Is antibiotic treatment efficacious to treat or prevent/control colibacillosis in broiler production? An amendment protocol for a systematic review and meta-analysis.

This protocol is an amendment of the previous study conducted by Sargeant et al. (2019) on the same topic. The description below will mainly focus on modifications provided. This protocol defines the methodology of the systematic review and meta-analysis to address the following PICO question: “In broilers at risk of colibacillosis, does antibiotic treatment versus no antibiotic treatment result in higher FCR/fewer condemnations/lower mortality/total antibiotic use?”. The specific PICO elements are: 1. Population: Broilers (including the whole production chain). 2. Intervention: Any antibiotic licensed for use in chickens in ovo, by injection, in feed, or in water at doses consistent with therapeutic or prophylactic use. Eligible antibiotic include any antibiotic for use in treating or preventing colibacillosis in poultry included in Sargeant et al. (2019) and the OIE list of antibiotic agents of veterinary importance. 3. Comparator: Placebo or untreated control group or an alternative antibiotic treatment. 4. Outcomes: Mortality, Feed Conversion Ratio (FCR), condemnations due to colibacillosis at the slaughterhouse, and total antibiotic use

Are management measures efficacious to prevent or control colibacillosis in broilers production chain? A protocol for a systematic review and meta-analysis.

The protocol is established as an essential and basic tool to perform a systematic review on the efficacy of biosecurity measures to prevent or reduce colibacillosis in broilers

In vitro antibacterial, non-cytotoxic and antioxidant activities of Boscia Senegalensis and Tapinanthus dodoneifolius, plants used by pastoralists in Cameroon

Abstract In the Far North Region of Cameroon, pastoralists use the leaves of Boscia senegalensis and the stem of Tapinanthus dodoneifolius to treat common animal diseases. This study aimed to evaluate the in vitro antibacterial, non-cytotoxic and antioxidant potentials of these plants. To achieve this, four extracts (water, methanol, chloroform and hexane) of both plants obtained by successive fractionation were used. Antibacterial activities of the different extracts were evaluated against three bacterial reference strains including Gram-positive (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli and Salmonella typhi) using agar disc diffusion and broth dilution methods. Human colon cancer cells were used to screen their toxicity. 2,2-Ddiphenyl-1-picrylhydrazyl (DPPH) radical scavenging and ferrous ion chelating assays have been used to investigate the antioxidant activities of the best extract of each plant after antibacterial assay. A sensitive inhibitory effect was observed against S. aureus with hexane extract of B. senegalensis and methanolic extract of T. dodoneifolius. In addition, the results showed that both plant extracts are not toxic. The hexane and methanolic extracts of B. senegalensis and T. dodoneifolius, respectively, showed higher antioxidant activities, but the hexane extract demonstrate a strong hydrogen donating ability or the electron transfer reaction in comparison with vitamin C used as standard. This finding may support the traditional use of both plants for managing animal diseases in the Far North of Cameroon

A systematic review and meta-analysis on the efficacy of vaccination against colibacillosis in broiler production.

Colibacillosis, a disease caused by Escherichia coli in broiler chickens has serious implications on food safety, security, and economic sustainability. Antibiotics are required for treating the disease, while vaccination and biosecurity are used for its prevention. This systematic review and meta-analysis, conducted under the COST Action CA18217-European Network for Optimization of Veterinary Antimicrobial Treatment (ENOVAT), aimed to assess the efficacy of E. coli vaccination in broiler production and provide evidence-based recommendations. A comprehensive search of bibliographic databases, including, PubMed, CAB Abstracts, Web of Science and Agricola, yielded 2,722 articles. Following a defined protocol, 39 studies were selected for data extraction. Most of the studies were experimental infection trials, with only three field studies identified, underscoring the need for more field-based research. The selected studies reported various types of vaccines, including killed (n = 5), subunit (n = 8), outer membrane vesicles/protein-based (n = 4), live/live-attenuated (n = 16), and CpG oligodeoxynucleotides (ODN) (n = 6) vaccines. The risk of bias assessment revealed that a significant proportion of studies reporting mortality (92.3%) or feed conversion ratio (94.8%) as outcomes, had "unclear" regarding bias. The meta-analysis, focused on live-attenuated and CpG ODN vaccines, demonstrated a significant trend favoring both vaccination types in reducing mortality. However, the review also highlighted the challenges in reproducing colibacillosis in experimental setups, due to considerable variation in challenge models involving different routes of infection, predisposing factors, and challenge doses. This highlights the need for standardizing the challenge model to facilitate comparisons between studies and ensure consistent evaluation of vaccine candidates. While progress has been made in the development of E. coli vaccines for broilers, further research is needed to address concerns such as limited heterologous protection, practicability for application, evaluation of efficacy in field conditions and adoption of novel approaches

Antimicrobial usage in Swiss fattening pig farms: is there still potential for improvement?

OBJECTIVE The aim of this study was to analyze antimicrobial usage (AMU) in fattening pig farms that took part in the SuisSano/Safety + Health Programme in Switzerland over the year 2020 and to discuss the potential for further improvement. Usage was examined according to the antimicrobial's class and indication for use, with emphasis on highest priority critically important antimicrobials (HPCIAs). METHODS Data on AMU from 1411 farms, reported in an electronic treatment journal, was used. AMU was quantified through treatment incidence (TI) based on Swiss Defined Daily Doses (DDDch). Indication of use for each antimicrobial class was analyzed with particular focus on HPCIAs. RESULTS The total TI of all antimicrobials used in the farms corresponds to 8.9 DDDch per 1000 pig-days at risk, of which HPCIAs represented 2.6 %. A total of 140 farms (9.9 %) partake in HPCIAs usage, with tylosin (73.8 % of total HPCIA TI) and colistin (22.8 % of total HPCIA TI) being the most frequently antimicrobials used. The most common indication for treatment with HPCIAs was gastrointestinal disorders (62.1 % of total HPCIA TI). CONCLUSION AND CLINICAL RELEVANCE This study shows that the efforts made in recent years to foster prudent use of antimicrobials and, especially HPCIAs in Swiss pig production, have been successful. Indeed, 90.1 % (1271 of 1411) of the farms did not use any HPCIAs over the year 2020. Of the recorded treatments, HPCIA's represented only 2.6 % of the total TIs used in fattening pigs. Since many farms do not use any HPCIAs, knowledge can be obtained from these farms to identify practices which can further reduce or even stop HPCIAs usage. Moreover, information concerning indications for HPCIAs usage provide input concerning where treatment options other than HPCIAs should be explored by both farmers and veterinarians

Unveiling the landscape of resistance against high priority critically important antimicrobials in food-producing animals across Africa: A scoping review.

The rapid population growth in Africa is associated with an increasing demand for livestock products which in turn can lead to antimicrobial use. Antimicrobial usage in animals contributes to the emergence and selection of resistant bacteria which constitutes a serious public health threat. This study aims to review and summarize the available information on highest priority critically important antimicrobials (HPCIAs) resistance in livestock production in Africa. This work will help to inform future policies for controlling antimicrobial resistance (AMR) in the food production chain. A scoping review was conducted according to the Cochrane handbook and following PRISMA 2020 guidelines for reporting. Primary research studies published after 1999 and reporting resistance of Escherichia coli, Enterococcus spp, Staphylococcus aureus, Salmonella spp, and Campylobacter spp to HPCIAs in poultry, cattle, pigs, goats, and sheep in Africa were searched in four databases. A total of 312 articles were included in the review. The majority of the studies (40.7) were conducted in North African countries. More than 49.0% of included studies involved poultry and 26.2% cattle. Cephalosporins and quinolones were the most studied antimicrobial classes. Of the bacteria investigated in the current review, E. coli (41.7%) and Salmonella spp (24.9%) represented the most commonly studied. High levels of resistance against erythromycin in E. coli were found in poultry (MR 96.1%, IQR 83.3-100.0%), cattle (MR 85.7%, IQR 69.2-100.0%), and pigs (MR 94.0%, IQR 86.2-94.0%). In sheep, a high level of resistance was observed in E. coli against nalidixic acid (MR 87.5%, IQR 81.3-93.8%). In goats, the low level of sensibility was noted in S. aureus against streptomycin (MR 86.8%, IQR 19.4-99.0%). The study provides valuable information on HPCIAs resistance in livestock production in Africa and highlights the need for further research and policies to address the public health risk of AMR. This will likely require an investment in diagnostic infrastructure across the continent. Awareness on the harmful impact of AMR in African countries is a requirement to produce more effective and sustainable measures to curb AMR