Proteomic profile of histotroph during early embryo development in mares.

There is a complex cascade involving proteins during early embryo development and maternal recognition, which is very important for maintenance of a conceptus. The aim of this study was to compare proteomic profile of uterine fluid after ovulation in pregnant and cyclic mares. In the first cycle, samples of uterine fluid of 30 cyclic mares were collected on days 7 (n = 10), 10 (n = 10) and 13 (n = 10) post ovulation and constituted the Cyclic group. In the second cycle, the same mares were bred to a fertile stallion. At days 7, 10 and 13 uterine fluid samples were collected. Immediately after sample collection, the mare's uteri were flushed, and those with an embryo recovered were assigned to the Pregnant group. Of the 30 mares flushed embryos were recovered from 6 mares on day 7, 6 on day 10 and 6 on day 13. Samples from the mares without embryo recovery were excluded from both groups. The uterine fluid samples were processed by two-dimensional electrophoresis technique followed by matrix assisted laser desorption/ionization time-of-flight/time-of-flight (MALDI-TOF/TOF) mass spectrometry for the identification of relevant protein spots. From a total of 677 detected spots 19 were identified, 13 more abundant in Pregnant group and 6 in Cyclic group. In summary, pregnant and cyclic mares showed proteins with different abundance. Identified proteins were related to the transport of lipids through the embryo capsule, uterine motility, ATP generation, maternal immunological tolerance, cell proliferation, differentiation, metabolism and angiogenesis. Changes in the proteomic profile of uterine fluid during early embryo development in mares were related with the conceptus presence, suggesting that these alterations may be important for conceptus development and maternal recognition of pregnancy.

Porcine circovirus-2 viral load versus lesions in pigs: perspectives for post-weaning multisystemic wasting syndrome.

Porcine circovirus-2 (PCV-2) is the main agent related to post-weaning multisystemic wasting syndrome (PMWS) and it is also associated with other syndromes affecting pigs. Not all pigs infected with PCV-2 will develop PMWS and the incidence of PMWS is higher when coinfecting viral and bacterial pathogens are present. In this study, PCV-2 viral loads were evaluated in the tissues of animals with and without PMWS in order to investigate the relationship between viral load and microscopical lesions. Lymph nodes had the highest average viral load, but there was no significant difference between lesion severity and the viral load in these structures. There was no significant difference between the average viral load in inguinal lymph nodes of animals with and without PMWS. However, samples from pigs with PMWS had more severe lesions compared with samples from non-PMWS animals. These findings suggest that other infectious and non-infectious cofactors may be important in the pathogenesis of PMWS.

Classification and putative origins of Brazilian porcine circovirus 2 inferred through phylogenetic and phylogeographical approaches.

Porcine circovirus 2 (PCV2) is the major causative agent of postweaning multisystemic wasting syndrome (PMWS) and is associated with different syndromes affecting pigs. The PCV2 genome has three main open reading frames (ORFs) among which the ORF2 encodes the capsid protein. In this study, the ORF2 nucleotide sequences of 30 Brazilian isolates were analyzed. The sequences were compared to other GenBank sequences using phylogenic and phylogeographic approaches. Our results show high sequence variability in Brazil, since, in this work, the Brazilian isolates were classified into subgroup 1AB, 2D and 2, which reveals that the virus was introduced in Brazil more than once. On the other hand, most of Brazilian isolates seem to be derived from only one introduction. According to the data from the Pig Breeders' Association, the multiple introductions of the virus probably occurred through the import of animals with the asymptomatic form of the virus or through the import of contaminated semen. The results point to the necessity of implementing programs aimed at selecting sows in order to avoid the import of animals infected by Group 1 PCV2.