Evaluation of the effectiveness of intrauterine treatment with formosulphathiazole of clinical endometritis in postpartum dairy cows.

In cattle, elimination of bacterial contamination from the uterine lumen after parturition is often delayed or compromised, and pathogenic bacteria can persist, causing uterine disease and infertility. The aim of this study was to compare the clinical and bacteriologic recovery following a single intrauterine administration of formosulphatiazole, cephapirin or placebo in cows with clinical endometritis. Cows (n = 80), no less than 28 days postpartum, with clinical endometritis were enrolled in the study. Endometritis was diagnosed by a complete reproductive examination, including rectal palpation, ultrasonography, vaginoscopy and uterine swab. All cows were randomly assigned to receive one of three intrauterine treatments (T0): 2500 mg of formosulphatiazole (Group A); 500 mg of cephapirin (Group B); placebo (4250 mg of propylene glycol; Group C). Cows were examined at the first estrus after treatment or no more than 30 days after (T1). Bacteria isolated were E. coli, A. pyogenes, Pasteurella spp. and Streptococcus spp. After treatment, in Group A and B only 6/30 (20.0%) and 6/24 (25.0%) cows showed a positive bacteriologic culture (P > 0.05), while in Group C the number of positive animals was significantly higher (19/26; 73.1%; P < 0.05). At T0, total clinical scores were similar between the three groups (Group A: 5.84 ± 1.07; Group B: 5.91 ± 1.0; Group C: 5.62 ± 1.17; P > 0.05) and indicative of clinical endometritis. At T1, endometritis scores were significantly lower than those reported before uterine infusion (P < 0.05); however, Group A and B score, 0.4 ± 0.9 and 1.0 ± 2.1, respectively, correspond to no and slight endometritis, while animals in Group C reported a total endometritis score significantly higher (4.6 ± 3.5; P < 0.05) corresponding to endometritis. In the present study, a commercial formosulphatiazole preparation was as effective as cephapirin and more effective than placebo for the treatment of clinical endometritis.

Preliminary evidence of the contribution of the intestinal microflora to biotin supply in zebrafish Danio rerio (Hamilton-Buchanan).

A study was conducted to preliminarily assess the contribution of the intestinal microflora to biotin supply in zebrafish. Biotin and avidin were added to three isonitrogenous and isocaloric purified diets to provide molar avidin: biotin ratios of 0:0 (basal diet), 0:1 (biotin-supplemented diet), and 120:0. Another diet was made by supplementing the antibiotic succinylsulfathiazole (1%, wt/wt) to the basal diet. A fifth diet was the Zeigler commercial diet for zebrafish. Each diet was fed to a triplicate group of fish (mean initial mass 0.266 g) for 8 weeks. The condition factor, feed conversion ratio (FCR), percentage weight gain, and survival were similar in fish groups fed the commercial and the biotin-supplemented diets, but energy conversion efficiency and whole-body biotin content were highest in the fish fed the commercial diet (p<0.05). Reduced growth and survival, and increased FCR were noted in fish fed basal diet compared with those fed biotin-supplemented diet. The supplementation of avidin in diet led to lower survival and condition factor, and higher FCR than that observed with basal diet. Intestinal microbial synthesis is assumed to be a significant source of biotin to the zebrafish, as fish fed the antibiotic-supplemented diet showed the lowest growth, health condition, and feed utilization.

Manipulating hydrate formation during high shear wet granulation using polymeric excipients.

Active pharmaceutical ingredients (API) can undergo an anhydrate to hydrate transformation during wet granulation and this transformation may either result in mixed crystalline forms or an unwanted form in the final drug product. Previous studies have shown that it may be possible to inhibit this transformation with polymeric excipients. In this study, three model compounds, caffeine (CAF), carbamazepine (CBZ), and sulfaguanidine (SGN), were subjected to high shear wet granulation and phase transformations were monitored using in-line Raman spectroscopy. Wet granulation was performed in the presence and absence of various polymeric excipients to determine the extent of the inhibitory effects. Although several polymers had some retardation effect, cross-linked poly(acrylic) acid was found to completely inhibit the CAF transformation and both hydroxypropyl methylcellulose and cross-linked poly(acrylic) acid completely inhibited the CBZ transformation. For SGN, transformation to the hydrate was rapid, even in the presence of the polymers. The observed inhibitory effects were attributed to either specific interactions between the polymer and the API crystal or substantial water absorption by the polymer. There was also evidence from physical property testing that the inclusion of a small amount of inhibitory polymer did not significantly change the compaction or flow behavior of the final granulation.

Polymorph farming of acetaminophen and sulfathiazole on a chip.

PURPOSE: The aim of this paper is to understand at a given temperature (1) the role of template films, the droplet volume of a saturated sulfathiazole aqueous solution and the solvent on polymorph screening of sulfathiazole on a silicon wafer, and (2) the effect of template films on the acetaminophen crystal face at the template-crystal interface. MATERIALS AND METHODS: Template Effect: Spun cast template films of non-annealed chitosan and annealed chitosan at 140 degrees C on silicon wafers were prepared. A 0.01-cm(3) saturated sulfathiazole aqueous solution droplets were deposited on both kinds of chitosan film. Sulfathiazole crystals were produced on those films by evaporation at 25 degrees C. Volume Effect: Different droplet volumes of a saturated sulfathiazole aqueous solution ranging from 0.01 to 0.14 to 2.7 cm(3) were deposited on non-annealed chitosan films. Sulfathiazole crystals were generated on those films by evaporation at 25 degrees C. Solvent Effect: 0.01 cm(3) saturated sulfathiazole methanol solution droplets were deposited on non-annealed chitosan films and sulfathiazole crystals were formed on those films by evaporation at 25 degrees C. The formation pathways of different sulfathiazole crystal polymorphs of the above mentioned effects were analyzed and verified by systematic studies. Template-crystal Interfacial Study: Millimeter-sized acetaminophen crystals were successfully grown on non-annealed chlorosulfonated poly(ethylene) (PE-Chl) and chitosan template films by cooling the saturated acetaminophen aqueous solution from 50 to 25 degrees C in which those template films were immersed. The bonding energies for specific carbons collected by electron spectroscopy for chemical analysis (ESCA) at the acetaminophen crystal surface, together with the molecular interactions between acetaminophen and PE-Chl and between acetaminophen and chitosan in separately prepared solid dispersion film samples detected by Fourier transformed infrared (FTIR) spectroscopy, proved to be useful for identifying the crystal face of acetaminophen essential for its specific intermolecular interactions at the template-crystal interface. RESULTS: Thermodynamically metastable sulfathiazole Form I crystals were reproducibly obtained on the non-annealed chitosan films whereas the stable sulfathiazole Form III crystals were repeatedly formed on the annealed chitosan films. Droplet volumes and solvents were also found responsible for the polymorphic outcome of sulfathiazole in the kinetically driven area of two overlapping metastable zones from two competing polymorphs of Form I and Form III. Thermodynamically stable sulfathiazole Form III crystals were formed on the non-annealed chitosan films instead when the droplet volumes of a saturated sulfathiazole aqueous solution were increased from 0.01 to 0.14 cm(3) and 2.7 cm(3). When the solvent was changed from water to methanol, the thermodynamically stable sulfathiazole Form III crystals were again observed on the non-annealed chitosan films even from the 0.01 cm(3) saturated sulfathiazole methanol solution droplets. CONCLUSIONS: Template surfaces were thought to provide specific functional groups to either change the energy barrier for the nuclei formation of the thermodynamically metastable Form I or alter the droplet contact angle and the droplet surface area which was related to the droplet evaporation time. The evaporation time determines the amount of time available for the polymorphic transformation from Form I to Form III. Apparently, droplet volumes could also determine the amount of time needed to reach supersaturation and the amount of time available for a polymorphic transformation from Form I to Form III. In addition, the molecular conformation and viscosity of solvents such as methanol might alter the original nucleation kinetics in water and lead to a more rapid polymorphic transformation from Form I to Form III. Template films of PE-Chl and chitosan were found to be critical for determining the face of a millimeter-sized acetaminophen crystal at the template-crystal interface. The idea of performing polymorph screening on the template film deposited on a chip has opened up a new doorway to examine the roles of: (1) various kinds of drug carrier in the form of a template film, (2) the droplet volume of a saturated solution, and (3) the type of solvent used, in polymorphic control. Growing millimeter-sized crystals directly on the chip of template has also provided a convenient technology enabling platform for examining the crystal-template interface by solid-state characterization techniques such as ESCA.

Serum activity/concentration profiles of a sustained-released formulation of sulphathiazole-trimethoprim (2.5:1) in calves.

Thirty-six two-week-old healthy Holstein-Friesian calves weighing between 52 and 58 kg were divided at random into three groups of 12; group A calves were given a single oral bolus containing 2.5 g sulphathiazole and 1 g trimethoprim in a sustained-release formulation; group B received the same doses of the drugs but the trimethoprim was not in a sustained-release formulation; group C received a bolus containing 2.5 g sulphathiazole and 0.5 g conventional trimethoprim. Blood samples were collected at intervals for two days, the serum was separated and the composite antibacterial activity profiles of the mixture were analysed by an agar-diffusion microbiological method. The mean maximum activities in the serum of the three groups were 23.4 microg/ml in group A, 9.25 microg/ml in group B and 8.01 microg/ml in group C. The mean areas under the curves of the serum activity time curves were 838 microg/ml/hour in group A, 216 microg/ml/hour in group B and 182 microg/ml/hour in group C.

Metabolic fate of orally administered phyllodulcin in rats.

Naturally occurring phyllodulcin (1) was orally administered to rats to investigate its metabolic fate. Urinary metabolites were analyzed by three-dimensional HPLC. Phyllodulcin-3'-O-sulfate (2), phyllodulcin-3'-O-beta-glucuronide (3), 2-[2-(3,4-dihydroxyphenyl)ethyl]-6-hydroxybenzoic acid (4), and one novel bibenzyl derivative, 2-[2-(3-hydroxy-4-methoxyphenyl)ethyl]-6-hydroxybenzoic acid (5), together with thunberginol G (6) and hydrangenol (7) were isolated from the phyllodulcin-treated urine. 1 was extensively metabolized to 4-6 by a rat fecal suspension after incubation for 24 h. Urinary excretion of 4-6 in rats administered phyllodulcin orally was substantially reduced when the rats were treated with antibiotics to suppress their intestinal flora. On the other hand, the incubation of 1 with rat liver S-9 mix showed the presence of 7 together with 4 and 5.

Determination of sulfathiazole in type C medicated swine feed by reversed-phase liquid chromatography with post-column derivatization.

A convenient method was developed for determination of sulfathiazole (STZ) in Type C medicated swine feed by reversed-phase liquid chromatography (LC) with post-column derivatization. Addition of extractant solution (0.2N HCl and 1.5% diethylamine in 25% methanol) and an internal standard (IS), sulfamethylthiazole (SMZ), to 5 g sample was followed by mechanical shaking for 1 h. The extract was clarified by chilling, centrifugation, and filtering before injection onto a C18 reversed-phase column. The mobile phase components were 2% acetic acid and 1:1 acetonitrile-methanol (83 + 17%, v/v). Run time was about 20 min. Determination and, largely, the method's selectivity were based on detection at 450 nm of the derivative formed by the post-column reaction of dimethylaminobenzaldehyde with the primary amine of the analyte and IS. The IS, SMZ, differs from STZ by a single substituent methyl group, is stable, and is readily resolved from STZ. Although SMZ is not commercially available, it can be synthesized with relative ease from purchased reagents and will be supplied by the authors to interested laboratories. In single-laboratory validation, linearity was demonstrated over the range of 0.055-550 microg/mL, well beyond the target concentration of 5.5 microg/mL. The estimated limit of detection was 0.04 microg/mL; the calculated limit of quantitation was 0.13 microg/mL (feed concentration of 2.4 g/T or 2.7 mg/kg). Wet-spiking trials with a variety of swine feed matrixes showed recovery to be 100-102% for the intended concentration range, 50-200 g/T, with coefficient of variation (CV) < 2%. The method ruggedness was verified with an overall CV of 2.9%.

Release characteristics of pectin microspheres prepared by an emulsification technique.

The potential application of pectin as a matrix polymer for making microspheres by an emulsification technique was explored, and the drug release property of these pectinate microspheres containing drug cores of varying aqueous solubilities: sulphanilamide, sulphaguanidine and sulphathiazole, was investigated using different dissolution media. The size and size distribution, specific surface area, drug content and drug release property of the pectinate microspheres were determined. The solubility and solution pH of drugs and their propensity to interact with pectin were characterized. Pectinate microspheres were successfully prepared by external gelation, using a modified emulsification technique. The kinetics of drug release from the microspheres best fitted Higuchi's model. Interestingly, the lowest percentage of drug released was produced by microspheres which were smallest in size and, therefore, largest in specific surface area, and containing sulphanilamide, the most aqueous soluble and the lowest molecular weight drug. Mathematical correlation study indicated that the drug release profile of pectinate microspheres was notably affected by the drug content and the extent of drug-pectin interaction in the microspheres. Generally, a higher percentage of drug was released from the microspheres with a higher drug content and/or lower extent of drug-pectin interaction. The extent of drug-pectin interaction was highest in microspheres containing sulphanilamide, followed by sulphaguanidine and sulphathiazole, opposite to that of drug content.

Quantifying crystalline form composition in binary powder mixtures using near-infrared reflectance spectroscopy.

The objectives of this study were to assess the utility of near-infrared reflectance spectroscopy (NIRS) in differentiating crystalline forms of pharmaceutical materials and determine the accuracy of this technique in quantifying crystalline forms of solids in binary mixtures. Various crystalline forms of sulfamethoxazole, sulfathiazole, lactose, and ampicillin, independently characterized with other methods, were analyzed qualitatively and quantitatively. The observed differences in near-infrared (NIR) spectra of crystalline form pairs were interpretable on the basis of the features of their crystalline and molecular structures and mid-infrared spectra. NIR spectra of binary physical mixtures of crystalline form pairs were obtained directly through glass vials over the wavelength range of 1100-2500 nm. The calibration lines were constructed using an inverted least-squares regression method. The ratio of the response of the second derivative of the reflectance spectra at two wavelengths was plotted versus crystal form composition. The correlation coefficients for plots of predicted versus theoretical composition were generally greater than 0.99 and standard errors were all low. Parallel studies comparing the NIRS method to a quantitative x-ray powder diffraction method using sulfamethoxazole and sulfathiazole confirmed the accuracy of the results. Additional NIRS studies were conducted in the 0-10% composition range with ampicillin and sulfamethoxazole. These results indicated that prediction down to the 1% level was possible. This study demonstrates that NIRS can be used as a quantitative physical characterization method, is comparable in accuracy to other techniques, and is capable of detecting low levels of one crystal form in the presence of another.

[The effect of ftalazol on the body allowance in rats of B-group vitamins]. / Vliianie ftalazola na obespechennost' organizma krys nekotorymi vitaminami gruppy B.

A certain decrease in the content of riboflavin in blood plasma and liver and its excretion in the urine were encountered 24-h after administration of phthalazol, according to the schedule of acute dysentery treatment, in rats with initial moderate deficiency in vitamins B1 and B2. The provision with vitamin B1 did not change in this case. The introduction of phthalazol was attended with a noticeable decrease in the excretion of pyridoxic acid but did not affect the B6 content in the liver and blood serum of the animals.

Polyphosphazene membranes and microspheres in periodontal diseases and implant surgery.

Membranes or microcapsules made from polyphosphazenes bearing amino acid side groups are proposed for the treatment of periodontal diseases. Polyphosphazene membranes, prepared with alanine ethyl ester and imidazole in the molar ratio of 80:20 as phosphorus substituents, gave a degradation rate that corresponded to the healing of the bone defect. These membranes were much more successful in promoting healing of rabbit tibia defects than polytetrafluoroethylene membranes. Antibacterial or anti-inflammatory drugs, useful in periodontal tissue regeneration, could be entrapped in the polyphosphazene membranes and released both in vitro and in vivo at a rate that ensured therapeutic concentrations in the surrounding tissue. Polyphosphazene microspheres, prepared with phenylalanine ethyl ester as a phosphorus substituent and loaded with succinylsulphathiazole or naproxen, were also obtained. The kinetics of release from these matrices were very convenient in yielding local concentrations of the two drugs that are useful per se or when mixed with hydroxyapatite for better bone formation.

[Studies on the antiviral activity of silver sulfathiazole]. / Badania przeciwwirusowej aktywnosci soli srebrowej sulfatiazolu.

Silver sulfathiazole shows strong antibacterial activity and good tolerance after topical application. The aim of the study was to determine the antiviral activity of silver sulfathiazole in tissue culture after incubation of drug and virus. The antiviral activity was measured after various periods of exposure and at different drug concentrations. The results obtained indicate the activity of silver sulfathiazole against Herpesvirus type 1 and type 2. This drug suppresses or completely inactivates the infectivity of virus. The antiviral effect is directly related to concentration of the drug and duration of exposure. At concentration of 10 micrograms/ml it has the highest activity after 30 minutes of exposure, however at a concentration of 20 micrograms/ml it induces a similar effect after 10 minutes. Silver sulfathiazole had antiviral activity similar to that of silver nitrate, while sulfathiazole alone was ineffective.

Effects of drug solubility, drug loading, and polymer molecular weight on drug release from Polyox tablets.

This study investigated the effects of polymer molecular weight, drug solubility, addition of a water-soluble excipient, and drug loading on zero-order release kinetics and elucidated the release mechanism of a drug from directly compressed tablets. Directly compressed tablets consisting of polyethylene oxides (PEO) (MW = 0.9, 2.0 and 4.0 x 10(6)) and drugs (solubility ranging from 290 to 25,000 mg/l) were formulated with or without a water-soluble excipient (lactose). For PEO tablets (MW = 0.9 x 10(6)), drug release is primarily swelling/erosion controlled for drugs for which solubility is below 1%, resulting in zero-order release kinetics. For PEO tablets (MW = 4.0 x 10(6)), drug release is controlled at a zero-order rate by the dissolution rate of the drug at high loading (39%). At low loading (20%), drug diffusion through the swollen gel layer becomes the governing release mechanism. For a highly water-soluble drug (e.g., diclofenac Na), drug diffusion is the controlling mechanism regardless of the molecular weight of the PEOs. Zero-order release kinetics can be achieved with PEO tablets (MW = 0.9 x 10(6)) for drugs for which solubility is below 1%. PEO tablets (MW = 2.0 x 10(6)) provided zero-order release for poorly water-soluble drugs (below 0.2%) at 39% drug loading. It is possible to attain zero-order release kinetics with PEO tablets (MW = 4.0 x 10(6)) using a drug which has a solubility of less than 0.1%.

Water-soluble polycations as oral drug carriers (tablets).

New bioerodible materials that are noncross-linked and water-soluble copolymers of trimethylaminoethyl methacrylate chloride (TMAEMC) and methyl methacrylate (MMA) were synthesized and then bound to anionic drugs (diclofenac Na and Na sulfathiazote) to form water-insoluble complexes. These drug-polymer complexes release the bound drugs only in ionic media. Compressed tablets were prepared from these anion-exchange resins, and their release profiles follow zero-order kinetics (n > 0.89, where n is the release exponent). The effects of various excipients (dextrose, lactose, and microcrystalline cellulose) were studied, and the polymer composition was found to influence the duration of drug release. It was also found that the release of anionic drugs from drug-PTMAEM/MMA is linear and that it is possible to "tailor-make" their release kinetics by suitably altering the copolymer composition. When a high content of a water-insoluble excipient (i.e., microcrystalline cellulose) was used to fabricate the tablets, the release kinetics deviated from linearity (n = 0.73). In general, release kinetics were well described by a dissociation/erosion mechanism. Drug loading could be increased by increasing the exchange capacity of the polymer (i.e., by increasing the content of the quaternary amine monomer).

Deposition kinetics, metabolism and urinary excretion of sulfathiazole following oral administration in sheep.

Deposition kinetics, metabolism and urinary excretion of sulfathiazole were investigated in German black head sheep following single oral administration (100 mg/kg). Kinetic evaluation of plasma levels was performed using a two-compartment best fit model. Sulfathiazole is significantly metabolized to N4-acetyl metabolite in the rumen fluid. The drug is very poorly absorbed since the minimum effective concentration in plasma was not attained at any time following oral administration. The prolonged elimination half-life in sheep may be due to a low rate of drug absorption from the rumen and gastro-intestinal tract. Sulfathiazole was mainly excreted in the urine as free drug and N4-acetyl metabolite.

Deviation of the ratio of drugs in a two-component mixture encapsulated in cellulose phthalate microspheres.

Microspheres were formed when a solution of cellulose phthalate was extruded into 30% glacial acetic acid solution. Sulphonamides entrapped in such microspheres leached into the hardening solution because they dissolved freely in the acetic acid solution. This resulted in poor loading efficiency of the sulphonamides in the microspheres. When mixtures of sulphaguanidine and sulphathiazole in various drug ratios were microencapsulated by this method, the observed drug ratios were found to be markedly changed. This was attributed to the difference in solubility of the two sulphonamides in acid such that their extent of diffusion into the hardening solution was not similar. NSAIDS such as ibuprofen and mefenamic acid which are acidic and more hydrophobic in nature are less soluble in acetic acid. These drugs were retained better in the microspheres during the hardening process and the loading efficiency was consequently improved. In cases where mixture of the NSAIDS were encapsulated, the drug ratios showed little deviation from the theoretical values. This study shows that loading of the CAP microspheres is dependent on the solubility of the drugs in acetic acid. When more than one drug is required to be microencapsulated, the drug ratio may change if the drugs have different solubility in acetic acid.

In vitro metabolism of sulfathiazole in rumen fluid and its metabolism and disposition kinetics following intraruminal administration in sheep.

The antimicrobial agents may undergo a change in the complex stomach particularly in the rumen as a result of microbial fermentation in ruminants. Present investigation deals with the influence of ruminal fluid probably the role of ruminal microorganisms on the degradation of sulfathiazole in vitro and its metabolism and disposition following its single intraruminal administration (100 mg/kg) in adult german black head sheep. Sulfathiazole is metabolized to N4-acetyl sulfathiazole in the rumen fluid after its in vitro incubation at different concentrations (10-60 micrograms/ml) for varying time intervals (1-6 h) at a temperature of 38 +/- 0.5 degrees C. Likewise in vivo it is significantly metabolized to its N-acetyl metabolite in the rumen after an intraruminal administration. The levels of sulfathiazole are maintained above minimum effective therapeutic concentration (40 micrograms/ml) for more than 24 h in rumen fluid. The drug is poorly absorbed into the circulation after intraruminal administration since the levels in plasma could not reach up to minimum effective therapeutic concentration at any time. The biological half-life of sulfathiazole was found to be 16.7 h following single intraruminal administration. Results of this investigation suggest that oral or intraruminal application of sulfathiazole has only local effects in the rumen fluid. A systemic treatment is not possible after this path of application.

Oral bioavailability of sulphamethoxydiazine, sulphathiazole and sulphamoxole in dwarf goats.

To get a better insight into the oral bioavailability of sulphonamides in ruminants, sulphamethoxydiazine (pKa 7.0), sulphathiazole (pKa 7.2), and sulphamoxole (pKa 7.4) were administered to dwarf goats (n = 5). The drugs were given at 2-week intervals by the intravenous or intraruminal route at a dose of 100 mg per kg body weight. After IV injection, the mean half-life (t1/2 beta in h +/- SEM) was 0.80 +/- 0.10 h, 2.35 +/- 0.38 h, and 3.36 +/- 1.25 h, for sulphathiazole, sulphamoxole, and sulphamethoxydiazine, respectively and the mean distribution volume (Vd beta) was 0.23 +/- 0.05 l/kg, 0.23 +/- 0.04 l/kg, and 0.33 +/- 0.02 l/kg. After intraruminal administration, the mean bioavailability varied from 86.0 +/- 11.8% for sulphamethoxydiazine to 46.6 +/- 4.3% for sulphamoxole, and 52.6 +/- 7.2% for sulphathiazole. The elimination half-life was significantly prolonged, probably due to a low rate of drug absorption from the gastrointestinal tract. In contrast to chloramphenicol, the sulphonamides studied were stable when incubated in rumen fluid at 39 degrees C.

[The effect of food medication alone or in combination with PGF2 alpha on the reproductive performance of swine with SUGD (swine urogenital disease)]. / Der Einfluss einer Futtermedizinierung allein oder in Kombination mit PGF2 alpha auf die Reproduktionsleistung bei Schweinen mit SUGD (swine urogenital disease).

In a large pig production unit 60 postparturient sows were divided at random into 3 groups, each with 20 sows. Group 1 (20 sows) received 30 g Farmavet Trisulfa per os daily from the beginning of the postfarrowing period for 1 week. Group 2 (20 sows) received 30 g Farmavet Trisulfa per os daily from the beginning of the postfarrowing period for 1 week, and in addition were given 3 mg Gabbrostim 24-48 hours after farrowing in a single i.m. application. Group 3 (20 sows) untreated control. The following parameters were evaluated: A: number of weaned piglets per sow, B: weaning to service interval in days, C: return to oestrus in percent. Both groups 1 and 2 showed better results when compared to the control group. Group 2 was superior to group 1.

Effect of Haemonchus contortus infection on the clearance of antipyrine, sulfobromophthalein, chloramphenicol, and sulfathiazole in lambs.

A study was made to determine the effect of Haemonchus contortus parasitic infection in lambs on the clearance of several IV administered drugs. Clearance of sulfobromophthalein or sulfathiazole from the plasma of lambs was unaffected by infection with H contortus. Clearance of antipyrine was enhanced by the infection, and thiabendazole treatment did not alter this effect. Clearance of chloramphenicol (CAP), administered as the succinate ester (CAPS), was not changed by the infection, but it was increased after treatment with thiabendazole. Changes in the mean body residence time and initial plasma concentration of CAPS and CAP after treatment with thiabendazole indicate that hydrolysis of CAPS to CAP was reduced. High concentrations of CAPS apparently enhanced its own elimination directly rather than via the expected sequence involving hydrolysis, glucuronidation, and excretion of CAP-glucuronide. Enhanced clearance of antipyrine following infection of lambs with H contortus can be explained in at least 2 ways. First, it is possible that the lambs did not have mature amounts of hepatic drug metabolizing enzyme activity as reported by other investigators, which may be explained by breed differences or animal husbandry practices. Second, infection of lambs by H contortus may have triggered an inductive response in hepatic cytochrome P-450-mediated activities, which might result via a generalized enhancement in hepatic protein synthesis associated with the physiologic response to replace plasma proteins and other blood components lost through gastrointestinal hemorrhage caused by the active feeding of adult worms. Other phase-II reactions such as acetylation, glucuronidation, and glutathione-S-transferase apparently were not affected.