Veterinary Research Forum

Abstract This study aimed to evaluate malondialdehyde (MDA) expressions using the immunohisto-chemical method in order to reveal the role of lipid peroxidation in the development and progression of hepatocellular carcinoma (HCC) induced by diethylnitrosamine (DEN) in male Wistar albino rats. Avidin-biotin-peroxidase method was used for immunohistochemical evaluation. Histopathological examinations revealed that DEN caused a mixed pattern (trabecular and acinar formations) of HCC in the majority of rats. The MDA positive stainings were significantly increased in rats in the HCC group compared to the healthy rats in the control group. In conclusion, this study data contain three important findings. The first one is that DEN triggers the formation of reactive oxygen species (ROS), excessively produced ROS cause oxidative stress, and as a result, oxidative stress strongly causes lipid peroxidation. Secondly, it is clear that there is an important relationship between oxidative stress-induced lipid peroxidation and HCC progression. At the same time, MDA is an useful biomarker in determining the prognosis of patients with HCC. The third and final finding is that intra-peritoneal DEN injection once a week for 20 weeks, but not in combination with other promoting chemical agents, appears to be very effective in inducing experimental HCC.

Abstract Aloe vera has been used worldwide in pharmaceutical, food and cosmetic industries due to the plethora of biological activities of its constituents. This study was done to evaluate the effects of dietary aloe vera on growth and lipid peroxidation in rainbow trout (Oncorhynchus mykiss). A total number of 480 O. mykiss (mean weight 9.50 ± 0.85 g) were randomized into four experimental groups including one control and three experimental groups that aloe vera was incorporated in their diet at 0.5, 1.0 and 2.0 g kg^-1. Trial was done for eight weeks. Then biometry and blood sampling were done. Plasma malondialdehyde, ferric reducing ability of plasma and growth index were estimated at the end of study. The results showed that aloe vera extract did not affect growth indices. Malondialdehyde was increased in the experimental group compared to the control group but ferric reducing ability of plasma showed a decrease in experimental groups (p < 0.05) compared to the control group. Our findings showed that dietary aloe vera have adverse effects on antioxidant defense system in O. mykiss.

Abstract The present study was carried out to examine the effects of a vitamin premix (VP) reduction or withdrawal from finisher diet (29-43 days) on performance, immuno-competence, and characteristics of leg bones and meat lipid oxidation of chickens fed on corn-soybean meal based diet. A total of 900 male broiler chickens (Ross 308) were allocated to five treatment groups (0, 33%, 66%, 100% and 133% VP), with nine replicates per treatment group. At 29 and 36 days of ages, four birds from each replicate were injected with sheep red blood cells (SRBC). The cell-mediated immunity was determined via phytohemagglutinin (PHA) and 1-chloro 2-4-dinitrobenzen (DNCB) at 34 and 42 days of ages. At 33, 38 and 43 days of age, 42 days of ages, and two birds of each replicate were slaughtered and bone parameters measured. The oxidative stability was evaluated by thiobarbituric acid reactive substances (TBARS) on the thigh samples that were stored for 90 day at -80 ˚C. The results showed that reduction or withdrawal of VP from diets at different time points of the finisher period did not affect performance, immunocompetence and characteristics of leg bones. Results of TBARS showed that lipid peroxidation of the treatment without VP was significantly higher than of the other treatments when slaughtered at 43 days of age. Finally, the results of this study demonstrated that it is not possible to reduce the VP in finisher broilers’ diets without negative effects on meat quality during the time of freezing.

Abstract The objective of this study was to evaluate effect of different concentrations of catalase in two extenders on motility, viability and lipid peroxidation bull spermatozoa during semen freezing process. Thirty ejaculates collected from ten Holstein bulls were pooled and evaluated at 37 °C. Pool ejaculated was split into two main experimental groups, 1 and 2. In experiment 1, specimen was diluted to a final concentration of 30 × 106 spermatozoa with citrate-egg yolk and in experiment 2; specimen was diluted with tris-egg yolk extender to the same concentration. In both experiments diluted semen was divided into three aliquots, including a control and two test groups. Each aliquot was rediluted with an equal volume of extender either without (control) or with one of the antioxidants contained one of the following antioxidants: catalase (CAT; 100 IU mL-1) catalase (CAT; 200 IU mL-1) and control group. No significant differences were observed in sperm viability and motility following addition of catalase enzyme at concentration of 100 IU mL-1 and 200 IU mL-1 to citrate-egg yolk extender. But the highest sperm viability was achieved by addition of 100 IU mL-1 and 200 IU mL-1 catalase to tris-egg yolk semen extender compared with the control group (P < 0.05). Malondialdehyde levels did not change with addition of catalase in both extenders compared with the control group. The obtained results provide a new approach to the cryopreservation of bull semen, and could positively contribute to intensive cattle production.