Topographic survey on Hypodermosis in slaughtered cows in Urmia slaughterhouse.

Bovine hypodermosis is a myiasis caused by larvae of Hypoderma bovis and H. lineatum which are commonly known as grubs. As different insecticide pour-on treatments and SC Ivermectin، which must be in direct contact with larvae، are used in larvae controlling programs، therefore، determining the exact topography of the most probable regions of larval presence is of great importance and it could help using less treatments [compounds]. In the present study which was carried out in 9 months in Urmia slaughterhouse، a total of 4078 inspected carcasses، 225 (5/52 %) were shown to be infested with larvae (84/88% H. bovis and 15/12% H. lineatum). The highest infestation rate was seen in the traditional husbandry system which was totally 56/44% (95. 27% H. bovis and 4. 73% H. lineatum) on the left half of the body، 44 % (85/85 % H. bovis and 14/15 % H. lineatum) on the right half of the body. In animals with a 3-4 body condition (B. C.)، the rate was 43/11 % (90/72 % H. bovis and 9/28 % H. lineatum). In longissimus dorsi muscle، the rate was 55/5 %. This study and studies like this seem to be a good help in devising control and treatment programs. Five percent of carcasses with Hypoderma larvae infestation means a low rate of infestation in Urmia. However، serious treatment and preventive measures must be taken against this disease.