Use of a quantitative strong ion approach to determine the mechanism for acid-base abnormalities in sick calves with or without diarrhea.

Acid-base abnormalities are frequently present in sick calves. The mechanism for an acid-base disturbance can be characterized using the strong ion approach, which requires accurate values for the total concentration of plasma nonvolatile buffers (A(tot)) and the effective dissociation constant for plasma weak acids (K(a)). The aims of this study were to experimentally determine A(tot), K(a), and net protein charge values for calf plasma and to apply these values quantitatively to data from sick calves to determine underlying mechanisms for the observed acid-base disturbance.

Efficacy of spectinomycin against Mycoplasma bovis induced pneumonia in conventionally reared calves.

Sixteen 3-week-old calves were intratracheally inoculated with Mycoplasma bovis. Follow-up consisted of regular bronchoalveolar lavages (BALs) and clinical examinations. Animals were slaughtered from 4 to 21 days after inoculation.

[Molecular epidemiology or bovine rotaviruses from the Charolais area].

Molecular epidemiology of bovine rotavirus from the Charolais area (France). Faecal samples from 164 diarrhoeic calves under 60 days of age were collected from the Charolais area of France during winter of 1998. The samples were tested by an enzyme-linked immunosorbent assay (ELISA) to detect the presence of rotavirus antigen.

Plasma bioavailability of 2 long-acting oxytetracycline formulations in the pig.

Two commercially available long-acting oxytetracycline (OTC-LA) formulations were administered by intramuscular injection in 2 groups of 10 clinically healthy pigs at the recommended dose level of 20 mg/kg. Plasma concentrations were analysed by high-performance liquid chromatography (HPLC) of a period of 0 to 84 h. The limit of quantification of the assay was 0.