Frequency of arrhythmias detected in 9440 feline electrocardiograms by breed, age, and sex.

OBJECTIVES: The purpose of this study was to describe the frequency of arrhythmias detected in unsedated feline patients from general practice settings. ANIMALS: A total 10,638 feline electrocardiograms (ECGs) were retrospectively collected of which 9440 met the inclusion criteria. METHODS: Recordings were evaluated by a board-certified cardiologist. If an arrhythmia was present in the ECG tracing, the cardiologist categorized the arrhythmia using pre-established keywords. RESULTS: At least one arrhythmia was observed in 249 cases (2.64%, 95% confidence interval (CI): 2.34-2.98, 249/9440), with the most common arrhythmia encountered being ventricular premature complexes (1.63%, 95% CI: 1.39%-1.91%, 154/9440). Ragdoll cats had the highest odds of arrhythmia (odds ratio (OR): 3.17, 95% CI: 1.43-6.17, P=0.036). Both geriatric (Age: 13+ years, OR: 1.70, 95% CI: 1.24-2.34, P=0.013) and senior (Age: 10-13 years, OR: 1.68, 95% CI: 1.19-2.37, P=0.003) cats had higher odds of having an arrhythmia than adult cats. The odds of male cats having an arrhythmia were slightly higher than female (OR: 1.36, 95% CI: 1.06-1.76, P=0.018). CONCLUSIONS AND RELEVANCE: Of the 9440 ECGs included in this study, at least one arrhythmia was detected in 249 distinct cases. Arrhythmias were more common in older cats, male cats and the Ragdoll cat breed. While it is important to note that the presence of an arrhythmia alone does not always indicate the presence of heart disease, further research on the association between breed cardiac health is needed.

agr-Amanitin Tolerance in Mycophagous Drosophila.

Six species of Drosophila were tested for tolerance to the mushroom toxin alpha-amanitin, a potent inhibitor of RNA polymerase II. Three nonmycophagous species-D. melanogaster, D. immigrans, and D. pseudoobscura-showed very low survival and long development times in the presence of amanitin. Three mycophagous species-D. putrida, D. recens, and D. tripunctata-showed little or no sensitivity. Analysis in vitro indicated that this tolerance is not based on alteration of the molecular structure of RNA polymerase II.

The oldest fossil bee: Apoid history, evolutionary stasis, and antiquity of social behavior.

Trigona prisca, a stingless honey bee (Apidae; Meliponinae), is reported from Cretaceous New Jersey amber (96-74 million years before present). This is about twice the age of the oldest previously known fossil bee, although Trigona is one of the most derived bee genera. T. prisca is closely similar to modern neotropical species. Most of bee evolution probably occurred during the approximately 50 million years between the beginning of the Cretaceous when flowering plants (on which bees depend) appeared and the time of T. prisca. Since then, in this phyletic line of Meliponinae, there has been almost no morphological evolution. Since the fossil is a worker, social organization had arisen by its time.