Effects of an active immunization on the immune response of laying Japanese quail (Coturnix coturnix japonica) fed with or without genetically modified Bacillus thuringiensis-maize

Fate of transgenic soybean DNA and immune response of broilers fed genetically modified DP-3Ø5423-1 soybean

Increased use of genetically modified (GM) plants in the food and feed industry has raised several concerns about the presence of unwanted genes in the food chain and potential associated health risks. In recent years, several studies have compared the nutrient contents of GM crops to conventional counterparts, and some have also tracked the fate of novel DNA fragments and proteins in the gastrointestinal (GIT) and their presence in several tissues. This study was conducted to investigate the fate of transgenic PHP19340A DNA fragment containing gm-fad2-1 (Soybean Event DP-3Ø5423-1) gene in digestive tract contents, blood, internal organs, and muscle tissues. The effects of feeding DP-3Ø5423-1 full-fat soybean meal (FFSBM) to broiler chickens on immune response and blood profiles were also evaluated on d 35. Day-old Ross 308 birds (n = 480) were randomly allocated to 24 floor pens in a 2 × 2 factorial arrangement with diet and gender as main factors. Birds were fed diets containing 20% of either DP-3Ø5423-1 or non-GM FFSBM for 35 d. Data were subjected to a 2-way ANOVA using the GLM procedure of JMP (Pro13). Based on PCR analysis, transgenic PHP19340A DNA fragment containing gm-fad2-1 gene was degraded throughout the digestive system to reach undetectable level in the cecal digesta. Moreover, there was no transgenic gene translocation to blood, organs, or muscle tissue. Feeding DP-3Ø5423-1 FFSBM to broilers had no effect on mRNA abundance of IL-1β, IL-2, IL-6, IL-12B, IL-17A, IFNγ, TNFα, and NF-κB in the spleen or on blood profile. In conclusion, these findings indicate that the examined transgenic fragment in DP-3Ø5423-1 FFSBM progressively degraded in the GIT and did not translocate into blood or tissues. Along with the immune response and blood profile findings, it can be assumed that DP-3Ø5423-1 soybean is safe and unlikely to pose any health risks to broilers or consumers.

Effects of genetically modified maize expressing Cry1Ab and EPSPS proteins on Japanese quail

A 49-d feeding study was conducted to evaluate the effects of the genetically modified (GM) maize strain C0030.3.5 on Japanese quails (Coturnix japonica) in terms of body performance and egg quality. Furthermore, the bodily fats of transgenic proteins in the Japanese quails were investigated. The results showed that the parameters body weight, hematology, serum chemistry, relative organ weight, and histopathological appearance were normal in male and female quails that consumed GM diets, and no differences could be attributed to the varying diets in regard to the laying performances or nutrient egg compositions between the groups. Furthermore, the transgenic Cry1Ab and EPSPS proteins were undetectable by Western blot in the blood, organ, fecal, and whole egg samples of quails fed a diet containing GM maize. The results obtained after 49 d suggested that consumption of C0030.3.5 transgenic feed did not adversely affect quail health or egg quality, and there was no evidence of transgenic protein translocation to the blood, tissues, feces, and eggs. Based on the different parameters assessed, C0030.3.5 transgenic maize is a safe food source for quails that does not differ in quality from non-GM maize.

Storage stability of anti-Salmonella Typhimurium immunoglobulin Y in immunized quail eggs stored at 4°C

Chicken egg yolk antibodies (IgYs) are extensively used for immunotherapy and immunodiagnostic purposes. Oral immunotherapy with specific IgYs is established as an efficient alternative to traditional antibiotic therapy in human and animals. Storing immunized eggs in refrigerator for a period of time could provide an inexpensive and convenient source of large volumes of specific antibodies. This study investigated the storage stability of anti- Salmonella Typhimurium IgYs in immunized quail egg yolks at 4°C over a period of more than 6 months. Salmonella spp.-free female Japanese quails (Coturnix coturnix japonica) were intramuscularly immunized whit Salmonella Typhimurium whole bacterial suspension (1.0×109 CFU/ml) emulsified with Freund adjuvants. During a period of 10 days after final immunization, eggs from each group were collected, randomized and stored at 4°C over a period of 200 days. Egg yolk IgY titer and specificity were determined using ELISA technique. S. Typhimurium specific IgY antibodies were detected in immunized quails and were significantly higher than the control group which confirmed the immunization procedure. Eggs from immunized quails can be collected and stored in 4°C refrigerator over a period of 2 months without any concern about the antibody degradation. After 80 days of storage at 4°C, although lower antibody titer was obtained in comparison to the first of study, anti-S. Typhimurium IgY level remained stable up to the 6 months without more significant declining. This trend will provide economical sources of polyclonal antibodies through reducing the number of immunized animals, management expenses and housing costs.

Production, purification, and evaluation of quail immunoglobulin Y against Salmonella typhimurium and Salmonella enteritidis

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Chicken egg yolk antibodies (IgYs) have been extensively used for immunotherapy and immunodiagnostic purposes.

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Production of specific IgYs against Salmonella typhimurium and Salmonella enteritidis were identified in Japanese quail.

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Formalin-inactivated Salmonella species induced higher immune responses over the heat-inactivated ones.

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Quail anti-Salmonella IgYs showed a high specificity to their corresponding immunogens.

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Quail can be considered as a valuable and inexpensive source for producing large scale of specific antibodies.

Salmonella species have been the major foodborne problems in food production systems, with Salmonella enterica serovars typhimurium (S. typhimurium) and enteritidis (S. enteritidis) being among the more common isolates. The oral administration of chicken egg yolk specific antibodies (IgYs) has been established as an efficient alternative for treatment and prevention of gastrointestinal pathogens including Salmonella. The present study was aimed to investigate the possible production of specific IgYs against Salmonella typhimurium and Salmonella enteritidis in quail egg yolks. Salmonella spp.-free female Japanese quails (Coturnix coturnix japonica) were intramuscularly immunized with formalin or heat-inactivated Salmonella immunogens (1.0 × 10⁹ CFU/mL) emulsified with Freund adjuvants. Egg yolk IgYs were purified using ammonium sulfate precipitation method. Anti-Salmonella IgYs titer and specificity were determined using enzyme-linked immunosorbent assay (ELISA) and western blot analysis. Salmonella specific IgYs detected in the immunized quails were significantly higher than those of the control group, which confirmed the immunization procedure. Specific IgYs against S. typhimurium and S. enteritidis were identified in both groups immunized with heat or formalin-inactivated immunogens. However, formalin-inactivated immunogens induced relatively higher immune responses over the heat-inactivated ones. Quail anti-Salmonella IgYs showed a high specificity to their corresponding immunogens, with moderate cross-reactivity to other members of Enterobacteriaceae family. Quail can be regarded as a valuable and inexpensive source for producing large-scale of specific antibodies that can be used for immunodiagnostic and immunotherapeutic purposes.

Health effects of feeding genetically modified (GM) crops to livestock animals: A review

A large share of genetically modified (GM) crops grown worldwide is processed into livestock feed. Feed safety of GM crops is primarily based on compositional equivalence with near-isogenic cultivars and experimental trials in rodents. However, feeding studies in target animals add to the evaluation of GM crops with respect to animal health. This review aimed to evaluate the possible health effects of feeding GM crops to livestock by reviewing scientific publications on experimental studies in ruminants, pigs, and poultry in which at least one of the following health parameters was investigated: body condition score, organ weight, haematology, serum biochemistry, histopathology, clinical examination, immune response, or gastrointestinal microbiota. In most experiments, either Bt (Bacillus thuringiensis) maize, Roundup Ready (RR) soybean, or both were fed to livestock animals. Significant differences (P<0.05) in health parameters were most often observed when animals were fed Bt maize, although most effects measured were unlikely to be of biological significance and were within normal biological ranges. Health effects of RR soybean were only observed in one experimental study with broilers. Based on this literature review, we conclude that there is no clear evidence that feed composed of first generation GM crops has adverse effects on animal health.

GMOs in animal agriculture: time to consider both costs and benefits in regulatory evaluations

In 2012, genetically engineered (GE) crops were grown by 17.3 million farmers on over 170 million hectares. Over 70% of harvested GE biomass is fed to food producing animals, making them the major consumers of GE crops for the past 15 plus years. Prior to commercialization, GE crops go through an extensive regulatory evaluation. Over one hundred regulatory submissions have shown compositional equivalence, and comparable levels of safety, between GE crops and their conventional counterparts. One component of regulatory compliance is whole GE food/feed animal feeding studies. Both regulatory studies and independent peer-reviewed studies have shown that GE crops can be safely used in animal feed, and rDNA fragments have never been detected in products (e.g. milk, meat, eggs) derived from animals that consumed GE feed. Despite the fact that the scientific weight of evidence from these hundreds of studies have not revealed unique risks associated with GE feed, some groups are calling for more animal feeding studies, including long-term rodent studies and studies in target livestock species for the approval of GE crops. It is an opportune time to review the results of such studies as have been done to date to evaluate the value of the additional information obtained. Requiring long-term and target animal feeding studies would sharply increase regulatory compliance costs and prolong the regulatory process associated with the commercialization of GE crops. Such costs may impede the development of feed crops with enhanced nutritional characteristics and durability, particularly in the local varieties in small and poor developing countries. More generally it is time for regulatory evaluations to more explicitly consider both the reasonable and unique risks and benefits associated with the use of both GE plants and animals in agricultural systems, and weigh them against those associated with existing systems, and those of regulatory inaction. This would represent a shift away from a GE evaluation process that currently focuses only on risk assessment and identifying ever diminishing marginal hazards, to a regulatory approach that more objectively evaluates and communicates the likely impact of approving a new GE plant or animal on agricultural production systems.

Assessment of GE food safety using '-omics' techniques and long-term animal feeding studies

Despite the fact that a thorough, lengthy and costly evaluation of genetically engineered (GE) crop plants (including compositional analysis and toxicological tests) is imposed before marketing some European citizens remain sceptical of the safety of GE food and feed. In this context, are additional tests necessary? If so, what can we learn from them? To address these questions, we examined data from 60 recent high-throughput '-omics' comparisons between GE and non-GE crop lines and 17 recent long-term animal feeding studies (longer than the classical 90-day subchronic toxicological tests), as well as 16 multigenerational studies on animals. The '-omics' comparisons revealed that the genetic modification has less impact on plant gene expression and composition than that of conventional plant breeding. Moreover, environmental factors (such as field location, sampling time, or agricultural practices) have a greater impact than transgenesis. None of these '-omics' profiling studies has raised new safety concerns about GE varieties; neither did the long-term and multigenerational studies on animals. Therefore, there is no need to perform such long-term studies in a case-by-case approach, unless reasonable doubt still exists after conducting a 90-day feeding test. In addition, plant compositional analysis and '-omics' profiling do not indicate that toxicological tests should be mandatory. We discuss what complementary fundamental studies should be performed and how to choose the most efficient experimental design to assess risks associated with new GE traits. The possible need to update the current regulatory framework is discussed.