Suspected Anthrax Outbreaks or Sudden Animal Deaths in Hyati Mundaragi Village in Koppal, Karnataka, India: A Farmer Prospective

Anthrax, caused by Bacillus anthracis, is a persistent global threat to both public health and livestock industries. This study investigates an outbreak of sheep anthrax in Hyati Mundaragi Village, Karnataka, India. The demographic and ecological characteristics of this region are pivotal factors influencing disease emergence, with varying outbreak years observed among sheep farmers. Socio-economic factors and Risk Exposure and Mitigation Behaviour (REMB) were found to be critical determinants of anthrax incidence, emphasizing the multifaceted nature of the disease's spread. Sheep migration and proximity to water bodies, notably the Tungabhadra reservoir, facilitated spore transfer and contributed to the outbreak in this village. The study highlights the urgency of proactive measures, including comprehensive disease surveillance, vaccine accessibility, training initiatives for local veterinarians and farmers, and the integration of AI tools for early detection and rapid response.

Comparative Study of Soil Properties and Organic Matter Fractions in Organic and Conventional Farms of Kerala, India

Aims: Assessing various soil properties as influenced by organic farming in the selected certified organic and conventional farms of Kerala.Study Design: Ten pairs of certified organic farms and nearby conventional farms were identified from different agroecological zones of Kerala and were analysed for physical, chemical and biological properties.Place and Duration of Study: The research was conducted at College of Agriculture Vellayani, between December 2020 – June 2021.Methodology: Soil samples were collected from these farms and analyzed for soil physical, chemical and biological properties, organic carbon, total nitrogen, C: N ratio and organic matter fractions.Results: Organic farms exhibited lower bulk density (1.15 Mg m-3) and higher values in porosity (41.32%), water holding capacity (52.68%), mean weight diameter (1.87%), and water stable aggregates (73.59%) compared to conventional farms. Additionally, organic farms were found to be higher in electrical conductivity (0.09 dS m-1), cation exchange capacity (5.98 C mol(p+) kg-1), total organic carbon (7.59%), total nitrogen (0.46%), and C:N ratio (16.14) in comparison to conventional farms. The concentrations of fulvic acid, humic acid, and humin are also greater in organic farms, with mean values of 5.45%, 3.56%, and 0.47%, respectively.Conclusion: Organic farming has a significant role in improving the physical, chemical and biological properties of the soil and also total carbon, total nitrogen and the organic matter fractions.

The herpetofauna of priority highland areas for conservation of the Caatinga in the state of Rio Grande do Norte, northeastern Brazil / A herpetofauna de áreas serranas prioritárias para conservação da Caatinga no estado do Rio Grande do Norte, nordeste do Brasil

Abstract The Brazilian Caatinga has already lost extensive areas of original vegetation, thus it becomes imperative to perform fauna inventories within this region to fill geographical sampling gaps. Herein, we present a taxonomic list of the herpetofauna of a mountain chain located in the central zone of Rio Grande do Norte (RN) state whose region includes two priority areas for conservation of the Caatinga: "CA087 - Serra de Santana" in the west, and "CA078 - Nascente do Potengi" in the east. The sampling was carried out using methods of visual searching, pitfall traps with drift fences, specimens rescued during vegetation suppression activities in wind energy projects, occasional encounters, and third-party records. We recorded 19 amphibian species and 53 reptile species (23 lizards, 24 snakes, five amphisbaenians and one chelonian). About half of the recorded species have distributions entirely or mostly in the Caatinga. The mountain range sampled in this study harbors virtually all species found in nearby lowlands of the "sertaneja" depression of RN state, plus some relevant species with relictual distributions in the Caatinga, highlighting the importance of these highland areas for conservation of the Caatinga herpetofauna.

Resumo A Caatinga brasileira já perdeu extensas áreas de vegetação original, por isso torna-se importante realizar inventários de fauna nesta região para preencher lacunas geográficas de amostragem. Aqui, apresentamos uma lista taxonômica da herpetofauna de uma cadeia serrana localizada na zona central do estado do Rio Grande do Norte (RN) e cuja região inclui duas áreas prioritárias para conservação da Caatinga: "CA087 - Serra de Santana" a oeste, e "CA078 - Nascente do Potengi" a leste. A amostragem foi realizada por meio de métodos de busca visual, armadilhas de interceptação e queda, espécimes resgatados durante atividades de supressão vegetal em projetos de energia eólica, encontros ocasionais e registros de terceiros. Registramos 19 espécies de anfíbios e 53 espécies de répteis (23 lagartos, 24 serpentes, cinco anfisbênias e um quelônio). Cerca de metade das espécies registradas tem distribuição inteiramente ou predominantemente na Caatinga. A cadeia serrana amostrada neste estudo abriga praticamente todas as espécies encontradas nas planícies próximas da depressão sertaneja do RN, além de algumas espécies relevantes com distribuição relictual na Caatinga, destacando a importância dessas áreas de altitude para a conservação da herpetofauna da Caatinga.

HIV in the Eastern Cape province of South Africa threatens farm employment and food security

Introduction: Human immunodeficiency virus' (HIV's) threat to food security is highest in areas with high poverty levels. The OR Tambo district in the Eastern Cape province has the highest poverty rate in South Africa (80.4%); HIV prevalence is 11.4%. Objective: The purpose of the study was to describe the threat that HIV poses to farm employment and food security in the Eastern Cape province of South Africa. Methods: A multi-method approach was used. The quantitative component was a cross-sectional design and the qualitative component was a narrative design. The study population comprised approximately 7 000 smallholder farmers from the five local municipalities in the OR Tambo district. Participants for both the qualitative and quantitative aspects of the study were selected using convenience sampling. Quantitative data were collected using questionnaires and qualitative data were collected from face-to-face interviews. Quantitative data were analysed using descriptive statistics and the chi-square test. Qualitative data were analysed using Tesch's eight-step procedure for thematic content analysis. Results: Five hundred and ninety-three farmers completed the questionnaire. Most agreed that HIV affects food security (n = 486, 72.0%), that HIV negatively affects food security (n = 454, 76.6%), that people living with HIV are excluded from farming activities (n = 426, 71.8%), and that HIV affects farming skills (n = 495, 83.5%). A significantly larger proportion of farmworkers older than 60 years than those who were younger perceived the threat to food security. Twenty participants described the effect of HIV on farm workers in interviews, and highlighted that HIV impacts farm skills and labour due to ill health and lost income from farming, which threatens food security. Conclusion: HIV threatens food security among smallholder farmers in the OR Tambo district due to farmworkers' diminished capacity to work and consequent reduced income, which affects their ability to secure food.

First record of the invasive dwarf surf clam Mulinia lateralis (Say 1822) in the eastern Pacific Ocean

Mulinia lateralis is a native bivalve from the Western Atlantic Ocean, distributed from the Gulf of Saint Lawrence in Canada to Yucatan in Mexico. Based on morphological and genetic data of specimens collected in shrimp farms, in this work, we confirm the presence of M. lateralis in the Gulf of Guayaquil, Ecuador. Presence and its consequences of this invasive bivalve in the region is discussed.

Mulinia lateralis es un bivalvo nativo de las aguas del Océano Atlántico Occidental, distribuido desde el Golfo de Saint Lawrence en Canadá hasta Yucatán en México. En este trabajo, la presencia de M. lateralis es confirmada en el Golfo de Guayaquil, Ecuador, con base en datos morfológicos y genéticos de ejemplares colectados en camaroneras. Se presenta una discusión sobre la presencia y consecuencias de este bivalvo invasor en la región.

Dinámicas de producción y emisiones modeladas de gases de efecto invernadero en sistemas regionales de producción lechera de Honduras / Production dynamics and greenhouse gas modeled emissions from regional dairy production systems in Honduras

RESUMEN El objetivo del estudio fue la caracterización productiva y de emisiones modeladas de gases de efecto invernadero (GEI) en 61 sistemas lecheros localizados en cinco regiones de Honduras. Durante las fases inicial (FI) y final (FF), con encuestas aplicadas individualmente a los productores, se identificaron aspectos técnicos y de productividad. Variables numéricas expresadas en Microsoft Excel ® permitieron, con el modelo FAO de evaluación ambiental de la ganadería global-interactivo (GLEAM-i, por sus siglas en inglés) de ciclo de vida, estimar emisiones anuales de metano (CH4), óxido nitroso (N2O) y dióxido de carbono (CO2) en cada finca. Cálculos intermedios (GEI/animal) fueron derivados de la modelización GLEAM-i en Excel®. Durante la FI las fincas conjuntamente emitieron 25.038 t CO2 equivalente (CO2-eq), mientras que dichas emisiones fueron 10,5% menores en la FF. Emisiones de GEI/animal (2,85 ± 0,08 t CO2-eq) y de GEI/kg de proteína láctea (96,91 ± 4,50 kg CO2-eq) durante la FI fue-ron 13 y 21% menores en la FF, respectivamente. Valores de 52,82 ± 1,64 (CH4) y 2,66 ± 0,10 (N2O) kg/animal en la FI fueron 13% y 17% menores en la FF, respectivamente. La región Centro-Sur-Oriente emitió la menor cantidad de CH4 (42,95 ± 2,37 kg/animal) y N2O (1,82 ± 0,15 kg/animal, mientras las regiones Occidente y Norte experimentaron una reducción del 27% en GEI/kg proteína láctea entre la FI y FF. Se concluyó que la metodologia usada identificó los impactos productivos y medioambientales, derivados de alternativas técnicas implementadas en sistemas de producción lechera de Honduras.

ABSTRACT The study aimed to characterize production dynamics and greenhouse gas (GHG) emissions from 61 dairy farms in five regions in Honduras. Farm data were collected through individual surveys during the initial and final phases (IP; FP). Using Microsoft Excel, data was incorporated into the global livestock environmental assessment model-interactive (GLEAM-i, FAO) life cycle framework to estimate annual emissions of methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2) at the farm system level. Animal emissions (GHG/animal) were derived in Excel® from the GLEAM-i predictions. Together, farms during the IP emitted 25.038 t CO2 equivalent (CO2-eq) while these emissions were 10,5% lower in the FP. Emissions of GHG/animal (2,85 ± 0,08 t CO2-eq) and GHG/kg of milk protein (96,91 ± 4,50 kg CO2-eq) during the IP were 13% and 21% lower in the FP, respectively. Methane and N2O emission values (52,82 ± 1,64 vs. 2,66 ± 0,10 kg/animal) were 13% and 17% higher in the IP than in FP. The South-Central region emitted the lowest amount of CH4 and N2O (42,95 ± 2,37 kg/animal vs. 1,82 ± 0,15 kg/animal) while 27% lower GHG/kg milk protein was observed between the IP and FP of the Western and Northern regions. It was concluded that the used methodology identified productive and environmental impacts derived from implemented technical interventions in dairy production systems in Honduras.

Preliminary assessment of weed population in vegetable and fruit farms of Taif, Saudi Arabia / Avaliação preliminar da população de plantas daninhas em fazendas de hortaliças e frutas de Taif, Arábia Saudita

A significant level of yield losses in the vegetable and fruit farms are attributed to the weed populations of the area. This study was conducted for eighteen months during 2019-2020 to assess the presence of various weed families, related species, and their densities in the vegetable (CROP A) and fruit (CROP B) farms of Taif, Saudi Arabia. During the study, fourteen and ten weed families were noted in the vegetable and fruit farms of the studied area, respectively. Poaceae family weeds (729) were significantly higher in numbers followed by the families Asteraceae (414), Chenopodiaceae (338), and Gisekiaceae (153). In the vegetable farms, two weed species of the family Poaceae including Setaria viridis (437) and Eleusine indica ssp (277) were present in the higher numbers followed by Chenopodium murale (166) of the Chenopodiaceae family. In the fruit farms, the weed species Cynodon dactylon of the family Poaceae represented the highest weed density (172) followed by Gisekia pharnaceoides L. species (153) of family Gisekiaceae and Portulaca oleracea (59) belonging to the family Portulacaceae. The vegetable and fruit farms of the Taif region face severe weed pressure that affects the cultivated crops. This study depicts a comprehensive picture of weed diversity and density in the vegetable and fruit farms of the area. The results of this study will be beneficial in developing effective weed management practices for better crop production.

Um nível significativo de perdas de rendimento nas fazendas de hortaliças e frutas é atribuído às populações de ervas daninhas da área. Este estudo foi conduzido por dezoito meses durante 2019-2020 para avaliar a presença de várias famílias de ervas daninhas, espécies relacionadas e suas densidades nas fazendas de vegetais (CROP A) e frutas (CROP B) de Taif, Arábia Saudita. Durante o estudo, catorze e dez famílias de plantas daninhas foram observadas nas fazendas de hortaliças e frutas da área estudada, respectivamente. As plantas daninhas da família Poaceae (729) foram significativamente maiores em número, seguidas pelas famílias Asteraceae (414), Chenopodiaceae (338) e Gisekiaceae (153). Nas hortas, duas espécies de plantas daninhas da família Poaceae, incluindo Setaria viridis (437) e Eleusine indica ssp (277), estavam presentes em maior número, seguidas por Chenopodium murale (166) da família Chenopodiaceae. Nas fruticulturas, a espécie de plantas daninhas Cynodon dactylon da família Poaceae representou a maior densidade de plantas daninhas (172) seguida das espécies Gisekia pharnaceoides L. (153) da família Gisekiaceae e Portulaca oleracea (59) pertencentes à família Portulacaceae. As fazendas de hortaliças e frutas da região de Taif enfrentam uma forte pressão de ervas daninhas que afeta as culturas cultivadas. Este estudo apresenta um quadro abrangente da diversidade e densidade de plantas daninhas nas fazendas de hortaliças e frutas da região. Os resultados deste estudo serão benéficos no desenvolvimento de práticas eficazes de manejo de plantas daninhas para uma melhor produção das culturas.

Measurement of resource use efficiency in corn production: a two-stage data envelopment analysis approach in Turkey / Medição da eficiência do uso de recursos na produção de milho: uma abordagem de análise de dados em duas fases na Turquia

This research analyzed the efficiency situation of corn farms operating in the Adana province of Turkey. In this context, required farm management data were collected from 111 corn farmers by using face to face survey method during the 2019-2020 cultivation season. To determine the technical efficiency (TE) levels of corn farms, Data Envelopment Analysis (DEA) was applied. Furthermore, factors that cause the inefficiency in corn farms were detected by using the Tobit regression model. According to research results, the average TE levels of corn farms in the research area under the variable return to scale conditions are reported as 0.887 (111 farms). These results suggested that if farms reduced their input use by 11.3% on average, they can achieve the same output level and be able to reach full technical efficiency. The most ineffective source in terms of farms performance is machine expenditures with 68.2% of excessive use followed by labor use. In this regard, mechanization modernization, education and training of the labor force and more sensitive fertilizers and pesticide use can increase the efficiency of corn farms. Results of the Tobit regression model indicated that factors such as experience, education, number of tractors and size of the irrigated area positively influenced the TE, whereas family size in corn farming has a negative effect.

Esta pesquisa tem como objetivo analisar a situação de eficiência das fazendas de milho operando na província de Adana, na Turquia. Neste contexto, os dados necessários de gestão da fazenda foram coletados de 111 produtores de milho usando o método de pesquisa frente a frente durante a temporada de cultivo de 2019-2020. Para determinar os níveis de eficiência técnica (TE) das fazendas de milho, foi aplicada a Análise Envoltória de Dados (DEA). Além disso, os fatores que causam a ineficiência nas fazendas de milho foram detectados por meio do modelo de regressão Tobit. De acordo com os resultados da pesquisa, os níveis médios de TE das fazendas de milho na área de pesquisa sob as condições de retorno variável à escala são encontrados em 0,887 (111 fazendas). Esses resultados sugerem que, se as fazendas reduzirem o uso de insumos em 11,3% em média, podem atingir o mesmo nível de produção e alcançar eficiência técnica plena. A fonte mais ineficaz em termos de desempenho das fazendas são os gastos com máquinas, com 68,2% do uso excedente continuado com o uso de mão de obra. Nesse sentido, a mecanização, a modernização, a educação e o treinamento da força de trabalho e o uso de fertilizantes e pesticidas mais sensíveis podem ser sugeridos para aumentar a eficiência das fazendas de milho. Os resultados do modelo de regressão Tobit indicam que fatores como experiência, escolaridade, número de tratores e tamanho da área irrigada influenciaram positivamente no TE, enquanto o tamanho da família na cultura do milho tem efeito negativo.

Preliminary assessment of weed population in vegetable and fruit farms of Taif, Saudi Arabia

Abstract A significant level of yield losses in the vegetable and fruit farms are attributed to the weed populations of the area. This study was conducted for eighteen months during 2019-2020 to assess the presence of various weed families, related species, and their densities in the vegetable (CROP A) and fruit (CROP B) farms of Taif, Saudi Arabia. During the study, fourteen and ten weed families were noted in the vegetable and fruit farms of the studied area, respectively. Poaceae family weeds (729) were significantly higher in numbers followed by the families Asteraceae (414), Chenopodiaceae (338), and Gisekiaceae (153). In the vegetable farms, two weed species of the family Poaceae including Setaria viridis (437) and Eleusine indica ssp (277) were present in the higher numbers followed by Chenopodium murale (166) of the Chenopodiaceae family. In the fruit farms, the weed species Cynodon dactylon of the family Poaceae represented the highest weed density (172) followed by Gisekia pharnaceoides L. species (153) of family Gisekiaceae and Portulaca oleracea (59) belonging to the family Portulacaceae. The vegetable and fruit farms of the Taif region face severe weed pressure that affects the cultivated crops. This study depicts a comprehensive picture of weed diversity and density in the vegetable and fruit farms of the area. The results of this study will be beneficial in developing effective weed management practices for better crop production.

Resumo Um nível significativo de perdas de rendimento nas fazendas de hortaliças e frutas é atribuído às populações de ervas daninhas da área. Este estudo foi conduzido por dezoito meses durante 2019-2020 para avaliar a presença de várias famílias de ervas daninhas, espécies relacionadas e suas densidades nas fazendas de vegetais (CROP A) e frutas (CROP B) de Taif, Arábia Saudita. Durante o estudo, catorze e dez famílias de plantas daninhas foram observadas nas fazendas de hortaliças e frutas da área estudada, respectivamente. As plantas daninhas da família Poaceae (729) foram significativamente maiores em número, seguidas pelas famílias Asteraceae (414), Chenopodiaceae (338) e Gisekiaceae (153). Nas hortas, duas espécies de plantas daninhas da família Poaceae, incluindo Setaria viridis (437) e Eleusine indica ssp (277), estavam presentes em maior número, seguidas por Chenopodium murale (166) da família Chenopodiaceae. Nas fruticulturas, a espécie de plantas daninhas Cynodon dactylon da família Poaceae representou a maior densidade de plantas daninhas (172) seguida das espécies Gisekia pharnaceoides L. (153) da família Gisekiaceae e Portulaca oleracea (59) pertencentes à família Portulacaceae. As fazendas de hortaliças e frutas da região de Taif enfrentam uma forte pressão de ervas daninhas que afeta as culturas cultivadas. Este estudo apresenta um quadro abrangente da diversidade e densidade de plantas daninhas nas fazendas de hortaliças e frutas da região. Os resultados deste estudo serão benéficos no desenvolvimento de práticas eficazes de manejo de plantas daninhas para uma melhor produção das culturas.

Staphylococcus aureus Resistentes a meticilina en animales de granja en Suramérica: una revisión sistemática

Resumen La interacción entre los seres humanos y los animales de granja aumenta el riesgo de contagio con patógenos causantes de enfermedades zoonóticas. Entre estos patógenos destacan las cepas de Staphylococcus aureus resistentes a meticilina (SARM). Inicialmente identificadas como causantes de enfermedades intrahospitalarias, hoy se sabe que estas cepas también se transmiten en la comunidad infectando, además, a distintos animales. Lamentablemente, existen pocos estudios en torno a este importante tema de salud pública, particularmente en América del Sur. Este trabajo sistematiza la información disponible en relación con la ocurrencia de cepas SARM en animales de granja en dicha región. Para ello, se realizó una revisión de la información disponible en bases de datos como Scopus, Medline y Scielo, de acuerdo a las recomendaciones de la declaración PRISMA. Se incluyeron artículos publicados en los últimos diez años, que hagan referencia la ocurrencia de cepas SARM en animales de granja, en países de América del Sur. De un total de 65 artículos, se seleccionaron 19. De estos,13 se realizaron en Brasil, dos en Ecuador, uno en Chile, Uruguay y Perú, respectivamente; un último trabajo incluye datos de varios países. La mayoría de los estudios caracterizaron cepas SARM aisladas a partir de ganado vacuno, siendo los cerdos los animales que ocupan la segunda posición de interés. En muchos de estos estudios se emplearon técnicas de biología molecular. Aunque en general no fueron reportados datos importantes como la prevalencia o el período de muestreo, destaca una elevada ocurrencia de cepas SARM multirresistentes en estos animales.

Abstract The interaction between humans and farm animals increases the risk of infection with a zoonotic pathogen. Among these pathogens, methicillin-resistant Staphylococcus aureus (MRSA) strains stand out. Initially identified as the cause of hospital-acquired diseases, it is acknowledged nowadays that these strains are also transmitted in the community, being able to infect different animals. Unfortunately, few studies on this important public health issue have been published, particularly concerning the South American region. Here we systematize the available information on the occurrence of MRSA strains in farm animals in South-American countries. For this, a systematic review of the information available in the bibliographic databases Scopus, Medline and Scielo was carried out, following PRISMA standards. Articles published in the last ten years referring the occurrence of MRSA strains in farm animals in South America were included. From a total of 65 articles, 19 were selected. Of these, 13 were conducted in Brazil, two in Ecuador, one in Chile, Uruguay and Peru, respectively; a last study includes data from several countries. Most of the studies characterized MRSA strains isolated from cattle, with pigs being the second most important animal of interest. Molecular biology techniques were used in many of these studies. Although in many cases important data such as prevalence or sampling period were not reported, a high occurrence of multidrug-resistant MRSA strains in these animals stands out.

Resumo A interação entre humanos e animais de fazenda aumenta o risco de infecção com um agente zoonótico patogénico. Entre estes agentes patogénicos destacam-se as cepas de Staphylococcus aureus resistente à meticilina (MRSA). Inicialmente identificadas como a causa de doenças adquiridas em hospitais, reconhece-se hoje em dia que estas cepas também são transmitidas na comunidade, podendo infectar diferentes animais. Infelizmente, poucos estudos sobre esta importante questão de saúde pública foram publicados, particularmente no que diz respeito à região da América do Sul. Aqui sistematizamos a informação disponível sobre a ocorrência de MRSA em animais de fazenda em países sul-americanos. Para tal, foi realizada uma revisão sistemática da informação disponível nas bases de dados bibliográficas Scopus, Medline e Scielo, seguindo as normas PRISMA. Foram incluídos artigos publicados nos últimos dez anos, referindo a ocorrência de cepas MRSA em animais de fazenda na América do Sul. De um total de 65 artigos, foram seleccionados 19. Destes, 13 foram realizados no Brasil, dois no Equador, um no Chile, Uruguai e Peru, respectivamente; um último estudo inclui dados de vários países. A maioria dos estudos caracterizou cepas de MRSA isoladas de bovinos, sendo os suínos o segundo animal de maior interesse. Em muitos de estos artigos foram utilizadas técnicas de biologia molecular. Embora em muitos casos não tenham sido comunicados dados importantes, tais como prevalência ou período de amostragem, destaca-se a elevada ocorrência de cepas multirresistentes de MRSA nestes animais.

Causes of death of sows in three Brazilian pig farms / Causas de morte de matrizes suínas em três granjas brasileiras

Sow mortality is directly related to financial losses and productive efficiency in pig farms. Despite this, diseases associated with the death of sows are poorly understood. This study aimed to determine the main causes of death of sows in Brazilian pig farms. To perform this research, three Brazilian pig farms were visited, and necropsies were performed on all sows that had died spontaneously or were subjected to euthanasia. Tissue fragments were collected for histopathological and bacteriological examination. In addition, the clinical signs, productive stage, parity, and type of death (spontaneous or euthanasia) were recorded. A total of 138 necropsies were performed, and 132 had a conclusive diagnosis. The most frequent productive stages were gestation and lactation (33.3 and 31.9%, respectively), followed by parturient sows (17.4%), cull sows (9.4%), weaning-to-estrus interval (WEI) (4.3%), and unmated gilts (3.6%). The most affected organ systems were reproductive (28%), digestive (25%), locomotor (22%), cardiovascular (9.1%), and hematopoietic (6.1%). The most frequently diagnosed conditions were uterine prolapse (16/132; 12.1%), gastric ulcer (13/132; 9.8%), suppurative arthritis (11/132; 8.3%), liver lobe torsion (11/132; 8.3%), heart failure (9/132; 6.8%), vaginal or vaginal and rectal prolapse (9/132; 6.8%), and pododermatitis (8/132; 6.1%). Although 58.2% of the deaths were due to one of these seven diseases, there was a great variability in diagnoses.(AU)

A mortalidade de porcas está diretamente relacionada a perdas financeiras e à eficiência produtiva das granjas. Apesar disso, as doenças associadas à morte de porcas são pouco conhecidas. Este estudo teve como objetivo determinar as principais causas de morte de porcas em granjas suinícolas brasileiras. Para a realização desta pesquisa, três granjas brasileiras foram visitadas e necropsias foram realizadas em todas as porcas que morreram espontaneamente ou foram submetidas à eutanásia. Fragmentos de tecidos foram coletados para exame histopatológico e bacteriológico. Além disso, foram registrados os sinais clínicos, estágio reprodutivo, ordem de parto e tipo de morte (espontânea ou eutanásia). Um total de 138 necropsias foram realizadas e 132 tiveram um diagnóstico conclusivo. Os estágios produtivos mais frequentes foram gestação e lactação (33,3 e 31,9%, respectivamente), seguidos por porcas parturientes (17,4%), porcas de descarte (9,4%), intervalo desmame-estro (IDE) (4,3%) e leitoas vazias (3,6%). Os sistemas orgânicos mais afetados foram reprodutor (28%), digestivo (25%), locomotor (22%), cardiovascular (9,1%) e hematopoiético (6,1%). As condições mais frequentemente diagnosticadas foram prolapso uterino (16/132; 12,1%), úlcera gástrica (13/132; 9,8%), artrite supurativa (11/132; 8,3%), torção do lobo hepático (11/132; 8,3%), insuficiência cardíaca (9/132; 6,8%), prolapso vaginal ou prolapso vaginal e retal (9/132; 6,8%) e pododermatite (8/132; 6,1%). Embora 58,2% dos óbitos tenham ocorrido por uma dessas sete doenças, houve grande variabilidade de diagnósticos.(AU)

Consumo y comercio de tortugas continentales en la subregión la Mojana, Sucre, Colombia / Consumption and commerce of continental turtles in the la Mojana subregion, Sucre, Colombia

Los quelonios ampliamente utilizados como fuente de alimento y para comercialización, en todo el departamento de Sucre. Esto atenta contra el buen estado de la diversidad biológica y los ecosistemas donde habitan. Se determinaron las especies que son utilizadas para dichas actividades. Para conocer la magnitud de esta situación y contribuir en lo posible a plantear medidas de mitigación, se aprovecharon las capturas realizadas por pescadores de varias localidades en la sub región La Mojana, en el departamento de Sucre y se realizaron encuestas informales a esos trabajadores. Las hicoteas fueron capturadas en periodo baja lluviosidad, cuando se encuentran ovopositando y no se tuvo en cuenta la talla para su captura. Todos los individuos fueron medidos y pesados y se les hizo palpación para determinar la presencia o ausencia de huevos oviductales. Fueron capturados más de 200 individuos de ambos sexos, pertenecientes a cuatro especies de quelonios. Una de las especies se encuentra en peligro crítico (CR) Chelonoidis carbonaria, Rhinoclemmys melanosterna está reportada como casi amenazada (NT) y Kinosternon scorpioides es vulnerable (VU). La más abundante y utilizada fue Trachemys callirostris. Las técnicas utilizadas por los pescadores no son las más adecuadas, porque no solo dañan a los animales sino al ecosistema, adicionalmente, la situación económica. La situación económica de los pescadores es muy grave y no tienen otras fuentes de empleo. Se recomienda realizar actividades de educación ambiental, capacitarlos sobre pesca racional y apoyar la creación de zoocriaderos, lo que mitigaría su extracción del ambiente natural y crearía otras fuentes de trabajo.

Freshwater chelonians are widely used as a source of food and for commercialization, throughout the department of Sucre. This threatens the good state of biological diversity and the ecosystems where they live. The species that are used for these activities were determined. In order to know the magnitude of this situation and contribute as much as possible to propose mitigation measures, the catches made by fishermen from various localities in the La Mojana sub-region, in the department of Sucre, were used and informal surveys were conducted with these workers. The hicoteas were captured in the dry period, when they are laying eggs and the size was not taken into account for their capture. All individuals were measured and weighed and palpated to determine the presence or absence of oviductal eggs. More than 200 individuals of both sexes were captured, belonging to four species of chelonians. One of the species is critically endangered (CR) Chelonoidis carbonaria, Rhinoclemmys melanosterna is reported as near threatened (NT) and Kinosternon scorpioides is vulnerable (VU). The most abundant and used was Trachemys callirostris. The techniques used by fishermen are not the most appropriate because they harm the animals and the ecosystem. The economic situation of the fishermen is very serious and they have no other sources of employment. It is recommended to carry out environmental education activities, train them on rational fishing and support the creation of breeding farms, which would mitigate their extraction from the natural environment and create other sources of work.

Evaluation of actions of the official veterinary service to mitigate outbreaks of infectious laryngotracheitis and improve biosecurity on laying hen farms

ABSTRACT: Infectious laryngotracheitis (ILT), caused by an Alphaherpesvirus (Gallid herpesvirus-1; GaHV-1), has been noticed in the region of the Terras Altas da Mantiqueira, Minas Gerais. From 2010 to 2018, the Serviço Veterinário Oficial (SVO) of the Instituto Mineiro Agropecuário (IMA), implemented measures to prevent spread of the virus to other regions and control the disease in the area. Due to the close proximity and consequent epidemiological link among farms, the region was considered a unique epidemiological unit. To check the efficiency of the ILT control measures, we carried out: (1) a seroepidemiological survey, (2) questionnaires for evaluating biosecurity measures; and (3) an evaluation of the influence of farm population density on the occurrence of ILT. In 2016, 2017, and 2018, ILT was investigated using epidemiological and clinicopathological methods, along with GaHV-1 molecular detection. Serological survey was carried out on 24 farms in the quarantined region and on 13 farms from other regions of the state. In 2010 and 2018, questionnaires were applied to collect data and determine indicators of biosecurity practices in all farms of the quarantined area. The differences were then assessed (Wilcoxons p 0.05). The results indicated positive serology throughout the region, although only on four farms (16.6%) the chickens have clinical signs, macroscopic and histological lesions of ILT. The prevalence of viral infection increased from 2016 (27%) to 2017 (50%) and was higher in farms with a high stock density (p=0.033). No disease, virus or antibodies were detected in the farms outside of the quarantined area. Although the biosecurity indicators had improved on all farms in the quarantined area (p 0.05), the virus was active and circulating in the region. The contingency measures have contained the outbreak, but biosecurity practices are paramount in the control of new outbreaks. Official control will be maintained in the region, including surveillance of new cases and biosecurity procedures to mitigate the risk of the virus reaching other regions.

RESUMO: Laringotraqueíte infecciosa (LTI), causada por um alfaherpesvírus (herpesvírus Gallid-1; GaHV-1), foi observada na região das Terras Altas da Mantiqueira, Minas Gerais. De 2010 a 2018, o Serviço Veterinário Oficial (SVO) do Instituto Mineiro Agropecuário (IMA) implementou medidas para impedir a disseminação do vírus para outras regiões do estado e controlar a doença na região interditada. Devido à proximidade e consequente vínculo epidemiológico entre as granjas, a região foi considerada uma unidade epidemiológica única. Para verificar a eficiência das medidas de controle de LTI, foram realizados: (1) pesquisa soroepidemiológica, (2) questionários para avaliar medidas de biosseguridade; e (3) avaliação da influência da densidade populacional da granja na ocorrência de LTI. Em 2016, 2017 e 2018, a LTI foi investigada usando métodos epidemiológicos e clínico-patológicos, com a detecção molecular de GaHV-1. O levantamento sorológico foi realizado em 24 granjas da região interditada e em 13 granjas de outras regiões do estado. Em 2010 e 2018, foram aplicados questionários para coletar dados e determinar indicadores de medidas de biosseguridade em todas as granjas da área interditada. As diferenças foram avaliadas (p 0,05 de Wilcoxon). Os resultados indicaram sorologia positiva em toda a região, embora apenas em quatro granjas (16,6%) as galinhas apresentaram sinais clínicos, lesões macroscópicas e histológicas da LTI. A prevalência de infecção viral aumentou de 2016 (27%) para 2017 (50%) e foi maior em fazendas com alta densidade de alojamento (p=0,033). Presença da doença, vírus ou anticorpos foram detectados nas granjas fora da área interditada. Embora os indicadores de biosseguridade tenham melhorado em todas as fazendas da área interditada (p 0,05), o vírus está ativo e circulava na região. As medidas de contingência contiveram o surto, mas as práticas de biosseguridade são fundamentais para o controle de novos surtos. O controle oficial será mantido na região, incluindo a vigilância de novos casos e procedimentos de biosseguridade para mitigar o risco de transmissão do vírus para outras regiões.

Evaluation of actions of the official veterinary service to mitigate outbreaks of infectious laryngotracheitis and improve biosecurity on laying hen farms / Avaliação de ações do serviço veterinário oficial para bloqueio de foco de laringotraqueite infecciosa e melhoria da biosseguridade em granjas de postura

Infectious laryngotracheitis (ILT), caused by an Alphaherpesvirus (Gallid herpesvirus-1; GaHV-1), has been noticed in the region of the Terras Altas da Mantiqueira, Minas Gerais. From 2010 to 2018, the "Serviço Veterinário Oficial" (SVO) of the "Instituto Mineiro Agropecuário" (IMA), implemented measures to prevent spread of the virus to other regions and control the disease in the area. Due to the close proximity and consequent epidemiological link among farms, the region was considered a unique epidemiological unit. To check the efficiency of the ILT control measures, we carried out: (1) a seroepidemiological survey, (2) questionnaires for evaluating biosecurity measures; and (3) an evaluation of the influence of farm population density on the occurrence of ILT. In 2016, 2017, and 2018, ILT was investigated using epidemiological and clinicopathological methods, along with GaHV-1 molecular detection. Serological survey was carried out on 24 farms in the quarantined region and on 13 farms from other regions of the state. In 2010 and 2018, questionnaires were applied to collect data and determine indicators of biosecurity practices in all farms of the quarantined area. The differences were then assessed (Wilcoxon's p<0.05). The results indicated positive serology throughout the region, although only on four farms (16.6%) the chickens have clinical signs, macroscopic and histological lesions of ILT. The prevalence of viral infection increased from 2016 (27%) to 2017 (50%) and was higher in farms with a high stock density (p=0.033). No disease, virus or antibodies were detected in the farms outside of the quarantined area. Although the biosecurity indicators had improved on all farms in the quarantined area (p<0.05), the virus was active and circulating in the region. The contingency measures have contained the outbreak, but biosecurity practices are paramount in the control of new outbreaks. Official control will be maintained in the region, including surveillance of new cases and biosecurity procedures to mitigate the risk of the virus reaching other regions.(AU)

Laringotraqueíte infecciosa (LTI), causada por um alfaherpesvírus (herpesvírus Gallid-1; GaHV-1), foi observada na região das Terras Altas da Mantiqueira, Minas Gerais. De 2010 a 2018, o Serviço Veterinário Oficial (SVO) do Instituto Mineiro Agropecuário (IMA) implementou medidas para impedir a disseminação do vírus para outras regiões do estado e controlar a doença na região interditada. Devido à proximidade e consequente vínculo epidemiológico entre as granjas, a região foi considerada uma unidade epidemiológica única. Para verificar a eficiência das medidas de controle de LTI, foram realizados: (1) pesquisa soroepidemiológica, (2) questionários para avaliar medidas de biosseguridade; e (3) avaliação da influência da densidade populacional da granja na ocorrência de LTI. Em 2016, 2017 e 2018, a LTI foi investigada usando métodos epidemiológicos e clínico-patológicos, com a detecção molecular de GaHV-1. O levantamento sorológico foi realizado em 24 granjas da região interditada e em 13 granjas de outras regiões do estado. Em 2010 e 2018, foram aplicados questionários para coletar dados e determinar indicadores de medidas de biosseguridade em todas as granjas da área interditada. As diferenças foram avaliadas (p<0,05 de Wilcoxon). Os resultados indicaram sorologia positiva em toda a região, embora apenas em quatro granjas (16,6%) as galinhas apresentaram sinais clínicos, lesões macroscópicas e histológicas da LTI. A prevalência de infecção viral aumentou de 2016 (27%) para 2017 (50%) e foi maior em fazendas com alta densidade de alojamento (p=0,033). Presença da doença, vírus ou anticorpos foram detectados nas granjas fora da área interditada. Embora os indicadores de biosseguridade tenham melhorado em todas as fazendas da área interditada (p<0,05), o vírus está ativo e circulava na região. As medidas de contingência contiveram o surto, mas as práticas de biosseguridade são fundamentais para o controle de novos surtos. O controle oficial será mantido na região, incluindo a vigilância de novos casos e procedimentos de biosseguridade para mitigar o risco de transmissão do vírus para outras regiões.(AU)

Awareness, Knowledge and Adaptation Practices of Farm Women in Relation to Climate Change in Northern Transitional Zone of Karnataka

Anthropogenic climate change is the topmost contemporary global issue. Climate change can potentially upset the rhythm of nature threatening the very existence of life on earth. Anthropogenic greenhouse gas emissions have increased since the pre-industrial era, driven largely by economic and population growth, and are now higher than ever. Their effects, together with those of other anthropogenic drivers, have been detected throughout the climate system and are extremely likely to have been the dominant cause of the observed warming since the mid-20th century. Further, relative to 1986-2015, warming is projected between 2.6 to 4.8°C under RCP8.5 (Representative Concentration Pathway) by the end of 21st century. So, climate change is the biggest threat to agriculture in countries around the globe as well as in India. Farmers in India are not fully aware of climate change and its indicators, causes, and impacts. Therefore, this study was conducted to know the awareness level, knowledge and adaptation practices of farm women regarding climate change. This study was conducted during 2018-19 under All India Co-ordinated Research Project on Home Science in Sulla village of Dharwad district. Simple random sampling technique was used to select 100 farm women in the village. A pre tested interview schedule was used to collect the data. Descriptive statistics were used for analysis of the data. The study revealed that all of the respondents were not aware about the increase in melting of glacier, cold wave and frequent flood. It was observed from the study that, 36 per cent of the farm women belonged to low category of awareness on indicators on climate change. It was also noticed that all of the women were not aware about changes in farming system in present climate condition. Results show that women were not aware about rapid urbanization, use of pesticides, natural disaster, burning of fossils and farm waste, use of electrical appliances and global warming as the causes of climate change. Moreover, all of the women adopted change in planting calendar, adoption of crop rotation and adoption of intercropping.

Causes of death in growing-finishing pigs in two technified farms in southern Brazil / Causas de morte em suínos de crescimento e terminação em duas granjas tecnificadas no Sul do Brasil

The aim of this study was to investigate the main causes of death in growing-finishing pigs in southern Brazil. During a one-year period (from 2018 to 2019), two industrial pig herds (18 and 20 thousand pigs each farm) in southern Brazil were monitored along the four seasons of the year (12 days per season on each farm), in order to perform necropsies of all pigs that died in that period. The two farms had an average monthly mortality rate ranging from 0.94 to 3.93% in the evaluated months. At necropsy, tissues were collected, fixed in 10% formalin solution and processed routinely for histopathological examination. When necessary, samples were sent for bacterial culture and PCR to identify etiologic agents. A total of 601 necropsies were performed, with 94.9% of conclusive diagnoses. Infectious diseases corresponded to 64.4% of conclusive diagnosis and non-infectious diseases to 35.6%. The most prevalent causes of death were: pneumonia (33%), gastric ulcers (15.4%), circovirosis (9.9%), systemic bacterial embolism (5.4%), polyserositis (4.4%), dilated cardiomyopathy and torsion of abdominal organs (4.3% each), and bacterial pericarditis (3.4%). Regarding pneumonias (199/601), the main agents identified in these cases were Pasteurella multocida, Influenza A virus and Mycoplasma hyopneumoniae, mainly in associations.(AU)

O objetivo do presente trabalho foi investigar as principais causas de morte de suínos em fase de crescimento e terminação no Sul do Brasil. Durante o período de um ano (entre 2018 e 2019), duas granjas tecnificadas de suínos no Sul do Brasil foram acompanhadas nas quatro estações (12 dias por estação em cada granja), para realização de necropsias dos suínos que morreram nesse período. As duas propriedades apresentavam mortalidade mensal média entre 0,94 e 3,93% nos meses avaliados. Na necropsia, amostras de órgãos foram colhidas, fixadas em formol 10% e processadas rotineiramente para o exame histopatológico. Quando necessário, amostras foram enviadas para o cultivo bacteriano e PCR para identificação de agentes etiológicos. Foram realizadas um total de 601 necropsias, com 94,9% de diagnósticos conclusivos. As doenças infecciosas corresponderam a 64,4% dos diagnósticos conclusivos e as não infecciosas a 35,6%. As principais causas de morte foram: pneumonias (33%), úlcera gástrica (15,4%), circovirose (9,9%), embolia bacteriana sistêmica (5,4%), polisserosite (4,4%), cardiomiopatia dilatada e torção de órgãos abdominais (4,3% cada) e pericardite bacteriana (3,4%). Com relação às pneumonias (199/601), os principais agentes associadas as lesões foram Pasteurella multocida, vírus da Influenza A e Mycoplasma hyopneumoniae, principalmente associados entre si.(AU)

Outbreak of avian aspergillosis in colonial-bred chicks (Isa Brown) in southern Rio Grande do Sul - case report / [Surto de aspergilose aviária em pintainhas (Isa Brown) de criação colonial na região sul do Rio Grande do Sul - relato de caso]

In this study we describe the epidemiology, clinical signs, and pathology of an outbreak of avian aspergillosis in alternative breeding in the southern region of Rio Grande do Sul, Brazil. Between the fifth and tenth day of life, 360 chicks from a flock of 4000 developed unspecific clinical signs and died. The birds were housed in a reused aviary litter, without previous treatment. In 11 six-day-old female ISA Brown chicks (Gallus gallus domesticus), necropsy revealed firm, yellowish-white, multinodular lesions extending from the pleura to the lung parenchyma. Histologically, a granulomatous, multifocal to coalescent pneumonia was observed. Granulomas were characterized by central necrosis, with heterophil and epithelioid macrophage infiltration and presence of countless Y-shaped intralesional septate hyphae morphologically compatible with Aspergillus spp. The diagnosis through isolation confirmed Aspergillus fumigatus. We highlight the importance of aspergillosis as a primary cause of diseases in the respiratory tract of young birds in alternative breeding. Measures to prevent aspergillosis mainly regarding the reuse of aviary litter are essential in poultry husbandry to prevent economic losses, reduce environmental contamination and mitigate the potential risk to public health.(AU)

Descrevem-se os aspectos epidemiológicos e patológicos de um surto de aspergilose aviária em criação alternativa na região sul do Rio Grande do Sul, Brasil. De um lote de 4000 pintainhas, entre o quinto e o 10º dia de vida, 360 aves apresentaram sinais clínicos inespecíficos e morreram. As aves foram alojadas em cama reutilizada do aviário, sem tratamento prévio. Na necropsia de 11 pintainhas (Gallus gallus domesticus), fêmeas, seis dias de idade da linhagem Isa Brown, foram observadas no pulmão lesões multinodulares, branco-amareladas e firmes, que se estendiam da pleura ao parênquima. Histologicamente foi observada pneumonia granulomatosa, multifocal a coalescente. Os granulomas eram caracterizados por necrose central, com infiltrado inflamatório de heterófilos, macrófagos, células epitelioides com presença de inúmeras hifas septadas intralesionais, semelhantes à letra "Y", morfologicamente compatíveis com Aspergillus spp. O diagnóstico foi confirmado pelo isolamento de Aspergillus fumigatus. Alerta-se para a importância da aspergilose como causa primária de afecções no trato respiratório de aves jovens em criações alternativas. Medidas preventivas relacionadas ao manejo dessas aves são indispensáveis principalmente quanto à reutilização da cama dos aviários, a fim de evitar perdas econômicas, reduzir a contaminação ambiental e o potencial risco à saúde pública.(AU)

Malaria Prevalence in Rice Farm Settlements South East Nigeria

Aim:Agrarian settlements in Nigeria possess a lot of factors that predisposes the populace to malaria. The present study focused on the evaluation of three-year prevalence of malaria in rice farm settlements, South-East Nigeria.Study Design:The study was a retrospective descriptive survey designed to evaluate the prevalence of malaria infection between January 2015 and December 2017. A total of 29, 458 records were examined, 21, 559 and 7, 899 from Ebonyi and Enugu States respectively for three years (2015 –2017). Male comprises 11, 453 of the records while the female was 18, 005.Place and Duration:Southeastern Nigeria \three yearsOriginal Research Article Methodology:Preparation of thick films blood smears for microscopyfollowing standard methods.Results: Overall, 12, 746 (43.3%) were positive for malaria parasites, 7, 651 (35.4%) and 5, 115 (64.8%) from Ebonyi and Enugu respectively.Prevalence of the infection was similar between male and female in Ebonyi State (35.5% vs. 35.3%, χ2= 0.044, df = 1, p = 0.834); but significantly higher in female compared to male in Enugu State (69.7% vs. 55.7%, χ2= 154.808, df = 1, p = 0.0001).Conclusion: There was high prevalence of malaria infection in rice farm settlements, south-east Nigeria

Caracterización genética de reproductores de Prochilodus magdalenae (pisces: prochilodontidae) usados en programas de repoblamiento en Colombia / Genetic characterization the stocks of Prochilodus magdalenae (pisces: prochilodontidae) used in stocking programs in Colombia

Prochilodus magdalenae es una especie de pez endémico de Colombia conocido por ser un importante recurso de interés comercial y para muchas comunidades relacionadas a las actividades pesqueras como actividad de sustento. No obstante, se ha observado un deterioro poblacional en ambientes naturales debido a factores tales como sobrepesca, fragmentación de ecosistemas, entre otros. Esto hace necesario caracterizar la diversidad genética de P. magdalenae en los sistemas reproductores de algunos centros piscícolas, que son usados para hacer repoblamientos en otras cuencas de Colombia y así proponer criterios técnicos y científicos que permitan el desarrollo de estrategias de manejo para la conservación de esta especie. Por lo anterior, en el año 2013 se recolectó tejido de aleta caudal de 1044 individuos en siete centros piscícolas, que fueron procesados en laboratorio y a través del uso de siete loci de microsatélites se evaluaron métricas genéticas tales como: heterocigosidad observada y esperada, número de alelos, índices de fijación, estadísticos F, agrupamiento bayesiano y AMOVA. Se encontró baja heterocigosidad observada, correlacionada con procesos de endogamia, que contrastan con los altos valores obtenidos en el índice de heterocigosidad esperada y la cantidad de alelos detectados en los sistemas de reproductores de P. magdalenae. Se detectó una moderada diferenciación genética entre centros piscícolas y se observó la existencia de tres grupos genéticos a través del agrupamiento bayesiano. Pese a la baja diversidad reportada con respecto a otras especies del mismo género, las poblaciones mantenidas en cautiverio de Bocachico tienen potencial para restaurar la diversidad de las poblaciones silvestres. Por lo que se sugiere que cada estación piscícola debe establecer lotes de reproductores por separado, en función de su información genética para que exista una congruencia entre los individuos liberados y aquellos que habitan en el medio natural.

Prochilodus magdalenae is an endemic fish species of Colombia known as an important resource of commercial interest for many communities related to fishing activities as a livelihood activity. However, population deterioration has been observed in natural environments due to factors such as overfishing, fragmentation of ecosystems, among others. This makes it necessary to characterize the genetic diversity of P. magdalenae in the productive systems of some fish farms, which are used to restocking in other basins of Colombia and, thus, to propose technical and scientific criteria that allow the development of management strategies for the conservation of this species. Therefore, in 2013, caudal fin tissue was collected from 1044 individuals in seven fish farms, which were processed in the laboratory. Through the use of seven microsatellites, genetic metrics such as: observed and expected heterozygosity, number of alleles, fixation indexes, F statistics, Bayesian grouping and AMOVA were evaluated. We observed low heterozygosity, correlated with inbreeding processes, which contrast with the high values obtained in the expected heterozygosity index and the number of alleles detected in P. magdalenae productive systems. A moderate genetic differentiation between fish centers was detected and the existence of three genetic groups was observed through the Bayesian analysis. Despite the low diversity reported regarding the others species of the same genus, populations held in Bocachico captivity have the potential to restore the diversity of wild populations. Therefore, it is suggested that each fish station should establish batches of breeders separately, based on their genetic information so that there is congruence between the released individuals and those that inhabit the natural environment.

Bacterias nitrificantes cultivables de la zona limnética del lago de Tota, Boyacá / Cultivable nitrifying bacteria of the limnetic zone of Tota lake, Boyacá, Colombia

RESUMEN Las actividades de producción piscícola en el Lago de Tota, Boyacá aumentan las concentraciones de amonio y de nitrato, nutrientes que están acelerando los procesos de eutrofización. Entre las comunidades microbianas que regulan la entrada de nitrógeno alóctono figuran las bacterias nitrificantes y la determinación de su abundancia en los ecosistemas es una medida de bioindicación de contaminación. El objetivo del estudio fue cuantificar y caracterizar bioquímicamente las bacterias nitrificantes cultivables de la zona limnética del lago. Para medir la abundancia, se usó la técnica de número más probable (NMP). Las muestras fueron tomadas en los sectores Lago Chico y Lago Grande, en zonas limnéticas, con actividad piscícola y sin intervención. Se midieron variables físicas y químicas in situ y se determinó la concentración de nutrientes en el laboratorio. Las mayores cuantificaciones de bacterias nitrificantes, se registraron en el periodo de baja precipitación y en el área de influencia de piscicultura. El grupo de bacterias oxidantes de amonio (BOA) y oxidantes de nitritos (BON) fue menor en la zona central de lago Grande respecto a zonas de piscifactorías de Hato Laguna y El Túnel. Se obtuvieron 14 aislamientos de bacterias nitrificantes, identificando los géneros Nitrosomonas spp. y Nitrobacter spp. Los cambios en la abundancia de BOA, se relacionaron con la alcalinidad, mientras que los valores de BON, se correlacionaron con la conductividad eléctrica y el nitrógeno inorgánico disuelto. Una mayor abundancia de bacterias nitrificantes, se registró en las zonas limnéticas del lago, afectadas por la actividad piscícola, asociado al aumento de nutrientes disuelto en la columna de agua.

ABSTRACT Fish production activities in Lake Tota, Boyacá are increasing concentrations of ammonium and nitrate, nutrients that are accelerating eutrophication processes. Some of the microbial communities that regulate the entry of allochthonous nitrogen are nitrifying bacteria, and the determination of their abundance in ecosystems is a measure of pollution bioindication. The objective of the study was to quantify and biochemically characterize the cultivable nitrifying bacteria of the limnetic zone of Lake Tota. The most probable number technique (MPN) was used to measure abundance. The samples were taken in the Lago Chico and Lago Grande sectors, in limnetic areas with fish activity and without intervention. Physical and chemical variables were measured in situ and the concentration of nutrients in the laboratory was determined. The highest quantifications of nitrifying bacteria were recorded in the area of influence of fish farming. The group of ammonium oxidizing bacteria (BOA) and nitrite oxidants (BON) was smaller in the central area of Lago Grande compared to fish farms in Hato Laguna and El Túnel. 14 isolates of nitrifying bacteria were obtained, genera Nitrosomonas spp. and Nitrobacter spp. Changes in BOA abundance were related to alkalinity, while BON values correlated with electrical conductivity and dissolved inorganic nitrogen. A greater abundance of nitrifying bacteria was recorded in the lake's limnetic areas affected by fish farming activity, associated with the increase in nutrients dissolved in the water column.