Effect of degree of lipomobilization on results of glucose test in dairy cows in heat stress

Cows exposed to heat stress exhibit a decreased ability to mobilize lipids due to increased sensitivity to insulin, which is expressed in a decreased concentration of NEFA. However, certain cows can preserve the level of lipid mobilization after adapting to heat stress. We assumed that cows that have a preserved ability to mobilize lipids are less sensitive to insulin and that they have a lower tolerance for glucose. The aim of this work was to compare the results of an intravenous glucose tolerance test in cows that exhibited, in prolonged heat stress, a decreased (NEFA<0.20 mmol/l) or preserved (NEFA>0.30 mmol/l) ability for lipid mobilization. Glucose concentration and NEFA concentration were measured following intravenous application of glucose. The mean glycaemic index value did not differ statistically significantly between the two groups of cows at 10, 15 and 20 minutes after glucose application (p>0.05), but there was a tendency at 10 and 15 minutes for the glycaemia to be higher in cows with preserved lipomobilization (p<0.1). At 30, 60 and 90 minutes after glucose application, glycaemia was statistically significantly higher (p<0.01; p<0.05 and p<0.05) in the group of cows with preserved lipomobilization. The glycaemic index values (mmol/l) shown in the same order (30, 60 and 90 minutes) were as follows 9.91±0.21: 9.23±0.41; 5.41±0.5: 4.67±0.33 and 4.31±0.39: 3.47±0.37. The mean value for NEFA concentration in samples originating from the two experimental groups of cows did not differ statistically significantly following glucose application. The NEFA concentration showed a tendency to be higher in cows with preserved lipid mobilization in comparison with cows with decreased lipomobilization at 20 and 30 minutes after glucose application (p<0.1). Following the intravenous glucose tolerance test, NEFA and glucose concentrations were in a significant negative correlation, and that correlation was more expressed in cows with decreased lipomobilization. Cows with preserved lipomobilization have a lower tolerance for glucose than cows with a decreased lipomobilization during heat stress. [Projekat Ministarstva nauke Republike Srbije, br. TR 31062

Metabolic acclimation to heat stress in farm housed Holstein cows with different body condition scores

The aim of this study was to determine the effects of body condition score to metabolic acclimation in heat stressed Holstein cows. Body condition of cows had no effect on any of the tested parameters during the thermal neutral period, except for the percentage of protein in milk. Heat stress has been demonstrated to have an impact on all the selected parameters, and has been found to be the cause of decreased milk production and quality, increased rectal temperature and respiration rate, decreased glucose, non esterified fatty acids (NEFA) and cholesterol concentration, increased urea and bilirubin concentration, and loss of subcutaneous fat. Obese cows (BCS&gt;4) had less ability of acclimation to heat stress as compared to normal and thin cows (significantly lower production and milk quality, and significantly higher rectal temperature and respiration level in relation to the other groups of cows). Obese cows showed a significantly higher concentration of NEFA and significantly lower glucose during exposure to heat stress. The steady increase in NEFA concentrations and decrease of backfat thickness suggested that fat was used for energy purposes, which significantly increased the heat balance and led to poor acclimation to heat stress in obese cows. Cows with high body condition were at higher risk of developing liver failure and lipidosis (reduced cholesterol and elevated bilirubin concentration) during heat stress, which could be linked with increased concentrations of fatty acids in the blood. This was found with an increased concentration of urea during exposure to heat stress, with significantly higher concentration in obese cows. Using the fat for energy purposes depends on the sensitivity to insulin, which increases during heat stress. Obese cows are naturally less sensitive to insulin and more prone to lipolysis. However, these signs should be the focus of future research.Key words: Body condition score, heat stress, metabolic status, cow

Relationship Between Endocrine Profile, Energy Balance and Milk Yield in Dairy Cows During Lactation

The objective of the present study was to investigate relationship between endocrine profile with energy balance (EB) and milk yield (MY) in Simmental dairy cows during lactation. Fifteen late pregnant cows, 15 early lactation cows and 15 mid lactation cows were chosen for the analysis. Blood samples were collected to measure growth hormone (GH), insulin, triiodothyronine (T3) and thyroxine (T4). Early lactation cows were found to have higher blood serum concentrations of GH (p0.05), T3 (p0.05) compared to dry and mid lactation cows. Insulin and thyroid hormones were in positive correlation with EB (p<0.05), and in negative correlation with MY (nonsignificant). GH was in positive correlation with MY (p<0.05), but in negative correlation with EB (nonsignificant). Relationship between hormones showed significant positive correlation between insulin and thyroid hormones. These relations are not principaly determinated by EB or MY. Negative correlations between insulin or thyroid hormones with GH were observed. These relations are principaly determinated by EB or MY

Prvi izveštaj o rasprostranjenosti i kliničkoj slici infekcije mačaka sa Bartonella henselae na području Novog Sada

Cat Scratch Disease (CSD) is an infective disease of animals and humans caused with Bartonella henselae. Prevalence of infection varies between 0 and 68% depending on different population of cats and geographical region. Naturally infected cats are often clinically healthy and are inapparent germ carriers. In this investigation 40 cats from the area of Novi Sad were analyzed. After the epidemiological questionnaire was made, all cats were clinically investigated. To determine the presence of specific antibodies of class G on Bartonella henselae the method of indirect immunofluorescence was used. For the first time in Serbia, in the area of Novi Sad municipality the infection caused by Bartonella henselae in the population of cats was detected. Prevalence of specific antibodies of class IgG on Bartonella henselae antigen in the population of cats was 57%. The most common clinical manifestations in seropositive cats were gingivitis and lymphoadenopathy.Bolest mačijeg ogreba (BMO) je infektivno oboljenje životinja i ljudi izazvano sa Bartonella henselae. Prevalencija infekcije varira u zavisnosti od populacije mačaka i geografskog regiona i kreće se od 0 do 68%. Prirodno inficirane mačke su često klinički zdrave, inaparentne kliconoše. U istraživanje je bilo uključeno 40 mačaka sa područja Novog Sada. Nakon uzimanja epidemiološke ankete, sve mačke su klinički pregledane. Za utvrđivanje prisustva specifičnih antitela klase G na antigene Bartonella henselae korišćen je test indirektne imunofluorescencije. Na geografskom području grada Novog Sada i okoline, po prvi put je u Republici Srbiji, utvrđeno prisustvo infekcije izazvane uzročnikom Bartonella henselae u populaciji mačaka. Prevalencija specifičnih antitela klase IgG na antigen Bartonella henselae u populaciji mačaka iznosila je 57%. Najčešće kliničke manifestacije kod seropozitivnih mačaka bile su gingivitis i limfadenopatija

Influence of body condition score and ultrasound-determined thickness of body fat deposit in holstein-friesian cows on the risk of lameness developing

The aim of this study was to examine the correlations between ultrasound measurement of thickness of fat over the tuber ischiadicum (TFT), body condition scoring (BCS) and the risk of lameness developing in Holstein-Friesian dairy cows. The 100 cows were enrolled from a population of dry cows on one farm. TFT was measured with ultrasound, and BCS and locomotion score were determined during lactation. Of the 100 cows, 31% developed lameness during lactation. The highest proportion of lame cows was in cows with BCS≥4.25 (66.7%). The risk of lameness developing was higher in cows with BCS≥4.25 (OR=7) and ≤3.25 (OR=2) than in cows with optimal BCS=3.75. Cows in the lower TFT quartile had a higher proportion of lameness, but not those in the upper quartile. TFT may have some value as a predictor of lameness in thin cows. The best prediction of lameness in both fat and thin cows (ROCAUC=0.8725, P<0.01) occurred when both BCS and TFT values were used together. The risk of developing lameness was positively correlated with BCS, negatively correlated with TFT and negatively correlated with their interaction. For fat cows, BCS assessment is a suitably strong predictor of lameness. In normal or thin cows, lameness prediction required the combination of both BCS and TFT measurements

HERNIJE KOD PRASADI U INTENZIVNOM UZGOJU SVINJA

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ZOONOZNI PATOGENI IZ ANIMALNOG OTPADA KAO FAKTOR RIZIKA ZA JAVNO ZDRAVLJE

Upravljanje animalnim otpadom iz stočarske proizvodnje prehrambene industrijezahteva bezbedna, ekonomski opravdana i praktična rešenja, koje su usaglašenasa propisima EU. Prema direktivi EC br. 17

Effects of niacin supplementation on the insulin resistance in holstein cows during early lactation

© 2017, University of Veterinary and Pharmaceutical Sciences. All rights reserved. Insulin resistance in early lactation includes low glucose concentration, low insulin release and responsiveness and high lipolysis. Niacin is important antilipolytic agent and leads to increase glucose and insulin concentration. The objectives of this study were to determine the influence of niacin on the insulin resistance in cows during early lactation using the difference of value and regression analysis between blood non-esterified fatty acid (NEFA), glucose and insulin concentrations, revised quantitative insulin sensitivity check index and glucose-to-insulin ratio. Niacin supplementation led to a decrease of NEFA concentration and an increase of glucose and insulin concentrations during the first three weeks after calving. Cows in the niacin group which were more resistant to insulin showed higher concentrations of non-esterified fatty acid in comparison with more sensitive cows from the same group, but still lower than the control. The regression analyses suggest the following characteristics of cows supplemented with niacin in comparison with the control group: the insulin response to glucose was more intense; the antilipolytic effect of insulin was lower; insulin efficiency expressed as glucose-to-insulin ratio increase with a decrease in NEFA. The metabolic changes due to niacin supplementation showed a dual influence on the insulin resistance in dairy cows during early lactation: decreased NEFA concentrations led to a decrease in the insulin resistance (due to an increase in insulin efficiency and insulin sensitivity index), but increased concentrations of insulin and glucose possibly caused an increase in the insulin resistance in dairy cows (due to lower insulin sensitivity index and possibly lower antilipolytic effects of insulin)

Inorganic phosphorus decrease after intravenous glucose tolerance test is associated with insulin resistance in dairy cows

© 2017, University of Zagreb, Facultty of Veterinary Medicine. All rights reserved. Inorganic phosphorus (Pi) concentration in blood decreases during an intravenous glucose tolerance test (IVGTT) due to the increase in the level of insulin and glucose. The objective of the present study was to determine the relationship between the intensity of Pi decrease with a dynamic change of insulin and glucose during IVGTT (AUC - total area under curve, AUC increment - area under curve from start of IVGTT to time of maximal response and glucose CR-clearance rate), as well as RQUICKI (Revised Quantitative Insulin Sensitivity Check Index) and RQUICKI-BHB (RQUICKI with beta hydroxybutyrate in formula) indexes of insulin resistance. The experiment included healthy and ketotic cows. Metabolic changes in ketotic cattle are similar to healthy cows in early lactation; ketosis represents impaired metabolic adaptation with higher insulin resistance. In both groups we found increases in insulin and glucose concentrations and Pi AUC during IVGTT, but these changes were less pronounced in the ketotic group. Ketotic cows showed a lower RQUICKI and RQUICKI-BHB index which indicates a higher level of insulin resistance. Pi AUC was in positive correlation with glucose response (glucose AUC), and this correlation is controlled with insulin response to glucose (insulin AUC). Pi AUC also showed a positive correlation with maximal glucose and insulin concentration during IVGTT, AUC and AUC increment for glucose and insulin, and glucose CR. These correlations were controlled by RQUICKI and RQUICKI-BHB indexes. The Pi decrease after the intravenous glucose tolerance test in dairy cows is associated with all aspects of insulin resistance, that include the insulin response to glucose (insulin AUC) and tissue response to insulin (RQUICKI and RQUICKI-BHB)