RESUMO
Paratuberculosis (Johne´s disease) is a world-wide cattle disease caused by Mycobacterium avium subsp. paratuberculosis (MAP), associated with substantial economic losses. Purchase of subclinically infected animals or contact with animals and equipment of infected farms are known risk factors for disease transmission among herds. The aim of the present study was to identify specific management factors in Austria that triggered a MAP-positive herd status and to evaluate known risk factors for the transmission in cattle in small structured alpine agricultural systems. The agriculture in the Austrian province of Tyrol is characterized by smallholder structures, including shared alpine pastures and traditional barn management techniques. The data from an extensive survey with 50 questions in 2013/2014 and the development of the MAP herd status of 5592 cattle farms by taking feces and blood samples were examined and statistically evaluated. MAP herd status was determined by combining the results of boot swab samples, manure samples, pooled and individual feces samples as well as serological antibody testing by ELISA. The statistical analysis (odds ratio; OR) showed that the use of milk replacers for calf feeding (p = 0.047, OR=0.472) and the use of straw as bedding material for cows (p = 0.032, OR=0.625) were associated with a decreased chance of being a MAP-positive herd. Further, housing cows in deep litter systems (p = 0.028, OR=2.232), the presence of slurry channels (p = 0.028, OR=1.411) and the use of solid manure in young cattle (p = 0.041, OR=1.744) were associated with an increased OR for being MAP-positive. Surprisingly, sharing of lowland pastures (p = 0.564, OR=1.080), alpine pastures (p = 0.419, OR=1.143) or farm equipment (p = 0.733, OR=0.963) and farm size (p = 0.425) had no significant influence on the MAP herd status. The identified differences compared with previously published results in respect of MAP spread in cattle might be attributed to the traditional agricultural structures, including small family-based farms and common pasture during summer in alpine regions. Results of this study contribute to the understanding of the spread of MAP in cattle farming in alpine regions.
RESUMO
Inhibition of platelet function plays an important role in the treatment and secondary prevention of cardiovascular or cerebrovascular ischemic diseases. Established antiplatelet agents use different pharmacological targets for this role. Acetyl salicylic acid achieves a reduction of thromboxane A2 formation by inhibition of COX-1. Ticlopidine or clopidogrel are ADP-P2Y12 receptor antagonists. Tirofiban, abciximab or eptifibatid are used for the inhibition of the glycoprotein IIb/IIIa receptor which is activated at the surface of platelets preceding the final step of their aggregation. The mechanism of dipyridamole is based on the inhibition of adenosine uptake and of phosphodiesterase-5. Efforts are made to improve antiplatelet therapy with the aim to find agents with favorable clinical outcome and lower bleeding risk. Current clinical studies focus on a new generation of ADP receptor antagonists (prasugrel, cangrelor and ticagrelor) as successors of ticlopidine and clopidogrel after coronary arterial interventions. Developments using platelet targets different from established drugs are thrombin receptor antagonists (like SCH530348) or thromboxane receptor antagonists (like S18886/terutroban) in patients with cerebrovascular events. Results from recent experimental studies could lead to new strategies for antiplatelet therapy (like inhibition of GP Ib receptor, GP VI receptor, platelet-leukocyte interaction, factor XII and others) in the future.
