Larva of GEstrus Ovis in the Nasal Sinuses of Sheep. in 



In the worst cases the respiration becomes sighing, wheezing or 

 even snoring ; the mouth open ; head pendent ; appetite fails ; 

 a dull, apathetic condition ensues with grinding of the teeth roll- 

 ing of the eyes, and, rapidly advancing emaciation. 



Fatal cases are not uncommon but most frequently the larvae 

 reaching maturity are dropped and health is promptly re-estab- 

 lished. Septic poisoning from decomposition of dead larvae and 

 debris is a dangerous complication. 



Lesions. These consist in the presence of the larvae in the 

 sinuses, with violently congested, purple ulcerated mucous mem- 

 branes and collections of pus. The mere presence of the grub 

 is not conclusive as the majority of the sheep harbor two or three 

 from October to June. 



Treatment. It is advised to place the sheep in a warm building 

 to encourage the parasites to come out of their recesses and then 

 introduce some agent to destroy them or to induce their expul- 

 sion by sneezing. The value of the hot building is probably 

 hypothetical unless the larvae are approaching maturity. "The 

 following agents are used ; — ^moderately strong solutions of salt, 

 vinegar, carbolic acid, creosote (i part to loo parts of water), or 

 carbonate of ammonia, lime water, snuff, or even such irritants as 

 quick lime, oil of turpentine or hellebore. These last must be 

 used with caution as they are liable to induce fatal inflammation 

 of the air passages though no larva is present. 



By passing a feather up the nostril twisting it round and then 

 withdrawing it some grubs can usually be withdrawn and there 

 is no harm in first dipping the feather in some of the milder 

 agents mentioned above. But the larvae in the sinuses can never 

 be reached in this way. 



In dangerous cases it is best to trephine the outer plate of bone 

 covering the frontal sinuse and wash out freely with tepid water, 

 lime water, or benzine. The operation may .be performed close 

 in front of the root of the horn if there is one, or to the inner side 

 of the lower part of the eye if there is not. A semi-circular flap 

 of skin is to be turned upward and backward sufficiently large 

 to allow the use of a trephine \ inch in diameter, which is to be 

 used as for Coenurus Cerebralis. The opening being made the 

 sinuse is to be syringed freely for some time until the parasites 



