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We show that annealing of stoichiometric $\mathrm{Sr}\mathrm{Ru}{\mathrm{O}}_{3}$ perovskites in high-pressure oxygen of $600\phantom{\rule{0.3em}{0ex}}\mathrm{atm}$ near $1100\phantom{\rule{0.2em}{0ex}}\ifmmode^\circ\else\textdegree\fi{}\mathrm{C}$ produces $\mathrm{Sr}{\mathrm{Ru}}_{1\ensuremath{-}v}{\mathrm{O}}_{3}$ compounds with vacancies on the Ru-sites. The creation of Ru vacancies rapidly suppresses the ferromagnetic ordering temperature, ${T}_{C}$, from $163\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ to $45\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ with an increase of $v\ensuremath{\approx}0.09$. Subtle structural changes that accompany the creation of Ru-site vacancies are different from the typical properties of transition metal perovskites, for which an increased formal oxidation state of the B-site cations normally leads to decreased B-O interatomic distances and contraction of the unit cell volume. The reduced charge screening caused by the Ru-vacancies offsets an expected decrease of the average interatomic distance Ru-O and rotation of the $\mathrm{Ru}{\mathrm{O}}_{6}$ octahedra as Sr atoms relax toward Ru-vacancies increases the observed volume.

Calves experimentally infected with Eimeria bovis and E zuernii were used in a controlled experiment to determine the anticoccidial activity of lasalocid sodium. Eleven-week-old Holstein calves were given an inoculum of 300,000 E bovis and 200,000 E zuernii oocysts; medication was initiated on the day of inoculation and continued for a 4-week period. The progress of parasitic infection was monitored with quantitative fecal oocyst examinations for the 6 weeks before calves were inoculated, and then in the 4-week treatment period and a 3-week observation period. The calves were given different doses of lasalocid sodium (0.5, 0.75, 1.0, and 3.0 mg/kg) and were compared with both nonmedicated inoculated calves and controls (nonmedicated, noninoculated calves). There were overall numerical reductions of oocysts produced in the medicated groups when compared with the nonmedicated inoculated controls.