Butterfly feeding on lycopsid

Larvae of Euptychia westwoodi feed on Selaginella, a lycopsid. This is the first feeding record in the Satyrinae outside the monocotyledons and one of the few records of a butterfly feeding on other than a seed plant. Clues to possible evolutionary origins of this habit are found in the oviposition behavior of other Euptychia species.     

Efficacy and Toxicity of Tocainide for the Treatment of Ventricular Tachyarrhythmias in Doberman Pinschers With Occult Cardiomyopathy

Tocainide was administered to 23 cardiomyopathic Doberman Pinschers at doses of 15 to 25 mg/kg tid. These doses produced peak (2–hour) serum concentrations of 6.2 to 19.1 mg/L and trough (8–hour) serum concentrations of 2.3 to 11.1 mg/L. Anorexia and gastrointestinal disturbances occurred in 8 dogs (35%) at doses (15.6 to 25.0 mg/kg) that were not different from those (16.0 to 26.0 mg/kg) received by dogs that did not experience toxicity. Doses producing peak serum concentrations that were either greater or less than 14 mg/L were not different. Likewise, doses producing trough values that were either greater or less than 6 mg/L were not different. The mean dose that produced peak serum concentrations of 10 to 13.6 mg/L and trough concentrations of 4.2 to 10.0 mg/L was 17.9 mg/kg, and was associated with anorexia in 4 dogs. Mean peak serum concentrations associated with toxicity (14.4 mg/L) were significantly higher ( P = .02) than dogs not experiencing toxicity (11.8 mg/L). Serious adverse effects occurred in 7 of 12 dogs (58%) receiving tocainide for longer than 4 consecutive months. Progressive corneal endothelial dystrophy occurred in 3 dogs. Although a causal effect could not be proven, 6 dogs experienced renal dysfunction during treatment. Drug doses in these 7 dogs were similar to those received by other dogs. At least a 70% reduction of the total numbers of ventricular premature contractions occurred in 80% of dogs treated, and ventricular tachycardia was eliminated in 90% of affected dogs by the time of the first post-treatment Holter recording. Long-term control of ventricular tachyarrhythmias was difficult to achieve in some dogs when the left ventricular shortening fraction was less than approximately 17%. J Vet Intern Med 1996;10:235–240. Copyright © 1996 by the American College of Veterinary Internal Medicine .     

Observations on the laying behaviour of hens in battery cages

Observations were made on the laying behaviour of hens from each of two commercial strains kept in a Thornber battery cage system. Attention was paid to the following behavioural components of oviposition: the position of the hen in the cage; the stance of the hen; the height through which the egg fell; the orientation of the egg; the time taken to oviposit; the time taken for the egg to roll out of the cage and the incidence of pecking at the egg.

Less detailed observations were made on the pre‐laying behaviour of the hens.     

Effect of a gibberellin-biosynthesis inhibitor treatment on the physicochemical properties of sorghum starch

Inhibition of plant growth by Trinexapac-ethyl, TE, a gibberellin-biosynthesis inhibitor, can produce a shorter stemmed plant, requiring less nutrients and water to grow, while maintaining grain yield. Although TE and other plant growth regulators are commonly used in grain crops, their effects on starch biosynthesis in the grains have not been systematically examined. The changes in the structural and functional properties of starch in grains harvested from TE-treated sorghum (Sorghum bicolor (L.) Moench) were examined, and the results compared with those from the untreated controls. TE treatment had little or no effects on the molecular structures of starch, starch granule morphology, and starch and amylose contents, but increased the protein content of the grains significantly. Consistent with the lack of change in the molecular structure, there were no significant effects on the thermal properties of the starch. The pasting properties of TE-treated sorghum flours, however, showed lower peak viscosity, trough, and final viscosity, which were attributed to their higher protein contents. The TE treatment thus does not have an appreciable effect on the biosynthesis of starch during grain development in sorghum.