Demodex mite disease is a chronic form, quietly pigs consume nutrients, thereby affecting the growth of pigs, pigs reduced the utilization of the feed, reducing the economic efficiency of pigs. But this process is often overlooked, and money slips away from the fingers.
Protozoal form
The worm body is slender and worm-like, translucent milky white, generally 0.17-0.44 mm in length and 0.045-0.065 mm in width. The whole body is divided into three parts: the corpus callosum, the foot body and the last body. The corpus callosum (fake head) has an irregular quadrilateral shape, consisting of a pair of fine needle-shaped cheeks, a pair of three-section limbs and one extending into a membrane-like structure. The composition of the lower mouth plate is a short-shaped sucking mouthpart. The foot (chest) has 4 pairs of short and thick feet. Each foot base and the abdominal wall of the body heal into a flat base piece, which cannot move. The other sections are sleeve-shaped, movable, telescopic, and there are a pair of anchors on the tarsal. Shaped claws. The end body (abdominal) is long and the surface has a distinct annular skin pattern. The male stem of the male protrudes from the back of the foot. The female's vulva is a long and narrow longitudinal split, located behind the fourth pair of feet on the ventral surface.
The Demodex is drilled into the sebaceous gland of the hair follicle, and the contents of the host cell are absorbed by a needle-shaped mouthpiece. Due to the mechanical stimulation of the insect body and the chemical stimulation of the excrement, the tissue has an inflammatory reaction, and the worm body continuously multiplies in the hair follicle. Causes the expansion and extension of the hair follicles and sebaceous glands, and even hypertrophy, causing hair shaft to fall off. In addition, due to the enlargement of the glandular opening, the insects enter and exit the activity, which easily causes the invasion of purulent bacteria and secondary to hairy adenitis and pustules. Some scholars believe that the hair follicle destruction and suppuration are a delayed type of allergic reaction according to the significant increase of lymphocytes and monocytes in the tissues invaded by the worms.
Clinical symptoms
Porcine Demodex mites usually occur around the eyes, at the nose and at the base of the ear, and then gradually spread to other parts. Itching is mild, or itching, and only white needles with needle tips, rice grains and even walnuts appear in the lesion. The capsule contains a lot of Demodex, epidermal debris and pus cells. When the bacterial infection is serious, it becomes a single small abscess and finally becomes a piece. Some pigs have thickened, unclean skin, uneven skin and dandruff, and wrinkles.
diagnosis
The early diagnosis of this pig disease is difficult. In case of suspicious circumstances, the nodules or pustules on the skin can be cut, and the contents are taken for smear microscopy to find the pathogen. Pig Demodex mites should be differentiated from sputum infection. The skin at the root of the disease is swollen, the skin is not red and swollen, the subcutaneous tissue is not thickened, the hair removal is not serious, the silvery white dandruff is sticky, and the itching is not serious. When rickets, the skin at the root of the hair is not swollen, the hair removal is severe, the skin is red and rash-like, but the subcutaneous tissue is not thickened, no white scales, but there is small jaundice, itching.
Popular characteristics: For contact with contagious hair follicles and sebaceous glands that occur first in the face of the pig's head, on the nose and on the neck side of the base of the ear, and then gradually spread to other parts.
Microscopic examination
Cut the white sac or pustule on the skin. The smear can be found in the smear microscopy. It is a long worm-like, translucent milky white, generally 0.25-0.3 mm in length and 0.04 mm wide; its head is irregular quadrilateral. There are four pairs of very short feet in the chest, the abdomen is long, and the surface has obvious horizontal stripes.
Preventive treatment
(1) Isolation and treatment of sick pigs, disinfection of contaminated sites and utensils.
(2) Ivermectin or avermectin 0.3 ml / kg body weight, once subcutaneous injection, repeated every 7-10 days, the effect is better.
Cemented Carbide Needle Rollers,Chrome Steel Needle Rollers,Stainless Steel Needle Rollers,Carbon Steel Needle Rollers
Qingdao Yukun Bearing Needle Roller Co.,Ltd. , https://www.ykneedleroller.com