1,721,109 research outputs found
Risposta del test da carico del glucosio sul profilo metabolico e valutazione isto-patologica di campioni bioptici in bovine da latte nel periodo di transizione
Full text linkObjectives of this study were to determine effects of time relative to calving and health status on blood metabolite concentrations after glucose tolerance test (GTT) and to investigate on the severity and on the distribuition of periparturient fatty change liver (FCL).
Metabolic profiles were performed on plasma samples collected from 40 cows selected from 2 dairy farms. GTT and Blood sampling was carried out 7±5 d before and 7±5 d after the calving. Glucose was administrated intravenously in a 50% solution at a dose of 0,25 g/Kg. Blood samples were collected before (T0) and after the beginning of the test at different times (T2, T5, T10, T15, T20, T30, T40, T60, T80, T100, T120, T140, T160). Beta-Hydroxybutyrate (BHB), Non-Esterified Fatty Acids (NEFA), Glucose(Glu), Insuline (Ins), Aspartate Aminotransferase (AST-GOT), Alanine Transaminase (ALT-GTP), total proteins (TP), globulins(Gb), albumins(Alb) and Urea were analized. Histologic examinations by light microscopy and classifications of samples according to the severity of FCL and Inflammatory infiltrations were done.
The collected data were statistically analyzed by the analysis of variance (ANOVA), using SIGMA STAT 3.7 to evaluate the effect of the period (pre-partum and post-partum) and the farm (farm A and farm B) on the hematic, clinical and productive parameters.
Pearson’s coefficients were also calculated between the collected data; finally the AUC (Area Under Curve) of glucose, insulin, NEFA and BHB were calculated.
The result proved that in the post-partum period cows show insulin resistance that causes a reduction of the levels of glucose and insulin (P<0,005) and a consequent increase of the levels of NEFA and BHB(P<0,05); this mechanism permits to spare glucose (and so energy) for the mammary gland for the lactation. All the cows had mild or moderate FCL degree. Results show correlations between lipidic and inflammatory infiltration of hepatocites in prepartum and levels of NEFA and AST in postpartum. NEFA and AST activity are increased from the prepartum to the postpartum period. High levels of TP and Gb are present in both periods.
These data suggest statistically significant differences (P<0,05) between BHB, NEFA, AST and ALT and period.
NEFA and AST are parameters of diagnostic value, also if AST is not a liver specific enzyme. Finally it was also proved that there is a correlation between hematic parameters in the pre-partum and the pathologies of the first days of lactation; imbalances in the energetic metabolism during the pre-partum predispose to developing of clinical diseas
Optimization and comparison between two 6-DoF parallel kinematic machines for HIL simulations in wind tunnel
No full textParallel Robots are for sure the best choice for those applications in which a high accuracy and a high stiffness are required. As a matter of fact the closed-loop kinematic chains that characterize these machines guarantee a very low sensitivity of the end-effector position to the various sources of error. However the working volume of parallel kinematic machines is in general limited with respect to their dimensions. Moreover the reduced mobility range of the passive joints represents a critical aspect that cannot be underestimated. For these reasons PKMs should be optimized for the application they are meant.Given the specifications of the workspace that the machine should be able to cover, it’s necessary to identify an architecture that is suitable for this specific task. This paper describes the optimization process and the comparison between two candidates, the Hexaslide and the Gough-Stewart platform, in order to find out which one is the best choice for a task that requires to reproduce the hydrodynamic effect of sea waves at the bottom of scale models of off-shore wind turbines and boats during HIL simulations in the wind tunnel of the Politecnico di Milano
Purulent pericarditis from Arcanobacterium pyogenes in a bull [Pericardite purulenta da arcanobacterium pyogenes in un toro]
No full text
Kinematic synthesis of a new 3D printing solution
No full textLow-cost production of metal parts is a challenge nowadays in the Additive Manufacturing world and new methods are being developed. The MIM technique is an innovative approach for 3D printing. This method requires a machine with suitable kinematics capable of generating the adequate movements.
The object of this article is the kinematic synthesis of a 5Dofs robot, based on two PKM machines, for additive manufacturing in order to compliant with the requirements of this new technology. Robot kinematics have been optimized by genetic algorithm in order to cover the required workspace and the design of the robot and outline of the control system are also given
Monitoring Ketosis in dairy cattle: effect of two different therapeutic procedures on some metabolic parameters
No full textField application of ultrasound-guided biopsy of liver and perivisceral adipose tissue sampling in high production dairy cow
No full textLe ulcere gastriche nei camelidi sudamericani
No full textPatologie peculiari che caratterizzano i lamoidi ed in particolare gli alpaca sono le ulcere gastriche. Le ulcerazioni più comu- nemente riscontrate sono a livello di C-3 e vengono normalmente diagnosticate durante la necroscopia, considerando che nel- le gastriti primarie non si mettono in evidenza segni clinici specifici. La patologia ha eziopatogenesi in parte sconosciuta ed una incidenza non estremamente elevata. Considerando le probabili cause scatenanti la formazione di ulcere gastriche nei ca- melidi, la terapia non può che basarsi sull’utilizzo di farmaci soppressori della produzione acida dello stomaco: H2 antagoni- sti, gli H+/K+ ATPasi inibitori e gli analoghi delle prostaglandine. Sotto l’aspetto profilattico è necessario ridurre le cause pre- disponenti la malattia riducendo lo stress a cui questi animali possono essere sottoposti
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