A cross-sectional study was conducted to assess antibiotic usage, residues, resistance and drivers of their emergence in fish aquaculture in Northern Nigeria between 2019 and 2020. A structured questionnaire was administered to 151 randomly selected farmers. Fish, column and wastewater samples were analysed with enzyme link immunosorbent assay (ELISA) for residue detection and quantification. We performed descriptive and analytic statistical analyses. All selected farmers participated, 78.1% used antibiotics in ponds. Majority (77.1%) of the farmers did not know what antibiotic misuse entailed and 73.3% mentioned that antibiotic misuse and overuse cannot predispose to residues and resistance. The most frequently used antibiotics were tetracyclines (TCs) (99.2%). Significant risk routes for residue and resistance spread were: contaminated fish and its products ingestion, direct contact with fish and fomites contaminated as well as water and aerosols contaminated in the pond environment. Significant social and cultural that influenced residue and resistance development include antibiotics misuse/overuse (Odds Ratio [OR] = 3.8; 95% confidence interval [CI]: 1.62–8.74) as well as poor education and expertise of the farmers (OR = 2.9; 95% CI: 1.24–6.94). The mean TCs residues level in column and wastewater was 123.6 ± 18.2 μg/kg−1. Poor knowledge and attitudes regarding antibiotic usage were identified. Adequate antibiotic stewardship should be promoted through farmers’ education. Identified social and cultural factors can be mitigated through the ‘One Health’ approach.

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Various zoonotic microorganisms cause reproductive problems such as abortions and stillbirths, leading to economic losses on farms, particularly within livestock. In South Africa, bovine brucellosis is endemic in cattle, and from 2013–2018, outbreaks of Brucella melitensis occurred in sable. Coxiella burnetii, the agent responsible for the zoonotic disease known as Q-fever and/or coxiellosis, also causes reproductive problems and infects multiple domestic animal species worldwide, including humans. However, little is known of this disease in wildlife. With the expansion of the wildlife industry in South Africa, diseases like brucellosis and coxiellosis can significantly impact herd breeding success because of challenges in identifying, managing and treating diseases in wildlife populations. This study investigated samples obtained from aborted sable and roan antelope, initially suspected to be brucellosis, from game farms in South Africa using serology tests and ruminant VetMAX™ polymerase chain reaction (PCR) abortion kit. The presence of C. burnetii was confirmed with PCR in a sable abortion case, while samples from both sable and roan were seropositive for C. burnetii indirect enzyme-linked immunosorbent assay (iELISA). This study represents the initial report of C. burnetii infection in sable and roan antelope in South Africa. Epidemiological investigations are crucial to assess the risk of C. burnetii in sable and roan populations, as well as wildlife and livestock in general, across South Africa. This is important in intensive farming practices, particularly as Q-fever, being a zoonotic disease, poses a particular threat to the health of veterinarians and farm workers as well as domestic animals. Contribution: A report of clinical C. burnetii infection in the wildlife industry contributes towards the limited knowledge of this zoonotic disease in South Africa.

Rabies is endemic in Sudan with continuing outbreaks occurring annually, the most common animals affected are dogs, followed by goats and equids. This work focused on equid rabies, to elucidate the current situation of the disease through analysis of reports of equid rabies outbreaks in Sudan during 2010–2022 supported by laboratory confirmation of the disease. During the study period, 66 animals were affected during 35 equid rabies outbreaks. The highest incidences were found in Al Gezira (30.3%), followed by Darfur (24.2%) and Kordofan (15.2%). The highest incidence rate was observed during 2018 (33.3%), followed by 2015 (16.7%). Within seasons, the highest incidence rate was reported during October – December (33.3%), followed by July – September (30.3%). Chi-square analysis revealed a significant correlation between rabid animals and year, season, and state. Wald statistics demonstrated that year and season had a significant association with the disease. Virus antigen was identified (72.2%) in brain tissues using the fluorescent antibody test. Viral nucleic acid was amplified (n = 6) with a reverse transcriptase polymerase chain reaction assay. Contribution: As equids are kept in close contact with humans and other animals in the country, according to the present investigation, equid rabies in Sudan is a potential public health concern, emphasising the importance of implementing effective control measures.

Newcastle disease (ND) is endemic in Angola. Several outbreaks of ND occurred in small backyard flocks and village chickens with high mortality in the southern provinces of the country, Cunene, Namibe and Huíla, in 2016 and 2018. In those years, 15 virulent ND virus (NDV) strains were isolated and grouped within subgenotype 2 of genotype VII (subgenotype VII.2). We now present a study on the thermostability of the isolates, aiming at the selection of the most thermostable strains that, after being genetically modified to reduce their virulence, can be adapted to the production of vaccines less dependent on cold chain and more adequate to protect native chickens against ND. Heat-inactivation kinetics of haemagglutinin (Ha) activity and infectivity (I) of the isolates were determined by incubating aliquots of virus at 56 °C for different time intervals. The two isolates from Namibe province showed a decrease in infectivity of 2 log10 in ≤ 10 min, therefore belonging to the I-phenotype, but while the NB1 isolate from 2016 maintained the Ha activity up to 30 min and was classified as thermostable virus (I−Ha+), the Ha activity of the 2018 NB2 isolate decreased by 2 log2 in 30 min, being classified as a thermolabile virus (I−Ha−). Of the 13 NDV isolates from Huíla province, 10 isolates were classified as thermostable, eight with phenotype I+Ha+ and 2 with phenotype I−Ha+. The other three isolates from this province were classified as thermolabile viruses (I−Ha−). Contribution: This study will contribute to the control and/or eradication of Newcastle disease virus in Angola. The thermostable viral strains isolated from chickens in the country can be genetically manipulated by reverse genetic technology in order to reduce their virulence and use them as a vaccine in the remote areas of Angola.

Global aflatoxin contamination of agricultural commodities is of the most concern in food safety and quality. This study investigated the hepatoprotective effect of 80% methanolic leaf extract of Annona senegalensis against aflatoxin B1 (AFB1)-induced toxicity in rats. A. senegalensis has shown to inhibit genotoxicity of aflatoxin B1 in vitro. The rats were divided into six groups including untreated control, aflatoxin B1 only (negative control); curcumin (positive control; 10 mg/kg); and three groups receiving different doses (100 mg/kg, 200 mg/kg, and 300 mg/kg) of A. senegalensis extract. The rats received treatment (with the exception of untreated group) for 7 days prior to intoxication with aflatoxin B1. Serum levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, and creatinine were measured. Hepatic tissues were analysed for histological alterations. Administration of A. senegalensis extract demonstrated hepatoprotective effects against aflatoxin B1-induced toxicity in vivo by significantly reducing the level of serum aspartate aminotransferase and alanine aminotransferase and regenerating the hepatocytes. No significant changes were observed in the levels of alkaline phosphatase, lactate dehydrogenase, and creatinine for the AFB1 intoxicated group, curcumin+AFB1 and Annona senegalensis leaf extract (ASLE)+AFB1 (100 mg/kg, 200 mg/kg, and 300 mg/kg body weight [b.w.]) treated groups. Annona senegalensis is a good candidate for hepatoprotective agents and thus its use in traditional medicine may at least in part be justified. Contribution: The plant extract investigated in this study can be used in animal health to protect the organism from toxicity caused by mycotoxins.

Anti-nutritive and toxic factors in plants adversely affect animal health and production. Hence, the aims of the study were to (1) carry out qualitative and quantitative analysis of these factors in Terminalia sericea that grows abundantly in Onderstepoort; (2) evaluate an affordable, efficient and reliable method that reduces these factors and (3) evaluate antioxidant properties of the phenolic compounds. Thus, sequential organic and aqueous extractions were carried out on T. sericea leaves and feed pellets. Extracts were subjected to qualitative analysis to confirm the presence of 11 phytochemicals. While quantitative analysis of nine phytochemicals was carried out on spectrophotometry, the phenolic extracts were further tested for antioxidant activity on 2,2-diphenyl-picrylhydrazyl (DPPH) assay where gallic acid (GA), quercetin (Q) and ascorbic acid (AA) were used as standards. The contents of GA, Q and AA in the phenolic extracts were determined on high-performance liquid chromatography (HPLC). Aqueous extraction was an effective method as most phytochemicals were extracted. Nine phytochemicals were qualitatively analysed in T. sericea. The highest contents of 1.97% and 2.37 ± 0.077 mg/g gallic acid equivalent with a significant difference (p  0.05) were determined in oxalates and phenolics, respectively. Furthermore, 83.1% DPPH inhibition (IC50 = 0.0432 µg/mL) was determined relative to the standards (85.27% – 85.96%; IC50 = 0.000009 µg/mL – 0.00042 µg/mL). Subsequently, HPLC results showed that T. sericea contained high concentration of AA (62.5 ± 2.13 µg/mL) to confirm antioxidant properties of the leaves. Contribution: Though T. sericea leaves have antioxidant activities, the alkaloid contents may pose a threat to the livestock. Therefore, farmers around Onderstepoort should protect their livestock from feeding on these leaves.

Natural treatment options for Microsporum canis dermatophytosis are being explored because of resistance to several antifungal medications. In this study, the potential antifungal effect of bee venom (BV), a natural antimicrobial agent, on M. canis was investigated. The antifungal effects of BV, fluconazole, itraconazole, amphotericin B and terbinafine were evaluated by the macrodilution method at various concentrations by modifying the microdilution method recommended by the European Committee on Antimicrobial Susceptibility Testing. All isolates were observed to be susceptible to terbinafine and fully resistant to fluconazole and amphotericin B. Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values of M. canis isolate 2 (Mc2) were determined as 8 µg/mL for itraconazole. The MIC and MFC values of BV were found to be 320 µg/mL for the Mc2 isolate and 640 µg/mL for the Mc6 isolate. The results showed that the isolates obtained from clinical samples in this study were highly resistant to all antifungal agents, except terbinafine. The increase in resistance indicates that antifungal drugs will become insufficient and ineffective over time and natural products such as BV should be evaluated as alternatives. Contribution: Although there are many drugs for the treatment of M. canis, the increase in resistance to antifungal agents reveals the need for the identification and development of new natural agents. Bee venom, which has been shown to have a safe and weak allergenic effect in various studies, can be tested for usability as a local antifungal drug when supported by in vivo studies.

Plant foliages used as feed additives pose a health risk due to high oxidant concentrations. Oxidants cause oxidative stress and high rate of morbidities and mortalities. Hence, the aim of the study was to validate the methods to quantify gallic acid (GA) and quercetin (Q) as putative antioxidants, and to evaluate antioxidant activities in feed (F), Hyperacanthus amoenus (HA) and Carissa bispinosa (CB) extracts. Extraction was carried out with 62.5% methanol. Method validations for linearity, accuracy and precision were performed on high performance liquid chromatography. Quantitative analysis of GA and Q and testing of 2,2-diphenyl-2-picrylhydrazyl (DPPH) scavenging activities in the extracts were performed. The lowest limit of detection (LOD) and limit of quantitation (LOQ) of 0.011 µg/mL and 0.032 µg/mL were determined in HA, respectively. The methods were accurate and precise as the relative standard deviations (%RSD) were less than 15%. The GA concentrations in CB and HA extracts were statistically significant (p  0.05) and their values were 0.65 ± 0.03 x 106 µg/kg dry weight (DW) (0.13%) and 0.28 ± 0.06 x 106 µg/kg DW (0.002%), respectively. All extracts showed very strong radical scavenging activities with their IC50 values ranging between 5.87 µg/mL and 6.86 µg/mL. Contribution: These accurate, repeatable, precise and reliable methods can be used to provide a valuable basis for GA and Q analysis in various shrub foliages. Though high GA concentrations have potential to act as antioxidants, they may have adverse health and growth performance effects when used as feed additives, while lower Q concentrations may have no effects on livestock.