Physiological parameter values for physiologically based pharmacokinetic models in food-producing animals. Part II: Chicken and turkey.

Physiologically based pharmacokinetic (PBPK) models are growing in popularity due to human food safety concerns and for estimating drug residue distribution and estimating withdrawal intervals for veterinary products originating from livestock species. This paper focuses on the physiological and anatomical data, including cardiac output, organ weight, and blood flow values, needed for PBPK modeling applications for avian species commonly consumed in the poultry market. Experimental and field studies from 1940 to 2019 for broiler chickens (1-70 days old, 40 g - 3.

Physiological parameter values for physiologically based pharmacokinetic models in food-producing animals. Part I: Cattle and swine.

Physiologically based pharmacokinetic (PBPK) models for chemicals in food animals are a useful tool in estimating chemical tissue residues and withdrawal intervals. Physiological parameters such as organ weights and blood flows are an important component of a PBPK model. The objective of this study was to compile PBPK-related physiological parameter data in food animals, including cattle and swine.

and Synergistic Effects of Florfenicol and Thiamphenicol in Combination Against Swine and .

Potential synergism between florfenicol (FF) and thiamphenicol (TAP) was investigated for efficacy against and/or as well as efficacy in swine. Among isolates of ( = 58) and ( = 79) from pigs in Taiwan that were tested, high percentages showed resistance to FF (52 and 53%, respectively) and TAP (57 and 53%, respectively). Checkerboard microdilution assay indicated that synergism [fractional inhibitory concentration index (FICI) ≤ 0.

Integration of Food Animal Residue Avoidance Databank (FARAD) empirical methods for drug withdrawal interval determination with a mechanistic population-based interactive physiologically based pharmacokinetic (iPBPK) modeling platform: example for flunixin meglumine administration.

Violative chemical residues in animal-derived food products affect food safety globally and have impact on the trade of international agricultural products. The Food Animal Residue Avoidance Databank program has been developing scientific tools to provide appropriate withdrawal interval (WDI) estimations after extralabel drug use in food animals for the past three decades. One of the tools is physiologically based pharmacokinetic (PBPK) modeling, which is a mechanistic-based approach that can be used to predict tissue residues and WDIs.

Increased Abundance of Lactobacillales in the Colon of Beta-Adrenergic Receptor Knock Out Mouse Is Associated With Increased Gut Bacterial Production of Short Chain Fatty Acids and Reduced IL17 Expression in Circulating CD4 Immune Cells.

Emerging evidence suggests an associative link between gut dysbiosis, the autonomic nervous system (ANS) and the immune system in pathophysiology of neurogenic hypertension (HTN). However, the close interplay between these three systems presents us with difficulties in deciphering the cause-effect relationship in disease. The present study utilized beta 1 and 2 adrenergic receptor knock out (AdrB1AdrB2/J KO) mice to isolate the effects of reduced overall sympathetic drive on gut microbiota and systemic immune system.

Assessment of veterinary drugs in plants using pharmacokinetic approaches: The absorption, distribution and elimination of tetracycline and sulfamethoxazole in ephemeral vegetables.

The present study was carried out to demonstrate novel use of pharmacokinetic approaches to characterize drug behaviors/movements in the vegetables with implications to food safety. The absorption, distribution, metabolism and most importantly, the elimination of tetracycline (TC) and sulfamethoxazole (SMX) in edible plants Brassica rapa chinensis and Ipomoea aquatica grown hydroponically were demonstrated and studied using non-compartmental pharmacokinetic analysis. The results revealed drug-dependent and vegetable-dependent pharmacokinetic differences and indicated that ephemeral vegetables could have high capacity accumulating antibiotics (up to 160 μg g-1 for TC and 38 μg g-1 for SMX) within hours.

Effect of lidocaine on inflammation in equine jejunum subjected to manipulation only and remote to intestinal segments subjected to ischemia.

OBJECTIVE To examine effects of continuous rate infusion of lidocaine on transmural neutrophil infiltration in equine intestine subjected to manipulation only and remote to ischemic intestine. ANIMALS 14 healthy horses. PROCEDURES Ventral midline celiotomy was performed (time 0).

Shifts in the Gut Microbiota Composition Due to Depleted Bone Marrow Beta Adrenergic Signaling Are Associated with Suppressed Inflammatory Transcriptional Networks in the Mouse Colon.

The brain-gut axis plays a critical role in the regulation of different diseases, many of which are characterized by sympathetic dysregulation. However, a direct link between sympathetic dysregulation and gut dysbiosis remains to be illustrated. Bone marrow (BM)-derived immune cells continuously interact with the gut microbiota to maintain homeostasis in the host.

Egg residue considerations during the treatment of backyard poultry.

The purpose of this digest was to provide US veterinarians guidance on the responsible treatment of backyard poultry flocks. The treatment of backyard poultry can be a daunting task for veterinarians because only limited resources are available; however, it is likely to become an increasingly common task owing to the increasing popularity of backyard poultry throughout the United States, especially in urban and suburban areas. Although backyard poultry flock owners may consider their birds pets, the FDA considers them food-producing animals, and veterinarians should follow all regulations that pertain to food-producing animals when administering or prescribing drugs to those birds.

Detection of undeclared animal by-products in commercial canine canned foods: Comparative analyses by ELISA and PCR-RFLP coupled with slab gel electrophoresis or capillary gel electrophoresis.

Background: The potential presence of undeclared animal by-products in pet foods is not subject to routine examination. Previously published methods for species-based identification of animal by-products have not been used routinely owing to inconsistent results. The present study evaluated the utility of several approaches for accurate identification of animal by-products in 11 commercial brands of canine canned foods.

Improved nonaqueous capillary electrophoresis for tetracyclines at subparts per billion level.

A NACE method with laser-induced fluorescence detection was modified for sensitive detection of 4 tetracyclines (TCs) in biological samples and feeds. The changes in injection mode, injection times, id of capillary, excitation wavelength, and the use of surfactant and sample stacking technique all contributed to improved LODs of TCs to sub-ng/mL level. With the optimized conditions, the instrumental LODs could reach 1.

Liquid chromatography incorporating ultraviolet and electrochemical analyses for dual detection of zeranol and zearalenone metabolites in mouldy grains.

Background: Zeranol (Z) is a semi-synthetic mycotoxin that is used in some countries as a growth-promoting agent in livestock. In view of the known oestrogenic actions by Z and certain Z analogues, significant concerns exist with regard to the presence of Z residues in human foods and the potential for untoward effects, including carcinogenicity within the reproductive system. In order to confirm that foods are free from harmful Z residues, regulators need a quick and reliable analytical method that can be used for routine confirmation of Z-positive samples identified by enzyme-linked immunosorbent assay (ELISA) screening.

Pharmacokinetics of clarithromycin and concentrations in body fluids and bronchoalveolar cells of foals.

Objective: To determine pharmacokinetics of clarithromycin and concentrations in body fluids and bronchoalveolar (BAL) cells of foals.

Animals: 6 healthy 2-to 3-week-old foals.

Procedures: In a crossover design, clarithromycin (7.

Fast differentiation of meats from fifteen animal species by liquid chromatography with electrochemical detection using copper nanoparticle plated electrodes.

A simple, rapid and reliable method based on high-performance liquid chromatography with electrochemical detection was developed to routinely differentiate among meat products from fifteen food animal species. Samples from cattle, pigs, goats, deer, horses, chickens, ducks, ostriches, salmon, cod, shrimp, crabs, scallops, bullfrogs and alligators each exhibited unique electrochemical profiles. Species-specific markers exhibited reproducible peak retention times with coefficients of variation less then 6% across different runs, body regions and subjects.

Antagonism of adenosine receptors by caffeine and caffeine metabolites in equine forebrain tissues.

Objective: To determine the presence of adenosine receptor subtypes A1 and A2a in equine forebrain tissues and to characterize the interactions of caffeine and its metabolites with adenosine receptors in the CNS of horses.

Sample Population: Brain tissue specimens obtained during necropsy from 5 adult male research horses.

Procedure: Membrane-enriched homogenates from cerebral cortex and striatum were evaluated by radioligand binding assays with the A1-selective ligand [3H]DPCPX and the A2a-selective ligand [3H]ZM241385.

In vivo monitoring of amino acids by direct sampling of brain extracellular fluid at ultralow flow rates and capillary electrophoresis.

Extracellular levels of glutamate (GLU), aspartate (ASP), glycine (GLY), phosphoethanolamine (PEA), and gamma-aminobutyric acid (GABA) were measured in the striatum of anesthetized rats using a novel sampling approach in which extracellular fluid (ECF) was removed at 1-50 nl/min using a fused silica capillary tube with 18-40 microm inner diameter and a outer diameter of 90 microm. The samples of ECF were analyzed by capillary electrophoresis with laser-induced fluorescence detection. Basal levels for GABA, GLY, and GLU measured using direct sampling at 1 nl/min were 270 +/- 40, 4950 +/- 1100, and 1760 +/- 150 nM, respectively in good agreement with the values obtained using microdialysis sampling calibrated by the low-flow rate method.