Fitzgerald Rose Mary, O'Shea Helen, Manzanilla Edgar García, Moriarty John, McGlynn Hugh, Calderón Díaz Julia Adriana
Bio-Explore, Department of Biological Sciences, Cork Institute of Technology, Rossa Avenue, Bishopstown, Cork, T12 P928, Ireland.
Pig Development Department, Teagasc Animal and Grassland Research and Innovation Centre, Moorepark, Fermoy, Co. Cork, P61 C996, Ireland.
Porcine Health Manag. 2020 Dec 8;6(1):34. doi: 10.1186/s40813-020-00173-z.
Serological screening is a common method to monitor antibody response to pathogen exposure, but results could vary due to several factors. This study aimed to quantify animal and management related factors associated with variation in antibody levels in finisher pigs at slaughter, in an Irish farrow-to-finish farm endemically infected with Actinobacillus pleuropneumonia (App), Mycoplasma hyopneumoniae (Mhyo) and swine influenza virus (SIV). A second objective was to estimate differences in antibody levels in pigs presenting pluck lesions. This was an observational study whereby pigs were managed as per routine farm practice. Data on sow parity, number of born alive (NBA) pigs per litter, cross-fostering status, birth and weaning body weight were recorded from 1016 pigs born from one farrowing batch. At slaughter, blood samples were collected for serological analysis and pigs were inspected for presence of enzootic pneumonia (EP)-like lesions, pleurisy, pericarditis and heart condemnations. Pigs were retrospectively classified into three production flows, depending on time spent in each production stage: flow 1 (F1; pigs followed the normal production flow); flow 2 (F2; pigs which were delayed by 1 week from advancing forward); and flow 3 (F3; pigs delayed by > 1 week from advancing forward). A nested case-control design was applied by matching pigs from each flow by sow parity, birth weight and NBA.
Pigs born from primiparous sows had higher antibody levels for App than those born to parity ≥5 sows (P < 0.05) and there was no association between any of the pathogens investigated and other early life indicators (P > 0.05). Pigs in F1 had lower antibody levels for App but higher antibody levels for SIV than F2 and F3 pigs (P < 0.05). There was no association between pluck lesions and respiratory pathogens (P > 0.05), except for increased antibody levels for Mhyo when EP-like lesions were present (P = 0.006).
Results indicate that offspring from primiparous sows develop higher antibody levels for App IV toxin when exposed to this disease and that enforcement of a strict all-in/all-out production system would reduce on-farm disease circulation. A high percentage of pigs were affected with EP-like lesions which were associated with higher antibody levels for Mhyo.
血清学筛查是监测病原体暴露后抗体反应的常用方法，但结果可能因多种因素而有所不同。本研究旨在量化与爱尔兰一个从仔猪到育肥猪的农场中屠宰时育肥猪抗体水平变化相关的动物和管理因素，该农场地方性感染胸膜肺炎放线杆菌（App）、猪肺炎支原体（Mhyo）和猪流感病毒（SIV）。第二个目标是估计出现内脏病变的猪的抗体水平差异。这是一项观察性研究，猪按照农场常规做法进行管理。记录了来自一批分娩的1016头仔猪的母猪胎次、每窝活产仔猪数（NBA）、交叉寄养情况、出生体重和断奶体重数据。在屠宰时，采集血样进行血清学分析，并检查猪是否存在地方性肺炎（EP）样病变、胸膜炎、心包炎和心脏病变。根据猪在每个生产阶段所花费的时间，将其回顾性地分为三种生产流程：流程1（F1；猪遵循正常生产流程）；流程2（F2；猪向前推进延迟1周）；流程3（F3；猪向前推进延迟超过1周）。采用嵌套病例对照设计，按母猪胎次、出生体重和NBA对每个流程的猪进行匹配。
初产母猪所生仔猪的App抗体水平高于胎次≥5的母猪所生仔猪（P<0.05），且所研究的任何病原体与其他早期生活指标之间均无关联（P>0.05）。F1流程的猪App抗体水平低于F2和F3流程的猪，但SIV抗体水平高于F2和F3流程的猪（P<0.
