Zorana Kovačević

Biochemical parameters in rats with an applied model of sepsis (cecal ligation and puncture) with pure and mixed bacterial culture.

The goal of this work was to induce clinical sepsis in rats in order to measure the following biochemical parameters (glucoses, triglycerides, cholesterol, total proteins, albumins and creatinine). The experiments were done on 104 male Wistar rats, body weight 190 to 240 g. The rats were divided in four groups. Treated groups consisted of 28 animals while in the control groups there were 20 animals. Animals were observed and sacrificed at 12, 24, 72 and 120 hours after surgery. In this model of sepsis (cecal ligation and puncture - CLP) with pure and mixed bacterial cultures, significant changes were noticed in all biochemical parameters. Significant hypoglycemia, hypercholesterolemia, decreased concentration of urea and increased concentration of creatinine were found in the first half of the experiment in all groups of rats with sepsis (at 12 and 24 hours). Hyperproteinemia and hypotriglyceridemia reached statistically significant values at 24 h in the groups of rats in which sepsis was induced with pure bacteria culture. In the other half of the experiment significant hypoalbuminemia was found in all rats with sepsis (at 71 and 120 h). [Projekat Ministarstva nauke Republike Srbije, br. TR 31071]

Comparison of the Efficacy of Hydrogen Peroxide and Salt for Control of Fungal Infections on Brown Trout (Salmo trutta) Eggs

Background: Fungal infections can cause serious problems infecting fish eggs, especially unfertilized or dead eggs. In the past, this problem was solved by using very effective chemicals such as malachite green and formalin. But, due to its toxicity and carcinogenicity, malachite green was banned for use in fish intended for human consumption. Formalin also has been banned in most countries. Chemicals and drugs recommended for use to treat fungal infections are hydrogen peroxide, salt, potassium permanganate etc. The goal of the present study was to determine and compare the efficacy of antifungal effects of hydrogen peroxide and sodium chloride on brown trout eggs. Materials, Methods & Results: The experiment was conducted in the brown trout hatchery, Sipovo, Bosnia and Herzegovina. The experimental groups contained 500 and 1000 mg/L of hydrogen peroxide with 15 and 30 min of exposition; 1 and 2.5% of sodium chloride with 15 and 30 min of exposition and a negative control group (no chemical treatment). The treatment concentrations were calculated and prepared from hydrogen peroxide of 35% active ingredient, and sodium chloride (sterilized) of 100% active ingredient. Eggs for the study were spawned from 11 females and 4 males. The first treatment was performed on the fourth day, and each next treatment was performed at 3-day intervals. Six treatments were administered until the 19th day after the fertilization. The treatment of the eggs was provided until the eggs reached the eyed stage. The effectiveness of the chemical treatments was measured by a hatch rate. There was a significant difference between all treated groups and the negative control group (P < 0.05). Hydrogen peroxide with a concentration of 500 mg/L for 30 min was the most effective and demonstrated a higher hatching rate (75.7%). Sodium chloride treatments resulted in statistically significantly lower hatching rates than hydrogen peroxide treatments. The hatching rate in salt treatment with a concentration of 2.5% for 30 min was 27.3% lower than in hydrogen peroxide treatment with a concentration of 500 mg/L for 30 min. Discussion: Hydrogen peroxide is an effective antifungal, antibacterial and antiviral compound, and according to the Food and Drug Administration (FDA), hydrogen peroxide and salt are approved and classified as a low regulatory priority for the control of oomycetes on all species and life stages of fish. It is considered to be a very environmentally compatible chemical because it does not produce any toxic bioproducts when it decomposes. Hydrogen peroxide stood out as the best candidate substance for fungal control. The fact that the treatment with hydrogen peroxide at a concentration of 500 mg/L for 30 min was more effective than treatments at a concentration of 1000 mg/L can be explained by temperature dependency and treatment frequency of this chemical. Salt was not such an effective fungicide as hydrogen peroxide. When using salt, toxicity to the eggs should also be considered. Salt solutions may cause egg deaths at levels of 2.5% or higher. It is possible that high salinities have an inhibitory effect on the movement of fish embryo due to the high osmotic impact on the perivitelline layer. Thus, hydrogen peroxide has proven to be efficient, inexpensive, easy to use and environmentally safe in preventing fungal infections on brown trout eggs.

Hematological parameters in cows in early lactation treated with ketoprofen and their relationship with lipid mobilization and ketogenesis

Background: Dairy cows are exposed to numerous hematological and biochemical changes, what is bringing cows into the state of increased metabolic activity and physiological adaptations. These adaptive processes have resulted in increased lipid mobilization and ketogenesis with increased concentration of non-esterified fatty acids (NEFA) and beta-hydroxybutyrate (BHB). As a non steroidal anti-inflammatory drug, ketoprofen produces anti-inflammatory effects. The main objective of the present study was to found relationship between hematological parameters and ketoprofen administration and high lipid mobilization and ketogenesis in cows treated with ketoprofen immediately after calving. Materials, Methods & Results: Ketoprofen was used (3 mg/kg body weight) intramuscularly for three consecutive days post-partum on 15 cows of Holstein-Friesian breed. Cows of the control group (n = 15) were not treated with ketoprofen. Blood samples were collected at the day of calving, in the first and in the second week after parturition from the coccygeal vein of the both groups. Hematological parameters (erythrocytes, hemoglobin, neutrophils, lymphocytes and mean platelet volume) were determined on the automatic hematological counter. Metabolic parameters (NEFA, BHB) were determined by standard colorimetric kits using a semi-automatic biochemistry analyzer. Student’s t-test was used to determine the influence of the application of ketoprofen to the hematological parameters. The data analysis was performed using SPSS, version 19.0, software package for Microsoft Windows (IBM, Armonk, NY, USA). The results of comparison with (P < 0.05) were considered to represent statistically significant differences. Difference in correlation test between NEFA and BHB and other blood parameters in experimental and control group of cows were determined by the Fischer r-to-z transformation. The research results show that there was a increased red blood cell count and a higher concentration of hemoglobin (P < 0.05), fewer neutrophils (P < 0.01), lower number of lymphocytes (P < 0.01) and fewer mean platelet volume in cows that received ketoprofen after calving than those of the control. Determined hematological parameters and values of NEFA and BHB are in correlation. The correlation coefficients were significantly lower in the experimental group of cows. The intensity of the connection between hematological parameters and value of NEFA and BHB decreases. Discussion: It is well known that dairy cows with excessive adiposity manifest a low-grade inflammation and that elevated NEFA concentrations present positive risk factors for many proinflammatory diseases. Analyzing the results in this examination, it has been noticed that the increase of NEFA and BHB after calving were significantly lower in group of cows treated with ketoprofen. Also, determined hematological parameters and values of NEFA and BHB are in correlation. The intensity of these connection decreases in ketoprofen treated cows. In current study, in cows treated with ketoprofen there is decrease in concentrations of inflammatory mediators such as neutrophils and lymphocytes. Red blood cell and hemoglobin concentration decreased in the peripartal period as a result of inflammation. In cows treated with ketoprofen these concentrations increased. In many inflammatory conditions mean platelets volume is increased while there is a decrease in ketoprofen treated cows. Presented results indicate strong relationship between the concentration of NEFA, as well as BHB and hematological parameters indicating that the dependence of hematological parameters of intensity of lipid mobilization and ketogenesis was significantly lower in cows treated with ketoprofen immediately after calving.

Respiratory syndrome in calves in intensive breeding

Production of milk and meat on cattle farms is directly dependent on the performance of calves and their health status depends on the number of deaths and physical development at the stage of first insemination. The respiratory syndrome is the most important health disorder in calves and prevention of the occurrence of this syndrome has a decisive influence on successful breeding of calves. Since environmental factors have a significant influence on the occurrence of respiratory syndrome, the percentage of occurrence is higher at certain times of year when the weather conditions correspond to the occurrence of respiratory infections. This study evaluated the occurrence of respiratory syndrome during the year and in different categories of calves. It was found that respiratory syndrome usually occurs in spring and autumn months and most sick calves aged from 15 to 45 days.

Lesions existence on teat end in dairy cows

On two dairy cows farms Holstein-Friesian breed in South Backa district survey was conducted. A total of 82 cows were examined and 328 individual mammary complexes. The appearance of the teat end was assessed after milking by adspection method. From 328 examined mammary complexes, 209 (63.72%) were with changes on teat end, of which 71 (21.65%) papilla was with lesions at the top. 119 or 36.28% teat end of cows udders of were unchanged. Those results indicate the existence of various exogenous factors that may be detrimental to the structure to the papilla, which is considered the first line of defense udder.