Sarcoptes scabiei var.suis

猪疥蟎

第八组：

刘慧思

朱政怡、王雪洁、曾莉、程田

Introduction• Pathogen:

Sarcoptes scabiei var.suis

• Chronic dermatosis(慢性皮肤病 )

• Widespread

• It makes the skin itchy (发痒 )， rough(粗糙 ),scrap(落屑 ),chap(皲裂 ) and intolerably dirty (污秽不堪 ),so it is also called swine favus(猪癞 )。

• It significantly depresses grown rate and feed efficiency.

Morphology （ dioecism 雌雄异体）

• Egg ：• Oval （椭圆形）、 transpa

rent （透明的）、 150μm×100μm

• Larva （幼虫）：• Three pairs of feet

• Nymph （若虫）：• resemble the adult （类似

成虫）

• seta （刚毛）• clavula （小棘）• chewing mouthpart

（咀嚼式口器）

• Feet

• Handle （柄）

• Sucker （吸盘）

How to distinguish between male and female ？

• handle and sucker• （柄和吸盘）

Seta （刚毛）

famale maleLength ： 0.339~0.509mm 0.226~0.339mm

Width ： 0.283~0.358mm 0.169~0.243mm

hatching（孵化） in 3-4 days in the tunnel

Life cycle

molting （蜕皮） on the skin surface or in a pocket( 小穴 )

fertilization（受精） in the tunnel

The whole cycle: 2-3 weeks

Pathogenesis and Symptoms

• Site: head, ear back, bilateral trunk (躯干两侧 ) and

hind limb(后肢 ) all over the body

Skin irritation（刺激皮肤）

Gargalesthesia （痒感）

Inflammation（发炎）

Itching and rubbing（瘙痒）

Papule and bubble（丘疹和水泡）

Running sore（脓疮）

Pyogenic bacteria（化脓菌）

scab（结痂）

Thick,dry and chappy skin

（龟裂的）

Decreased appetite （食欲减退）

Emaciation（消瘦）

Pathogenesis and symptoms:

Itching and rubbing/scratching(瘙痒和摩擦 )

Papule and bubble（丘疹和水泡）

Haemorrhages and scab （出血和结痂）

Thick, dry and chappy（龟裂的） skin

Thickened skin and crusts(痂皮 ) in the ears

Epidemiology• Distribute all over the world . (Sarcoptes scabiei has bee

n reported in over 100 mammals, including humans.)• The mite spreads directly from pig to pig, either by close

skin contact or contact with recently contaminated surfaces.

• The boar( 公猪 ) helps to maintain infection in the herd( 畜群 )because he is constantly in direct skin contact with breeding females and he remains a chronic carrier( 长期带虫 ).

• Newly purchased pigs • There is a high potential risk  in the cold season.

Diagnosis This is confirmed by demonstrating the pres

ence of the mite. (Scarapings for microscopic examination)

Steps ：1 collection of scales

2 experimental method

Treatment and prevention