Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, USA.
Anim Health Res Rev. 2011 Jun;12(1):47-65. doi: 10.1017/S1466252311000053.
Porcine circovirus type 2 (PCV2) causes great economic losses in growing pigs and there are several reviews on disease manifestations and lesions associated with PCV2 in growing pigs. Reproductive failure in breeding herds, predominately associated with increased numbers of mummies and non-viable piglets at parturition, is one of the disease manifestations of PCV2 infection. Boars shed low amounts of infectious PCV2 in semen for extended time periods, and vertical transmission of PCV2 to fetuses during PCV2 viremia of the dam has been experimentally confirmed. However, intrauterine-infected piglets often are clinically normal. Nevertheless, pigs infected with PCV2 by the intrauterine route can be born viremic, possibly contributing to horizontal spread of PCV2 within the breeding herd and into the nursery. Shedding of PCV2 in semen and prevalence of intrauterine-infected piglets can both be greatly reduced by PCV2 vaccination well ahead of expected PCV2 exposure. This review is a discussion on current knowledge on the effects of PCV2 infection in the dam and in in utero fetuses, including clinical signs, lesions, diagnosis and prevention through vaccination. Infection of boars with PCV2, the potential for PCV2 transmission via semen and prevention of PCV2 shedding are also discussed.
猪圆环病毒 2 型（PCV2）会给生长猪带来巨大的经济损失，已有多篇关于生长猪 PCV2 相关疾病表现和病变的综述。繁殖母猪的繁殖失败主要与分娩时木乃伊胎和死胎数量增加有关，是 PCV2 感染的疾病表现之一。公猪在精液中会持续低水平排放有感染性的 PCV2，并且已通过实验证实 PCV2 可在母畜 PCV2 血症期间通过垂直传播感染胎儿。然而，经宫内感染的仔猪通常临床无症状。然而，通过宫内途径感染 PCV2 的猪可能会出现病毒血症，这可能有助于 PCV2 在繁殖群和保育舍中水平传播。通过 PCV2 疫苗接种，可在预期的 PCV2 暴露之前大大降低精液中 PCV2 的排放和经宫内感染的仔猪的流行率。本综述讨论了当前关于 PCV2 在母猪和宫内胎儿中感染的影响的知识，包括临床症状、病变、诊断和疫苗接种预防。还讨论了公猪感染 PCV2、精液中 PCV2 传播的可能性以及预防 PCV2 排放的措施。
