The  paper  deals  with  the  results  of  investigation  differential  epidural  blockade  in  dogs  using  0.2%  and  0.25% 
bupivacaine  solution,  0.2%  and  0.375%  solution  ropivacaine.  Its  use  provides  for  an  autonomic  and  sensory  blockade 
component  in  the  absence  of  motor  blockade  component.  It  is  clinically  manifested  sympathetic  block,  analgesia,  and 
preservation of function of pelvic limbs. This effect is based by the anatomical structure of the peripheral nerve, consisting of 
different in structure and function of the fibers and the properties of some local anesthetics that can cause selective blockade 
of nerve fibers. 
The purpose and objectives of the study - the possibility of determining the flow and differential epidural blockade in the 
presence of sensory blockade without motor component bupivacaine 0.2% and 0.25%, ropivacaine 0.2% and  0.375%  in 
dogs. The material for the study were 9 dogs weighing 9-20 kg, body length of 56 to 89 cm.  
The based technique blockade was lumbosacral  epidural punction and epidural catheterization. Volume of local anes-
thetic  was calculated based on the length of the trunk of the body (0.5-0.7 ml per 10 cm from the back to the root of the tail) 
and body weight (0.35 ml per 1 kg). The first stage of the study was xylasine  sedation and catheterization of epidural space 
of the catheter tunneling deep in the tissues. The end of the catheter position at the fifth lumbar vertebra. The second stage 
was epidurals and determine its effects on the body. Standard solutions of bupivacaine and ropivacaine diluted to the desired 
concentration by adding to them  before use physiological sodium chloride solution. Options blockade recorded in the run 
after injections with an interval of 5 min for the first 90 minutes, then at intervals of 15 minutes to 420 minutes from the 
period of administration. 
Study  parameters  of  the  motor  block  was  performed  according  to    ataxia  scale:  0  -  no  ataxia;  1  -  asynchronous 
movements, ataxia barely noticeable; 2 - poor ataxia; 3 -  average  ataxia; 4 -  significant ataxia,  animal can  standing; 
5 - severe ataxia, animal can not stand. Options sensory component of pain blockade determined breakdown and registration 
options excitability of nerves in the area of anesthesia by nerve stimulation. Pain compression test performed by haemostatic 
forceps  interdigital  tissue  gap  and  characterized  three  states  -  the  complete  absence  of  pain  sensitivity,  partial  absence, 
presence  of  pain  sensitivity.  Options  excitability    determined  by  nerve  stimulation  Stimuplex  HNS  12  with  parameters 
0.3  ms,  1  Hz,  and  insulated  needles  are  positioned  at  a  depth  of  1  cm  of  anesthesia  area.  We  determined  the  minimum 
amperage, which caused a contraction of the muscles around the needle. 
Conclusions. 1. Epidural administration of bupivacaine 0.2% solution is pronounced and lasting effect of differential 
blockade in dogs. Motor and sensory components blockade manifested almost simultaneously, but the duration of the motor 
block is shorter than the sensory. The blockade is accompanied by S - shaped of thrunk, and most of the animals defecate 
phenomenon, indicating that increased peristalsis due to sympathetic block.  
2. Ropivacaine as 0.375% solution is causing pronounced effect of differential blockade in dogs that the term is shorter 
and less pronounced characterized component of motor blockade than bupivacaine 0.2% solution. 0.2% solution ropivacaine 
epidural  has less effect as sensory and motor blockade.  
3. The scheme determining motor and sensory components blockade in dogs by evaluating ataxia in points, pain and 
nerve stimulation test is objective and usable. 4. For clinical practice as a drug of choice for differential epidural blockade is 
the most appropriate solution 0.2% bupivacaine because it combines the enduring quality and low cost. Widespread use may 
be restricted by ropivacaine higher cost. 
Prospects for further research is the use of 0.2% bupivacaine solution of the differential blockade in dogs in a clinical 
setting. 
Key words: differential epidural block, bupivacaine, ropivacaine, motor and sensory blockade component, dogs, nerve 
stimulation.