Publications by authors named "Wetzlich S"

Article Synopsis
  • The study investigates the safe withdrawal interval (WDI) for fenbendazole in pheasants, as its use is considered extra-label in the U.S.
  • Pheasants received fenbendazole medicated feed for 7 days, with tissue samples analyzed to determine drug metabolism and residue levels.
  • Results indicate a maximum WDI of 153 hours for certain muscles, establishing fenbendazole sulfoxide as a key residue marker in pheasant liver, supporting safe food practices.
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Florfenicol is a broad-spectrum antibiotic commonly used in the U.S. to treat respiratory and enteric infections in goats in an extra-label manner, which requires scientifically based withdrawal intervals (WDIs) for edible tissues.

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Florfenicol is a broad-spectrum antibiotic commonly prescribed in an extra-label manner for treating meat and dairy goats. Scientific data in support of a milk withdrawal interval recommendation is limited to plasma pharmacokinetic data and minimal milk residue data that is limited to cattle. Therefore, a rapid residue detection test (RRDT) could be a useful resource to determine if milk samples are free of drug residues and acceptable for sale.

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Meloxicam is a non-steroidal anti-inflammatory drug (NSAID) commonly prescribed in an extralabel manner for treating chickens in urbanized settings. The objectives of this study were to determine meloxicam depletion profiles in eggs and ovarian follicles and to estimate associated withdrawal intervals (WDI) in laying hens following a single intravenous or repeated oral administration. The observed peak concentration of meloxicam in ovarian follicles were consistently higher than in egg yolk and egg white samples.

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Meloxicam is commonly prescribed for treating chickens in backyard or small commercial operations despite a paucity of scientific data establishing tissue withdrawal interval recommendations following extra-label drug use (ELDU). Historically, ELDU withdrawal intervals (WDIs) following meloxicam administration to chickens have been based on the time when meloxicam concentrations fall below detectable concentrations in plasma and egg samples. To date, no studies have addressed tissue residues.

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Meloxicam is an anti-inflammatory drug used to treat pain and inflammation in ruminants including sheep, and pharmacokinetic studies are needed to protect the food supply from drug residues after use in food-producing animals. This study estimated plasma pharmacokinetic parameters and meat withdrawal intervals (WDI) for market sheep after multiple daily oral doses of meloxicam. Single and multiple dose plasma pharmacokinetic studies, a multi-dose tissue depletion study, and a follow-up study to investigate if events prior to slaughter were associated with differences in plasma meloxicam concentrations, all using sample data collected after completion of dosing, were completed.

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Ceftiofur crystalline free acid (CCFA) is a third-generation, oil-based, cephalosporin antimicrobial marketed as a once weekly treatment in cattle and swine, and as a two-time dose with 10-day duration in horses. Because handling and restraint times can be reduced, long-acting antibiotic preparations are particularly useful for treatment of nondomestic species. This study evaluated the pharmacokinetics of CCFA in ringneck doves ().

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OBJECTIVE To compare the pharmacokinetics of 2 commercial florfenicol formulations following IM and SC administration to sheep. ANIMALS 16 healthy adult mixed-breed sheep. PROCEDURES In a crossover study, sheep were randomly assigned to receive florfenicol formulation A or B at a single dose of 20 mg/kg, IM, or 40 mg/kg, SC.

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The objective of this study was to determine the pharmacokinetics of single- and multi-dose ceftiofur crystalline-free acid (CCFA) administered subcutaneously at a dose of 13.2 mg/kg to 12 neonatal foals 1-3 days of age. Six foals received a single subcutaneous dose, while 6 additional foals received 4 doses of CCFA at 48-h intervals.

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OBJECTIVE To describe plasma pharmacokinetic parameters and tissue elimination of flunixin in veal calves. ANIMALS 20 unweaned Holstein calves between 3 and 6 weeks old. PROCEDURES Each calf received flunixin (2.

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Ring-necked pheasants raised on propagation farms can be severely parasitized with Syngamus trachea (gapeworm) and other parasitic worms. Fenbendazole is a highly effective benzimidazole-class anthelmintic that is not currently approved for game bird species in the United States. The objective of this work was to provide target animal safety data to support a label claim for fenbendazole in pheasants at 100 parts per million (ppm) in the feed for 7 consecutive days.

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Objective: To determine the pharmacokinetics of ceftiofur crystalline-free acid (CCFA) following SC administration of a single dose to sheep.

Animals: 9 healthy adult female Suffolk-crossbred sheep.

Procedures: Each sheep was administered 6.

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Eight adult female dairy goats received one subcutaneous administration of tulathromycin at a dosage of 2.5 mg/kg body weight. Blood and milk samples were assayed for tulathromycin and the common fragment of tulathromycin, respectively, using liquid chromatography/mass spectrometry.

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Eight cattle (288 ± 22 kg) were treated with 2.2 mg/kg of body weight of flunixin free acid in a crossover design by subcutaneous (SC) and intravenous (IV) administration. After a minimum 1:10 dilution with 50 mM phosphate buffer, a commercial immunoassay was adapted to determine plasma concentrations of flunixin.

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Objective: To determine the tissue depletion profile of tulathromycin and determine an appropriate slaughter withdrawal interval in meat goats after multiple SC injections of the drug.

Animals: 16 healthy Boer goats.

Procedures: All goats were administered tulathromycin (2.

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Objective: To determine the pharmacokinetic properties of 1 IM injection of ceftiofur crystalline-free acid (CCFA) in American black ducks (Anas rubripes).

Animals: 20 adult American black ducks (6 in a preliminary experiment and 14 in a primary experiment).

Procedures: Dose and route of administration of CCFA for the primary experiment were determined in a preliminary experiment.

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Six adult male alpacas received one subcutaneous administration of ceftiofur crystalline free acid (CCFA) at a dosage of 6.6 mg/kg. After a washout period, the same alpacas received three subcutaneous doses of 6.

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The objective of this study was to determine the pharmacokinetics of CCFA in mares with placentitis and evaluate the disposition of the drug in fetal fluids, fetal membranes, colostrum, and serum of foals. A secondary objective was to obtain pilot data regarding the efficacy of CCFA for improving foal survival in mares with placentitis. Twelve pregnant pony mares were enrolled in the study, inoculated with Streptococcus zooepidemicus, intracervically and assigned to one of three groups: CEFT (n = 3; administered CCFA only; 6.

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Tulathromycin is a macrolide antimicrobial labeled for treatment of bacterial pneumonia in cattle and swine. The purpose of the present research was to evaluate tissue concentrations of tulathromycin in the caprine species. A tandem mass spectrometry regulatory analytical method that detects the common fragment of tulathromycin in cattle and swine was validated with goat tissues.

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Tulathromycin, a novel triamilide in the macrolide class, is labeled for treatment of bacterial pneumonia in cattle and swine. This manuscript evaluates pharmacokinetics of tulathromycin in goats. In two different studies, six juvenile and ten market-age goats received a single injection of 2.

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Six nonlactating and six lactating adult female goats received a single subcutaneous injection of ceftiofur crystalline free acid (CCFA) at a dosage of 6.6 mg/kg. Blood samples were collected from the jugular vein before and at multiple time points after CCFA administration.

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Ceftiofur, a third generation cephalosporin, demonstrates in vitro efficacy against microorganisms isolated from septicemic neonatal foals. This pharmacokinetic study evaluated the intravenous and subcutaneous administration of ceftiofur sodium (5 mg/kg body weight; n = 6 per group) and subcutaneous administration of ceftiofur crystalline free acid (6.6 mg/kg body weight; n = 6) in healthy foals.

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Progesterone (P4)-impregnated intravaginal controlled internal drug-releasing devices (CIDRs) have been used worldwide for estrus synchronization in ruminants. CIDRs serve to place all treated animals in the luteal phase of the estrous cycle. The objectives of this study were to compare P4 concentrations in milk from normal reproductively cycling, CIDR-treated, and pregnant goats.

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Tulathromycin is a triamilide antibiotic that maintains therapeutic concentrations for an extended period of time. The drug is approved for the treatment of respiratory disease in cattle and swine and is occasionally used in goats. To investigate the pharmacokinetics of tulathromycin in meat goats, 10 healthy Boer goats were administered a single 2.

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A physiologically based pharmacokinetic (PBPK) model was developed for midazolam in the chicken and extended to three other species. Physiological parameters included organ weights obtained from 10 birds of each species and blood flows obtained from the literature. Partition coefficients for midazolam in tissues vs.

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