1. Tetracyclines are among the most widely used antibiotics in poultry, with oxytetracycline (OTC) playing a key role due to its routine administration via feed and water to treat susceptible bacterial infections. Despite its widespread clinical use, understanding of the pharmacokinetics of OTC in the genus Anas remains remarkably limited. The following study characterised the pharmacokinetic profile of OTC after intravenous (IV), intramuscular (IM), subcutaneous (SC) and oral administration in ducks (Anas platyrhynchos).2. A total of 24 ducks (six per group in a parallel study) were given OTC at a dose of 40 mg/kg via IV, IM, SC and oral routes. Blood samples were collected at various time points ranging from 0 min (control) to 96 h post-administration. The samples were examined by high-performance liquid chromatography (HPLC) and the pharmacokinetic parameters were assessed through non-compartmental analysis.3. Following IV administration, the volume of distribution (2.73 l/kg) suggested extensive tissue penetration. Elimination half-lives were 12.69 h (IM), 13.54 h (SC) and 12.62 h (oral), all slightly longer than after IV dosing (9.72 h) with no significant differences between extravascular routes. Bioavailability was high after parenteral administration (≈90-98%), suggesting near-complete absorption, whereas oral bioavailability was low (≈17%), indicating gastrointestinal absorption as the main limiting factor. Plasma protein binding was high (87-93%).4. Parenteral administration of OTC (40 mg/kg) in ducks can achieve effective exposure against pathogens with minimum inhibitory concentration (MIC) ≤0.5 µg/ml.
1. The following study investigated the effects of a standardised Peganum harmala L. (PH) extract on post-hatch behaviour, environmental adaptation, incubation performance and eggshell disinfection in Japanese quail (Coturnix japonica).2. A total of 520 fertile eggs were utilised in the experiment, with 130 eggs randomly assigned to each of the four treatment groups: distilled water (P1), ethanol (P2), 1% PH extract (P3) or 5% PH extract (P4) appliedviaactive humidification on d 1, 3, 7 and 14 of incubation. Analysis by GC-MS was used to identify peganine and quinazoline alkaloids as the primary bioactive components of the PH extract.3. Behavioural assessments (Open Field and Runway tests) showed shorter behavioural latency and enhanced exploratory behaviour in chicks exposed to PH extract compared with controls.4. Microbial analysis showed that the 5% extract (P4) achieved the lowest bacterial load on day 10 compared with P1 (p < 0.05). The eggs in the P4 group had the highest fertile hatchability and chick quality scores among the treatment groups.5. Standardised PH extract represents a promising botanical disinfectant associated with favourable behavioural outcomes in newly hatched chicks, with potential applications for hatchery management.
