Laboratory analysis as support to slaughterhouse inspection in Songea cattle abattoir (Tanzania): A public health perspective.

Livestock breeding is one of the main agricultural activities in Tanzania, recognized as one of the African countries with the greatest livestock resources. Cattle is the most widely bred animal species, especially with traditional farming methods such as pastoralism and agro-pastoralism. Slaughtering takes place mainly in rural slaughter slabs and municipal slaughterhouses, and according to local legislation it must be supervised by Official Veterinarians, who report any organs to be discarded and, after stamping the carcass, authorize its free consumption. Since the Ruvuma region lacks data on cattle diseases, the aim of this study was to collect information at Songea slaughterhouse, with particular attention to conditions of parasitic aetiology and potential zoonotic interest, deepening inspective diagnoses by means of parasitological and histological investigations on tissue samples. Overall, the slaughter data of 614 animals are reported. In most cases slaughtered cattle belonged to local breeds and came from the Mbeya region. Fasciolosis (diagnosed in 44.6% of animals) was the most frequent condition, followed by respiratory diseases (24.4%), aortic onchocerciasis (6.5%), hydatidosis (5.5%) and bovine cysticercosis (3.4%). Laboratory analysis identified Fasciola gigantica as the species involved in hepatic distomatosis in this area. Cases macroscopically ascribed to cysticercosis turned out to be a muscular form of onchocerciasis (by Onchocerca dukei), a neglected and unrecognised parasitic disease in Tanzania, questioning the real frequence of a zoonosis that causes primarily major economic losses. Pulmonary cysts, referred as hydatidosis at visual inspection, were histologically identified as haemal nodes, lymphoid organs common in ruminants, but described in cattle lungs for the first time in the present paper. Slaughterhouse is an important epidemiological observatory, especially for neglected parasitoses. The possibility of having basic laboratory diagnostics as an aid to visual inspection can ensure greater efficiency of veterinary services in the control of important livestock diseases and zoonoses, in the frame of a One Health perspective.

Phenotypic and Genotypic Analysis of Antimicrobial Resistance in Escherichia coli Recovered from Feedlot Beef Cattle in Australia.

This study investigated the antimicrobial resistance (AMR) profile of fecal Escherichia coli isolates from beef cattle (n = 150) at entry and exit from an Australian feedlot. Sample plating on MacConkey agar and Brilliance ESBL agar differentiated generic from extended-spectrum ß-lactamase (ESBL)-producing E. coli, respectively. Resistance profiles were determined by minimum inhibitory concentration (MIC) testing and further analyzed by whole-genome sequencing (WGS). At entry, the prevalence of antimicrobial resistance to amoxicillin/clavulanic acid, ampicillin, streptomycin, and trimethoprim/sulfamethoxazole was very low (0.7%, each). At the exit, the resistance prevalence was moderate to tetracycline (17.8%) and low to ampicillin (5.4%), streptomycin (4.7%), and sulfisoxazole (3.9%). The most common AMR genes observed in phenotypically resistant isolates were tet(B) (43.2%), aph(3″)-Ib and aph(6)-Id (32.4%), blaTEM-1B, and sul2 (24.3%, each), which are responsible for resistance to tetracyclines, aminoglycosides, ß-lactams, and sulfonamides, respectively. The ESBL-producing E. coli were recovered from one sample (0.7%) obtained at entry and six samples (4.0%) at the exit. The ESBL-producing E. coli harbored blaTEM (29.7%), blaCTX m(13.5%), and blaCMY (5.4%). The resistance phenotypes were highly correlated with resistance genotypes (r ≥ 0.85: p < 0.05). This study demonstrated that E. coli isolated from feedlot beef cattle can harbour AMR genes, but the low incidence of medically important resistance reflected the prudent antimicrobial use in the Australian industry.

Monensin occurrence in surface water and its impact on aquatic biota in a stream of the southeast Pampas, Argentina.

Monensin is an ionophore antibiotic used as a feed additive and growth promoter in cattle production worldwide. The occurrence of monensin in aquatic surficial ecosystems is of concern due to its possible detrimental effects on human health and native biota. Argentina is one of the most important cattle beef producers worldwide; however, there is little knowledge on the environmental occurrence of monensin and the associated risks to aquatic biota. In this study, we developed a method for the extraction and quantification of monensin in surface water; then, we evaluated the occurrence of monensin in a stream impacted by different animal husbandry's operations, and then, we analyzed the ecological implications of monensin residues on aquatic organisms using the risk quotient (RQ) method. Sampling was carried out on August 2017 from the headwaters to the floodplain of the El Pantanoso stream, Buenos Aires province, Argentina. Monensin detection frequency was 75% (n = 20). The median level was 0.40 µg/L and the maximum concentration was 4.70 µg/L. The main input of monensin was from a cattle slaughterhouse, an activity that has not been considered before in the literature as a source of emission of veterinary pharmaceuticals into the environment. The RQ assessment showed that monensin levels could have potential negative effects on aquatic biota in the sampling site closest to the cattle slaughterhouse. The data obtained in this study shows that monensin was present in El Pantanoso surface waters at levels of high ecotoxicological risk to aquatic biota.

A Comparative Study of Biogas Production from Cattle Slaughterhouse Wastewater Using Conventional and Modified Upflow Anaerobic Sludge Blanket (UASB) Reactors.

Cattle slaughterhouses generate wastewater that is rich in organic contaminant and nutrients, which is considered as high strength wastewater with a high potential for energy recovery. Work was undertaken to evaluate the efficiency of the 12 L laboratory scale conventional and a modified upflow anaerobic sludge blanket (UASB) reactors (conventional, R1 and modified, R2), for treatment of cattle slaughterhouse wastewater (CSWW) under mesophilic condition (35 ± 1 °C). Both reactors were acclimated with synthetic wastewater for 30 days, then continuous study with real CSWW proceeds. The reactors were subjected to the same loading condition of OLR, starting from 1.75, 3, 5 10, 14, and 16 g L-1d-1, corresponding to 3.5, 6, 10, 20, 28, and 32 g COD/L at constant hydraulic retention time (HRT) of 24 h. The performance of the R1 reactor drastically dropped at OLR 10 g L-1d-1, and this significantly affected the subsequent stages. The steady-state performance of the R2 reactor under the same loading condition as the R1 reactor revealed a high COD removal efficiency of 94% and biogas and methane productions were 27 L/d and 89%. The SMP was 0.21 LCH4/gCOD added, whereas the NH3-N alkalinity ratio stood at 651 mg/L and 0.2. SEM showed that the R2 reactor was dominated by Methanosarcina bacterial species, while the R1 reactor revealed a disturb sludge with insufficient microbial biomass.

Effect of Organic Loading Rate on Anaerobic Digestion Performance of Mesophilic (UASB) Reactor Using Cattle Slaughterhouse Wastewater as Substrate.

In this study, the performance of a laboratory scale upflow anaerobic sludge blanket (UASB) reactor operating at mesophilic temperature (35 °C) was examined. Cattle slaughterhouse wastewater (CSWW) was used as the main substrate. The total and effective volumes of the reactor were 8 L and 6 L, respectively. Twelve different organic loading rates (OLR) were applied and the performance was evaluated. The chemical oxygen demand (COD) removal efficiency was more than 90% during batch study. In the continuous study, COD removal was also approximately 90% at OLR 0.4 g/L d-1 which subsequently dropped to below 50% when the loading rate increased to 15 g/L d-1. Approximately 5 L/d of biogas was obtained with high methane concentration at stages VI and XI corresponding to OLR of 2 and 10 g/L d-1, respectively. It was observed that the concentration of volatile fatty acids was low and that the alkalinity of the wastewater was sufficient to avoid acidification. Specific methane yields of 0.36 and 0.38 LCH4/g COD added were achieved at OLR 7 and 10 g/L d-1. A hydraulic retention time (HRT) of 1 day was sufficient to remove greater than 70% of COD which correspond to 89% methane concentration. Parameters like soluble COD, NH3-N, pH, alkalinity, total suspended solid (TSS), fats, oil, and grease were also investigated. The results show that the UASB reactor could serve as a good alternative for anaerobic treatment of CSWW and methane production.

Comparison of the incidence of pathogenic and antibiotic-resistant Escherichia coli strains in adult cattle and veal calf slaughterhouse effluents highlighted different risks for public health.

The goal of this study was to investigate the involvement of bovine slaughterhouse effluents and biosolids in the risk of environmental dissemination of pathogenic and antibiotic-resistant Escherichia coli. Several samples were collected from one adult cattle and one veal calf slaughterhouse wastewater treatment plant (WWTP). The treatment process had no impact on the percentage of Shiga toxin-producing E. coli (STEC) and on the percentage of atypical enteropathogenic E. coli (aEPEC). A STEC O157:H7 was isolated from the thickened sludge of the adult cattle slaughterhouse. As thickened sludge is intended to be spread on agricultural lands, the detection of this pathogenic strain is a public health issue. The percentage of antibiotic-resistant E. coli was 5.0% and 87.5% in wastewater from the adult cattle and the veal calf slaughterhouse, respectively. These percentages were not significantly different after treatment. Integron-bearing E. coli isolates were only detected in the veal calf slaughterhouse WWTP with percentages above 50.0% for all sampling points whatever the step of the treatment process. Taken together, these findings highlighted the fact that different public health risks might be associated with adult cattle or veal calf slaughterhouses regarding the dissemination of pathogenic and antibiotic-resistant E. coli isolates into the environment.

Ocorrência de Escherichia coli O157: H7 e O26 sorbitol negativas em matadouro frigorífico de bovino e suscetibilidade a antimicrobianos / Occurrence of Escherichia coli O157: H7 and O26 sorbitol negative in a cattle slaughterhouse and susceptibility to antimicrobials

A carne bovina pode ser um meio de transmissão de Escherichia coli O157:H7 e de não-O157 para os humanos, que a ingerem mal cozida, sendo responsáveis por causarem doenças severas, como a síndrome hemolítico urêmica. A resistência bacteriana se tornou preocupante em relação à eficácia nos tratamentos das doenças, e tendo em vista tais aspectos este estudo teve os objetivos de verificar a ocorrência de E. coli O157:H7 e não-O157 em etapas do abate bovino, asssim como de avaliar a suscetibilidade dessas bactérias frente à ação de antimicrobianos. Foram colhidas em abatedouro bovino 21 amostras de superfície de mãos dos manipuladores, 21 de facas e 300 provenientes de 50 animais em seis pontos no fluxograma de abate. O isolamento foi realizado utilizando o ágar CT-SMAC e a caracterização dos sorotipos pela PCR. Houve uma ocorrência maior de E. coli O157:H7 (12,0%) nos animais, e menor ocorrência de E. coli O26 (8,0%) e de O113 (2,0%). E. coli O26 esteve presente em 9,52% das facas. A presença de E. coli não-O157 sorbitol negativa foi um fato inesperado devido ao método de isolamento utilizado. Todos os isolados de E. coli O157:H7 mostraram-se sensíveis à tetraciclina, cefepime, cefoxitina, ciprofloxacina e sulfazotrim, e 78,85% deles foram resistentes à cefalotina e 34,61% à ampicilina. Todas E. coli O26 foram sensíveis ao cefepime, cefoxitina e sulfazotrim, e 88,23% resistentes à tetraciclina e cefalotina e 82,35% à ampicilina. A multirresistência aos antibimicrobianos foi observada em todos os sorotipos, devendo, portanto, haver critérios no uso de antimicrobianos nos tratamentos para não se tornar um problema de saúde pública.(AU)

Cattle beef could be a way of transmitting Escherichia coli O157: H7 and non-O157 to humans if they consume undercooked meat, being responsible for causing severe diseases such as hemolytic uremic syndrome. Bacterial resistance has become worrying concerning the efficacy in the treatment of diseases, and because of these aspects, the objective of this study was to verify the occurrence of E. coli O157: H7 and non-O157 in the stages of cattle slaughter and to evaluate the susceptibility of these bacteria against antimicrobial action. We collected from a cattle slaughterhouse 21 samples from manipulators' hands, 21 from knives and 300 from 50 animals in six points of the flowchart. The isolation was performed using the CT-SMAC agar and characterization of serotypes by PCR. There was higher occurrence of E. coli O157: H7 (12.0%) in animals and lower prevalence of E. coli O26 (8.0%) and O113 (2.0%). E. coli O26 was present in 9.52% of the knives. The presence of E. coli non-O157 sorbitol negative was an unexpected fact due to the method of isolation. All E. coli O157: H7 isolates were sensitive to tetracycline, cefepime, cefoxitin, ciprofloxacin and sulphazotrim, and 78.85% of them were resistant to cephalothin and 34.61% to ampicillin. All E. coli O26 were sensitive to cefepime, cefoxitin and sulphazotrim, and 88.23% were resistant to tetracycline and cephalothin and 82.35% to ampicillin. The antimicrobial multiresistance was observed in both serotypes. It should be, therefore, a criteria for using antimicrobial in treatments to avoid become a public health concern.(AU)