Klaudia Čobanová

Effects of deoxynivalenol and zearalenone on oxidative stress and blood phagocytic activity in broilers

Effects of dietary contamination with various levels of deoxynivalenol (DON) and zearalenone (ZEA) were investigated on Ross 308 hybrid broilers of both sexes. After hatching, all chickens were fed an identical control diet for two weeks. Then chickens of Group 1 received a diet contaminated with DON and ZEA, both being 3.4 mg · kg−1, while Group 2 received DON and ZEA at 8.2 and 8.3 mg · kg−1, respectively. The diet of the control group contained background levels of mycotoxins. Samples of blood and tissues were collected after two weeks. Intake of both contaminated diets resulted in a significantly decreased activity of glutathione peroxidase (GPx) and increased level of malondialdehyde (MDA) in liver tissue, while in kidneys the concentration of MDA was significantly increased only in Group 1. On the other hand, activities of blood GPx and plasma γ-glutamyltransferase (GGT) were elevated in Group 2 only. Activities of thioredoxin reductase in liver and GPx in duodenal mucosa tissues, superoxide dismutase (SOD) in erythrocytes as well as levels of MDA in duodenal mucosa and α-tocopherol in plasma were not affected by dietary mycotoxins. Blood phagocytic activity was significantly depressed in Group 1 and 2. These results demonstrate that diets contaminated with DON and ZEA at medium levels are already able to induce oxidative stress and compromise the blood phagocytic activity in fattening chickens.

Effect of Enterococcus faecium AL41 and Thymus vulgaris essential oil on small intestine integrity and antioxidative status of laying hens.

We investigated the effect of Enterococcus faecium on phagocytic activity, antioxidative status in vivo and the effect of E. faecium and 0.4% concentration of Thymus vulgaris essential oil (EO) on the duodenal tissue integrity in vitro in laying hens. The birds were fed the same standard diets and were divided into four groups. E. faecium was added to the drinking water for the second and fourth groups. EO was added to special chambers for measuring trans-epithelial electrical resistance (TEER) for the third and fourth groups only. TEER was lower in groups where EO was added, but in the group with E. faecium TEER was not changed significantly. Our results show that EO at 0.4% concentration may negatively affect intestine integrity, and the probiotic strain E. faecium AL41 is able to eliminate this effect and can strengthen non-specific immunity. To confirm our findings further histopathological investigations of intestinal tissue are needed.

Effect of thyme oil on small intestine integrity and antioxidant status, phagocytic activity and gastrointestinal microbiota in rabbits.

The effects of 0.5 g thyme oil per kg dry matter (DM) of diet on duodenal tissue integrity, antioxidant status, phagocytic activity and selected microbiota in the caecum and faeces of rabbits were studied. Twenty-four rabbits were divided into two groups and were fed a commercial granulated diet for growing rabbits (CD) with access to water ad libitum. The first group was fed the CD, while to the CD of the second group thyme oil was added. Intestinal integrity was tested by measuring the transepithelial electrical resistance (TEER). Thyme oil significantly increased the value of total antioxidant status (TAS) in the blood plasma and glutathione peroxidase (GPx) activity in the liver, and it decreased malondialdehyde (MDA) concentration in the duodenal tissue. Thyme oil resulted in strengthened intestinal integrity, as the essential oil supplementation significantly increased TEER values in the experiment. The faecal microbiota of rabbits was almost completely balanced in both groups, and only a slight decrease was found in the microbial population at day 42 of the trial. In both groups, the bacterial counts were generally lower in the caecum than in the faecal samples. In conclusion, dietary supplementation with 0.5 g/kg DM thyme oil may improve intestinal integrity, and it may have an antioxidant effect. A tendency was also found for thyme oil to stimulate the abundance of some microbes beneficial in the rabbit gut.

Can enterocins affect phagocytosis and glutathione-peroxidase in rabbits?

The gastrointestinal microbiota in rabbits play an important role in protection against potential pathogens via the development of the mucosal immune system. The gut health, including the microbial and immunological stability, is often influenced by exogenous factors, mainly around the weaning period. Therefore, alternative strategies are required to improve the animal’s health. In this study, the diet of rabbits was supplemented with the semi-purified enterocins Ent 2019, Ent M and Ent 4231, produced by bacteriocinogenic strains with probiotic properties, rabbit-derived Enterococcus faecium CCM7420 and non rabbit-derived E. faecium strains AL41 and CCM4231. The phagocytic activity, index of phagocytic activity and the gluthatione-peroxidase enzyme activity in blood were determined during the Ents consumption and also 3 weeks after their cessation. At 21 days into the experiment the highest phagocytic activity was observed in rabbits receiving Ent M. A significant increase in phagocytosis was noted in rabbits with Ent 2019 over the entire experiment. Moreover, a lower gluthatione-peroxidase activity was measured in rabbits receiving Ent M and Ent 2019. No effect of Ent 4231 application on the tested parameters was recorded. The Ent M and Ent 2019 improved the digestive immunity and the host’s defense capacities by stimulating leucocyte phagocytosis, without oxidative stress induction in rabbits.

Effect of lignin on oxidative stress in chickens fed a diet contaminated with zearalenone

The effect of lignin supplementation to a diet contaminated with zearalenone (ZEA) on antioxidant status was studied in female chickens of the ISA BROWN laying strain. From the day of hatching to 2 weeks of age, four groups of chickens were fed the same uncontaminated control diet. After 14 days, Group 1 (control) continued to receive the uncontaminated diet, while Group 2 was fed an identical diet enriched with 0.5% chemically modified lignin. Simultaneously, chickens of Group 3 were switched to a diet contaminated with 7.9 mg/kg ZEA and those of Group 4 to an identical contaminated diet supplemented with 0.5% lignin. At 6 weeks of age blood and tissue samples were collected. Feeding of a diet contaminated with a high level of ZEA resulted in elevated glutathione peroxidase (GPx) activity in the duodenal mucosa and kidney tissues, and an increased γ-glutamyltransferase (GGT) activity in the plasma, indicative of oxidative stress. In the liver tissue, no mycotoxin-induced response in GPx and thioredoxin reductase (TrxR) activities occurred, and the malondialdehyde (MDA) level was even reduced. Neither the plasma levels of retinol and α-tocopherol nor the activities of superoxide dismutase in erythrocytes and GPx in blood were affected in birds fed the contaminated diet. The only effect of lignin supplemented to the contaminated feed was that it prevented the increase of GPx activity in the duodenal mucosa as an indicator of oxidative stress.

Dietary manganese source does not affect Mn, Zn and Cu tissue deposition and the activity of manganese-containing enzymes in lambs

Manganese (Mn) is a trace element required for normal physiological processes in animals and humans. Organic forms of trace elements are expected to have higher bioavailability in comparison with inorganic sources. The effect of feeding a diet supplemented with different sources of manganese to lambs was studied in a 112-d feeding trial. The aim of this study was to investigate the deposition of Mn in relation to activities of superoxide dismutase (SOD), manganese superoxide dismutase (MnSOD) and arginase in the tissues of lambs fed the diet supplemented with an inorganic or an organic source of manganese up to the maximum total Mn content allowed in the European Union (150mg Mn/kg). A total of eighteen female lambs of the improved Valachian breed were randomly allocated to three dietary treatments and fed an unsupplemented basal diet (Control, 31mg Mn/kg) or the identical diet supplemented with manganese sulphate (MnSO4) or manganese chelate of glycine hydrate (Mn-Gly) with a total Mn content up to 150mg/kg. Regardless of the source, feed supplementation with manganese increased Mn concentrations in plasma (P˂0.05) and the liver (P˂0.001) as well as the activity of liver MnSOD (P˂0.05) and arginase (P˂0.001) compared with the control lambs. In the kidney cortex, the concentration of Mn was greatest in lambs fed the diet supplemented with the chelated Mn source compared with animals receiving the inorganic Mn source (P˂0.05) and the unsupplemented diet (P˂0.001). The 112-d intake of feed enriched with manganese did not result in any change in Mn levels, SOD or MnSOD activity in pancreas and kidney tissues. Plasma Cu concentration was depressed in both supplemented treatments. No analyzed tissue showed a change in zinc and copper levels, except the greater Cu concentration in the liver of lambs fed the diet with Mn-Gly. The presented results did not indicate any differences between dietary Mn sources either in Mn tissue deposition or activity of SOD, MnSOD and arginase in lamb tissues; however, it seems that manganese intake of up to 150mg/kg in feed may decrease plasma Cu concentration in lambs.

Experimental addition of Eleutherococcus senticosus and probiotic to the canine diet

There is a current trend to support pet health through the addition of natural supplements to their diet, taking into account the high incidence of medical conditions related to their immune system and gastrointestinal tract. This study investigates effects of the plant Eleutherococcus senticosus as a dietary additive on faecal microbiota, faecal characteristics, blood serum biochemistry and selected parameters of cellular immunity in healthy dogs. A combination of the plant with the canine-derived probiotic strain Lactobacillus fermentum CCM 7421 was also evaluated. Thirty-two dogs were devided into 4 treatment groups; receiving no additive (control), dry root extract of E. senticosus (8 mg/kg of body weight), probiotic strain (108 CFU/mL, 0.1 mL/kg bw) and the combination of both additives. The trial lasted 49 days with 14 days supplementation period. Results confirm no antimicrobial effect of the plant on the probiotic abundance either in vitro (cultivation test) or in vivo. The numbers of clostridia, lactic acid bacteria and Gram-negative bacteria as well as the concentration of serum total protein, triglyceride, glucose and aspartate aminotransferase were significantly altered according to the treatment group. Leukocyte phagocytosis was significantly stimulated by the addition of probiotic while application of plant alone led to a significant decrease.

Effects of diet supplementation with herbal blend and sunflower seeds on fermentation parameters, microbial population, and fatty acid profile in rumen of sheep

The study evaluated the rumen fermentation pattern, microbial population, fatty acid composition, and antioxidant status in the rumen fluid and blood of sheep in response to a diet supplemented with herbal blend (HB), sunflower seeds (SS), and a combination of both HB and SS (HBSS). The HB consisted of medicinal herbs typical for Central Europe. Four rumen fistulated rams were used in a 4 × 4 Latin square design and were fed a basal diet consisting of meadow hay (720 g dry matter (DM)/day) and barley grain (540 g DM/day) in the ratio of 60 : 40 and supplemented with no additive (Control), HB (10% replacement of meadow hay), SS (180 g DM/day), and HBSS (HB + SS). An increase in the molar proportion of iso-butyrate (P = 0.009) and iso-valerate (P = 0.034) was observed in the SS and HBSS diets as well as of ammonia N concentration in the HB, SS, and HBSS diets compared to control (P = 0.003). Concentrations of monounsaturated fatty acids of the HB, SS, and HBSS diets were increased (P = 0.041) compared to control, whereas concentrations of polyunsaturated fatty acids in the SS and HBSS diets were decreased (P = 0.023). Phagocytic activity in the blood was higher with all the diets vs control (P = 0.001). Qualitative evaluation of microbial population by denaturing gradient gel electrophoresis (DGGE) and principal component analysis (PCA) revealed no effects of dietary treatments on the composition of both eubacterial and ciliated protozoal populations. However, in spite of the supplementation of forage-concentrate diet by HB in the presence of SS, no negative effects on the fermentation patterns and rumen microbial population have been detected.

Enterocin 4231 produced by Enterococcus faecium CCM 4231 and its use in rabbits.

The aim of this experiment was to study the effect of Enterocin (Ent) 4231 produced by Enterococcus faecium. The group of 48 rabbits (Hy-Plus breed) was divided into experimental (EG) and control (CG) group. In EG Ent 4231 was applied for 21 days in a dose of 50 μL/animal/day into drinking water. The experiment lasted for 42 days. Samples were collected on day 0-1, day 7, day 21 (3 weeks of administration) and on day 42 (3 weeks after cessation of application) to measure the occurence of Eimeria sp. oocysts. Samples of caecal contents were collected on days 21 and 42 to determine bacterial counts. The phagocytic activity was examined on days 0-1, 21 and 42. On days 21 and 42 the reduction of Clostridium-like sp. was detected in EG (difference 1.53 log10 CFU/g; 1.57 log10 CFU/g) in comparison with CG. In EG on day 7 the decrease of E. coli (difference 1.30 log10 CFU/g) was also noted in comparison with CG. In EG prolonged immunostimulative effect (p<0.001) was observed on day 42 in comparison with CG. The oocysts of Eimeria sp. were reduced in EG comparing with CG at day 42. Enrichment of the diet for rabbits with Ent 4231 did not influence biochemical, zootechnical parameters and the values of caecal content volatile acids during the whole experiment.

Effects of borneol on blood chemistry changes in chickens.

It is well established that borneol may be alter bone metabolism. The aim of the study was to investigate the effects of feeding diets supplemented with borneol on blood biochemistry of chickens. Forty chicks of a commercial strain ISA Brown were divided into five groups with 8 birds in each and fed diets supplemented with 0%, 0.1%, 0.05% or 0.025% borneol dissolved in sunflower oil from hatching up to week 11. The concentrations of potassium and magnesium were found to be significantly higher in chickens fed the diet supplemented with 0.1% and 0.025% borneol, respectively. The blood plasma levels of total protein and glucose in chickens treated with 0.05% borneol were significantly lowered. Feeding of diets supplemented with borneol significantly increased levels of bilirubin, cholesterol and total lipids in blood plasma compared to the control group supplemented with sunflower oil only. The present study shows that addition of borneol to the diets can influence some parameters of mineral, lipid and protein metabolism in chicken blood plasma.