Supplemental dietary selenium enhances immune responses conferred by a vaccine against low pathogenicity avian influenza virus.

Selenium is a trace mineral that has antioxidant activities and can influence the immune system. However, antiviral effects of selenium have not been well studies in chickens. Chickens were therefore fed diets supplemented with two levels of two different sources of selenium (organic: selenium enriched yeast; SEY or inorganic: sodium selenite; SS). Chickens in the control groups did not receive supplemental dietary selenium. At 14 and 21 days of age, chickens were vaccinated with an inactivated low pathogenicity avian influenza virus (AIV, subtype H9N2) vaccine and blood samples were collected to determine the level of antibodies using hemagglutination inhibition (HI) and ELISA. At 30 days of age, chickens were also challenged with the same virus and swab samples were collected to assess the amount of virus shedding. Antibody levels, as measured by HI, increased significantly in the chickens that received higher levels of SEY at 16 days post vaccination. ELISA titers for IgM and IgY were higher in selenium supplemented chickens. Comparing to challenged control, virus shedding was lower in organic as well as inorganic selenium treated groups. Therefore, it may be concluded that supplemental dietary selenium could enhance vaccine conferred immunity thereby impacting protection against viral challenge in chickens.

Comparative Seasonal Respiratory Virus Epidemic Timing in Utah.

Previous studies have found evidence of viral interference between seasonal respiratory viruses. Using laboratory-confirmed data from a Utah-based healthcare provider, Intermountain Health Care, we analyzed the time-specific patterns of respiratory syncytial virus (RSV), influenza A, influenza B, human metapneumovirus, rhinovirus, and enterovirus circulation from 2004 to 2018, using descriptive methods and wavelet analysis (n = 89,462) on a local level. The results showed that RSV virus dynamics in Utah were the most consistent of any of the viruses studied, and that the other seasonal viruses were generally in synchrony with RSV, except for enterovirus (which mostly occurs late summer to early fall) and influenza A and B during pandemic years.

Dietary selenium supplementation enhances antiviral immunity in chickens challenged with low pathogenic avian influenza virus subtype H9N2.

Selenium supplementation in poultry feeds has been known to have beneficial effects on the bird health and performance; however antiviral effects of selenium have remained largely unknown. In this study, we have evaluated the effects of supplementation of chicken diets with organic (Selenium Enriched Yeast; SEY) and inorganic selenium (Sodium Selenite; SS) on low pathogenicity avian influenza virus (H9N2) shedding in the cloacal and oropharyngeal swab samples as well as examined the expression of immune related genes. Chickens were fed two doses (High- 0.30 mg/kg of feed; Low- 0.15 mg/kg of feed) of selenium supplementation for 2 weeks followed by low pathogenicity avian influenza virus challenge. Our results showed that the cloacal shedding of virus in all the selenium supplemented groups was significantly lower when compared to the non-supplemented control groups. In addition, the oropharyngeal shedding of virus in chickens fed with organic selenium supplementation was significantly lower than that in the chickens that received either inorganic selenium supplemented feed or controls. Furthermore, the expression of interferon stimulated genes (Viperin, OAS: 2'-5' oligoadenylate synthetase and MDA5: melanoma differentiation-associated gene) in the cecal tonsils was significantly elevated in the selenium treated groups when compared to controls. Additionally, a significantly higher transcription of interferon (IFN)-α, IFN-ß and IFN-γ genes in the cecal tonsils and spleens of chickens receiving SEY-L and SS-H supplemented feed was also observed at post virus challenge time points compared to untreated controls. The results of this study demonstrated that supplementation of chicken diets with selenium, can enhance antiviral defense and thus, may have a beneficial effect in controlling viral infections in poultry.

Radioprotective agents to prevent cellular damage due to ionizing radiation.

Medical imaging has become a central component of patient care to ensure early and accurate diagnosis. Unfortunately, many imaging modalities use ionizing radiation to generate images. Ionizing radiation even in low doses can cause direct DNA damage and generate reactive oxygen species and free radicals, leading to DNA, protein, and lipid membrane damage. This cell damage can lead to apoptosis, necrosis, teratogenesis, or carcinogenesis. As many as 2% of cancers (and an associated 15,000 deaths annually) can be linked to computed tomography exposure alone. Radioprotective agents have been investigated using various models including cells, animals, and recently humans. The data suggest that radioprotective agents working through a variety of mechanisms have the potential to decrease free radical damage produced by ionizing radiation. Radioprotective agents may be useful as an adjunct to medical imaging to reduced patient morbidity and mortality due to ionizing radiation exposure. Some radioprotective agents can be found in high quantities in antioxidant rich foods, suggesting that a specific diet recommendation could be beneficial in radioprotection.

Effect of Penicillium mycotoxins on the cytokine gene expression, reactive oxygen species production, and phagocytosis of bovine macrophage (BoMacs) function.

Bovine macrophages (BoMacs) were exposed to the following Penicillium mycotoxins (PM): citrinin (CIT), ochratoxin A (OTA), patulin (PAT), mycophenolic acid (MPA) and penicillic acid (PA). PM exposure at the concentration that inhibits proliferation by 25% (IC25) differentially for 24h altered the gene expression of various cytokines. OTA significantly induced IL-1α expression (p<0.05), while the expression of IL-6 was suppressed (p<0.01). MPA significantly induced the expression of IL-1α (p<0.05) and reduced the expression of IL-12α (p<0.01) and IL-10 (p<0.01). PAT significantly suppressed the expression of IL-23 (p<0.01), IL-10 (p<0.05) and TGF-ß (p<0.05). Some PMs also affected reactive oxygen species (ROS) and phagocytosis of Mycobacterium avium ssp. Paratuberculosis (MAP) at higher concentrations. PAT and PA for example, significantly decreased the percent phagocytosis of MAP at 5.0 (p<0.01) and 15.6 µM (p<0.01), respectively, but only PA significantly suppressed PAM-3-stimulated ROS production at 62.5 (p<0.05) and 250.0 µM (p<0.01). OTA significantly increased the percent phagocytosis of MAP at 6.3 (p<0.05) and 12.5 µM (p<0.01). These findings suggest that exposure to sub-lethal concentrations of PMs can affect macrophage function, which could affect immunoregulation and innate disease resistance to pathogens.

The effects of feed-borne Fusarium mycotoxins and glucomannan in turkey poults based on specific and non-specific parameters.

An experiment was conducted to investigate the effects of feeding grains naturally contaminated with Fusarium mycotoxins and a yeast derived glucomannan mycotoxin adsorbent (GMA) on selected specific and non-specific parameters in turkey poults. Two hundred and forty 1-day-old male turkey poults were fed the experimental diets for twelve weeks. Experimental diets were formulated with control grains, control grains+0.2% GMA, naturally-contaminated grains, or naturally-contaminated grains+0.2% GMA. Deoxynivalenol (DON) was the major contaminant of the contaminated grains and concentrations varied from 4.0 to 6.5 mg/kg in the contaminated diets. Non-specific parameters measured included: performance parameters, plasma biochemistry profiles, morphometry and CD8(+) T-lymphocyte counts in the duodenum. Plasma concentrations of DON and de-epoxydeoxynivalenol (DOM-1) were used as specific parameters. Performance parameters and plasma biochemistry were altered by the feeding of contaminated diets and GMA but this was not consistent throughout the trial. The feeding of contaminated diets reduced duodenal villus height and apparent villus surface area. This effect was prevented by GMA supplementation. The feeding of contaminated diets elevated total duodenal CD8(+) T-lymphocyte counts but this effect was not prevented by GMA. No significant differences were seen in plasma concentrations of DON and DOM-1 comparing birds fed contaminated and contaminated+GMA diets suggesting that GMA did not prevent DON absorption under these conditions.

A survey of free and conjugated deoxynivalenol in the 2008 corn crop in Ontario, Canada.

BACKGROUND: Deoxynivalenol (DON, vomitoxin), one of the most important mycotoxins produced by many Fusarium species, is found as a common contaminant of crops worldwide. Recent studies have described the presence of conjugated forms of DON (glycosides and fatty acid). The aim of the current study was therefore to investigate the natural occurrence of free and conjugated DON in Canadian corn. RESULTS: Free and conjugated DON was determined by gas chromatography-mass spectrometry (GC-MS) and enzyme-linked immunosorbent assay (ELISA) in 86 corn samples collected from the 2008 crop in Ontario, Canada. Free DON concentrations determined by ELISA were similar to values determined in most samples using GC-MS. Conjugated DON was detected in 72 samples. Levels of free DON ranged from 0.17 to 14.00 µg g(-1) using GC-MS. The highest levels of free DON were found in corn samples from the southern and southwestern regions of Ontario, while samples from eastern regions were less contaminated. Conjugated DON was found mainly in corn from the east-central region, with five of six samples showing high levels of conjugated DON (up to 43% increase in DON following acid hydrolysis). Low levels of conjugated DON (≤ 10% increase in DON following acid hydrolysis) were detected in the majority of corn samples from the southwestern region (nine of 19 samples) and from the central region (16 of 36 samples). CONCLUSION: The current survey emphasizes the frequency of conjugated DON in Ontario grown corn and the potential challenges in understanding the hazard posed by DON-contaminated foodstuffs and feedstuffs.

Effects of feed-borne Fusarium mycotoxins and an organic mycotoxin adsorbent on immune cell dynamics in the jejunum of chickens infected with Eimeria maxima.

An experiment was conducted to explore the effects of Fusarium mycotoxins, common animal feed contaminants, on intestinal immune responses to coccidia (Eimeria) in chickens. Effects of feed-borne Fusarium mycotoxins and a polymeric glucomannan mycotoxin adsorbent (GMA) on immune cell populations were studied in the jejunum of broiler breeder pullets using an Eimeria maxima infection model. Birds were fed a control diet, a diet naturally contaminated with Fusarium mycotoxins, contaminated diet plus 0.2% GMA, or control diet plus 0.2% GMA. Contaminated diets contained up to 6.5µg/g deoxynivalenol (DON), 0.47µg/g 15-acetyl-DON and 0.73µg/g zearalenone. Birds received a primary oral inoculation (1000 oocysts/bird) with E. maxima USDA strain 68 at 2 weeks of age and a secondary oral inoculation (30,000 oocysts/bird) with the same strain at 4 weeks of age. Diet-related differences in CD4(+) cell, CD8(+) cell and macrophage recruitment pattern into the jejunum were observed following both the primary and secondary infections. It was concluded that feed-borne Fusarium mycotoxins and GMA have the potential to modulate immune response to coccidial infections.

Immunomodulatory effects of feed-borne Fusarium mycotoxins in chickens infected with coccidia.

The potential for Fusarium mycotoxins to modulate immunity was studied in chickens raised to 10 weeks of age using an enteric coccidial infection model. Experimental diets included: control, diets containing grains naturally contaminated with Fusarium mycotoxins, and diets containing contaminated grains + 0.2% polymeric glucomannan mycotoxin adsorbent (GMA). Contaminated diets contained up to 3.8 microg/g deoxynivalenol (DON), 0.3 microg/g 15-acetyl DON and 0.2 microg/g zearalenone. An optimized mixture (inducing lesions without mortality) of Eimeria acervulina, E. maxima and E. tenella was used to challenge birds at 8 weeks of age. Immune parameters were studied prior to challenge, at the end of the challenge period (7 days post-inoculation, PI), and at the end of the recovery period (14 days PI). Total serum immunoglobulin (Ig) A and IgG concentrations in challenged birds fed the contaminated diet were higher than controls at the end of the challenge period. Serum concentration of IgA, but not IgG, was significantly decreased at the end of the recovery period in birds fed the contaminated diet. The percentage of CD4+ and CD8+ cell populations in blood mononuclear cells decreased significantly at the end of the challenge period in birds fed the control or the contaminated diet compared to their percentages prior to challenge. The pre-challenge percentage of CD8+ population was restored at the end of the recovery period only in birds fed the control diet. Interferon-gamma (IFN-gamma) gene expression in caecal tonsils was up-regulated in challenged birds fed the contaminated diet at the end of the challenge period. No significant effect of diet was observed on oocyst counts despite the changes in the studied immune parameters. It was concluded that Fusarium mycotoxins modulate the avian immune system. This modulation involves alteration of gene expression but apparently does not enhance susceptibility or resistance to a primary coccidial challenge.

Effects of foodborne Fusarium mycotoxins with and without a polymeric glucomannan mycotoxin adsorbent on food intake and nutrient digestibility, body weight, and physical and clinicopathologic variables of mature dogs.

OBJECTIVE: To investigate the effects of feeding cereal-based diets that are naturally contaminated with Fusarium mycotoxins to dogs and assess the efficacy of a polymeric glucomannan mycotoxin adsorbent (GMA) in prevention of Fusarium mycotoxicosis. ANIMALS: 12 mature female Beagles. PROCEDURES: Dogs received each of 3 cereal-based diets for 14 days. One diet was uncontaminated (control diet), and the other 2 contained contaminated grains; one of the contaminated diets also contained 0.2% GMA. Contaminants included deoxynivalenol, 15-acetyl deoxynivalenol, zearalenone, and fusaric acid. Food intake and nutrient digestibility, body weight, blood pressure, heart rate, and clinicopathologic variables of the dogs were assessed at intervals during the feeding periods. RESULTS: Food intake and body weight of dogs fed the contaminated diet without GMA were significantly decreased, compared with effects of the control diet. Reductions in blood pressure; heart rate; serum concentrations of total protein, globulin, and fibrinogen; and serum activities of alkaline phosphatase and amylase as well as increases in blood monocyte count and mean corpuscular volume were detected. Consumption of GMA did not ameliorate the effects of the Fusarium mycotoxins. For the GMA-contaminated diet, digestibility of carbohydrate, protein, and lipid was significantly higher than that associated with the control diet, possibly because of physiologic adaptation of the recipient dogs to reduced food intake. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that consumption of grains naturally contaminated with Fusarium mycotoxins can adversely affect dogs' feeding behaviors and metabolism. As a food additive, GMA was not effective in prevention of Fusarium mycotoxicosis in dogs.

Mycotoxins in pet food: a review on worldwide prevalence and preventative strategies.

Mycotoxins contaminate cereal grains worldwide, and their presence in pet food has been a potential health threat to companion animals. Aflatoxins, ochratoxin A, and Fusarium mycotoxins have been found in both raw ingredients and final products of pet food around the globe. Aflatoxin, a hepatotoxin and carcinogen, has caused several food poisoning outbreaks in dogs, and aflatoxin content is regulated in pet food in many countries. Ochratoxin A and Fusarium mycotoxins including trichothecenes, zearalenone, and fumonisins may have chronic effects on the health of companion animals. Grain processing, sampling error, analytical methods, conjugated mycotoxins, storage conditions, and synergistic interactions are common challenges faced by the pet food industry. Food-processing techniques such as sieving, washing, pearling, ozonation, and acid-based mold inhibition reduce the mycotoxin content of cereal grains. Dietary supplementation with large neutral amino acids, antioxidants, and omega-3 polysaturated fatty acids as well as inclusion of mycotoxin-sequestering agents and detoxifying microbes may ameliorate the harmful effects of mycotoxins in contaminated pet food.

Dietary putrescine (1,4-diaminobutane) influences recovery of Turkey poults challenged with a mixed coccidial infection.

Exogenous dietary putrescine (1,4-diaminobutane) can increase growth rates of neonatal animals, including calves, chicks, and piglets, under nutritional stress. Turkey poults often have a high mortality rate and this may be due to poor initial feeding behavior and inadequate development of the intestinal tract. We conducted an experiment to determine the effect of dietary putrescine supplementation on growth performance and the role of dietary putrescine in prevention and recovery from a coccidial challenge. A total of 160 1-d-old turkey poults were fed a corn and soybean meal-based starter diet supplemented with 0.0 (control), 0.1, 0.2, and 0.3 g/100 g purified putrescine (8 birds/pen, 5 pens/diet). At 14 d of age, half the birds were infected with approximately 43,000 sporulated oocysts. The experiment lasted 24 d. Fecal samples were gathered from d 3 to d 5 postinfection by total collection. Ten control and 10 infected birds fed each diet were sampled on d 6 and d 10 postinfection. The induced infection produced significant depressions in growth and feed intake and detrimental morphological changes in the small intestine of poults in the absence of mortality. Weight gains, protein content of jejunum, and morphometric indices of duodenum, jejunum, and ileum were greater in challenged poults fed 0.3 g/100 g putrescine than in controls. We conclude that dietary putrescine supplementation may be beneficial to poult growth, mucosal development of the small intestine, and to recovery from subclinical coccidiosis.