Pipestone Approach to PRRS派普斯通应对PRRS的方法

Gordon Spronk 高登·思邦克Pipestone Veterinary Clinic普斯通兽医诊所Pipestone International Management派普斯通国际管理Leman China李曼中国October, 2013 2013年10月

Summary总结

• Basic PRRS concepts 基本PRRS概念

• Key assumptions 关键假设

• Pipestone Decision Approach派普斯通决策方法

• Pipestone Production Approach派普斯通生产方法

• China approach中国的做法

Basic Concepts 基本概念

• PRRS is very costly 猪蓝耳病是非常昂贵的:– Higher mortality 死亡率较高

– Lower ADG 较低日增重

– Lower FE 较低饲料转化率

– High cost of intervention 干预成本高

– Lower than expected financial performance as measured by group on cost based accounting 低于预期的按基于成本会计的财务表现

– PRRS cost US Swine Industry $664 M USD PRRS 让美国养猪业损失六亿六千四百万美元

2011 Holtkamp and Kliebenstein

Sow Farm PPRS Break母猪场PPRS发病

PRRS Groups ClosedPRRS 封群

Sow Farm PPRS Break母猪场PPRS发病

PRRS Groups ClosedPRRS封群

Sow Farm PPRS Break母猪场PPRS发病 PRRS Groups Closed

PRRS封群

Key assumptions 关键假设

• PRRS negative status at weaning is more valuable than PRRS + status 断奶期PRRS阴性状态比PRRS阳性更有价值;– US weaned pig market pays a premium of $1 to $4 per head for

PRRS negative pigs 美国断奶仔猪市场对每头PRRS阴性猪支付溢价1至4美元

– US weaned pig market discounts for PRRS positive pigs 美国断奶仔猪市场对PRRS阳性猪折价

– In some cases; no sale for PRRS + status 在某些情况下，PRRS阳性没有售路

• Risk of exposure determines intervention plan 感染的风险决定干预计划– Location 位置– Filtration 过滤– Vaccination 疫苗接种– Elimination 消除

More Key assumptions 更多关键假设• Vaccine does not prevent new PRRS infection 疫苗并不能防止新的PRRS感染

• Vaccine does improve performance 疫苗提高性能

• Vaccine may assist in elimination 疫苗可能有助于淸除– Shorter shedding time 缩短散毒时间

– Lower amount of virus shed 降低病毒排出量

• Elimination is better than “living with” PRRS virus in the weaned pig. 对断奶猪淸除优于带毒生存。

Wean to Finish Data断奶到育肥数据

Spronk, Pipestone, 2013

2012-2013二季度 PRRS阴性 PRRS阳性免疫 PRRS阳性 均值

平均市场体重

平均自由度

顶部百分比

淘汰百分比

死亡率

平均日增重

平均日采食量

产量％

瘦肉％

调整料比

Basic concepts 基本概念 :Funds spent preventing PRRS is more effective than treating PRRS PRRS预防方面的开支比治疗方面的更有效

Prevention costs 预防成本

• Sites in more remote (lower pig dense) area较偏远地区的（猪密度较低）猪场

• Filtration 过滤

• Biosecurity 生物安全

• Auditing 审核

• Sampling 采样

Intervention costs 干预成本

• Higher mortality 死亡率较高• Lower FCR 较低 料比• Lower ADG 较低日增重• Lower % tops较低顶部百分比• Animal Health costs 动物健康

费用• Lower productivity 较低的生产

力• Lower throughput 较低的生产

量

Pipestone PRRS Decision Tree派普斯通PRRS决策树

• Production decisions based on research 生产决策基于科研– Aerosol transmission data 空气传播数据

• Conclusion结论: the risk of PRRS aerosol transmission is real PRRS空气传播风险是真实的

• OVERALL PRODUCTION GOAL 总体生产目标:– Step 1 第1步: Weekly production of large groups of PRRS PCR

negative weaned pigs 每周生产大群的猪蓝耳病PCR阴性断奶仔猪

– Step 2第2步: W2F health decisions based on research and risk assessment 基于科研和风险评估的断奶到育肥健康决策 :

• if risk of PRRS infection in growth period LOW如果生长期PRRS感染风险低: maintain PRRS negative保持PRRS阴性

• if risk of PRRS infection in growth period is HIGH如果生长期PRRS感染风险高: vaccinate 预防接种

Pipestone Production approach派普斯通生产方法

Start all new sow farms PRRS negative 所有新母猪农场开始于PRRS阴性:

• Location 地点– away from pigs as far as possible尽量远离猪群

“you always get what your neighbors have 你邻场的疾病迟早会传到你的猪场”

• Farm production design农场生产设计: Breed to Wean配种到断奶

• On site Gilt Developer Unit (GDU) 现场后备母猪发育单元

• Stocked PRRS negative 库存PRRS阴性猪

Pipestone Production approach派普斯通生产方法

Start all new sow farms PRRS negative 所有新母猪农场开始于PRRS阴性:

• Location地点: away from pigs as far as possible尽量远离猪群

– “you eventually get what your neighbors have你邻场的疾病迟早会传到你的猪场”

• If LOW risk of PRRS introduction 如果低PRRS引入风险: no vaccine 无需疫苗

• If HIGH risk of PRRS introduction 如果高PRRS引入风险 : vaccinate 接种疫苗

• Keep PRRS out 抵挡PRRS的进入 : BIOSECURITY 生物安全

• BIOSECURITY 生物安全 =Keeping PRRS out抵挡 PRRS的进入

Pipestone Production approach派普斯通生产方法Keep PRRS out 抵挡PRRS的进入 :• Construct the farm to limit access 建设农场来限制与外界接触– Location 位置– Roads 道路– Quarantine facility for new gilts 新后备隔离设施

• All gilts from PRRS negative sources 所有后备来自PRRS阴性源– Test on arrival 抵达时测试– Quarantine 隔离– Retest 再测试

Pipestone Production approach 派普斯通生产方法Keep PRRS out抵挡PRRS的进入 :• Control 6 critical entry points控制6个关键的入侵点:1. Employees 员工2. Weaned pig shipment 断奶猪装运3. Cull sow shipment 淘汰母猪装运4. Dead animal removal 死亡动物移除5. Any fomite(任何污染物) : maintenance,

products, feed 维护，产品，饲料6. New gilts and semen to the farm到农场的新母猪

和精液

Pipestone Production approach派普斯通生产方法

Keep PRRS out抵挡PRRS的进入 :• Filter the farm 过滤农场

– Construction to prevent leaks 建设，以防止通漏

– Protocol to allow staff entry and animal exit 允许人员进入和动物离开的程序

– Maintenance to measure filter performance 维护以测量滤波的性能

– Monthly audits of protocol 每月审计流程

– Annual filter testing by independent lab 每年由独立实验室检测过滤设施

Pipestone Production approach派普斯通生产方法• If established sow farm becomes infected with

PRRS 如果建好的母猪场感染PRRS:– Immediately implement protocol to eliminate PRRS

from the farm 立即执行流程，以从农场消除猪蓝耳病

– Definition of Elimination 淸除的定义: 6 weeks of PRRS PCR negative sampling 6周的猪蓝耳病采样PCR阴性

• Common Elimination protocol 通用淸程序:– LOAD 装猪

– CLOSE 封群

– EXPOSE 感染

EXAMPLE PRRS ELIMINATION Protocol PRRS淸除流程范例

• LOAD 装猪– Fill gilt developer unit with as many gilts as possible 给后备母猪培育单元填充尽可能多的后备

• CLOSE封群– the farm to new entries for 250 days 封闭农场250天

• EXPOSE感染– Expose the current on site gilt population to resident

PRRS virus 用本场PRRS 病毒感染后备母猪

– This determines day 0 of the closure 这是封群的0天

在半数猪群中210 天的时间不足以达到稳定stability in ~ half of the herds

210 days

“210 days”

到达

TTN

P的猪群百分数

累计TTNP - 所有农场

整群接种后的周数

Results结果

• Median TTNP was 210 days 恢复到正常生产所需时间中值是210 天

– Ranging from 84 to 301 days从84天到301天不等

Take home messages学习与思考

1. Herds took longer to reach stability than expected.猪群达到稳定所需时间要比预期的长

Key intervention steps重点干预步骤

• On site GDU 场内后备母猪培育单元– – Gilt Delivery at 6 kg (weaning) 后备送来时6 kg （断奶）

– Verified status at delivery 接收时验证

• Established Biosecurity Protocol 已建立的生物安全程序– Written 书面上的

– Trained 培训过

– Audited 经审核的

– Updated as needed 视需要更新的

More key intervention steps更多关键干预步骤:• Audit biosecurity implementation审计生物安全执行情况

– Daily by on-site farm staff 每天由现场员工

– Weekly by Supervisor每周由主管人员

– Monthly 每月

• Auditor 审核人员

• Farm veterinarian 农场兽医

– During High PRRS season PRRS 高峰季节: increase awareness 提高警惕性

Challenges for China 中国的挑战

1. Airborne diseases are plentiful in China 经空气传播的疾病在中国很多– PRRSV 猪蓝耳病病毒– FMDV 口蹄疫病毒– PRV 伪狂犬病毒– HCV 猪瘟

2. Many production sites are Farrow to Finish 许多场地是从分娩到育肥

3. Many Nursery /Finishing sites are large continuous flow sites. 许多保育/育肥场是大规模连续生产

4. Diagnostic sampling more difficult 诊断采样更加困难

Challenges for China中国的挑战

• Monitor your PRRS status 监控PRRS状态– Weaned pig 断奶猪

– Incoming gilts 新入后备母猪

– W2F sites 断奶到育肥场

• Sequence resident virus using ORF5 使用ORF5测序本场病毒

• Build database 建立数据库

• Measure results of your farm intervention plan 测量农场干预计划的效果

Summary总结• PRRS is costly 猪蓝耳病是昂贵的: US $664 M六亿六千

四百万美元• PRRS negative pigs more value than PRRS + pigs

PRRS阴性猪比PRRS 阳性猪更有价值• Start new farms PRRS negative and keep them PRRS

negative with good biosecurity. 新建PRRS阴性的农场，并通过良好的生物安全保持PRRS阴性

• Establish biosecurity protocols 建立生物安全流程• Train 培训

– Audit 审核– Measure 测量– Change 改变

• When a farm is infected with PRRS 当一个农场感染PRRS: Eliminate 淸除它