Water Quality In Farms Research Articles

Evaluación de la calidad del agua para uso agropecuario en predios ganaderos localizados en la región del Sumapaz (Cundinamarca, Colombia)

Objetivo: evaluar la calidad de agua en pequeñas y medianas unidades de producción ganaderas de la región de Sumapaz (Cundinamarca, Colombia). Materiales y métodos: el muestreo se realizó colectando 50 mL de agua en bolsas estériles, para la determinación de contaminación microbiológica incluyendo presencia de aerobios mesófilos, coliformes totales, Escherichia coli y Pseudomonas sp. de acuerdo con los parámetros permisibles de potabilidad definidos en el decreto 1575 de 2007 del Ministerio de la Protección Social de la República de Colombia. Resultados: se evidenció contaminación microbiana en 16 (66,7%) de los 24 predios evaluados de acuerdo con la normatividad descrita. También, se detectó la presencia de aerobios mesófilos, coliformes totales, Escherichia coli y Pseudomonas sp. en al menos el 25% de los predios evaluados. Conclusiones: los hallazgos sugieren que el agua podría representar una fuente de contaminación microbiológica directa para la salud humana, producción pecuaria y a la vez afectar la cadena de comercialización de productos lácteos y cárnicos en la provincia del Sumapaz.

Water quality in turkey farms in Khemisset (Morocco) and potential risk factors.

The objectives of this study were to assess the microbiological and physical/chemical quality of water in broiler turkey farms in the province of Khemisset (north-western Morocco) and, based on a questionnaire, to ascertain potential risk factors for contamination of drinking water with faecal coliforms. A total of 80 samples were collected and analysed in 20 farms (four from each farm). At the main inlet to the water line at the entrance to each turkey house, 100% of the samples were of unacceptable quality in terms of faecal coliforms, Escherichia coli, faecal streptococci, sulphitereducing anaerobes and enterococci. A significant reduction in microbiological contamination of the water line (p < 0.05) was observed on Day 60. While more than 90% of the samples were of satisfactory quality in terms of pH, nitrites, conductivity, nitrates and iron, only 35% were satisfactory in terms of total hardness and only 20% met quality standards for ammonium content. The factors affecting levels of contamination with faecal coliforms were water chlorination (p = 0.065; odds ratio = 14; 90% confidence interval [CI] = 1.14-71), cleaning and disinfection (p = 0.028; odds ratio = 14; 95% CI = 1.25-156.6) and antibiotic treatment (p = 0.001; odds ratio = 6; 95% CI = 2.1-35.2). To improve water quality in poultry farms, farmers are advised to protect wells from contamination and to install water purification units (pre-oxidation, coagulation, flocculation, disinfection). In addition, turkey houses and rearing equipment should be rigorously cleaned and disinfected between each batch of birds.

Biochemical and PCR Assay for Detection of Pathogenic Bacteria at Shrimp and Shrimp Farms in Bangladesh

The study was conducted to detect faecal coliforms and pathogenic bacteria in shrimp and shrimp farms. Although coliforms are widely distributed in the environment, but only a small percentage are pathogenic to humans. The presence of pathogenic bacteria in shrimp causes several waterborne infections in humans that are worldwide concerning issues. In order to better determination of the health risks that are associated with the exposure to pathogenic bacteria, a multiplex PCR system was used for the rapid detection of pathogenic Aeromonas sp., Clostradium sp., Listeria sp., Salmonella sp., Shigella sp., Vibrio sp. and Staphylococcus sp. in the water, sediment and shrimp. The target genes were chosen for this investigation included: Aer gene for Aeromonas sp., hilA gene for Salmonella sp., virA gene for Vibrio sp., Sec gene for Staphylococcus aureus, neurotoxin gene type A, B, E, F for Clostridium botulinum, internalin gene for Listera sp. andipaH gene for Shigella sp. Seven pairs of specific primers were used to amplify internal fragments of these genes by PCR to generate PCR products that could be analyzed and confirmed with relative ease by gel electrophoresis. The presence of Aeromona and Vibrio sp. were found in the water, sediment as well as in the shrimp that were dominant among other bacteria species. On the other hand, Salmonella and Clostridium group was found in the sediment of one sample but there is no evidence of Listeria, Staphylococcus and Shigella group in the farms. All of the samples contained relatively large number (1100 to ≥2400 cfu/g) of coliform bacteria. The unhygienic condition and polluted water source could be the major reasons for the occurrence of these types of pathogenic bacteria in the shrimp farms in this area. The result revealed that the PCRbased rapid detection system described in this study is a powerful method for routine monitoring and risk assessment of water quality in the shrimp farms and could be an effective tool for disease studies in our shrimp sector.

Effect of different mangrove-to-pond area ratios on influent water quality and WSSV occurrence in Penaeus monodon semi-intensive farms using the greenwater culture technique

White spot syndrome virus (WSSV) has been affecting the shrimp industry worldwide for two decades now. It continues to bring economic losses to affected farms. Despite the many studies on its epidemiology, there is no proven treatment or control measure. Diseases, like the WSSV, results from the interaction of three factors: host, pathogen and environment. The environment plays an important role in disease development and determines the health or the immune capacity of the shrimp. High mangrove-to-pond area ratio (MPR) is reported as a protective factor against WSSV. This study investigates if mangroves affect the physicochemical properties of the water and soil as well as the prevalence of infectious agents like the WSSV by monitoring farms with different MPR (0:1, 1:1, 4:1).Results showed that quality of influent water was not significantly better in farms with high MPR. Significantly higher available sulfur was observed in MPR-4; significantly higher percentage green vibrios in the soil in MPR-0. WSSV was detected in farms with MPR-1 and MPR-4 but did not result in an outbreak, suggesting that the presence of mangroves could prevent WSSV outbreak.

Caracterização da mastite subclínica em caprinos produzidos em sistema orgânico no Rio Grande do Sul

O leite e derivados são reconhecidos como veículos de patógenos para humanos, secundário a contaminação pós-ordenha ou de infecções do próprio animal, particularmente na mastite. Foi estudada a ocorrência de mastite e aspectos do manejo em cabras de três propriedades criadas em sistema orgânico. O exame clínico da glândula mamária de 64 cabras em diferentes períodos de lactação, não acusou a presença de mastite clínica. Entretanto, o Califórnia Mastitis Test (CMT) identificou 54 (22,7%) metades mamárias reagentes (+ ou ++). Foram colhidas 238 amostras de leite, das quais houve isolamento bacteriano em 37 (15,6%). Em apenas oito amostras houve coincidência entre o isolamento bacteriano e o resultado do CMT, indicando sensibilidade de 21,6% para este teste no diagnóstico de mastite subclínica em caprinos. Staphylococcus coagulase negativa (SCN) foi o microrganismo mais freqüente (83,8%). O teste de sensibilidade microbiana in vitro revelou resistência das linhagens de SCN ao cotrimoxazol (50%), ampicilina (48,1%), nitrofurantoína (7,7%), cefaclor (7,14%) e oxacilina (3,85%). Cefalotina, gentamicina, neomicina, estreptomicina e tetraciclina foram os antimicrobianos mais efetivos frente aos isolados. Não se evidenciou relação entre a ocorrência de mastite subclínica com a raça, a fase de lactação, sistema de ordenha ou qualidade da água utilizada nas propriedades.

Removal of pathogenic bacteria and nitrogens by Lactobacillus spp. JK-8 and JK-11

The feasibility of using Lactobacillus strains for the simultaneous removal of pathogenic bacteria and nitrogens, with the ultimate aim of application for the improvement of water quality in shrimp farms, was explored. Initially, strains of Lactobacillus spp. JK-8 and JK-11 in shrimp ponds were screened for their ability to remove pathogenic bacteria and nitrogen compounds. At the end of the incubation period in cultures of JK-8 and JK-11, JK-8 had produced 192.8 mM lactic acid and 43.6 mM acetic acid, and the pH of the culture had decreased from 7.0 to 3.8. However, the JK-11 strain produced only small amounts of organic acids, and the pH of the culture decreased from 7.0 to pH 5.4. Pathogen survival following exposure to concentrated cell-free supernatants derived from JK-8 and JK-11 cultures was also investigated. Pathogens were completely removed within 4 min of exposure to either culture supernatant. Cell-free supernatants concentrated from pH-nonadjusted JK-8 cultures and either pH-adjusted or pH-nonadjusted JK-11 cultures demonstrated remarkable antimicrobial activities against target bacteria (e.g., Vibrio parahemolyticus, V. harveyi, Edwardsiella tarda). Scanning electron microscopy analyses revealed perforations in bacterial cells and irregular rod shapes with wrinkled surfaces following incubation with the concentrated supernatants. Both JK-8 and JK-11 cultures facilitated the removal of up to 400 µM NH 4 +, NO 2 −, and NO 3 −. The results of this work are applicable for the simultaneous removal of pathogens and nitrogens from contaminated shrimp farms.

Impact of culture intensity and monsoon season on water quality in Thai commercial shrimp ponds

The present authors investigated the impact of farming intensity and the prevailing season on water quality in intensive tropical shrimp farms. The weekly water quality samples from the inlets and production ponds of two commercial shrimp farms operating partial water exchange schedules and representing low and high farming intensities in Thailand (with Penaeus monodon Fabricius production rates of 4 and 9 t ha ‐1 cycle ‐1 , respectively) were analysed over two consecutive production cycles, covering the wet (monsoon) and dry seasons. Significant differences in inlet water quality between farms occurred only in salinity, temperature and suspended solids. The present authors assessed impacts of farming intensity and season on production pond water quality parameters using: (1) an analysis of variance (ANOVA) of measurements in replicate ponds during the final month of the production cycle; and (2) a trend analysis which classified trends in parameters over the cycle as externally or internally determined. The prevailing season was found to have a strong impact on salinity, temperature, pH, nitrate, dissolved reactive phosphorus, total phosphorus and dissolved oxygen in the final month of the cycle. The trends in these parameters were largely externally determined or absent. Nitrite and chlorophyll a were affected by production intensity in interaction with season and showed mainly internally determined trends. This indicates that nitrogen transformation processes responded to input levels as well as seasonal influences. Ammonia was highly variable and no significant intensity or season effects were detected, but trends were internally determined only at high intensity and more pronounced in the dry rather than the wet season. The results indicate strong seasonal effects on water quality in tropical shrimp ponds, direct in some parameters and indirect in others, including those linked to nitrogen transformations. The mechanisms of seasonal variation and the implications of these changes for water quality management call for further investigation.