Branislava Belić

Relationship between the indexes of insulin resistance and metabolic status in dairy cows during early lactation

Abstract Insulin resistance is a phenomenon which accompanies the ongoing metabolic adaptation in cows during early lactation. The aim of our study was to determine the linear correlations of HOMA (Homeostatic Model Assessment), QUICKI (Quantitative Insulin Sensitivity Check Index) and RQUICKI (Revised Quantitative Insulin Sensitivity Check Index) indexes of insulin resistance with the metabolic status of cows (concentration of hormones, metabolites and body condition score). The experiment included 40 Holstein-Frisian cows in the first week after calving. Indexes of insulin resistance valued: 18.68±5.43 (HOMA), 0.39±0.06 (QUICKI) and 0.45±0.06 (RQUICKI). Linear correlations were examined by testing the coefficient of correlation (r), determination (r2,%) and regression parameter beta (b) in linear equation. A negative correlation was found between HOMA and IGF-I (insulin growth factor I) (r=−0.51, r2=25.0, b=−1.1257, p<0.01). HOMA showed a positive correlation with BHB (betahidroxybutyrate) (r=0.48, r2=23.2, b=0.0234, p<0.01). A positive correlation was found between QUICKI and IGF-I (r=0.30, r2=10.0 b=46.7900, p<0.05) and cholesterol (r=0.44, r2=18.3, b=1.9021, p<0.01). In contrast, QUICKI and BHB (r=0.51, r2=27.1, b=−1.7241, p<0.01), just like QUICKI and BCS (r=0.46, r2=20.9, b=−2.424, p<0.01), showed a negative correlation. RQUICKI showed positive correlations with IGF-I (r=0.48, r2=22.8, b=28.1230, p<0.01), T4 (r=0.47, r2=22.1, b=87.142, p<0.01) and triglycerides (r=0.36, r2=13, b=0.0407, p<0.05) but negative correlations with cortisol (r=−0.36, r2=13.0, b=−9.0332, p<0.05), STH (somatotropic hormone) (r=−0.42, r2=17.3, b=−5.4976, p<0.01), BHB (r=−0.62, r2=38.3, b=−1.1872, p<0.01), total bilirubin (r=−0.58, r2=33.7, b=−7.131, p<0.01) and BCS (body condition score) (r=−0.6, r2=36.4, b=−1.8347, p<0.01). In conclusion, indexes of insulin resistance may be used to evaluate the metabolic status of cows in early lactation. RQUICKI might be the most appropriate predictor of metabolic status due to its linear relationship with most of the parameters included in homeorhetic process.

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.

Influence of Blood Sample Hemolysis on Hematological and Biochemical Parameters in Cows During Early Lactation

Summary The aim of this study is to investigate the influence of hemolysis degrees on the values of hematological and biochemical parameters in the blood samples of cows in early lactation. The study included a total of 45 blood samples of cows in early lactation. Out of the total number of samples analyzed, 15 indicated no signs of hemolysis, whereas 15 indicated moderate hemolysis and 15 severe hemolysis. The influence of hemolysis was examined by determining the bias (%) and by means of the Wilcoxon signed-rank test. The results showed that the hemolyzed samples had decreased values of the HCT, RBC, MCV, and increased values of the MCH, MCHC, and PLT. The total number of LEU showed a declining trend with increasing degrees of hemolysis. The changes in the HGB values were not detected despite the visual identification. The hemolysis degrees showed a significant influence on the values of biochemical parameters. The variations in biochemical parameters were less significant in the samples with moderate hemolysis compared to the samples with severe hemolysis. The most hemolysis-sensitive biochemical parameters were the AST, TBIL, TGC, and NEFA as great variations of their values were found even in moderate hemolysis. A slight deviation was noted in the BHB and total protein values. With respect to all the parameters examined, the Wilcoxon test showed significant differences in the samples with moderate and severe hemolysis in comparison with the control group. In conclusion, hemolysis significantly influenced the values of hematological and biochemical parameters in the blood samples analyzed.

Investigations of significance of blood smear results in diagnostics of infectious and parasitic diseases in dogs

The microscopic examination of stained smears of peripheral blood is of vital significance in the speedy diagnostics of infectious and parasitic diseases, in particular during the stage of infection when the cause is present in the blood, or blood cells. It is sometimes possible to make a definitive diagnosis of an infectious or parasitic disease following an examination of a stained smear of the peripheral blood. Since microscopic examinations of a peripheral blood smear are applied increasingly rarely in clinical practice, due to the development of other methods for the diagnostics of infectious and parasitic diseases in dogs, as well as the lack of knowledge of the morphology of the numerous causes that can be present in the blood, we carried out an investigation into the presence and spread of infections whose causes can be present in dog blood. The investigations covered 100 dogs from which peripheral blood smears were taken and then stained with a Giemsa solution according to the standard protocol and examined under a microscope with an immersion lens. The examination of peripheral blood smears stained according to Giemsa resulted in the identification of the presence of an Ehrlichia spp. morula in a neutrophil granulocyte in one dog. The presence of hemotropic mycoplasmas was established in erythrocytes of eleven dogs, while the presence of the protozoa Babesia canis in erythrocytes was identified in five dogs included in the investigations. A microscopic examination of dog peripheral blood smears stained according to Giemsa was shown as a speedy, practical, simple, and inexpensive method for making a definitive etiological diagnosis of these infections, and it should be included regularly in standard protocols for the diagnostics of infectious and parasitic diseases.