Validated Stability Indicating Chromatographic Methods for Quantification of Imidocarb Dipropionate; Application for the Determination of Its Residues in Bovine Meat and Milk Samples.

BACKGROUND: Imidocarb dipropionate (IMD) is an immunomodulator agent commonly used for treatment of anaplasmosis in cattle. OBJECTIVE: Thus, two sensitive, specific, and precise stability-indicating chromatographic methods have been developed, optimized, and validated for its determination in presence of its acid, alkaline, and oxidative stressed degradation products. METHOD: The first method is based on separation of IMD and its forced induced degradation products on reversed phase cyano column using isocratic elution system consisted of sodium acetate buffer-methanol-acetonitrile (55: 30:15, v/v/v), pH 4.6 at a flow rate of 1.2 mL/min, and UV detection at 254 nm. The second method utilized TLC combined with densitometric determination of the separated bands at 254 nm. The separation was achieved using silica gel 60 F254 TLC plates with a mixture of ethyl acetate-methanol-ammonia-water (8.5:1:0.5:0.2, v/v/v/v) as a developing system. RESULTS: HPLC analysis was applied in range of 0.25-40 µg/mL with LOD of 0.073 µg/mL. While densitometric measurements showed linearity in the range of 0.1-1.8 µg/band with LOD of 0.02 µg/band. CONCLUSIONS: The suggested methods were validated in compliance with the ICH guidelines and were successfully applied for determination of IMD in its commercial veterinary formulations with good recoveries. Furthermore, the proposed HPLC method was extended to the determination of IMD residues in bovine meat and milk samples. HIGHLIGHTS: Bovine meat, HPLC, Imidocarb dipropionate, Milk, TLC.

Light and Scanning Electron Microscopic Examination of the Chicken Oviduct during the Embryonic and Posthatching Stages.

The present study aimed to study the sequence of developing the oviduct of the Alexandria chicken during the embryonic and posthatching period by using the light and scanning electron microscopic (SEM) examination. The Mullerian duct began to appear as left and right urogenital ridges composed of stratified cuboidal epithelium at the ventrolateral aspect of the mesonephros at the 5-day-old embryo. At the 6-day-old embryo, the left urogenital ridge canalized and the tubal wall surrounded a circular lumen composed of three cellular components; inner simple columnar epithelium, multilayers of mesenchymal cells, and outer stratified cuboidal epithelium. At the 8-day-old embryo, the inner tubal layer became composed of simple-to-pseudostratified ciliated columnar epithelium, the density of the mesenchymal cells increased, and the outer layer became simple squamous epithelium at the medial aspect of the duct and stratified epithelium at the lateral aspect of the duct. The left oviduct of the 1-day-old chick resembled the oviduct of 8-day-old embryo except the SEM observations of the tunica mucosa of the 1-day-old chick which showed extensive mucosal folds with many straight cilia. At the 1-week-old chick, the left oviduct showed a folded lumen surrounded by simple columnar ciliated epithelial layer followed by a layer of mesenchymal cells, many layers of smooth muscles surrounded the mesenchymal cells layer and outer simple squamous epithelium layer. At the 1-month-old chick, the left oviduct wall was composed of five layers surrounded by a star-shaped lumen.