A Focus on Aflatoxin in Feedstuffs: New Developments in Analysis and Detection, Feed Composition Affecting Toxin Contamination, and Interdisciplinary Approaches to Mitigate It

Aflatoxins are mold-synthetized secondary metabolites that are capable of causing disease and death in humans and other animals. Aflatoxins hold a prominent place in the discussion on feed safety as are the only mycotoxins with the regulatory framework. Feed ingredients and composition inevitably affect the susceptibility of feed to fungal and toxin contamination. To verify that legal thresholds are being complied, avoiding delivering contaminated feed to animals, and obtain correct prevalence data, analytical methods must be developed which are apt for application on a complex matrix such as animal feed. These methods should include simple screening assays and high-end confirmatory ones. Laboratories without expensive equipment can and should be able to implement methods and to analyze and detect aflatoxins. Aflatoxin contamination is a complex issue that should be assessed interdisciplinarily and farm-to-fork models should be integrated into vigilance. In this chapter, we have devoted some lines to each of the aspects mentioned above focusing on feed aflatoxin contamination

Insights into the Interaction of Milk and Dairy Proteins with Aflatoxin M1

In this chapter, up-to-date data regarding the nature of protein interaction with a contaminant such as aflatoxin M1 (AFM1) is detailed. Considering that AFM1 is a relevant toxin present in milk and dairy products, it is important to understand such interaction. With this in mind, some specific features of protein chemistry and structure are discussed. AFM1 presence and origin in milk and the latest approaches in AFM1 chemical analysis with special attention to sample preparation techniques to eliminate milk protein–AFM1 interaction will also be addressed. Emphasis will be given to the interaction of AFM1 with whey proteins of which little has been described. In order to represent such interactions, recent scientific evidence is briefly discussed which describes the outcome, stability, and distribution of the toxin among the fractions, especially during the cheese-making process. An in silico model is presented in which some details of the AFM1-protein interactions are described. Finally, two technological applications of proteins in the food industry which are affected negatively by AFM1 contamination, are provided as an example of how the contaminant has a deep relationship in protein behaviour

A Focus on Aflatoxins in Feedstuffs: Levels of Contamination, Prevalence, Control Strategies, and Impacts on Animal Health

Aflatoxins are mold-synthetized secondary metabolites that are ubiquitously present in agricultural commodities, such as cereals which in turn are substantial part of feed formulation. These toxins are capable of causing disease, exert severe toxic effects, and even death in humans and other animals. Aflatoxins are the only mycotoxins with the regulatory framework, hence we present the legal threshold uphold till now by international and regional control organizations. Additionally, herein we discuss worldwide prevalence of aflatoxins in feeds to demonstrate a global issue and major risks involved in toxin contamination. Furthermore, we present recent data regarding negative effects usually presented by food-producing and companionship animals when ingested. Also, we discuss briefly practical approaches to mitigate aflatoxin burden during feed processing focusing in Good Manufacturing Practice (GMP) and hazard analysis critical control point (HACCP) and we include novel approaches reported in literature to decontaminate feed-containing aflatoxins. Finally, we cite the literature so far published describing the effects of changing climate on aflatoxin production and contamination

Tetracyclines in Food and Feedingstuffs: From Regulation to Analytical Methods, Bacterial Resistance, and Environmental and Health Implications

Antibiotics are widely used as growth promoters in animal husbandry; among them, the tetracyclines are a chemical group of relevance, due to their wide use in agriculture, surpassing in quantities applied almost every other antibiotic family. Seeing the considerable amounts of tetracyclines used worldwide, monitoring of these antibiotics is paramount. Advances must be made in the analysis of antibiotics to assess correct usage and dosage of tetracyclines in food and feedstuffs and possible residues in pertinent environmental samples. The tetracyclines are still considered a clinically relevant group of antibiotics, though dissemination of tolerance and resistance determinants have limited their use. This review focuses on four different aspects: (i) tetracyclines, usage, dosages, and regulatory issues that govern their food-related application, with particular attention to the prohibitions and restrictions that several countries have enforced in recent years by agencies from both the United States and the European Union, (ii) analytical methods for tetracyclines, determination, and residues thereof in feedstuffs and related matrices with an emphasis on the most relevant and novel techniques, including both screening and confirmatory methods, (iii) tetracycline resistance and tetracycline-resistant bacteria in feedstuff, and (iv) environmental and health risks accompanying the use of tetracyclines in animal nutrition. In the last two cases, we discuss the more relevant undesirable effects that tetracyclines exert over bacterial communities and nontarget species including unwanted effects in farmers.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro de Investigación en Nutrición Animal (CINA)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Centro de Investigación en Enfermedades Tropicales (CIET

Selenium Concentrations in Serum and its Outputs in Milk and Urine from Grazing Jersey Cow Herds Found in Two Dairy Production Regions from Costa Rica

Objective: The study aimed to determine the concentration of selenium (Se) and glutathione peroxidase (GSH-Px) in serum and the Se concentration in milk and urine in grazing Jersey cows in two dairy producing areas of Costa Rica. Methodology: The study was conducted on commercial dairy herds in the highlands of Cartago (≈2250 m of altitude) and Zarcero (≈1750 m of altitude). Cartago cow herds were intensively grazing kikuyu grass (Kikuyuocloa clandestina) and Zarcero cow herds were grazing star grass (Cynodon nlemfuensis). Daily supplementation in both areas consisted of concentrate (16% CP, 1.81 Mcal NEL) according to milk yield (1 kg concentrate: 3 kg of milk). Blood samples were taken from the coccygeal vessels, milk samples were collected individually during milking from the milk yield meter container and urine was obtained using rubbing stimulation technique. From Cartago area, a total of 102, 139 and 87 samples of blood, milk and urine respectively were collected and analyzed. From Zarcero region 66, 84 and 43 samples in the same order were collected and analyzed. Results: Atomic absorption spectrophotometry was used to determine Se concentration. A total of 85 samples from two farms in each region were tested to determine GSH-Px using a glutathione peroxidase activity colorimetric assay kit. The soil was tested in each farm using a soil auger to obtain 20 subsamples per sample, those subsamples were collected drilling the ground surface to a depth of 10 cm and then mixed to generate a composited sample which was analyzed for Se using atomic absorption spectrophotometry. Average serum, milk and urine Se concentration for cows from Cartago and Zarcero were 44.13 (SD = 27.68), 30.94 (SD = 20.13), 78.37 (SD = 60.14) μg Se L–1 and 19.19 (SD = 10.59), 21.82 (SD = 19.07), 14.72 (SD = 6.50) μg Se L–1, respectively. The average GSH-Px concentration in serum was 73.74 and 33.82 for Cartago and Zarcero cows, respectively. Conclusion: High concentrations of selenium in urine in some of the farms and low concentrations of GSH-Px in serum in most of the cows could imply a poor utilization of this mineral, leading to deficiencies to meet metabolic requirements and therefore to associated economic losses.Universidad de Costa Rica/[739-B3-120]/UCR/Costa RicaUCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de ZootecniaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro de Investigación en Nutrición Animal (CINA

Composition, Chemical Fingerprinting and Antimicrobial Assessment of Costa Rican Cultivated Guavas (Psidium friedrichsthalianum (O. Berg) Nied. and Psidium guajava L.) Essential Oils from Leaves and Fruits

The essential oil of two related tree species, P. friedrichsthalianum and P. guajava, where obtained. A total of six different oil samples were recovered including leaves in dry/rainy season and fruits of both plant species. Oil yields ranged between 0.128% (P. friedrichsthalianum leaves during dry season)-0.743% (P.guajava leaves during rainy season). All extracts were subjected to a GC/MS analysis using, during the chromatographic separation, a polyethylene glycol column. In general terms, we recognized three independent biosynthetic routes i. aromatic compounds ii. Terpenes and iii.Fatty acids derivatives. Several compound were found to be preserved in several of the oils such as 2,4-di-tert-butylphenol, α-terpineol and neointermedeol whereas Costa Rican guava fruit exhibit unique compounds such as 2H-pyran-2,6-(3H)-dione. Terpenes and fatty acids are among the most variable (p0.1%) and trace compounds. In addition, we evaluated the antimicrobial activity of these essential oils against common foodborne and food-spoilage related bacteria. The rainy season P. guajava leafs’ presented the highest antimicrobial activity against all the bacteria strains tested, with inhibition zones ranging from 31 to 52 mm. This study will help understand volatile composition of a fruit producing plant native from this geographic area and hints toward possible applications.Universidad de Costa Rica/[809-B6-257]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigaciones en Productos Naturales (CIPRONA

Microbiological Safety and Presence of Major Mycotoxins in Animal Feed for Laboratory Animals in a Developing Country: The Case of Costa Rica

Safety and quality of compound feed for experimental animals in Costa Rica is unknown. Some contaminants, such as Salmonella spp. and mycotoxins, could elicit confounding effects in laboratory animals used for biomedical research. In this study, different batches of extruded animal feed, intended for laboratory rodents in Costa Rica, were analyzed to determine mycotoxin and microbiological contamination (i.e., Salmonella spp., Escherichia coli, total coliform bacteria, and total yeast and molds enumeration). Two methods for Salmonella decontamination (UV light and thermal treatment) were assessed. Only n = 2 of the samples were negative (representing 12.50%) for the 26 mycotoxins tested. Enniatins and fumonisins were among the most frequent toxins found (with n = 4+ hits), but the level of contamination and the type of mycotoxins depended on the supplier. None of the indicator microorganisms, nor Salmonella, were found in any of the tested batches, and no mold contamination, nor Salmonella growth, occurs during storage (i.e., 2–6 months under laboratory conditions). However, mycotoxins, such as enniatins and fumonisins tend to decrease after the fourth month of storage, and Salmonella exhibited a lifespan of 64 days at 17 °C even in the presence of UV light. The D-values for Salmonella were between 65.58 ± 2.95 (65 °C) and 6.21 ± 0.11 (80 °C) min, and the thermal destruction time (z-value) was calculated at 15.62 °C. Results from this study suggest that laboratory rodents may be at risk of contamination from animal feed that could significantly affect the outcomes of biomedical experiments. Thus, improved quality controls and handling protocols for the product are suggested

Bioavailability of in-feed tetracyclines is influenced to a greater extent by crude protein rather than calcium

Feed is a common vehicle for tetracycline administration in animal farming. However, veterinarians and farmers often overlook that common feed components, such as proteins and calcium, may interact with these drugs and thereby alter their properties. In this study, we aimed to quantify the effect of crude protein and calcium on the bioavailability of 14 first-, second-, and third-generation tetracyclines, tetracycline epimers that may arise during storage, and other tetracycline derivatives in 84 feedstuffs for shrimp, swine, tilapia, and poultry marketed in Costa Rica. To this end, crude protein was quantified with a Kjeldahl method, calcium was determined by flame atomic spectroscopy (FAAS), and tetracyclines were detected by high-performance liquid chromatography (HPLC) with fluorescence detection (FLD) and with two different whole-cell biosensors to discriminate matrix-bound, inactive tetracyclines from free, active fractions. Tilapia feed contained the highest amounts of HPLC-detectable tetracyclines (119–8365 mg kg−1). Poultry (78–438 mg kg−1) and swine feed (41–1076 mg kg−1) were characterized by intermediate concentrations, while shrimp feed showed the lowest amounts of these drugs (21–50 mg kg−1). Ten samples contained unauthorized antibiotics, including doxycycline, and another three had 4-epimers of tetracyclines, indicating degradation during prolonged storage. Biological detection of tetracyclines was inversely related to both feed crude protein (r2 = 0.58–0.75) and calcium content (r2 = 0.54–0.63). Moreover, only 12–55% of the concentrations determined by HPLC were appraised by the biosensors. Shrimp feed, followed by tilapia feed, showed the highest crude protein (14.5–52.2g 100 g−1) and calcium (0.89–5.90 mg kg−1) concentrations and, as predicted, the lowest bioavailable fractions of tetracyclines (12–40%). Finally, we provide equations that predict bioavailability as a function of crude protein, calcium, and tetracycline concentrations in feed. Our data reveals medication abnormalities in commercial feeds and provide novel biological information for several tetracyclines.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Centro de Investigación en Enfermedades Tropicales (CIET)UCR::Vicerrectoría de Docencia::Salud::Facultad de Microbiologí

Total starch in animal feeds and silages based on the chromatographic determination of glucose

Starch is an important nutrient in animal feed, and so its analysis is of considerable concern as it is one of the most relevant energy containing fractions. Method AOAC 996.11 was modified to exchange the enzymometric and colorimetric step full approach to a simpler HPLC amine-based column one. The method was optimized and validated for its application in animal feeds and silages. • We demonstrated that the method could be used for quality control for animal feeds and silages • We modified the final incubation time, the initial sample mass, the quantity of enzyme added and buffered, to pH 6.2, the medium to which α-amylase is added. • We applied a chromatographic analysis of the glucose that resulted from starch enzymatic hydrolysis, via a refractive index detector and amine-based chromatographic column. Method name: Starch in animal feed and silage, Keywords: Starch, Glucose, Enzymatic hydrolysis, Liquid chromatography, Refractive index detector, Feed, Silag