Efficacy of ceftiofur and flunixin in the early treatment of bronchopneumonia in weaners

Modulation of the Acute Inflammatory Response Induced by the Escherichia coli Lipopolysaccharide through the Interaction of Pentoxifylline and Florfenicol in a Rabbit Model

BACKGROUND

Experimental reports have demonstrated that florfenicol (FFC) exerts potent anti-inflammatory effects, improving survival in a murine endotoxemia model. Considering the anti-inflammatory and immunomodulatory properties of pentoxifylline (PTX) as an adjuvant to enhance the efficacy of antibiotics, the anti-inflammatory effects of the interaction FFC/PTX over the E. coli Lipopolysaccharide (LPS)-induced acute inflammatory response was evaluated in rabbits.

METHODS

Twenty-five clinically healthy New Zealand rabbits (3.8 ± 0.2 kg body weight: bw), were distributed into five experimental groups. Group 1 (control): treated with 1 mL/4 kg bw of 0.9% saline solution (SS) intravenously (IV). Group 2 (LPS): treated with an IV dose of 5 µg/kg of LPS. Group 3 (pentoxifylline (PTX) + LPS): treated with an oral dose of 30 mg/kg PTX, followed by an IV dose of 5 µg/kg of LPS 45 min after PTX. Group 4 (Florfenicol (FFC) + LPS): treated with an IM dose of 20 mg/kg of FFC, followed by an IV dose of 5 µg/kg of LPS 45 min after FFC administration. Group 5 (PTX + FFC + LPS): treated with an oral dose of 30 mg/kg of PTX, followed by an IM dose of 20 mg/kg of FFC, and, 45 min after an IV dose of 5 µg/kg of LPS was administered. The anti-inflammatory response was evaluated through changes in plasma levels of interleukins (TNF-α, IL-1β and IL-6), C-reactive protein (CRP), and body temperature.

RESULTS

It has been shown that each drug produced a partial inhibition over the LPS-induced increase in TNF-α, IL-1β, and CRP. When both drugs were co-administered, a synergistic inhibitory effect on the IL-1β and CRP plasma concentrations was observed, associated with a synergic antipyretic effect. However, the co-administration of PTX/FFC failed to modify the LPS-induced increase in the TNF-α plasma concentrations.

CONCLUSIONS

We concluded that the combination of FFC and PTX in our LPS sepsis models demonstrates immunomodulatory effects. An apparent synergistic effect was observed for the IL-1β inhibition, which peaks at three hours and then decreases. At the same time, each drug alone was superior in reducing TNF-α levels, while the combination was inferior. However, the peak of TNF-α in this sepsis model was at 12 h. Therefore, in rabbits plasma IL-1β and TNF-α could be regulated independently, thus, further research is needed to explore the effects of this combination over a more prolonged period.

Use of non-steroidal anti-inflammatory drugs in porcine health management

OBJECTIVE

Treatment of inflammation and pain management is an important topic in the welfare of pigs. It is very difficult for veterinary practitioners to choose the most appropriate product for a certain problem. This review aims to summarise and discuss the characteristics of different non-steroidal anti-inflammatory drugs (NSAIDs), as well as paracetamol and metamizole, available for pigs in the European Union.

METHODS

The databases Pubmed, Google Scholar, CliniPharm CliniTox and European Medicines Agency were searched. Relevant terms (eg,'meloxicam', 'fever', 'swine', 'pig', 'inflammation', 'castration', 'pain') were used to search for original articles, reviews and books. Only peer-reviewed articles were used. References from studies were also analysed in order to find additional relevant studies.

CONCLUSION

Studies which have investigated the efficacy of NSAIDs for different conditions, using different treatment regimens, are scarce. Most studies focused on the efficacy of NSAID-related pain alleviation in piglet castration, as well as the anti-inflammatory potential of NSAIDs in experimental inflammation models. Little research has been carried out on the use of metamizole, tolfenamic acid, paracetamol and sodium salicylate and their effect in pigs.

Bioequivalence evaluation of two 5% ceftiofur hydrochloride sterile suspension in pigs

The purpose of this study was to evaluate the bioequivalence of 5% ceftiofur hydrochloride sterile suspension in two formulations, a test formulation (Saifukang 5% CEF, Hvsen) and a reference formulation (Excenel^®RTU 5% CEF, Pfizer). Twenty-four healthy pigs were assigned to a two-period, two-treatment crossover parallel trial, and both formulations were administered at a single intramuscular dose of 5 mg/kg weight, with a 7-day washout period. Blood samples were collected consecutively for up to 144 hr after administration. The concentrations of ceftiofur- and desfuroylceftiofur-related metabolites in the plasma were determined by high-performance liquid chromatography. In addition, the major pharmacokinetic parameters (C_max, AUC_0-t and AUC_0-∞) were computed and compared via analysis of variance, with 90% confidence intervals. Bioequivalence evaluation of T_max was statistically analyzed with the nonparametric test. The comparison values between test and reference formulation for AUC_0-t, AUC_0-∞, C_max, and T_max were 376.7 ± 75.3 µg·hr/ml, 390.5 ± 78.6 µg·hr/ml, 385.9 ± 79.2 µg·hr/ml, 402.7 ± 80.4 µg·hr/ml, 34.6 ± 5.5 µg/ml, 36.1 ± 6.2 µg/ml, 1.27 ± 0.18 hr, and 1.26 ± 0.21 hr, respectively, and we observed no significant differences between the two formulations. The 90% CI values were within the recommended range of 80–125% (P>0.05), and the relative bioavailability of the test product was 96.47 ± 10.92% according to AUC_0-t values. Based on our results, the two formulations exhibit comparable pharmacokinetic profiles, and the test product is bioequivalent to the reference formulation.

Ceftiofur attenuates lipopolysaccharide-induced acute lung injury

Ceftiofur is a new broad-spectrum, third-generation cephalosporin antibiotic for veterinary use. Our laboratory has previously been reported that ceftiofur can modulate early cytokine responses and increase mouse survival in endotoxemia. In the present study, we investigated the effect of ceftiofur on acute lung injury (ALI) induced by lipopolysaccharide (LPS) in vivo. Mice were pretreated with ceftiofur 1h before challenge with a dose of 0.5mg/kg LPS. Mice treated with LPS alone showed marked increased TNF-alpha, IL-6, and IL-8 levels in the bronchoalveolar lavage fluid (BALF). When pretreated with 30mg/kg of ceftiofur, the TNF-alpha, IL-6, and IL-8 levels were significantly decreased. In addition, the W/D ratio of the lung tissue and the number of total cells, neutrophils and macrophages in the BALF significantly decreased at 8h after pretreatment with ceftiofur. Furthermore, ceftiofur markedly attenuated the LPS-induced histological alteration. These studies indicate that ceftiofur significantly decreases the inflammation in a murine model of LPS-mediated ALI and may represent a novel prevention strategy for nonspecific inflammation in the lungs.

Pharmacokinetics of ceftiofur hydrochloride in pigs infected with porcine reproductive and respiratory syndrome virus

OBJECTIVES

To compare the pharmacokinetic profile of ceftiofur hydrochloride (ceftiofur) administered intramuscularly at 3 mg/kg body weight (BW) in pigs infected with porcine reproductive and respiratory syndrome virus (PRRSV) versus clinically healthy pigs.

METHODS

Sixteen 3- to 4-week-old PRRSV-negative pigs were randomly assigned to two groups (A and B), with eight pigs per group. Pigs in Group A were uninfected controls and pigs in Group B were intranasally challenged with a PRRSV isolate of Thai origin. Pigs in both groups were intramuscularly administered ceftiofur at 3 mg/kg BW at 7 days post-infection. Blood samples were serially collected up to 72 h post-injection. Plasma was analysed for ceftiofur and its related metabolites using HPLC. Pharmacokinetic parameters of ceftiofur were calculated based on non-compartmental analysis.

RESULTS

Pharmacokinetic parameters of ceftiofur revealed statistically significant differences (P < 0.01) in maximum concentration (C(max)), AUC, volume of distribution at the terminal phase over bioavailability (V(z)/F), clearance over bioavailability (CL/F) and the terminal half-life (t(1/2z)) between Groups A and B. PRRSV-infected pigs had a V(z)/F and CL/F of ceftiofur significantly higher than in the non-infected pigs (116% increase in V(z)/F, 234% increase in CL/F). The C(max) and AUC of the infected pigs decreased by 54% and 70%, respectively, compared with the non-infected pigs. The t(1/2z) of the infected pigs and the non-infected pigs was 13.1 and 21.0 h, respectively.

CONCLUSIONS

The pharmacokinetic profile of ceftiofur is altered in PRRSV-infected pigs due to the decreased plasma ceftiofur concentration compared with clinically healthy pigs.