment ofhyperadrenocorticism in ferrets. Some authors even recommend it as a standard preventive treatment after neuteringin both genders and for every ferret over four years of age. Moreover, it is an excellent alternative for surgicalcastration.

Equine peripheral blood (ePB) can be used as a source of stem cells (SCs) in horses, both for research andfor practical purposes. A relatively low volume of ePB is sufficient for the purification and expansion of theSCs. The identification of the SCs is performed by demonstrating the presence (CD34, CD90, CD105 andCD117) or absence (CD14) of specific markers on the cell surface by means of fluorescent staining, followedby Fluorescence Activated Cell Sorting (FACS) for sorting out the desired population of SCs. The entire processof SC isolation and enrichment from ePB typically takes three days, after which the enriched SC sample canbe sent back to the patient for clinical application. The two most common clinical applications of SCs from ePBwill be demonstrated with two field cases. The first case presents a lesion of the body of the suspensory ligamentin a 13-year-old warmblood mare and the second case describes a bacterial ulcerative keratitis in a 20-yearoldwarmblood gelding.

Paper in Dutch

Kidney function investigations in veterinary medicine are traditionally based on blood analysis (bloodurea nitrogen (BUN) and serum creatinine concentration) and / or urinalysis (urine specific gravity, proteinto-creatinine ratio or fractional excretion). Morphologic information is usually obtained by abdominalradiography or ultrasonography. However, when more specific information on the functionality of the kidneysis needed, nuclear medicine offers various tracers that specifically represent glomerular filtration rate, effectiverenal plasma flow or functional renal mass, sometimes combining functional and morphologic data. Theseprocedures can be based on blood sampling techniques (non-imaging methods), or data can be obtained usinga gamma-camera (imaging methods). The most commonly used radionuclides for the examination of kidneyfunction in small animal medicine are discussed in this review.

Paper in Dutch