The usage of antibiotics has been, and remains, a topic of utmost importance; on the one hand, for animal breeders, and on the other hand, for food safety. Although many countries have established strict rules for using antibiotics in animal husbandry for the food industry, their misuse and irregularities in compliance with withdrawal periods are still identified. In addition to animal-origin foods that may cause antibiotic residue problems, more and more non-animal-origin foods with this type of non-compliance are identified. In this context, we aim to summarize the available information regarding the presence of antibiotic residues in food products, obtained in various parts of the world, as well as the impact of consumption of food with antibiotic residues on consumer health. We also aim to present the methods of analysis that are currently used to determine antibiotic residues in food, as well as methods that are characterized by the speed of obtaining results or by the possibility of identifying very small amounts of residues.

Chicken egg yolk antibody, also known as immunoglobulin Y (IgY), is the predominant class of serum immunoglobulin in birds. IgY has many advantages over mammalian antibodies, such as enhanced immunogenicity conserved mammalian proteins exhibited in birds due to their phylogenetic distance, non-invasive rapid, and economical collection system. However, there are limited studies about IgY production against Toxoplasma, which is a worldwide veterinary and public health problem. In this study, the production of specific IgY antibodies against the surface antigen 1 (SAG1) protein of Toxoplasma gondii and the determination of antibody activity via the enzyme-linked immunosorbent assay (ELISA) method were conducted. According to ELISA, Western blot, and NanoDrop results, specific and higher amounts of IgY antibody against SAG1 were obtained with this study. Considering the advantages of IgY and importance of SAG1 for the diagnosis of toxoplasmosis, it is expected that anti-SAG1 IgY will play an increasing role and gain commercial value in research, diagnostics, and immunotherapy against toxoplasmosis in the future.

Egg yolk constitutes a relevant alternative source of antibodies. It presents some advantages over mammalian serum immunoglobulins regarding productivity, animal welfare and specificity. The main immunoglobulin present in avian blood (IgY) is transmitted to their offspring and accumulates in egg yolks, which enables the non-invasive harvesting of high amounts of antibodies. Moreover, due to structural differences and phylogenetic distance, IgY is more suitable for diagnostic purposes than mammalian antibodies, since it does not react with certain components of the human immune system and displays greater avidity for mammalian conserved proteins. IgY has been extensively used in health researches, as both therapeutic and diagnostic tool. This article aims to review its applications in both human and veterinary health.Copyright © 2019 Elsevier B.V. All rights reserved.

cDNA clones encoding the variable and constant regions of chicken immunoglobulin (Ig) gamma-chains were obtained from spleen cDNA libraries. Southern blots of kidney DNA show that the variable region sequences of eight cDNA clones reveal the same set of bands corresponding to approximately 30 cross-hybridizing VH genes of one subgroup. Since the VH clones were randomly selected, it is likely that the bulk of chicken H-chains are encoded by a single VH subgroup. Nucleotide sequence determinations of two cDNA clones reveal VH, D, JH and the constant region. The VH segments are closely related to each other (83% homology) as expected for VH or the same subgroup. The JHs are 15 residues long and differ by one amino acid. The Ds differ markedly in sequence (20% homology) and size (10 and 20 residues). These findings strongly indicate multiple (at least two) D genes which by a combinatorial joining mechanism diversify the H-chains, a mechanism which is not operative in the chicken L-chain locus. The most notable among the chicken Igs is the so-called 7S IgG because its H-chain differs in many important aspects from any mammalian IgG. The sequence of the C gamma cDNA reported here resolves this issue. The chicken C gamma is 426 residues long with four CH domains (unlike mammalian C gamma which has three CH domains) and it shows 25% homology to the chicken C mu. The chicken C gamma is most related to the mammalian C epsilon in length, the presence of four CH domains and the distribution of cysteines in the CH1 and CH2 domains. We propose that the unique chicken C gamma is the ancestor of the mammalian C epsilon and C gamma subclasses, and discuss the evolution of the H-chain locus from that of chicken with presumably three genes (mu, gamma, alpha) to the mammalian loci with 8-10 H-chain genes.

The generation and use of avian antibodies is of increasing interest in a wide variety of applications within the life sciences. Due to their phylogenetic distance, mechanisms of immune diversification and the way in which they deposit IgY immunoglobulin in the egg yolk, chickens provide a number of advantages compared to mammals as hosts for immunization. These advantages include: the one-step purification of antibodies from egg yolk in large amounts facilitates having a virtually continuous supply; the epitope spectrum of avian antibodies potentially grants access to novel specificities; the broad absence of cross-reactivity with mammalian epitopes avoids assay interference and improves the performance of immunological techniques. The polyclonal nature of IgY antibodies has limited their use since avian hybridoma techniques are not well established. Recombinant IgY, however, can be generated from mammalian monoclonal antibodies which makes it possible to further exploit the advantageous properties of the IgY scaffold. Moreover, cloning and selecting the immune repertoire from avian organisms is highly efficient, yielding antigen-specific antibody fragments. The recombinant approach is well suited to circumvent any limitations of polyclonal antibodies. This review presents comprehensive information on the generation, purification, modification and applications of polyclonal and monoclonal IgY antibodies.Copyright © 2012 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

IgY is the functional equivalent of IgG in birds, reptiles and amphibia, but many aspects of its biology are poorly understood. Recent studies have increased awareness of the genetics and functions of this molecule, and have revealed its position as the ancestor of the uniquely mammalian antibodies IgG and IgE. Here, Greg Warr, Kathy Magor and David Higgins review current knowledge of IgY structure, function and expression in the context of the evolutionary role of this primitive immunoglobulin.

Rabies virus was used as the antigen to immunize laying chickens. Anti-rabies virus immunoglobulin Y(IgY) was isolated from yolks of the eggs laid by these chickens using a two-step salt precipitation and one-step gel filtration protocol. The purified IgY was reduced with dithiothreitol, and heavy chains (HC) and light chains (LC) were obtained. In addition, the purified IgY was digested with pepsin and the fragment with specific antigen binding properties (Fab) was produced. Using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOFMS), the average molecular weights of IgY, HC, LC, and Fab were determined as 167 250, 65 105, 18 660, and 45,359 Da, respectively. IgY has two structural differences compared with mammalian IgGs. First, the molecular weight of the heavy chain of IgY is larger than that of its mammalian counterpart, while the molecular weight of the light chain of IgY is smaller. Second, upon pepsin digestion, anti-rabies virus IgY is degraded into Fab, in contrast to mammalian IgG, which has been reported to be degraded into F(ab')(2) under the same conditions.Copyright 2001 John Wiley & Sons, Ltd.

The production of antibodies (Abs) in chickens and the extraction of specific Abs from egg yolk (IgY Abs) are increasingly attracting the interest of the scientific community, as demonstrated by the significant growth of the IgY literature. This review offers detailed and comprehensive information about IgY-technology, including: a) possibilities for hen keeping in accordance with the Three Rs principles; b) new insights into the IgY transfer mechanism from blood to yolk as a biological basis for the technology; c) the comparative characteristics of IgY Abs and IgG Abs; d) the high efficacy of the technique, in view of the extraordinary amount of IgY Ab produced by one hen in one year (between 20 g and 40 g IgY in total); e) comparisons between the efficacies of IgY Abs and IgG Abs (rabbit, sheep, mouse) in several immunological assays; f) immunisation protocols, as well as the most commonly used IgY-extraction procedures; g) new possibilities for application in human and veterinary medicine, including strategies for the treatment of Helicobacter pylori infection or fatal intestinal diseases in children, particularly in poor countries, for reducing the use of antibiotics, and, in Asia and South America, for producing Abs against snake, spider and scorpion venoms; and h) the use of IgY Abs in various fields of research, also taking into consideration recent developments in South America (particularly Argentina and Cuba) and in Asia.

Oral administration of chicken egg yolk immunoglobulin (IgY) has attracted considerable attention as a means of controlling infectious diseases of bacterial and viral origin. Oral administration of IgY possesses many advantages compared with mammalian IgG including cost-effectiveness, convenience and high yield. This review presents an overview of the potential to use IgY immunotherapy for the prevention and treatment of terrestrial and aquatic animal diseases and speculates on the future of IgY technology. Included are a review of the potential application of IgY for the treatment of livestock diseases such as mastitis and diarrhea, poultry diseases such as Salmonella, Campylobacteriosis, infectious bursal disease and Newcastle disease, as well as aquatic diseases like shrimp white spot syndrome virus, Yersina ruckeri and Edwardsiella tarda. Some potential obstacles to the adoption of IgY technology are also discussed.Copyright © 2011 Elsevier Inc. All rights reserved.

Oral administration of specific antibodies is an attractive approach to establish protective immunity against gastrointestinal pathogens in humans and animals. The increasing number of antibiotic-resistant bacteria emphasize the need to find alternatives to antibiotics. Immunotherapy can also be used against pathogens that are difficult to treat with traditional antibiotics. Laying hens are very good producers of specific antibodies. After immunization, the specific antibodies are transported to the egg yolk from which the antibodies then can be purified. A laying hen produces more than 20 g of yolk antibodies (IgY) per year. These antibodies also have biochemical properties that make them attractive for peroral immunotherapy: They neither activate mammalian complement nor interact with mammalian Fc receptors that could mediate inflammatory response in the gastrointestinal tract. Eggs are also normal dietary components and thus there is practically no risk of toxic side effects of IgY. Yolk antibodies have been shown in several studies to prevent bacterial and viral infections.

The adjuvant effects of various lipopeptides and recombinant chicken interferon gamma (IFN-gamma) on the humoral immune response of laying hens was investigated in four immunization studies. We used the lipopeptide Pam3Cys-Ser-(Lys)4 (PCSL), the conjugate P-Th1 consisting of the lipopeptide P3CS and the T-helper epitope Th1 (FISEAIIHVLHSRHPG), and the conjugate P-Th2 of the lipopeptide P3CSS and the T-helper epitope Th2, which corresponds to the peptide EWEFVNTPPLV, as adjuvants. Human serum albumin (HSA), recombinant bovine somatotropin (RBST), and human immunoglobulin G (IgG) served as antigens in the different experiments. All tested adjuvants enhanced the humoral immune response with various intensities. Chickens showed high antibody titers after the immunization with HSA even without adjuvant, but the adjuvant effects of PCSL and the combination of PCSL and recombinant chicken interferon-gamma (IFN-gamma) were much more pronounced using the antigens RBST and IgG. Especially after the third immunization, higher titers of antibodies were induced by the coadministration of P-Th1 and, to a greater extent, by the combination of PCSL and P-Th1 compared with the use of PCSL. Also, chickens that had received PCSL and P-Th2 showed the highest immune response, even after the second booster. The average concentrations of chicken immunoglobulin Y were significantly higher in 5-mo-old chickens (9.4 mg/mL serum and 10.1 mg/mL egg yolk) compared with 9-mo-old chickens (5.9 mg/mL serum and 5.1 mg/mL egg yolk). The specific serum antibody response was higher in the older chickens than in the younger chickens. Because chicken antibodies are likely to be used increasingly for diagnostic and therapy in the future, lipopeptides and recombinant chicken IFN-gamma may find many applications as adjuvants, thus contributing to the welfare of experimental animals.

Vibrio parahaemolyticus is a Gram-negative halophilic bacterium that is found in estuarine, marine and coastal environments. V. parahaemolyticus is the leading causal agent of human acute gastroenteritis following the consumption of raw, undercooked, or mishandled marine products. In rare cases, V parahaemolyticus causes wound infection, ear infection or septicaemia in individuals with pre-existing medical conditions. V parahaemolyticus has two hemolysins virulence factors that are thermostable direct hemolysin (tdh)-a poreforming protein that contributes to the invasiveness of the bacterium in humans, and TDH related hemolysin (trh), which plays a similar role as tdh in the disease pathogenesis. In addition, the bacterium is also encodes for adhesions and type III secretion systems (T3SS1 and T3SS2) to ensure its survival in the environment. This review aims at discussing the V parahaemolyticus growth and characteristics, pathogenesis, prevalence and advances in molecular identification techniques.

Acute hepatopancreatic necrosis disease (AHPND), caused by a toxin-producing Vibrio parahaemolyticus strain, has become a serious threat to shrimp aquaculture. The need to regulate antibiotic use prompted the development of alternative ways to treat infections in aquaculture including the use of chicken egg yolk immunoglobulin (IgY) for passive immunization. This study evaluated the protective effect of IgY against AHPND infection in Litopenaeus vannamei (Boone). IgY was isolated from eggs laid by hens immunized with recombinant PirA-like (rPirA) and PirB-like (rPirB) toxins. Whole-egg powders having IgY specific to rPirA (anti-PirA-IgY) and rPirB (anti-PirB-IgY) and IgY from non-immunized hen (control-IgY) were mixed with basal diets at 20% concentrations and used to prefeed shrimp 3 days before the bacterial challenge test. Survival rates of the challenged shrimp fed the anti-PirA-IgY, anti-PirB-IgY and control-IgY diets were 86%, 14% and 0%, respectively. Only the feed containing anti-PirA-IgY protected shrimp against AHPND. Increasing the concentration of rPirA antigen to immunize hens and lowering the amount of egg powder in feeds to 10% consistently showed higher survival rates in shrimp fed with anti-PirA-IgY (87%) compared with the control (12%). These results confirm that addition of anti-PirA-IgY in feeds could be an effective prophylactic method against AHPND infection in shrimp.© 2019 John Wiley & Sons Ltd.

Since it first appeared in 1992, white spot syndrome virus (WSSV) has become the most threatening infectious agent in shrimp aquaculture. Within a decade, this pathogen has spread to all the main shrimp farming areas and has caused enormous economic losses amounting to more than seven billion US dollars. At present, biosecurity methods used to exclude pathogens in shrimp farms include disinfecting ponds and water, preventing the entrance of animals that may carry infectious agents and stocking ponds with specific pathogen-free post-larvae. The combination of these practices increases biosecurity in shrimp farming facilities and may contribute to reduce the risk of a WSSV outbreak. Although several control methods have shown some efficacy against WSSV under experimental conditions, no therapeutic products or strategies are available to effectively control WSSV in the field. Furthermore, differences in virulence and clinical outcome of WSSV infections have been reported. The sequencing and characterization of different strains of WSSV has begun to determine aspects of its biology, virulence and pathogenesis. Knowledge on these aspects is critical for developing effective control methods. The aim of this review is to present an update of the knowledge generated so far on different aspects of WSSV organization, morphogenesis, pathology and pathogenesis.

White spot syndrome virus (WSSV) is a major cause of mortality in shrimp lacking a true adaptive immune response. In this study, high activity egg yolk immunoglobulin (IgY) against WSSV for passive immunization of crustaceans was already prepared as crude and purified product, while an indirect enzyme-linked immunosorbent assay test was used for quality control of IgY activity. The effectiveness of IgY of intramuscular injection, oral administration, and immersion was investigated in crayfish (Procambius clarkiaii) against WSSV. The result showed that the groups treated with IgY from inactivated WSSV and DNA vaccine were, respectively, 20% and 80% mortality, which were significant difference in survival rates (P < 0.05) from the positive control groups. The groups in diet added 10% egg yolk powder and 1% IgY power showed 53.3% and 67.7% mortality, respectively, and the immersion showed 46.7% mortality, which have significantly different compared to the positive groups (P < 0.05). These results indicated passive immunization of specific IgY antibodies through intramuscular injection, oral administration, and immersion have effective to protect crayfish against WSSV. It is noteworthy that IgY as feed additive and immersion solution is useful and feasible methods in practical work. Thus, our results suggest that the passive immunization of crayfish with IgY against WSSV will have potential development to prevent and control WSSV in practical culture.

Although rarely, hemolytic uremic syndrome can be induced by Aeromonas. We report a case in a 40-year-old Spanish female produced by Aeromonas veronii bv. sobria and review the previous cases described in the literature. This is the 2nd case described in adults.

Aeromonas hydrophila is a motile gram-negative bacillus found in water sources that typically causes minor skin infections or gastroenteritis in humans. There are sporadic reports of cases of sepsis or necrotizing fasciitis caused by A. hydrophila but no other cases of severe infection secondary to trauma. The mortality rate of septic shock caused by A. hydrophila approaches 100%.Case report and review of pertinent literature.A patient recently seen at our institution illustrates the features of necrotizing fasciitis and sepsis caused by A. hydrophila after an open femur fracture. We describe the aggressive multi-modality treatment necessary to maximize the likelihood of survival.

Over the past decade, the genusAeromonashas undergone a number of significant changes of practical importance to clinical microbiologists and scientists alike. In parallel with the molecular revolution in microbiology, several new species have been identified on a phylogenetic basis, and the genome of the type species,A. hydrophilaATCC 7966, has been sequenced. In addition to established disease associations,Aeromonashas been shown to be a significant cause of infections associated with natural disasters (hurricanes, tsunamis, and earthquakes) and has been linked to emerging or new illnesses, including near-drowning events, prostatitis, and hemolytic-uremic syndrome. Despite these achievements, issues still remain regarding the role thatAeromonasplays in bacterial gastroenteritis, the extent to which species identification should be attempted in the clinical laboratory, and laboratory reporting of test results from contaminated body sites containing aeromonads. This article provides an extensive review of these topics, in addition to others, such as taxonomic issues, microbial pathogenicity, and antimicrobial resistance markers.