Comparative metabolic excretion profile of sodium salicylate in broiler chickens and homing pigeons

Doping in Racing Pigeons (Columba livia domestica): A Review and Actual Situation in Belgium, a Leading Country in This Field

Pigeon racing is a sport in which trained homing pigeons (Columba livia domestica) are released between 60 and 1200 km from their loft and then have to return home as quickly as possible. The first race was held in 1818 in Belgium and since then, Belgium has led the world in pigeon breeding. Unfortunately, as in other sports, doping has become a major issue and doping controls have been implemented. This review provides information about pigeon racing, rules from the Royal Federation Colombophile of Belgium, and laws applicable in Belgium as doping control issues cannot be understood without including them as part of pigeon racing. The main pharmacological data concerning corticoids, non-steroidal anti-inflammatory drugs, anabolic steroids, pain relievers and narcotic analgesics, bronchodilators and β-agonists, drugs acting on the central nervous system and other performance-enhancing drugs, in addition to methods relevant to doping in pigeons are presented. Moreover, the chosen matrix and analytical methods are described.

Residues of salicylic acid and its metabolites in hen plasma, tissues and eggs as a result of animal treatment and consumption of naturally occurring salicylates

Salicylates are among the most known anti-inflammatory drugs, used both in human and veterinary medicine. They also occur naturally in plants. Residues of salicylic acid in tissues and eggs may occur after drug administration or exposure of animals to feed material with high salicylate content. An animal study was performed on laying hens. The birds received sodium salicylate or acetylsalicylic acid (10 mg/kg b.w.) for 7 days or were given corn containing 1.18 mg/kg of salicylic acid. Samples of liver, muscle and plasma were collected at 0, 4, 8, 24 and 72 h after treatment; eggs were collected daily for 14 days. Salicylic acid and its metabolites: gentisic acid, salicyluric acid and gentisuric acid were determined using liquid chromatography coupled with tandem mass spectrometry. In both liver and muscle, the residues after administration of sodium salicylate were initially higher than for acetylsalicylic acid but they depleted at the same time. The deposition and depletion profile of salicylic acid in eggs was similar for groups receiving both drugs; the plateau level reached 248 ± 61.5 μg/kg and 275 ± 82.1 μg/kg. The concentration of salicylic acid in tissues and eggs of animals receiving salicylic acid was low. Gentisic acid was found in individual samples of liver, muscle and eggs from all treated groups. The exposure of hens to the salicylates at feed additive levels and to naturally occurring salicylates results in low residue concentrations and fast depletion of salicylic acid. The eggs do not pose any risk to consumers sensitive to salicylates.

The influence of rapid growth on sodium salicylate pharmacokinetics in male turkeys

The aim of this study was to assess the influence of growth on the pharmacokinetics of sodium salicylate (SS) in male turkeys. SS was administered intravenously at a dose of 50 mg/kg. Plasma drug concentrations were assessed by high-performance liquid chromatography, and pharmacokinetic parameters were calculated by noncompartmental analysis. As the age increased from 6 to 13 weeks (body weight increase from 2.35 to 9.43 kg), median body clearance decreased from 1.34 to 0.87 ml/min/kg. This caused a significant increase in the median mean residence time from 3.42 to 4.44 hr. Elimination phase proved to be biphasic and two elimination half-lives (T_1/2el ) were distinguished. Whereas T_1/2el1 was found to increase with age by 128%, T_1/2el2 represented a later but faster and less age-dependent phase of elimination (increase by 56% in the respective groups). Volume of distribution decreased with age. These effects may lead to different therapeutic response to SS in turkeys of different age and body weights.

Pharmacokinetics of repeated sodium salicylate administration to laying hens: evidence for time dependent increase in drug elimination from plasma and eggs

Salicylates were the first non-steroid anti-inflammatory drugs (NSAIDs) to be used in any species and are still widely used in humans and livestock. However, the data on their pharmacokinetics in animals is limited, especially after repeated administration. Evidence exist that in chickens (Gallus gallus) salicylate (SA) may induce its own elimination. The aim of this study was to investigate salicylate pharmacokinetics and egg residues during repeated administration of sodium salicylate (SS) to laying hens. Pharmacokinetics of SA was assessed during 14 d oral administration of SS at daily doses of 50 mg/kg and 200 mg/kg body weight to laying hens. On the 1st, 7th and 14th d a 24 h-long pharmacokinetic study was carried out, whereas eggs were collected daily. Salicylate concentrations in plasma and eggs were determined using high-performance liquid chromatography with ultraviolet detection and pharmacokinetic variables were calculated using a non-compartmental model. Mean residence time (MRT), minimal plasma concentration (Cmin, C16h) and elimination half-life (T1/2el) of SA showed gradual decrease in layers administered with a lower dose. Total body clearance (ClB) increased. Layers administered with the higher dose showed a decrease only in the T1/2el. In the low dose group, SA was found only in the egg white and was low throughout the experiment. Egg whites from the higher dose group showed initially high SA levels which significantly decreased during the experiment. Yolk SA levels were lower and showed longer periods of accumulation and elimination. Repeated administration of SS induces SA elimination, although this effect may differ depending on the dose and production type of a chicken. Decreased plasma drug concentration may have clinical implications during prolonged SS treatment.

Adverse effects associated with high-dose acetylsalicylic acid and sodium salicylate treatment in broilers

1. Acetylsalicylic acid (ASA) and sodium salicylate (SS) are considered safe for poultry and often used in avian medicine. However, information on tolerance and specific side effects of these drugs in birds is lacking. 2. The aim of this study was to determine the effects of 14 d administration of high doses (200 or 400 mg/kg) of either ASA or SS on body weight gain, blood biochemistry, white and red blood cell counts and pathology in broilers. In addition, minimal plasma salicylate concentrations were determined on the 1st, 5th, 10th and 14th d of treatment. 3. The results showed that the dose of 400 mg/kg of either ASA or SS decreased weight gain and induced gizzard ulceration. Kidney to body weight ratio was increased in a dose-dependent manner, but serum concentrations of creatinine and uric acid were not affected. A time-dependent decrease in the minimal plasma salicylate concentration was evident.

VEGF expression and the effect of NSAIDs on ascites cell proliferation in the hen model of ovarian cancer

OBJECTIVES

We aimed to determine the expression of vascular endothelial growth factor (VEGF) and the effect of nonsteroidal anti-inflammatory drugs (NSAIDs) on the proliferation of cells isolated from ascites in the hen model of ovarian cancer.

METHODS

Ovarian tumor and normal ovary were collected from hens and ascites cells were isolated from hens with ovarian cancer. Quantitative real-time PCR was used to quantify mRNA expression. Immunohistochemical and/or Western blot analyses were used to localize protein expression in ovarian tumors, normal ovaries, and ascites cells. Cells were treated with a nonspecific, COX-1-specific, or COX-2-specific NSAID and proliferation was determined.

RESULTS

VEGF mRNA was increased in ascites cells and there was a trend for a correlation between VEGF mRNA in ascites cells and ascites volume. VEGF protein was localized to theca cells of normal ovaries, in glandular areas of tumors, and to the cytoplasm of ascites cells. Aspirin and a COX-1-specific inhibitor decreased the proliferation of ascites cells, whereas a COX-2-specific inhibitor did not.

CONCLUSIONS

VEGF may play a role in ovarian cancer progression in the hen and the proliferation of ascites cells can be decreased by targeting the COX-1 but not COX-2 pathway.

Biopharmaceutic and pharmacokinetic studies following the oral administration of sodium salicylate in oily and aqueous vehicles to rabbit

The pharmacokinetic parameters, i.e. peak concentration (c(max)); peak time (t(max)); area under the curve (AUC); elimination rate constant (k); absorption rate constant (k(a)); Drug clearance (cl(t)), and the volume of distribution (v(d)) of sodium salicylate administered in fractionated coconut oil (FCO) have been compared with that from an aqueous and glycerin vehicles using a three-way crossover study in 12 rabbits. The results of the study show that all of the pharmacokinetic parameters tested differ significantly when administered in oily rather than aqueous or glycerin vehicles. No statistically significant difference was found between any of the above mentioned parameters when comparison was made between aqueous and glycerin formulations. The results indicate that sodium salicylate is absorbed at a lower rate but to a greater extent from oily formulation. Possible reasons for these differences are discussed and is suggested, therefore, that the oily formulation might be used as a sustained release preparation.