Disposition of gentamicin in the genital tract of cows*

Abstract

The distribution of gentamicin (G) in plasma and uterine lumen was studied following intramuscular (i.m.) and intrauterine (i.u.) treatment. A Foley catheter was inserted into one uterine horn and retained in place by inflation of the cuff. This provided a closed system for collection of uterine lumen samples and analysis of the concentration of gentamicin for 6 h following treatment. Four normal cycling and healthy cows in dioestrus were given i.m. injections of 4 mg gentamicin/kg BW and another two were given i.m. injections of 2 mg gentamicin/kg BW gentamicin. The uteri were infused with 50 ml saline containing phenolsulphonphthalein (PSP) indicator. Blood and infused solution (IS) samples were periodically collected during the 6-h period following i.m. administration. Six hours after injection, approximately 183.7 micrograms gentamicin and 39.4 micrograms gentamicin were accumulated in the uterine lumen of cows receiving 4 mg gentamicin/kg BW and 2 mg gentamicin/kg BW, respectively. The amount of gentamicin reaching the blood stream after i.m. administration of 4 mg gentamicin/kg BW was 2.89 times that reached after administration of 2 mg gentamicin/kg BW based on the area under the curve of plots of plasma concentration of gentamicin versus time. Four normal-cycling and healthy cows in dioestrus were given i.u. infusions of gentamicin (225-275 mg) diluted in 50 ml saline containing PSP indicator using a Foley catheter in a closed system. Samples from the IS and blood were collected at various intervals for 6 h after infusion. Following i.u. infusion of gentamicin, an average of 29.4% of the dose was absorbed into the bloodstream. The majority of the dose of gentamicin (70.6%) remained in the uterine lumen throughout the 6-h period.

Comparative pharmacokinetics of gentamicin, neomycin and oxytetracycline in newborn calves

“…Thus, the clearance of both drugs appears to be consistent with clearance by glomerular filtration at a similar rate in the neonate and older calf. The gentamicin elimination values are generally consistent with those reported (or calculated from data presented) for cattle, ranging from tlj2(f3) of approximately 76 to 240 min depending on age and route of administration (Carli et al, 1978;Ziv et al, 198 1, 1982;Al-Guedawy et al, 1983;Clarke et al, 1985). However, the lack of change in elimination rate with age in three of the four calves differs from the significant change reported by Clarke et al, (1985), in which case there was a small increase during the first 15 days of life but a marked difference when compared with mature cows.…”

Disposition of Trimethoprim — Sulphamethoxazole Combination Following Intrauterine Administration in Buffaloes

“…There is no report available in the literature to substantiate these findings but in a disposition study, oxytetracycline (OTC) was found to be poorly absorbed from the uterine lumen and the drug was not detectable in the genital tissues apart from the endometrium (MASERA et al, 1980). Similarly, gentamicin (250-275 mg in saline solution) has been reported (AL-GUEDAWY et al, 1983) to be poorly absorbed from the uterus following intrauterine infusion. O n the basis of such observations, the authors suggested that the intrauterine treatment with OTC and gentamicin may not be adequate in metritis cases.…”

“…were present in effective concentration in the uterine lumen and endometrium for 24, 72 and 6 hours, respectively following intrauterine infusion (GUSTAFSSON, 1980;MASERA et al, 1980 andAL-GUEDAWY et al, 1983).…”

Use of tissue–fluid correlations to estimate gentamicin residues in kidney tissue of Holstein steers

“…As a therapeutic agent, gentamicin remains in effective concentrations in the circulation of the treated patient for only a short time (Al‐Guedawy et al. , 1983; Haddad et al.…”

“…As a therapeutic agent, gentamicin remains in effective concentrations in the circulation of the treated patient for only a short time (Al-Guedawy et al, 1983;Haddad et al, 1986), which is assumed to be related to a rapid and complete elimination of the drug. Greater than 90% of the administered gentamicin is eliminated by the renal route in <2 days (Haddad et al, 1987); however, the small remainder of the drug is bound in the kidney tissue and is removed from this organ at a very slow rate.…”