Early-life shedding and environmental presence of Mycobacterium avium ssp. paratuberculosis in Chilean dairy calves.

Neonatal dairy calves are highly susceptible to Mycobacterium avium ssp. paratuberculosis (MAP) infection, but data remain limited on early infection prevalence and transmission drivers. This study aimed to estimate the true prevalence of MAP infection and identify associated risk factors in Chilean dairy calves younger than 60 d of age.

Characterization and potential causes of a whiting event in the Mar Menor coastal lagoon (Mediterranean, SE Spain).

The Mar Menor is a hypersaline coastal lagoon in the southeast of Spain, which has experienced several eutrophication episodes in recent years. In 2022, an area of milky white turbid water appeared covering about 10 % of its surface, and it has been there ever since. A comprehensive field research was set up to assess the origin of this possible whiting event, including identification of continental water inputs, satellite imagery and analyses of physico-chemical properties of the water column, sediment, and the planktonic and benthic communities.

An assessment of the Chilean COVID-19 surveillance program through the comparison between reported and true SARS-CoV-2 infection prevalence: A case study of three urban centers in southern Chile.

Objectives: Estimate the detection limits of the COVID-19 surveillance system (SS) in Chile, by estimating the SARS-CoV-2 true prevalence (TP) and the reported official positivity prevalence (OPP) gap.

Study Design: Randomized cross-sectional.

Methods: Two sampling campaigns (SC) were conducted (October-November 2020 and December 2020-January 2021) in the cities of Temuco, Valdivia, and Osorno.

The Chilean COVID-19 Genomics Network Biorepository: A Resource for Multi-Omics Studies of COVID-19 and Long COVID in a Latin American Population.

Although a lack of diversity in genetic studies is an acknowledged obstacle for personalized medicine and precision public health, Latin American populations remain particularly understudied despite their heterogeneity and mixed ancestry. This gap extends to COVID-19 despite its variability in susceptibility and clinical course, where ethnic background appears to influence disease severity, with non-Europeans facing higher hospitalization rates. In addition, access to high-quality samples and data is a critical issue for personalized and precision medicine, and it has become clear that the solution lies in biobanks.

Performance estimation of two in-house ELISA assays for COVID-19 surveillance through the combined detection of anti-SARS-CoV-2 IgA, IgM, and IgG immunoglobulin isotypes.

The main objective of this study was to estimate the performance, under local epidemiological conditions, of two in-house ELISA assays for the combined detection of anti-SARS-CoV-2 IgA, IgM, and IgG immunoglobulins. A total of 94 serum samples were used for the assessment, where 44 corresponded to sera collected before the pandemic (free of SARS-CoV-2 antibodies), and 50 sera were collected from confirmed COVID-19 patients admitted to the main public hospital in the city of Valdivia, southern Chile. The Nucleocapsid (Np) and the receptor-binding domain (RBD) proteins were separately used as antigens (Np and RBD ELISA, respectively) to assess their diagnostic performance.

Association between the severity of histopathological lesions and subspecies (MAP) molecular diversity in cattle in southern Chile.

The objective was to evaluate the association between the severity of histopathological lesions caused by subspecies (MAP) infection and the molecular diversity of this pathogen. Blood, ileum, and mesenteric lymph node samples were collected at slaughter, from 1,352 adult cattle [source population 1 (SP1)]. In addition, 42 dairy herds ( = 4,963 cows) were followed for 2 years, and samples from compatible clinical cases [source population 2 (SP2)] were collected.

Attempted Control of Paratuberculosis in Dairy Calves by Only Changing the Quality of Milk Fed to Calves.

One of the important routes of subsp. (MAP) transmission in dairy calves is milk. The aim of the present study was to assess the efficacy of milk treatments to prevent MAP infection transmission to calves.

Longitudinal Study of Total and Pathogenic (+ and/or +) in Two Natural Extraction Areas of in Southern Chile.

is the leading cause of seafood-associated bacterial gastroenteritis worldwide. Although different studies have focused on its pattern of variation over time, knowledge about the environmental factors driving the dynamics of this pathogen, within the Chilean territory, is still lacking. This study determined the prevalence of total and pathogenic strains ( and/or genes) in mussels () collected from two natural growing areas between 2017 and 2018, using selective agar and PCR analysis.

Bayesian latent class estimation of sensitivity and specificity parameters of the PMS-PCR test for the diagnosis of cattle sub-clinically infected with Mycobacterium avium subsp. paratuberculosis.

The objective of this study was to estimate the performance of the peptide magnetic separation PCR test (PMS-PCR) for the diagnosis of Mycobacterium avium subsp. paratuberculosis (MAP) in sub-clinically infected dairy cattle. Twenty-one herds were randomly selected from a source population of 131 commercial dairy herds with a known history of MAP infection, located in the De Los Rios and De Los Lagos regions, in southern Chile.

Herd level risk factors for Mycobacterium avium subsp. paratuberculosis infection and clinical incidence in dairy herds in Chile.

The study objective was to identify risk factors associated to: i) the infection by Mycobacterium avium subsp. paratuberculosis (MAP), and ii) paratuberculosis clinical incidence in Chilean dairy herds. A random sample of forty herds with previous history of MAP infection was selected.

Control of paratuberculosis: who, why and how. A review of 48 countries.

Paratuberculosis, a chronic disease affecting ruminant livestock, is caused by Mycobacterium avium subsp. paratuberculosis (MAP). It has direct and indirect economic costs, impacts animal welfare and arouses public health concerns.

Low accuracy of Bayesian latent class analysis for estimation of herd-level true prevalence under certain disease characteristics-An analysis using simulated data.

Estimation of the true prevalence of infected individuals involves the application of a diagnostic test to a population and adjusting according to test performance, sensitivity and specificity. Bayesian latent class analysis for the estimation of herd and animal-level true prevalence, has become increasingly used in veterinary epidemiology and is particularly useful in incorporating uncertainty and variability into analyses in a flexible framework. However, the approach has not yet been evaluated using simulated data where the true prevalence is known.

Within-herd prevalence and clinical incidence distributions of Mycobacterium avium subspecies paratuberculosis infection on dairy herds in Chile.

This study aimed to estimate the distributions of the within-herd true prevalence (TP) and the annual clinical incidence proportion (CIp) of Mycobacterium avium subsp. paratuberculosis (MAP) infection in dairy cattle herds in Chile. Forty two commercial herds with antecedents of MAP infection were randomly selected to participate in the study.

Prevalence of tuberculosis, brucellosis and trypanosomiasis in cattle in Tanzania: a systematic review and meta-analysis.

A meta-analysis was performed to derive prevalence estimates for Brucella spp., Mycobacterium spp. and Trypanosoma spp.

Within- and between-herd prevalence variation of Mycobacterium avium subsp. paratuberculosis infection among control programme herds in Denmark (2011-2013).

This study aimed to estimate the between- (HTP) and within- (TP) herd true prevalence distribution of Mycobacterium avium subsp. paratuberculosis (MAP) infection in dairy cattle herds participating in the Danish MAP control programme. All herds enrolled in the programme between 2011 and 2013 were included in the analysis, and one annual milk-ELISA test of all lactating cows present in such herds was considered.

Estimation of flock/herd-level true Mycobacterium avium subspecies paratuberculosis prevalence on sheep, beef cattle and deer farms in New Zealand using a novel Bayesian model.

The study aimed to estimate the national- and island-level flock/herd true prevalence (HTP) of Mycobacterium avium subsp. paratuberculosis (MAP) infection in pastoral farmed sheep, beef cattle and deer in New Zealand. A random sample of 238 single- or multi-species farms was selected from a postal surveyed population of 1940 farms.

Molecular epidemiology of Mycobacterium avium subsp. paratuberculosis isolated from sheep, cattle and deer on New Zealand pastoral farms.

The present study aimed to describe the molecular diversity of Mycobacterium avium subsp. paratuberculosis (MAP) isolates obtained from sheep, cattle (beef and dairy) and deer farms in New Zealand. A total of 206 independent MAP isolates (15 beef cattle, 89 dairy cattle, 35 deer, 67 sheep) were sourced from 172 species-mobs (15 beef cattle, 66 dairy cattle, 31 deer, 60 sheep).

Biocatalytic behaviour of immobilized Rhizopus oryzae lipase in the 1,3-selective ethanolysis of sunflower oil to obtain a biofuel similar to biodiesel.

A new biofuel similar to biodiesel was obtained in the 1,3-selective transesterification reaction of sunflower oil with ethanol using as biocatalyst a Rhizopus oryzae lipase (ROL) immobilized on Sepiolite, an inorganic support. The studied lipase was a low cost powdered enzyme preparation, Biolipase-R, from Biocon-Spain, a multipurpose additive used in food industry. In this respect, it is developed a study to optimize the immobilization procedure of these lipases on Sepiolite.

Selective ethanolysis of sunflower oil with Lipozyme RM IM, an immobilized Rhizomucor miehei lipase, to obtain a biodiesel-like biofuel, which avoids glycerol production through the monoglyceride formation.

The obtaining of Ecodiesel, a biofuel applicable to diesel engines which keeps the glycerin as monoglyceride (MG), was achieved through a selective ethanolysis process of sunflower oil, by application of Lipozyme RM IM, a Rhizomucor miehei lipase immobilized on macroporous anion exchange resins. This biocatalyst that was already described in the synthesis of conventional biodiesel has also shown its efficiency in the present selective enzymatic process, after optimization of the influence of various reaction parameters. Thus, an adequate activity is obtained that is maintained throughout five successive reuses.

A novel low-cost method for Mycobacterium avium subsp. paratuberculosis DNA extraction from an automated broth culture system for real-time PCR analysis.

PCR is a highly accurate technique for confirming the presence of Mycobacterium avium subsp. paratuberculosis (Map) in broth culture. In this study, a simple, efficient, and low-cost method of harvesting DNA from Map cultured in liquid medium was developed.

New biofuel integrating glycerol into its composition through the use of covalent immobilized pig pancreatic lipase.

By using 1,3-specific Pig Pancreatic lipase (EC 3.1.1.

A comprehensive study of reaction parameters in the enzymatic production of novel biofuels integrating glycerol into their composition.

A comprehensive study of critical parameters in the pig pancreatic lipase (PPL) catalysed transesterification of sunflower oil to novel biofuels integrating glycerol into their composition is reported. The influence of oil/alcohol ratio, temperature, quantity of enzyme and water added and pH have been investigated. The enzymatic activity of PPL was found to be greatly influenced by the pH, reaching notable activities at high pH values (10-12), in contrast to other lipases.

Simulation of an early warning system using sentinel birds to detect a change of a low pathogenic avian influenza virus (LPAIV) to high pathogenic avian influenza virus (HPAIV).

The placement of sentinel birds in a commercial poultry flock infected with low pathogenic avian influenza virus (LPAIV) may be an effective way of detecting subsequent change in the isolate to a high pathogenic avian influenza virus (HPAIV). Data collected from the 2002 Chilean HPAIV outbreak, along with information from a literature review of laboratory studies involving A/chicken/Chile/176822/02 (H7N3/LP) and A/chicken/Chile/184240-1/02 (H7N3/HP) viruses, were used to construct a computer simulation model. Mortality rates of the original LPAIV-infected population and the sentinel population were compared to detect the presence of HPAIV.