The effect of feeding corn molded with Penicillium lanosum to broiler chicks

Effects of Glucose Oxidase Supplementation on the Growth Performance, Antioxidative and Inflammatory Status, Gut Function, and Microbiota Composition of Broilers Fed Moldy Corn

Background

Glucose oxidase is widely used as a livestock feed additive owing to its beneficial effects on growth performance and antioxidant activity. However, little is known about the effects of the enzyme on intestinal health.

Methods

To investigate the effects of glucose oxidase supplementation on the growth performance, intestinal function, and microbiota composition of broilers fed moldy corn, newly hatched Arbor Acres broilers were each randomly assigned to one of four groups, which were fed a basal diet (CON), a contaminated diet (10% moldy corn) (MC), a basal diet supplemented with 0.01% glucose oxidase (GOD), or a contaminated diet supplemented with 0.01% glucose oxidase (MCG).

Results

We found that the average weight gain (ADG) of the MC group was significantly lower than those of the CON and GOD groups, and there were no significant differences in ADG between the MCG group and the CON and GOD groups. Intestinal morphology results revealed irregularly arranged villi and microvilli in the ilea from the MC group, whereas those from the other three groups were aligned regularly. Tight-junction protein analysis showed that both ZO-1 expression and claudin-4 expression in the MC group were significantly lower than those in the other groups. Inflammation cytokines analysis showed lower serum concentration of interleukin-10, as well as its mRNA expression in the ileum of the MC group, when compared with those of the other groups. Additionally, we observed lower glutathione peroxidase and total superoxide dismutase activity and higher malonaldehyde concentration in the MC group than those in the MCG group. The α and β diversity of microbiota profiling indicated that the cecal microbiota in the MC group differed from those in the other three groups.

Conclusion

The results indicated that glucose oxidase supplementation was able to prevent the adverse effects from mycotoxin exposure on growth performance, antioxidant activity, inflammatory response, intestinal function, and microbiota composition in broilers. We suggested that glucose oxidase supplementation can be used in broilers to mitigate the adverse effects of moldy feed, and its benefits are due to its effect on intestinal microbiota composition.

Stress induced gizzard erosion in chicks. I. Gross and histopathological findings

A model of stress induced gizzard erosions is described. Three day old chickens were deprived of food for 24 h, and after that they were immersed in tap water (17 degrees C) for five seconds. Group A was sacrificed immediately before being subjected to stress, group B one hour, group C two hours and group D three hours after water immersion stress. Each group consisted of 10 animals. Gizzard lesions in group A were very mild and the main feature was discoloration of the gizzard lining. In groups B, C, and D the lesions were more severe and they were characterised by gizzard erosions, ulcerations and hemorrhages especially pronounced in group D. This model produced lesions in all stressed animals.

Effect of feeding rabbits on naturally moulded and mycotoxin-contaminated diet

For studying the effects of naturally moulded diet on mature female-rabbits, Buskat rabbits were fed for 6 weeks on a naturally moulded diet comparing with the other similar group of animals which was fed also on the same ingredients in the first diet, except that, they were sound (not moulded apparently). The results which were obtained from this study due to the feeding on the moulded diet were as follows: 1. Decreasing the feed intake significantly (P less than 5%) and increasing somewhat the water consumption, but the water/feed ratio increased significantly (P less than 5%). 2. Reduction of the digestibility of most nutrients, especially of the crude fibre (P less than 1%) and crude protein (P less than or equal to 5%). 3. Changing in the relative weights of different organs particularly the significant (P less than 5%) decrease in weight of the liver and spleen as well as the significant (P less than 5%) increase in weight of empty stomach and female genital tract. 4. The most important haematological changes were the reduction in cholesterol content and the elevation of phospholipid concentration, thus the cholesterol/phospholipid ratio decreased by the rate of 40.7%. Calcium/phosphorus ratio increased by the rate of 9.5% as a result of increasing calcium content in the control serum. 5. Chemical analyses revealed a significant (P less than 1%) reduction in ash content of the liver and magnesium content of the tibia bone, a slight decrease in liver content of iron and ether extract, and significant (P less than 5%) rise in femoral muscle content of the ether extract.

Citrinin toxicity in young chicks

Two experiments were conducted to demonstrate the capacity of citrinin to cause dose-related increases in water consumption and urine excretion. In Experiment 1, chicks 24 days old were fed mixtures of untreated and inoculated corn containing citrinin to provide 0, 50, 100, 150, 200, and 250 micrograms of the toxin per gram of blended corn. The corn was fed for 4 hr, and water intake and urine excretion were measured. Chicks consumed 0, 1.23, 2.37, 3.68, 4.26 and 5.44 mg citrinin from the respective treatments. Compared with chicks consuming no citrinin, water intake and urine excretion of treated chicks increased (P less than .05) when chicks consumed 3.68 mg or more citrinin. Measures of the difference between water intake and urine excretion were similar for all treatments except for chicks consuming 3.68 mg citrinin; for those chicks the difference was significantly greater (P less than .05) than for chicks consuming 1.23 mg citrinin. In Experiment 2, inoculated corn was heated in a microwave oven for 1, 2, 8, and 16 min. Temperatures of the heated corn samples, when removed from the oven, were 76 C, 100 C and 105 C, respectively. Chicks that were 28 days old were fed these various samples of corn for 4 hr. Heating corn for 2 min to a temperature of 76 C caused no apparent loss of citrinin activity based on water intake and urine excretion measures. Heating the corn for 8 min to a temperature of 100 C destroyed some of the citrinin activity. Heating citrinin-contaminated corn to 105 C for 16 min destroyed the diuretic effect of the mycotoxin.

Effect of heat drying of corn on the extraction of citrinin

Experiments were conducted to determine if drying citrinin-contaminated corn at varying temperatures and times either bound citrinin or converted it to a derivative that could not be extracted from the grain. Sterilized whole corn was inoculated with spores of a Penicillium spp. that produces citrinin and was incubated for 8 weeks. Following incubation, the corn was mixed and divided into three portions. In Experiment 1, one portion was dried at room temperature and the other portions were dried at 65 C for either 40 or 72 hr. In Experiment 2, one portion was air-dried and the other portions were dried at 60 C for 24 hr or 100 C for 3 hr. The corn was then ground to a texture suitable for feeding to chicks. Analysis of the corn indicated that temperature or length of drying time had no adverse effects on the extraction of citrinin from the corn. The citrinin was not rendered unextractable by either being bound because of heating or by being converted to a derivative. When fed to chicks for 5 hr, water consumption and urine excretion data indicated that there was no loss of citrinin activity because of method of drying.

The effect of drying method and storage time on citrinin activity in corn

Sterilized whole corn was inoculated with a Penicillium spp.,3 a citrinin-producing fungus, and incubated at room temperature for 8 weeks. The corn was then blended and divided into two parts, which were dried either in air at room temperature (ADC) or in a forced draft oven at 60 C for 24 hr (ODC). Each batch of corn was ground and stored in plastic containers. The corn was fed to broiler chicks prior to and after 3, 6, 9, and 12 months of storage at 4 C. The inoculated corn was fed undiluted or blended with noninoculated corn to give mixtures containing one-third and two-thirds of inoculated corn. Noninoculated corn, inoculated corn, and blends of the two were fed to chicks for 5 hr as the only feed. Feed consumption, water intake, and excretion were measured at the end of the test. The citrinin contents of the ADC at 3, 6, 9, and 12 mo were 824, 599, 667, and 590 ppm and were 928, 541, 781, and 490 ppm for the ODC at the same periods. Water consumption and water excretion increased as the amount of citrinin intake increased. Neither drying method nor length of storage affected the citrinin activity in the corn. The citrinin in ODC was neither bound nor converted to a derivative that was unextractable.

Toxic fungal metabolites in food

About 100 fungal metabolites may cause cancer, embryological defects, or other histopathological effects in mammals. They are produced by a wide variety of fungi. Few of these metabolites have significant acute toxicity. With the exception of aflatoxin B1 and sterigmatocystin, there is no conclusive evidence that any of them is carcinogenic. However, several of the compounds are mutagenic. Cytochalasin D and T-2 toxin are probably teratogenic. A wide variety of other histopathological effects have been shown. Liver damage has been most frequently reported. In almost all cases the molecular bases of these effects have not been extensively investigated. Although much is known about the routes by which some of the compounds are synthesized in vivo, nothing is known about control at the molecular level of these biosynthetic routes. Little is known about the biological degradation of these compounds or about the levels and incidences of them in food and animal feed. Future work in all these areas will depend on the further development of sensitive assay methods that are applicable to their measurement in food, in animal feed, and in animal tissues and body fluids and on the application of these methods to define exposure to these compounds in the diet.

Influence of temperature, moisture, and propionic acid on mold growth and toxin production on corn

The influence of temperature and propionic acid on mold growth and toxin production on whole corn with 10, 15, or 20% added water was studied. Levels of propionic acid tested at each moisture level were 0, .025, .05, and .1%. Each flask of corn was inoculated with spores of a citrinin-producing Penicillium spp. and was then incubated for 8 weeks at a constant temperature of 5 C, at 5 C at night and room temperature during the day, or at room temperature both at night and during the day. The corn was then dried, ground, and fed to chicks to determine the presence of citrinin. Regardless of acid level or moisture content, neither mold growth nor toxin production occurred on the corn incubated at 5 C. Both mold growth and toxin production occurred on corn either partially or totally incubated at room temperature but were more prevalent in the latter. Increasing the moisture content resulted in greater mold growth and toxin production, especially on the corn incubated at room temperature. Higher levels of propionic acid were needed to prevent mold growth and toxin production as the moisture content of the corn increased.

The nutritional value of moldy grains for broiler chicks

The effect was determined of mold development in corn and sorghum grains on their lipid content and nutritional value for broiler chicks. The grains, whole or ground, with their original moisture content (12.1 to 13.0%) or increased moisture content (15.0% moisture), were stored for 63 to 96 days prior to their incorporation into the diets fed to the chicks. Increasing the moisture content caused the development of the naturally occurring fungi (mainly Penicillium and Aspergillus spp.). The moldy grains did not contain aflatoxin B1, ochratoxin A, patulin, sterigmatocystin or zearalenone. Storage of whole or ground grains or of moistened whole corn did not result in differences in their fat content, in the metabolizable energy (ME) of the diets containing these grains, or in the performance of chicks fed these diets, but moistened whole sorghum affected performance adversely. Fat content in moistened ground grains decreased markedly during storage, but fatty acid ratios, vitamin E, carotene, xanthophyll, and protein levels were not markedly affected. These ground moldy grains reduced the dietary fat level during the 3 weeks of the feeding period in two out of three experiments and significantly (P less than .05) lowered ME values and depressed performance. Soybean oil supplementations to diets containing these grains increased dietary ME values and partially or completely restored performance. It is concluded, therefore, that the decreased energy level in diets containing ground moldy grains (not containing mycotoxins) is an important factor for their reduced nutritional value.

Citrinin toxicity in growing chicks

Male broiler chicks, from day-old to 3 weeks of age, were fed diets containing 0, 100, 220, 330, and 440 ppm citrinin produced by Penicillium lanosum grown on whole corn. Body weight decreased (P less than .05) when chicks were fed the diets containing 330 and 440 ppm citrinin. Average body weight of chicks fed the diet containing 220 ppm citrinin was 8% less than that of chicks fed no toxin. Feed utilization decreased (P less than .05) with chicks fed the diet containing 440 ppm citrinin. Analysis of thigh muscle, kidney, liver, and blood for citrinin revealed detectable amounts in the liver and blood of chicks fed 440 ppm.

Isolation and identification of citrinin produced by Penicillium lanosum

Penicillium lanosum, when grown on corn, produces a metabolite which increases water intake and excretion by chicks. During a 5-hr test period, chicks fed inoculated corn as the only feed began excreting water within 2 hr and excreted as much as 36 ml, whereas chicks fed untreated corn did not excrete measurable amounts. Chicks fed the inoculated corn drank more water than those fed untreated corn. The metabolite could not be extracted from oven-dried corn but was removed from air-dried corn which had been moistened with acid and extracted with chloroform and then with methanol. It was soluble in 1% sodium bicarbonate and precipitated as yellow cystals when the solution was acidified to pH 1.5. The precipitate was identified as citrinin based on the results of thin layer chromatography, ultraviolet, infrared, mass spectrometer, fluorescence excitation and emission, and nuclear magnetic resonance spectra.