Analysis of the right ventricular function in the exercising horse: use of the Fourier Transform

The objective of this study was to develop and test a technique to allow dynamic cardiac function to be studied during exercise in the horse. Blood pressure waveforms in the exercising horse are difficult to interpret because of the large influence of stride and respiration. A method has been devised to study dynamic right ventricular variables during high-speed exercise in the horse. A Fast Fourier Transform was performed on the digitised pressure waveforms and the frequency components associated with stride and respiration were removed. An inverse Fourier Transform was then performed to generate a time-domain pressure signal. Several dynamic right ventricular variables were calculated using the derived signal. Various parameters associated with removing frequencies from the frequency-domain pressure signal were changed to determine their influence on the variables. Most of the variables were not sensitive to these parameters. When compared during separate exercise bouts, some variables differed among runs, while others were not significantly different. Using the signal separation technique described here, right ventricular function of an exercising horse can be critically analysed.     

Retracted: Effect of Post‐Thaw Storage Time on Motility and Fertility of Cryopreserved Beluga Sturgeon (Huso huso) Sperm

The aim of this study was to test the influence of post ‐ thaw storage time on the duration of sperm motility, percentage of motile sperm, and fertilization and hatching rates of fresh sperm and sperm stored for 0, 30 and 60 min at 4°C post‐thawing. After being frozen in liquid nitrogen and then thawed, the percentage of motile sperm and duration of motility were not affected by 30 min of storage at 4°C, whereas a significant decline in these parameters was observed after 60 min of storage. Similarly, fertilization and hatching rates were significantly affected within 60 min of storage at 4°C, and the fertility of frozen‐thawed sperm was significantly lower than that of fresh sperm. We conclude that cryopreserved sperm of beluga sturgeon could be stored for 30 min without the loss of sperm quality. This described procedure for beluga sturgeon cryopreservation is reliable and efficient and therefore can be recommended for hatchery practice after scaling up this technique.     

Rhodococcus equi-associated osteomyelitis in foals

Two cases of Rhodococcus equl infection in foals are described, in which osteomyelitis was a feature. Because rhodococcal infection is usually low grade and chronic, and because the signs of early metaphysitis can be subtle, any articular or periarticular swelling in a foal from a farm with a history of rhodococcosis should be strongly suspected to be associated with R equl until proven otherwise.     

Blood gas analyses on equine blood: required correction factors [see comment]

Correction factors have been determined to obtain the best estimates of PO2, PCO2 and pH in equine blood with standard blood gas and pH electrodes. There was a significant difference between the PO2 readings for tonometred blood of most horses and the equilibrating gas. Thus, if the PO2 electrode is calibrated with a gas, an electrode correction factor should be obtained by tonometring a blood sample from each horse. This factor was not dependent on packed cell volume. No such correction is required for the PCO2 electrode. If the animal's temperature differs from that of the analyser, the PO2, PCO2 and pH values must be corrected to the animal's body temperature. Temperature correction factors determined for equine blood were similar to those for human blood. Failure to make temperature corrections can result in errors for PO2 and PCO2 of 6 to 7 per cent per degree of temperature difference.     

Squamous cell carcinoma in a tuatara (Sphenodon punctatus)

CASE HISTORY: A mature male tuatara was presented with a history of recurrent cloacal prolapse.

CLINICAL AND PATHOLOGICAL FINDINGS: The prolapsed tissue included a 12 mm diameter mass, which histologically showed cords and nodules of neoplastic epithelial cells.

DIAGNOSIS: The mass was diagnosed as a squamous cell carcinoma with ulceration of the overlying stratified squamous epithelium and diffuse inflammation of the surrounding dermis.

CLINICAL RELEVANCE: This case presented a rare opportunity to investigate squamous cell carcinoma in a long-lived lower vertebrate species. Future recurrence or metastasis of the mass may add useful information to the current base of knowledge of the behaviour of malignant neoplasms in reptiles.     

Bacterial sinusitis as a cause of beak deformity in an Antipodes Island parakeet (Cyanoramphus unicolor)

CASE HISTORY: From 26 days of age, an Antipodes Island parakeet (Cyanoramphus unicolor) was noted to have a severe beak deformity and reduced bodyweight gain compared to its nest mate. The bird was euthanised at 43 days of age.

CLINICAL AND PATHOLOGICAL FINDINGS: The beak abnormality consisted of distortion of the right nares and severe shortening resulting in deviation of the upper maxilla to the right and cranially. On sectioning the head, copious mucoid material was found in the infraorbital sinus and the bony sinus architecture was disrupted. Histopathological examination of the infraorbital sinuses revealed a large focus of chronic but active inflammation, bony lysis on the right side and pockets of a mixed population of bacteria.

DIAGNOSIS: Severe beak deformity, likely secondary to bacterial sinusitis.

CLINICAL RELEVANCE: The case illustrates the need to look for underlying aetiologies to beak malformation, particularly in young parrots.