Austral Journal of Veterinary Sciences

Decontamination protocols on bovine fecal and environmental samples for Mycobacterium avium ssp. paratuberculosis growth in solid media

2023-07-04T10:32:56-04:00

Bacteriological culture of Mycobacterium avium subsp. paratuberculosis (MAP) is considered the gold standard to confirm its presence in several matrices for Johne’s disease diagnosis. Whether it is a liquid or solid culture, a problem with MAP culture is that non-interpretable results arise because of overgrowth by other microorganisms, making MAP growth and identification more difficult or impossible. We systematically reviewed published decontamination protocols and their effects on MAP culture from bovine fecal and environmental samples on solid media. Based on our findings, we suggest a step-by-step decontamination protocol. The OVID^®/MEDLINE, PubMed^®, SciELO Citation Index^®, and Redalyc^® platforms as well as the International Colloquium on Paratuberculosis (ICP) proceedings and the reference lists were reviewed to identify relevant studies. The inclusion criteria considered articles published in English, Portuguese, French, German, Spanish, and peer-reviewed journals. The exclusion criteria included unrelated topics, species other than bovines, other than environmental/faecal samples, other than diagnostic techniques of interest, and non-original articles. Definitive studies were obtained through the authors’ consensus regarding their eligibility and quality. In total, 1,004 publications matched the search terms, and 27 articles met the inclusion criteria, of which 45 derived and reported 15 different decontamination protocols. The centrifugation-one-step hexadecylpyridinium chloride protocol, which used over 22,154 fecal samples in three studies, was found to be the most suitable, reporting an average MAP isolation rate of 3.99% (886/22,154) and an average contamination rate of 0.17% (38/22,154). This systematic review highlights the need for further refinement of decontamination protocols to minimize the loss of viable MAP during processing of bovine fecal and environmental samples.

Selenium affects genes associated with immunity and apoptosis in in vitro follicles of ewes

2023-03-20T10:10:16-03:00

Selenium plays an important role in bodily functions. It activates immune cells such as neutrophils and immunity through T cells. However, its role in ovarian follicular gene expression has not been reported. The effects of selenomethionine (SeMet) on gene expression in in vitro ewe follicles and their relationship with immunity and apoptosis were studied. Preovulatory follicles were randomly cultured, and SeMet was added to the culture, followed by incubation for 24 h. Total RNA was extracted from follicles and placed on a microarray chip. Gene expression was analyzed using GenArise and classified using the DAVID v6.8 bioinformatics program based on the Gene Ontology and Kyoto Encyclopedia for Genes and Genomes (KEGG). Gene pathways were designed using Cytoscape v3.7.2. There were 2,538 differentially expressed genes (DEGs): 1,228 upregulated and 1,310 downregulated. The upregulated genes were classified into 32, 18, and 12 nodes related to biological processes, cellular components, and molecular functions, respectively. KEGG assigned these genes to 41 metabolic and signaling pathways. 94 genes were involved in eight pathways associated with immune processes. The expression levels of CD8, NFAT2, and CD48 were quantified using RT-qPCR. Selenium activated gene expression in the in vitro preovulatory follicles of ewes, some of which were related to the immune system. The relationship among CD8, NFAT2, and CD48 genes suggests a possible immune pathway related to follicular apoptosis regulation.

Carvacrol-loaded invasomes efficacy against multidrug resistant isolates of Enterobacteriaceae and housefly

2023-08-04T09:28:04-04:00

The current study aimed to evaluate the antimicrobial activity of carvacrol-loaded invasomes (CLI) against multidrug-resistant (MDR) Enterobacteriaceae and its mechanical vector, the housefly. CLI were prepared and characterized in the laboratory. Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica subsp. enterica serovar Enteritidis, Salmonella enterica subsp. enterica serovar Typhimurium, and Klebsiella oxytoca were among the MDR enterobacteriaceae stains investigated. These strains were first isolated and identified from naturally infected chickens. The antibacterial activity of CLI against the MDR isolates was evaluated using the diffusion method. In addition, the insecticidal activity of CLI against housefly larvae and pupae was tested. The MDR index of all evaluated isolates was greater than 20%, indicating that they were all multidrug-resistant. CLI decreased the growth of all isolates except S. Typhimurium and P. aeruginosa at a dose of 0.0125%; however, pure carvacrol inhibited the growth of only Klebsiella oxytoca. Furthermore, both CLI and pure carvacrol inhibited Klebsiella oxytoca growth at different concentrations. CLI inhibited E. coli and S. enteritidis at lower concentrations than pure carvacrol, even at a doubled concentration. Carvacrol and CLI caused significant larval mortality even at low concentrations, with LC50 reached at concentartions of 2.54 and 2.19 µl/ml, respectively. Furthermore, at a low concentration of 3.125 µl/ml, both elicited a high percentage inhibition rate (PIR) in pupae. In conclusion, CLI demonstrated substantial antibacterial action, particularly against MDR isolates, as well as pesticide activity against houseflies.

The 2022 Crimean-Congo Hemorrhagic Fever outbreak in Iraq

2023-04-17T11:24:35-04:00

Crimean-Congo Hemorrhagic fever (CCHF) is an endemic, zoonotic, viral, and tick-borne disease that causes hemorrhagic symptoms. The disease has been reported in Iraq since 1979 comprising six cases between 1989 and 2009. Subsequently, 11, 3, and 33 cases were reported in 2010, 2018, and 2021, respectively. This study describes the 2022 Crimean-Congo Hemorrhagic fever virus (CCHFV) outbreak in different Iraqi governorates. In the 2022 outbreak, 212 cases of human CCHFV were reported between January 1 and May 22. These included 97 (46%) cases confirmed by reverse transcriptase polymerase chain reaction (RT-PCR) and 115 (54%) suspected cases. Most human cases have been reported for livestock breeders and butchers. Approximately half of the confirmed cases (48%) were reported in the Dhi Qar governorate, whereas the others were reported in Missan, Muthanna, Wasit, Diwaniya, Karkh/Baghdad, Rusafa/Baghdad, Kirkuk, Basra, Najaf, Nineveh, Babylon, and Karbala. Patients with CCHFV showed symptoms of the pre-hemorrhagic phase, including sudden fever, anorexia, vomiting, diarrhea, headache, nose bleeding, and abdominal and joint pain. Later, hemorrhagic symptoms started with unexplained bleeding lesions, ranging from small petechiae to large hematomas. The factors responsible for the re-emergence of CCHFV included a shortage of veterinary services during the COVID-19 pandemic and illegal slaughtering of animals outside the abattoirs. This led to massive tick infestations that acted as viral vectors.

In conclusion, this is the first report documenting the 2022 CCHFV outbreak in Iraq, with a total of 212 patients and 27 overall deaths, including 13 laboratory-confirmed cases. The authors recommend improving veterinary services provided to farmers. Additionally, future studies need to be done including the sero-epidemiology and molecular studies on local livestock and ticks to understand their roles in circulating the virus to humans.

Effects of selling through an auction market on physiological variables in beef calves

2023-08-10T10:45:05-04:00

In Chile, selling cattle through auction markets is common, and involves various stressful events. The objective of this study was to determine the effects of selling weaned beef calves through an auction market on indicators of physiological stress. Considering that transportation is invariably linked to any commercialization procedure, we compared the effects of exposing calves to transport and sale through an auction market versus transporting them directly between farms. Twenty calves of 175 (+/-37.5) kg live weight were transported from their origin farm to an auction market (2.5 h journey), where 10 calves were unloaded and exposed to regular handling within the market (unloading, sorting, regrouping, penning, sale yard showing) and thereafter loaded and transported back to the farm (TM). The remaining 10 calves were not unloaded at the market and were immediately transported back to the farm, simulating a direct sale (TD). Data collection (blood samples, body temperature, and live weight) was performed at the farm in both groups before loading (initial, 0 h), at the end of the process, after unloading TM calves back on the farm (after unloading, 12 h), and during recovery at 24, 48, and 72 h after the initial sampling. We used mixed-effects models to compare treatments and samplings. No differences were found between treatments in terms of live weight loss, maximum eye temperature, plasma beta-hydroxybutyrate, and serum cortisol concentrations. The rectal temperature was higher (p < 0.05) in TM after treatment and remained higher (p > 0.05) in the samples than in TD. Calves that passed through the market showed higher (p < 0.05) plasma CK activity after unloading (12 h) than did those that did not. The mean glucose concentration increased (p < 0.05) at 12h and remained higher than the initial value (0 h) in both the calf groups. This was a preliminary study, and according to the results, experiments should be repeated to test more animals under different situations and premises.

Identification of potentially harmful bacterial genera of veterinary relevance in the Llanquihue urban wetlands

2023-09-21T09:45:53-03:00

Water bodies constitute natural, social, and ecological heritage under constant threat from the footprint of human action. They are the habitats of many species and play a key role in sustaining biodiversity in different ecosystems. However, anthropogenic activity can result in eutrophication of water bodies, favoring the excessive growth of microorganisms, which can be a risk factor for animal, human, and environmental health. The Agricultural and Livestock Service [Servicio Agrícola y Ganadero, (SAG)] of Chile developed a list of Mandatory Reportable Diseases (MRD) to report suspected contagious diseases of veterinary relevance. In this sense, the detection of microorganisms in water bodies for the characterization of their sanitary status is important for the development of monitoring strategies and the prevention of possible diseases. This study aimed to determine the presence of potentially harmful bacteria in Llanquihue urban wetlands. Here, we used metagenomic sequencing of amplicons to characterize the composition of microorganisms in three urban wetlands in the city of Llanquihue, which could be a risk factor for animal health. Our main finding was the detection of genera that may be associated with MRD, in addition to other microbial genera that have pathogenic potential. On the other hand, we also report the presence of cyanobacteria genera that can be involved in toxin production in water bodies as another potential source of risk. This is the first study to use massive sequencing techniques to analyze the sanitary status of urban wetlands in the city of Llanquihue.

Experimental assessment of the efficacy of copper ion treatment against penicillin G contained in UHT milk and PBS

2023-09-15T10:10:55-03:00

Antibiotics are widely used in animal production to treat bacterial infections and to improve performance and animal welfare. Their misuse poses a threat to public and animal health because of the possible development of antibiotic-resistant microorganisms. Among the many strategies that have been considered to address this problem are methods to degrade antibiotic residues, especially those from the human and animal food chain. This study describes the effect of copper ion treatment on the detection of penicillin G in a liquid matrix. An in vitro experimental study was designed using both commercial milk and PBS spiked with three different concentrations of penicillin G. Each sample was treated for 30 min with copper ions. All samples were tested for antibiotics before and after treatment using a commercial enzyme-linked receptor binding assay. Additionally, pH, copper concentration, and temperature were evaluated. Antibiotic residues were detected in all spiked PBS and milk samples before treatment with copper ions. However, after 30 min of treatment, no antibiotic residues were detected in any sample at any concentration tested. In conclusion, treatment of penicillin-contaminated milk and PBS samples with copper ions affects antibiotic detection, which would potentially reduce antibiotic levels.