جستجوی مقالات مرتبط با کلیدواژه « dexamethasone » در نشریات گروه « دامپزشکی »

The aim of this study was evaluation of cryo-viability of rooster semen supplemented with Rosemary and Fennel extracts in extender on quality of cryopreserved sperm under acute stress. A total of 24 roosters randomly divided into two groups: without stress (CON) or under oxidative stress, with administration of dexamethasone, 4 mg/Kg body weight, three times, every other day for 1 week, (DEX). Collected semen samples of birds were pooled in each groups and used in one of following treatments: 1) CON: with no extract supplementation or dexamethasone administration, 2) DEX: Dexamethasone group, 3) CON+Ros: semen of control group supplemented with 10 ml rosemary extract per deciliter of extender, 4) DEX+Ros; semen of DEX group supplemented with 10 ml rosemary extract per deciliter of extender, 5) CON+Fen: semen of control group supplemented with 6 ml fennel extract per deciliter of extender and 6) CON+Fen: semen of DEX group supplemented with 6 ml fennel extract per deciliter of extender. Results showed induced stress decreased sperm motility and biochemical parameters (P<0.05). Viability and membrane integrity of sperm were higher in CON+Ros and CON+Fen than other experimental groups (P<0.05). Similarly, supplementation of extender with rosemary and fennel extract in groups DEX+Fen and DEX+Ros improved mentioned parameters in rooster’s semen under physiologic stress. Totally, results showed supplementation of rosemary and fennel extract in cryopreservation extender can improve the quality of frozen-thawed semen in roosters reared under physiologic stress.

The aim of the current study was to determine the effects of different levels of milk thistle extract on productive performance, blood parameters and egg quality in laying hens imposed to dexamethasone-induced stress. The 2×3 factorial experiment was managed in a completely randomized design with 72 Hy- Line (W36) laying hens in 6 treatments and 4 replicates of 3 birds each. The experiment was carried out from the age of 75 to 81 weeks. Hens were weighed and either remained uninjected or received injections dexamethasone (0 and 4 mg per bird). The milk thistle extract were included at 0, 100 and 200 mg/kg in diets. The dexamethasone injections caused reductions in egg production percentage and egg mass in the throughout the experimental period (P<0.05). Laying hens imposed to dexamethasone-induced stress had the highest feed conversion ratio (P<0.05). The highest amount of lymphocytes in blood were observed in groups supplemented with 200 mg/kg of milk thistle extract (P<0.05). HDL content in serum was increased by the inclusion of milk thistle extract (200 mg/kg) (P<0.05). Adding of milk thistle extract to the diet of laying hens caused a significant decrease in LDL content in serum (P<0.05). In general, stress induced by dexamethasone injection reduced egg production and increased feed conversion ratio and addition of milk thistle extract to the diet had no positive impact on performance in laying hens.

Although numerous reports support the beneficial effects of supplementing chromium (Cr) on broiler performance under normal and stress conditions, the optimal level has not been determined yet.

This study was conducted to investigate the effects of different levels of supplemental Cr on performance, cortisol, and thyroid hormones of broiler under normal and stress conditions.

A total of four hundred forty-eight broilers were used. Broilers allocated into 2×4 factorial experiment included: stress (normal and stress) and 4 levels of supplemental chromium (0, 1000, 2000, 3000 ppb) since day 18. A completely randomized design with 8 treatments and 4 replicates (14 birds per replicate) was used. Dexamethasone used as a stressor for one week (stress period, STP) then experiment continued to day 46 (recovery period, RCP).

Feeding 1000 and 2000 ppb Cr improved feed conversion ratio (FCR) and increased T4 compared to 0 and 3000 ppb Cr in stressed broilers in STP (P<0.05). Feed intake (FI), body weight (BW) and T3 concentration were higher in broilers fed with 1000 ppb Cr in the diet and reared without stress in STP (P< 0.05). Despite the negative effect of stress on performance in RCP, dexamethasone-stressed broilers had better FCR. Feeding stressed birds with 1000 ppb Cr increased blood cortisol whereas it reduced cortisol in the normal-reared birds.

The Dietary supplementation of 1000 and 2000 ppb Cr reduced deleterious effects of physiological stress. Moreover, 1000 ppb Cr improved FI and BW of broilers under normal condition at first week. Feeding high level of chromium under normal and stress conditions did not improve the performance.

As ketamine hydrochloride and acepromazine is commonly used in anaesthesia of hamster and hypothermia isthe most dangerous side effect of this type of anaesthesia, it seems necessary to find a preventive method. Todayapplication of thermal pad as a physical method to increase body temperature is recommended in many referencesreferences. Thermal pad as a physical intermediate in increasing the body temperature has problems and complications, hyperthermia induced by continuous monitoring of the body temperature during anaesthesia, increasing thechance of bleeding from the surgical region and inability to sterilize thermal pads are among these side effects.In this study the effect of injection of dexamethasone was compared with thermal pad. So we provided 18 goldenmale hamster 6 month age with average weight of 150+_30 grams andThey were randomly divided into 3 groups. 1st group (control): body temperature without using dexamethasoneand thermal pad was recorded after anaesthesia. 2nd group (thermal pad): during induction of anaesthesia hamsters was placed on thermal pad. 3rd group (dexamethasone): simultaneously with injection of anaesthetic drugsdexamethasone was administered and body temperature was recorded after 10 minuets of induction of anaesthesia.Statistical study of data showed that the hypothermia diminished in the 3rd group slightly, but there is clear difference between body temperature before and after anaesthesia. In the 3rd group there was not a cleared differencebetween body temperature before and after the anaesthesia.

This study was conducted in order to evaluate the effect of dexamethasone on clinical healing and serum concentration of some biochemical parameters in dairy cows with LDA. 20 dairy cows with LDA were diagnosed and theywere divided into control (10 cows) and treatment groups (10 cows). Operation was carried out and antibiotic wasused in two groups and, in treatment group dexamethasone 0.5 mg.kg was injected once. All cows were examinedand their blood samples were drawn before and fve days after operation. The level of BHBA, ALT, AST, GGT andcalcium in serum samples were measured. After operation, the appetite and defecation returned to normal. In bothgroups, rumen movement increased that was signifcant in treatment group (P<0.05). In treatment group, beforeand after the operation mean serum level of BHBA were 1.24±0.07 and 0.88±0.06 mmol/l, glucose 29.22±2.66 and32.84±2.63 mg/dl, AST 127.57± 7.1 and 97.09±7.46 U/L, ALT 39.68=1.88.7.1 and 22.15±1.82. There was a signifcant difference between means (p= 0.001, p=0.005, p=0.002, p= 0.000, respectively). There was no signifcantdifference between GGT and Ca means. In control group there was no signifcant difference between means. Inconclusion, Injection of dexamothasone after the operation in cows with LDA increases serum level of glucose anddecrease BHBA and liver enzymes.