無乳鏈球菌乳房炎Streptococcus agalactiae Mastitis

ann

無乳鏈球菌乳房炎
Streptococcus agalactiae Mastitis


Prepared by: Dr. Terry Hunt


Translated by Dr. Ren Xiaoling
病因/發病機理

Cause & Pathogenesis
無乳鏈球菌—革蘭氏陽性球菌Streptococcus agalactiae – gram-positive cocci
·
高度傳染，專性奶牛乳腺寄生細菌
Highly contagious obligate inhabitant of mammary gland of cow

• 擠奶時牛—牛傳播
  Cow to cow transmission at milking
• 不侵入乳房組織，但損害上皮

Does not invade mammary tissue but does damage epithelium

危險因素

Risk Factors

• 帶菌牛只
  Carrier cows
• 不正確的擠奶程序
  Improper milking procedure

臨床癥狀
Clinical Findings

• 主要引起亞臨床性乳房炎Mainly causes sub-clinical mastitis
• 乳無可視變化
  No visible changes in the milk
• 所有乳房炎病例的90%是亞臨床性乳房炎（70%的經濟損失來自乳房炎）
• 90% of all cases of mastitis are sub-clinical (70% of financial loss from mastitis)
• 在所有的成年泌乳奶牛中，亞臨床性乳房炎是最昂貴的疾病
• Sub-clinical mastitis is the most expensive disease of adult dairy cows
• 體細胞計數高
  High Somatic Cell Count (SCC)
• 可偶爾發作成臨床性乳房炎May occasionally flare-up to clinical
• 體溫升高，食欲下降，精神萎靡，奶有變化

Elevated temperature, decreased appetite, depression and changes in the milk
診斷

Diagnosis·
根據SCC，臨床癥狀和乳的細菌培養
Based on SCC, clinical signs and milk culture
鑒別診斷

Differential Diagnosis

• 其他原因引起的乳房炎
  Other causes of mastitis

實驗室和病理學診斷Laboratory and Pathology
·
如果牛群有問題，大批乳桶的SCC升高
If herd problem, elevated bulk tank SCC
·
引起單個感染牛只的SCC顯著升高
Causes marked increase of SCC in individually infected cows
·
利用SCC鑒別感染牛，然后用CMT鑒別感染乳區
Utilize SCC to identify infected cows then use CMT to identify infected quarter

• 肯定感染乳區做細菌培養以區分其他鏈球菌和葡萄球菌

Culture infected quarter-must differentiate from other Streptococcus and Staphylococcus
治療

Treatment·
無乳鏈球菌對抗生素敏感，包括青霉素
Streptococcus agalactiae is sensitive to antibiotics including Penicillin
·
在泌乳期，用Blitz治療所有感染牛
Blitz treat all infected cows during lactation

預后情況


Prognosis·
治療有效的，預后良好，可從牛群中消滅
Good for response to treatment and elimination from the herd
預防

Prevention & Control
阻止傳播是基本的預防措施Stopping transmission is the basis of control擠奶程序和衛生設備
Milking Procedure and Sanitation

• 前浸泡

Pre-dip
2.
棄掉前幾把奶，檢查臨床性乳房炎（器具表面黑色最好）
Strip for clinical mastitis check (black surface best)

• 用一次性紙巾清洗和刺激乳房排乳

Clean and stimulate milk letdown with individual paper towels
4.
如果清洗，在洗液中加消毒劑
Disinfectant in wash solution if used
5.
只洗臟的奶牛，洗后必須完全擦干
Only wash dirty cows then must be thoroughly dried

• 擠奶員戴橡膠手套

Rubber gloves on milker

• 應用奶杯

Apply milking claw
從程序2至7應有60—90秒
Time from 2 to 7 should be 60 to 90 seconds

• 避免過度擠奶
  Avoid over-milking
• 浸泡乳頭可以傳送排乳信號

Teat dip post milking
·
檢驗并套上擠奶器
Test and maintain milking machines
·
在干乳期，每頭奶牛的每個乳區都要干燥
Dry cow treat every quarter of every cow at dry off
·
淘汰慢性感染牛只
Cull chronically infected cows
·
治療所有的臨床性乳房炎病例
Treat all cases of clinical mastitis
·
隔離所有的感染牛只及其牛乳
Isolate all infected cows and milk last
·
擠感染牛奶后，要消毒奶杯
Sterilize clusters after milking infected cows
·
保持一個封閉的牛群
Maintain a closed herd