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S Sankari

Publications and source records attributed to S Sankari.

At least 19 recordsLinked to original sources
PubMed2006

Temporal changes in concentrations of serum amyloid-A and haptoglobin and their associations with weight gain in neonatal reindeer calves.

Age-related changes in serum concentrations of two acute phase proteins (APPs), haptoglobin (Hp) and serum amyloid-A (SAA) were investigated in newborn reindeer calves. Repeated blood samples were obtained from 51 reindeer calves at ages 0-32 days (2-4 samples from each calf). An increase of SAA concentrations was observed during the first 2 weeks of life. However, by the end of the observation period, SAA concentrations had decreased to levels below those of the first week. Serum Hp concentrations increased throughout the observation period. SAA concentrations in the second week had a negative association with weight gain during the entire study period (4 months). These time-related changes in APP concentrations suggest that these proteins have a role in the defence and adaptation mechanisms of newborn reindeer calves. Possible reasons for these changes include the presence of APP mediators in the colostrum, exposure to environmental pathogens after birth and age-related changes in hepatic synthesis of APP.

Age Factors↗
PubMed2005

Effect of insemination volume on uterine contractions and inflammatory response and on elimination of semen in the mare uterus-scintigraphic and ultrasonographic studies.

The effect of artificial insemination (AI) volume on uterine contractility and inflammation and on elimination of semen in the reproductive tract of mares was examined for 4 h after AI using two methods, scintigraphy and ultrasonography. The same doses were used in both methods: 2 and 100 ml of skim milk-extended frozen semen. In the scintigraphic study, the number of reproductively normal mares was four per group and in the ultrasonographic study five per group. For scintigraphy, the semen was radiolabelled with technetium-99m. The static scintigrams were acquired immediately before and 30, 60, 120, 180 and 240 min after AI. The activities in the vagina and uterus were calculated and the values for sperm that had been discharged from the mare were obtained by subtracting the counts for the uterus and vagina from the total radioactivity. The dynamic scintigrams were taken continuously for the first 30 min after AI and in 5-min periods immediately after having acquired the static scintigrams. The uterine contractions were counted. In the ultrasonographic study, the mares were scanned before AI and at 5, 10, 15, 20, 25, 30, 60, 120, 150, 180, and 240 min after AI, for at least 1 min each time. The examinations were videotaped and contractions counted per minute. More contractions were observed with the ultrasonographic method than with the scintigraphic method. No difference was present in the number of contractions between the groups, except in the ultrasonographic study at 4 h, when the mares inseminated with 100 ml showed more contractions than did the mares inseminated with 2 ml. The intraluminal fluid was sampled with a tampon and by uterine lavage 4 h after AI in the ultrasonographic study. The numbers of polymorphonuclear leukocytes and spermatozoa were counted, but the differences between the groups were not significant. Under our experimental conditions and with the number of mares examined, the volume of the AI dose had an insignificant effect on contractility - with the exception at 4 h - and inflammatory reaction and on semen elimination in the uterus.

Animals↗
PubMed2004

Acute phase response in reindeer after challenge with Escherichia coli endotoxin.

The serum concentrations of two acute phase proteins (APPs), haptoglobin (Hp) and serum amyloid-A (SAA), were monitored in reindeer after challenge with endotoxin. Four adult female reindeer received either 0.1 microg/kg Escherichia coli 0111:B4 lipopolysaccharide B or saline solution intravenously. At the second challenge, the treatments were reversed. In addition to the APPs, changes in blood chemistry and rectal temperature were monitored. The endotoxin challenge caused a significant increase in SAA (peak 48 h) and a sharp decrease (8-12 h) of serum iron concentrations in all animals. The mean Hp concentration increased at 8 h and remained elevated until 48 h, but no statistically significant differences were found. This investigation demonstrates that challenge with a single-bolus dose of E. coli endotoxin can activate the acute phase response (APR) and SAA appears to be a more sensitive indicator of the APR than Hp during bacterial infection in reindeer.

Acute-Phase Reaction↗
PubMed2000

Clinical features of experimental trichinellosis in the raccoon dog (Nyctereutes procyonoides).

Three groups of six raccoon dogs (Nyctereutes procyonoides) were provided for the experiment: the first group was infected with pig-origin Trichinella spiralis, the second with raccoon dog-origin Trichinella nativa, and the third served as controls. Infection dose for both parasite species was 1000 larvae/kg of body weight, which led to intense final infection. Clinical signs, haematology and serum biochemistry with repeated blood samples were monitored up to 12 weeks post-infection. The most significant findings were a short-term eosinophilia in peripheral blood from the end of the first week post-infection until the end of the third week, loss of weight, and mild anaemia. In the early phase of the infection, the animals had gastrointestinal signs, loss of appetite and diarrhoea. No specific differences in clinical findings could be noticed between the groups infected with T. nativa and T. spiralis. In contrast to the symptoms reported in human outbreaks, fever was not observed in any of the infected animals and serum levels of muscle-specific enzymes did not change. No acute-phase response was observed in the enteral or parental phase of the infection. These findings indicate that because Trichinella spp. are very well adapted to the raccoon dog, it thus, could serve as the most crucial reservoir animal for sylvatic trichinellosis in Finland.

Animals↗
PubMed2000

The effects of a prolonged undernutrition on serum lipids and fatty acid composition of reindeer calves during winter and spring.

We examined the effects of undernutrition on lipid metabolism in reindeer (<1 year) during mid-winter and spring, with particular focus on the proportions of polyunsaturated fatty acids (PUFAs) in major serum lipids. The reindeer (n=8) were fed their winter feed, lichen, ad libitum for 5 weeks, followed by 40% restriction of energy for 8 weeks and refeeding to normal for 6 weeks. The concentrations of major serum lipids, cholesterol and phospholipids decreased significantly during the ad libitum period (by 50 and 44%, respectively). The proportion of major PUFA, linoleic acid in serum cholesteryl esters, decreased from 48.2 to 38.4% during the ad libitum period (P < 0.01), and to 29.2% during the restriction period (P < 0.001). The proportion of linoleic acid in phospholipids decreased from 27.9 to 15.6% during the ad libitum period (P < 0. 001), and to 13.0% during the restriction (P < 0.01). Also alpha-linolenic acid in the major lipids decreased significantly during the ad libitum and restriction periods. The decreases in the major lipids and linoleic acid were reversed during the refeeding. The control group (n=8) which was fed high-quality concentrates ad libitum gained weight most of the spring but showed similar although slower decreases in the major serum lipids and PUFAs than the lichen group. Our results indicate that feeding reindeer on lichen during winter leads to the retardation of growth and reductions in major serum lipids and their principal C18-PUFA proportions. The decreased proportions of the principal PUFAs most probably reflect their low dietary intake but may have been modified also by seasonal factors.

Animals↗
PubMed1999

Fumonisin B1-induced DNA damage in rat liver and spleen: effects of pretreatment with coenzyme Q10, L-carnitine, alpha-tocopherol and selenium.

Active oxygen radical species are reported to cause organ damage. This study was designed to determine whether oxidative stress contributed to the initiation or progression of hepatic and splenic cell DNA damage induced by fumonisin B1 (FB1) in rats. Another aim was to investigate the protective effects of the antioxidants coenzyme Q10 (CoQ10), L-carnitine, vitamin E (alpha-tocopherol) and selenium against DNA damage in the liver and spleen of rats treated with FB1. Fasted rats were injected intravenously with a single dose of fumonisin B1 at 1.55 mg kg-1 body wt. into the tail vein. Treatment with FB1 led to splenic and hepatic DNA fragmentation in 85% of the test animals. DNA fragmentation was investigated as a critical event in toxic cell death by testing total Ca2+ in liver. FB1 administration caused total Ca2+ in liver to increase within 4 h (204% of control). Measurement of liver enzyme activities showed an increase in aspartate aminotransferase (ASAT) and alanine aminotransferase (ALAT). FB1 also markedly decreased splenic and hepatic glutathione (GSH) levels. Pretreatment with CoQ10 (30 mg CoQ10 kg-1 diet) together with L-carnitine (2.8 mg carnitine kg-1 diet), alpha-tocopherol (30 IU vitamin E kg-1 diet) and selenium (1 mg selenium as sodium selenite kg-1 diet), decreased DNA damage and the activities of Ca2+, ASAT and ALAT in the liver. On the other hand, the level of GSH was slightly increased. The CoQ10 alone did not significantly protect against toxic cell death and glutathione depletion caused by FB1. Oxidative damage caused by FB1 may be one of the underlining mechanisms of FB1-induced cell injury and DNA damage.

Animals↗
PubMed1999

An experimental study on the effects of polymorphiasis in common eider ducklings.

Eight common eider (Somateria mollissima) ducklings were experimentally infected from 1 June through 13 June, 1995 with acanthocephalans (Polymorphus minutus) by allowing the birds to feed on Gammarus spp. (Gammarus oceanicus, G. salinus, G. zaddachi, and G. lacustris) containing acanthocephalan cystacanths. Uninfected Gammarus spp. were fed to a control group of seven ducklings. No mortality of ducklings occurred during the experiment. However, the infected ducklings gained weight more slowly than the control birds. After the 2 wk study period, the mean serum concentrations of total protein, albumin, beta-globulin, gamma-globulin, fructosamine and creatine kinase were lower in the infected group than in the controls. The mean (+/-SE) number of acanthocephalans in the intestine of the infected ducklings was 21 (+/-4). The parasites were attached to the mucosa of the posterior small intestine of the infected ducklings with a mixed inflammatory reaction consisting of heterophils and mononuclear lymphocytes surrounding the attachment sites.

Acanthocephala↗
PubMed1999

Effects of immobilization with medetomidine and reversal with atipamezole on blood chemistry of semi-domesticated reindeer (Rangifer tarandus tarandus L.) in autumn and late winter.

Blood chemistry was studied in 8 adult female reindeer, of which 5 were pregnant. Half of them received only medetomidine (150 micrograms/kg i.m.) and half of them medetomidine and atipamezole (750 micrograms/kg) in March. Three weeks later the drug regimens were reversed. The same procedure was carried out during the next September and October. Seasonal differences in pretreatment values could be seen in serum urea, phosphorous, and cholesterol, with the highest concentrations during the autumn; and creatinine, ASAT, ALAT, and CK values, which were higher in the non-pregnant reindeer in late winter. Their low-protein and low-energy diet during the winter explains most of the differences. Increased enzyme activities in serum indicate decreased membrane stability of certain organs in late winter, possibly due to nutritional deficiencies. Treatment effects could be seen in several parameters. The increase in blood glucose and decrease in serum FFA were most probably due to alpha 2-adrenoceptor activation, which inhibits insulin release and lipolysis. These effects were partly or totally inhibited after treatment with the antagonist atipamezole. The earlier increase in serum CK and ASAT activities in those receiving atipamezole can be explained by increased tissue perfusion due to atipamezole itself and the fact that these animals stood up and began to move much earlier than did those which received medetomidine only. A significant decrease in serum Na+, K+, Cl-, Pi, cholesterol, total Ca, and total protein concentration observed during the first 10 to 40 min of the medetomidine sedation could be explained by possible haemodilution and diuresis. More effective metabolism of medetomidine in autumn could explain the shorter recovery times of reindeer receiving only medetomidine and most of the differences in treatment effects between the seasons: faster increase in protein and cholesterol concentrations after the decrease, and the antagonistic effect of atipamezole on glucose and Pi changes in autumn. Based on these results, medetomidine seems to be a good sedation agent for reindeer both in autumn and in late winter; the effects of medetomidine can be rather effectively antagonized by atipamezole.

Adrenergic alpha-Agonists↗
PubMed1996

Quantitative determination of bovine serum haptoglobin in experimentally induced Escherichia coli mastitis.

A high performance liquid chromatography (HPLC) method was developed, validated and used to analyse haptoglobin concentrations in serum samples taken from eight cows which had been challenged twice intramammarily with Escherichia coli. The results of the HPLC were compared with those from a photometric assay. The kinetics of the haptoglobin response were analysed with pharmacokinetic computer software. In contrast with the photometric assay, the HPLC was sufficiently sensitive to detect normal background levels of bovine serum haptoglobin. The serum haptoglobin concentrations of healthy cows ranged from 22 to 47 mg litre-1. As the concentration of haptoglobin increased, the results of the two methods correlated well (r = 0.96). A 52-fold increase in serum haptoglobin was detected after the first challenge with E coli. The mean pharmacokinetic parameters of the response after the first challenge were: lag phase 12 hours, t2/1increase 20 hours, tmax 72 hours, t1/2decrease 46 hours, and mean residence time 112 hours. The second challenge three weeks later resulted in a significantly lower haptoglobin response, the area under curve being 35 per cent of that after the first challenge. The clinical signs and inflammatory changes in the milk did not differ significantly between the challenges.

Animals↗
PubMed1996

Effect of selenium fertilization on selenium in feedstuffs and selenium, vitamin E, and beta-carotene concentrations in blood of cattle.

Selenium (n = 56), total vitamin E, and homologues of natural vitamin E in feedstuffs (n = 52) and the concentrations of Se (n = 241), vitamin E (n = 244), and beta-carotene (n = 227) in blood were measured. The mean (+/- SD) Se content in hay, grass silage, oats, and barley produced using fertilizers enriched with Se was 0.13 (+/- 0.169), 0.17 (+/- 0.704), 0.23 (+/- 0.107) and 0.21 (+/- 0.119) mg/kg of DM, respectively, and the mean (+/- SD) vitamin E contents, calculated as dl-alpha-tocopherol acetate equivalents, were 39.7 (+/- 13.0), 120.0 (+/- 40.27), 24.4 (+/- 3.83) and 34.5 (+/- 3.57) IU/kg of DM, respectively. The mean Se concentrations in whole blood of cows, heifers, bulls and calves fed hay (n = 62), silage (n = 111), or pasture (n = 68) varied from 183 to 244 micrograms/l. The mean concentrations of total vitamin E in serum of lactating cows fed hay (n = 21), silage (n = 29) or pasture (n = 26) were 2.8 (+/- 1.43), 6.5 (+/- 3.03) and 8.2 (+/- 2.64) mg/l, respectively. For calves, concentrations of vitamin E in serum were as low as 0.25 mg/L. The mean concentration of beta-carotene in serum of lactating cows fed grass silage (n = 26) or pasture (n = 28) was 13.7 (+/- 6.61) and 15.4 (+/- 6.15) mg/L, respectively, but, in lactating cows fed hay (n = 20), concentrations were 2.5 (+/- 1.07) mg/L.

Animal Feed↗
PubMed1996

Blood selenium, vitamin E, vitamin A, and beta-carotene concentrations and udder health, fertility treatments, and fertility.

We investigated the activity of glutathione peroxidase in whole blood; concentrations of vitamin E, vitamin A, and beta-carotene in serum; SCC; udder bacterial infections and the incidence of clinical mastitis; fertility treatments; and the success of first AI of 511 dairy cows for 1 yr. The mean Se content in whole blood and the concentrations of vitamin E, vitamin A, and beta-carotene concentrations in serum were 191 micrograms/L, 5.9 mg/L, 0.39 mg/L, and 12.9 mg/L, respectively. An increase in Se concentration in whole blood was associated with a decrease in all infections, including infections by Staphylococcus aureus, Actinomyces pyogenes, and Corynebacterium spp. (-17.7, -31.7, and -70.6%, respectively). There was no association among the different infections or SCC and concentrations of vitamin E, vitamin A, or beta-carotene, but an association existed between vitamin A concentration and SCC. The lower Se concentration in whole blood did not increase incidence of clinical mastitis. The Se concentration in whole blood (200 micrograms/L) was accepted as a target value to optimize udder health. The incidence of fertility disorders (anestrus, subestrus, cystic ovaries, or delayed ovulation) was 34.4%. The pregnancy rate following first insemination was 48.6%. No significant association was observed among Se in whole blood; concentrations of total vitamin E, vitamin A, or beta-carotene in serum; and fertility disorders or success of first AI.

Animals↗
PubMed1996

Changes in inflammation-related blood constituents of mastitic cows.

The following blood constituents were measured in the blood and/or serum from healthy and mastitic cows: lipid peroxides (LPO), alkaline phosphatase (AP), lactate dehydrogenase (LDH), urea, glutathione peroxidase (GSH-Px), prostaglandin E2 (PGE2), cyclic AMP (cAMP), electrolytes (Na, K), white blood cells (WBC), haemoglobin (Hb), haematocrit, eosinophils, and electrical conductivity. The levels of these blood variables, excluding GSH-Px, erythrocytes variables and conductivity, were higher in mastitic than in healthy animals. In the blood of the mastitic animals, the AP and LPO levels were 44 and 38% higher than in the healthy animals. The substantial decline in the GSH-Px levels in mastitic animals (P < 0.05) may be related to changes in lipid peroxidation and PG formation and possibly to oxidative stress caused by the host defences. The eosinophil levels were positively correlated with those of PGE2 and cAMP. The possible implications of these findings for the diagnosis of mastitis are discussed.

Alkaline Phosphatase↗
PubMed1995

Comparisons of selenite and selenium yeast feed supplements on Se-incorporation, mastitis and leucocyte function in Se-deficient dairy cows.

The dairy cows at the Estonian Agricultural University appeared to have an extremely low selenium status. The selenium level was 5.6 micrograms/l in whole blood and 3.2 micrograms/l in milk, on average. The blood glutathione peroxidase was consequently extremely low. The effects of organic selenium (selenized yeast) and sodium selenite were compared in a feeding experiment on 100 dairy cows. Selenium incorporation, udder health and the in vitro function of blood neutrophils were monitored. Supplementation of the feed either with 0.2 ppm organic selenium or sodium selenite for 8 weeks, increased the blood selenium level (geometric mean) within this period from the back-ground level (about 5.6 micrograms/l) to 167 (Se-yeast) and to 91 micrograms/l (selenite). The respective change in whole blood glutathione peroxidase (GSH-PX) was from 0.22 to 3.0 (Se-yeast) and to 2.3 (selenite) microKat/g Hb. Blood GSH-PX continued to increase up to 10 weeks after the supplementation was stopped. The bioavailability of yeast selenium was superior to selenite: the relative bioavailability (selenite = 1) of yeast selenium was 1.4 if blood GSH-PX, 1.9 if blood selenium, and 2.7 if milk selenium was used as the response criterion. Selenium-supplementation showed a positive effect on udder health. The percentage of quarters harbouring mastitis pathogens dropped from 22.9 to 13.0 in the Se-yeast group and from 18.4 to 7.4 in the selenite group during the supplementation period. The effect of selenium on mastitis was also reflected as a decrease in the output of milk somatic cells and N-acetyl-beta-D-glucosaminidase (NAGase). The time-luminescence profile of zymosan-induced activity of blood neutrophils became skewed to the left in Se-supplemented cows.

Acetylglucosaminidase↗
PubMed1995

D-dimer improves the prognostic value of combined clinical and laboratory data in equine gastrointestinal colic.

The discriminating ability of 15 parameters alone or in combinations, including results from analysis of plasma endotoxin, the Nycomed plasma D-Dimer test and phospholipase A2, were analyzed to predict morbidity and mortality in equine gastrointestinal colic. Endotoxaemia was a characteristic feature of the colic horses. The problem of adequately predicting nonsurvivors among colic horses required several parameters to be included in the logistic model: if the "classical parameters", (heart rate, respiratory rate, PCV, anion gap) were included in the model, addition of plasma D-dimer, phospholipase A2, and Cl- significantly improved the predictive value of the logistic model. Increasing heart rate and D-dimer together with decreasing chloride was a risk factor for nonsurvival. The sensitivity of this three-parameter logistic model to predict nonsurvival was 78% and specificity 77%. The Nycomed D-Dimer test is recommended as a horse-site test to predict disseminated intravascular coagulation and nonsurvival in equine colic.

Animals↗
PubMed1994

Protective effect of antioxidants against free radical-mediated lipid peroxidation induced by DON or T-2 toxin.

An experiment was conducted on rats to investigate the capacity of antioxidants to protect against acute toxicity caused by DON or T-2 toxin. Male rats were fed two different feeds. One group received a feed deficient in vitamins C and E and selenium, whereas the other group was fed with a feed enriched in antioxidants. After two weeks, selected groups of rats were administered orally a single dose of DON or T-2 toxin. After the treatment with mycotoxins, all rats were decapitated. The livers were analyzed for TBARS values, hepatic GSH content and for the activities of CyP-450, CAT, SOD and GSH-TR. Increases in lipid peroxides of 21% and 268% were observed in those rats which did not receive the supplement of antioxidants and which were administered DON or T-2 toxin, respectively. There was no significant increases in the TBARS values in the groups receiving DON with selenium and vitamins, but increases of 57% and 79% were recorded in the groups administered T-2 toxin and antioxidants. Furthermore, in the groups fed the deficient feed and administered DON or T-2 toxin, the lipid peroxidation increased by 33% and 307%, respectively. No mortality, and a lower number of intoxicated animals were observed in rats fed a diet supplemented with antioxidants. Significant decreases of GSH, CAT, SOD, CyP-450 and GSH-TR were recorded in treated rats receiving the deficient feed. The results of this study demonstrate that trichothecenes stimulate lipid peroxidation with consequent decrease of GSH content, but that the dietary use of selenium, alpha-tocopherol and ascorbic acid provides protection against acute toxicosis caused by DON or T-2 toxin.

Animals↗