Micromorphological studies of adult stages of Haematopinus asini (Equine sucking lice; Phthiraptera: Haematopinidae) with its eggs from donkeys (Equus asinus)

The present study was aimed to determine the ultra-morphological characters of sucking lice, Haematopinus asini of equine. During routine examination study of donkeys in Faculty of Veterinary Medicine, Cairo University; in September, 2017, the hairs of infested animals which had visible lice and its nits were combed with fine toothed comb. Lice and its nits (eggs) were subjected to identification process which was scanning electron microscope study. The equine lice eggs were oval in shape, and pearly white in color, measurement of eggs length and width were recorded. The adults male and female were brown in color, with whole length of female was 500 μm ± 0.2, while in male was 410μm ± 0.1. The head was conical in shape and composed of haustellum and labrum which was folded in several membranous. Several sensory structures were described. The thorax length was recorded. The three pairs of legs with its claws were similar in length. Each tibia composed from one strong claw and one thumb like spines with distotibial pad (pullvilli) and empodium which resembles the honeybees comb (pullvilli and empodium). The pullvilli had many sensory sensilla on its surface. Two mesothoracic spiracles present at two lateral sides in mesothorax and six similar spiracular openings in the abdomen which were described with its scales. The abdomen of the male and female were similar except for the genitalia. The nymphs resembles the adult typically but with small size. The whole length of different instars were ranged from 150 - 350 μm ± 0.7, but the genitalia was smaller than adult. All body parts were described in detailed using scanning electron microscope (SEM).