Evaluation of oxidative stress and antioxidant status, serum trace mineral levels and cholinesterases activity in cattle infected with Anaplasma marginale.

This study was undertaken to assess the influence of an Anaplasma marginale infection on oxidative stress and antioxidant status, trace elements and cholinesterase as markers of the inflammatory process and biomarkers of oxidative imbalance. An infected group comprised of 35 crossbred Holstein cattle, about 2-3 years old, naturally infected with Anaplasma marginale, were divided into 4 subgroups according to their parasitemia rates (<1%, 1-10%, 10-20%, >20%) and also 10 healthy cattle as control were selected. Blood samples were taken and hematological parameters, activities of antioxidant enzymes including erythrocyte glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), catalase (CAT), glucose-6-phosphate dehydrogenase (G6PD), total antioxidant capacity (TAC), median corpuscularfragility (MCF) as well as acetylcholinesterase (AChE), and serum concentrations of antioxidant trace minerals (copper, iron, zinc, manganese, and selenium) and butyrylcholinesterase (BChE) were determined. In addition, as an index of lipid peroxidation, the level of malondialdehyde (MDA) was measured. The results revealed a significant decrease (P < 0.05) in RBC count, packed cell volume (PCV) and Hb concentration as well as the activities of erythrocyte GSH-Px, SOD, CAT, G6PD, TAC, MCF and AChE and serum concentrations of Cu, Zn, Mn, Se and BchE in the infected cattle. In contrast, significantly increased (P < 0.05) levels of MDA and erythrocyte osmotic fragility as well as serum concentration of iron were recorded in the infected animals. The significant decrease in antioxidant enzyme activities and substantial elevated levels of lipid peroxidation and erythrocyte osmotic fragility associated with the notable increase in parasitemia indicate increased exposure of RBCs to oxidative damage. Furthermore, decrease of cholinesterase in infection by A. marginale can and directly or indirectly lead to increase acetylcholine levels potent anti-inflammatory molecules, thereby inhibiting inflammation.

Assessment of oxidative/nitrosative stress biomarkers and DNA damage in Haemonchus contortus, following exposure to zinc oxide nanoparticles.

Drug resistance in helminth parasites has incurred several difficulties to livestock industry and ranked among the top public health concerns. Therefore, seeking for new agents to control parasites is an urgent strategy. In the recent years, metallic nanoparticles have been considerably evaluated for anthelmintic effects. The current research was conducted to assess possible anthelmintic impacts of zinc oxide nanoparticles (ZnO-NPs) on a prevalent gastrointestinal nematode, H. contortus. Moreover, several biomarkers of oxidative/nitrosative stress and DNA damage were measured. Various concentrations of the nanoparticle were prepared and incubated with the worms for 24 hours. The parasite mobility, mortality rate, antioxidant enzymes activities (SOD, Catalase and GSH-Px), lipid peroxidation, total antioxidant status as well as nitric oxide (NO) contents and DNA damage were determined. ZnO-NPs exerted significant wormicidal effects via induction of oxidative/nitrosative stress and DNA damage. Conclusively, ZnO-NPs can be utilized as a novel and potential agent to control and treatment of helminth parasitic infections.

Study on the Relationship between Liver Parasitic Infections and Serum Vitamin A and ß-Carotene Status in Cattle.

OBJECTIVE: This study was conducted to evaluate the relationship between serum levels of vitamin A and ß-carotene in the liver of cattle. METHODS: A total number of 150 samples were selected according to the type of parasitic infections of the liver after postmortem examination and confirmation. Parasitic lesions in the liver were subdivided into three major parasites, including Fasciola hepatica, Dicrocoelium dendriticum, and hydatid cysts. Fifty samples were obtained from cattle without any parasitic infection as a control group. Serum levels of vitamin A, ß-carotene concentrations (µg/dL), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) activity were assayed. RESULTS: Naturally infected cattle with D. dendriticum, F. hepatica and hydatid cyst showed lower vitamin A levels. Serum ß-carotene levels were significantly decreased in all groups (p<0.05). ALT and AST activities in animals with parasitic diseases were statistically higher than in control group (p<0.01). A significant negative correlation was determined between the ß-carotene, vitamin A levels and enzyme activities of the liver in all the three types of liver infections (p<0.001). CONCLUSIONS: This study indicated that serum levels of vitamin A and ß-carotene decline was present in cattle with liver parasite infection and vitamin supplements should be supplied.

Molecular determination of abundance of infection with Sarcocystis species in slaughtered sheep of Urmia, Iran.

Sarcocystis is one of the most prevalent parasites of domestic ruminants worldwide. This study was aimed to determine prevalence of Sarcocystis infection and molecular discrimination of Sarcocystis gigantea and Sarcocystis medusiformis infecting domestic sheep. Tissue samples from 638 sheep slaughtered at Urmia abattoir were randomly collected from February 2011 to January 2012. Genomic DNA extraction and polymerase chain reaction (PCR) was performed to amplify a 964 bp fragment of nuclear 18S rRNA gene. The PCR products were subjected to digestion with endonuclease MboII and/or MvaI for discriminating S. medusiformis and S. gigantea. Results indicated that the overall prevalence of Sarcocystis unspecified species was 36.83% (235/638) in which male (7.63%, 38/498) and female (35.00%, 49/140) sheep over 4 years-old had the highest prevalence. There was no significant difference between prevalence of macrosarcocysts and sex. Two macrosarcocysts forms were found as fat (27.90%, 178/638) and thin (8.93%, 57/638) in striated muscles. There was significant difference between frequency of macrosarcocysts and body distribution. Mixed infection with both fat and thin macrosarcocysts was also found in 11.13% (71/638) of infected sheep. There was no significant difference regarding the prevalence of mixed infection in both age classes. The PCR-RFLP patterns showed that fat sarcocysts were S. gigantea (29.31%, 187/638) and thin sarcocysts were S. medusiformis (7.52%, 48/638). It was concluded that ovine Sarcocystis infection was prevalent in Urmia and a combination of conventional methods and molecular study for sheep sarcocysts could be informative.

Effects of chitosan on hematological parameters and stress resistance in rainbow trout (Oncorhynchus mykiss).

The aim of our study was to evaluate the effects of chitosan as immune stimulator on some hematological parameters and stress resistance in rainbow trout. Nine hundred rainbow trout (with initial body weight of 25 ± 0.1 g) were obtained from a local farm and acclimated to the laboratory conditions for one week. After that fish were randomly divided into four groups in three replicates. Each group received chitosan in diet at four concentrations as 0 (Control), 0.25, 0.5 and 1 percent chitosan, respectively. The trial was conducted for 8 weeks then feeding with chitosan stopped for 3 weeks later and during this time all fish were feed by control diet. The sampling was conducted to assay the hematological parameters of all groups every two weeks. In this study we assayed the resistance of fish against some environmental stresses immediately after changing the diet to the control. The results showed that using 0.25 percent chitosan in trout diets had a significant effect (P < 0.05) on hematological indices and stress resistance of rainbow trout in comparison the control group. Serum glucose level was higher in all treatment than control without any significance difference (P < 0.05). Based on the obtained results it concluded that the adding chitosan at 0.25 percent into the diet could enhance the hematological parameters and resistance against some environmental stresses in rainbow trout.