In addition, antibody levels were heterogeneous (ranging from 0.20 to 1 1.49 ELISA S/values), having a decreasing value pattern in older sows. Open in a separate window Fig. and PCV2 antigen detection in foetal myocardium was carried out. Results Vaccinated sows showed significantly higher antibody levels compared to the non-vaccinated counterparts. PCV2 DNA was only recognized at farrowing in 2 (4.2%) non-vaccinated sows. Vaccinated sows experienced 1.3 more live-born piglets per litter at the second cycle than non-vaccinated counterparts. Piglets from vaccinated sows experienced significantly higher (+?12.7%) vitality score than the ones born from GW438014A non-vaccinated sows. No PCV2 compatible lesions neither PCV2 antigen were recognized in the tested foetal hearts. Conclusions The present study represents a first attempt to demonstrate that PCV2 sow vaccination may have a positive influence on prolificacy and vitality of the offspring inside a subclinical infected breeding herd. However, since reproductive results at farm level may be affected by a number of factors, further studies would be needed to confirm this association. Keywords: (PCV2), PCV2 subclinical illness (PCV2-SI), Vaccine effectiveness, Sow, Reproduction Background (PCV2) is definitely a small and ubiquitous single-stranded DNA disease with a great economic importance for the swine market [1]. This disease is definitely linked to a number of diseases collectively named Porcine circovirus diseases (PCVD) [2]. Among these, PCV2 offers been shown to be involved in reproductive disorders in sows such as return-to-oestrus, late term abortions and improved quantity of mummified, stillborn and non-viable piglets at birth [3C8], as well as early embryo mortality [7, 9]. With this context, PCV2 can be transmitted to the embryos as soon as they eliminate zona pellucida [10], to the foetus through the placenta [11] and to the new-born piglets by colostrum [12]. Under experimental conditions, some studies possess shown that illness of sows by both artificial insemination (AI) with PCV2-spiked semen or PCV2 inoculation can cause foetal illness and reproductive disorders [5, 13]. Moreover, foetal GW438014A infections and reproductive abnormalities have been reproduced by intrauterine inoculation of foetuses or GW438014A foetal liquids [14C16]. However, at farm level, it is feasible that a proportion of PCV2 effects on reproduction are linked to embryonic death [7, 10], which today is still beyond the diagnostic capacity. This overall scenario leads to the fact that medical and visible reproductive disease (PCV2-RD) attributed to PCV2, at field level, is definitely infrequent [6, 11, 17]. PCV2 vaccination GW438014A in sows prior to farrowing is focused on the safety of the offspring by antibody transfer through the colostrum. This strategy has resulted in prevention of PCV2-systemic disease (PCV2-SD) [18], decrease of viremia [19C21] and PCV2 cells load [22] in their progeny, and improvement of the average daily weight gain (ADWG) in subclinically infected finisher pigs [23]. Despite these facts, it has been shown that sow vaccination does not fully prevent PCV2 vertical transmission [24C27]. In contrast, influence of PCV2 sow vaccination on reproductive parameters has been poorly investigated. As for example, this type of problems has been tackled as a secondary goal and in a very limited quantity of sows (1-3 sows per group) in some experimental studies [24, 25, 27]. At farm level, this issue has only been assessed in two peer-reviewed studies: firstly in one farm suffering from PCV2-SD in growing pigs but without obvious reproductive problems (PCV2-SI scenario in the sow herd) [23] and, secondly, in one farm with PCV2-SD among weaners and severe reproductive GW438014A problems in sows [28]. Whereas in the first study no significant differences on the main reproductive parameters between CNOT4 treatments were detected, in the second one an improvement of all measured reproductive parameters were recorded. However, information about the effect of this vaccination strategy on reproductive parameters in a farm with neither reproductive nor PCV2-SD problems (scenario resembling a situation of most breeding herds) is usually missing in the peer-reviewed literature. Thus, the current work was aimed to evaluate the potential effects of sow vaccination against PCV2 on serological (ELISA), virological (quantitative PCR (qPCR)) and reproductive parameters during two consecutive reproductive cycles in a PCV2 subclinical contamination (PCV2-SI) scenario (PCV2 blood circulation in the breeding herd but absence of clinical reproductive problems). Methods Farm selection The study was conducted in a 1900-sow farm located in Catalonia (Spain). This farm worked with weekly farrowing batches in all-in/all-out management system. The vaccination program applied by routine included sow immunization against (PRRSV), and Piglets were vaccinated against and PCV2 at 5?days pre-weaning and at weaning, respectively. Weaning was performed at 3?weeks of age. Moreover,.
