*3.2.5. Porcine circovirus 2*

Eradication through vaccination, removal of the infected animals and depopulation of the positive farms have achieved success in several countries [54]. However, care must be taken

The virus of the classical swine fever belongs to Pestvirus genus. It is highly contagious and causes the classical swine fever (CSF), with mortality rates ranging from 80 to 90% and leads to a framework of generalized bleedings. The contact with wild animals and infected food and the transit of animals are the main forms for CSFV dissemination. Therefore, the mar‐

In an experimental study, van Rijn et al [57] (2004) observed the presence of CSFV in pigs' semen at 3 days after infection. The elimination continued intermittently until the end of the experiment (18 days), as proving that artificial insemination can be a risk factor for transmis‐

Due to importance of the disease, the clinical suspicion should be investigated by laboratory techniques. While virus isolation is the gold standard, other tests such as ELISA and RT-PCR can be used for definitive diagnosis [58, 59]. The tonsils, spleen, pharyngeal and mesen‐

In the case of diagnostic confirmation, several procedures should be taken in order to pre‐ vent the virus from spreading through the region. The sacrifice of the positive animals, the prohibition that animals and semen to transit in the region as well as the installation of sani‐ tary barriers are actions for controlling the outbreak. Another control procedure is vaccina‐ tion, however only attenuated alive vaccines are available, as hampering the differentiation

The African swine fever virus is the causative agent of the african swine fever (ASF), that is a highly contagious and lethal disease characterized by a clinical picture similar to that of the classical swine fever [61, 62]. The epidemiological characteristics of the disease include the potential for rapid dissemination through direct and indirect contact as well as a natural

The virus of the African swine fever was isolated from the semen of infected pigs [6, 57]. The virus elimination through bodily secretions can last up to 70 days in persistently infected an‐

Besides the epidemiological importance, the persistently infected animals are the major ob‐ stacle to diagnosis because they present less severe clinical signs, as requiring confidential laboratory tests in order to establish a reliable definitive diagnosis of ASF as well as to pro‐ vide relevant information about the time of infection in order to successfully support the control and eradication programs [64]. The viral isolation is an important tool for diagnosis,

imals [63], which are the main villain in dissemination of the virus in herd.

with the wild pigs which are PRV reservoirs [55].

126 Success in Artificial Insemination - Quality of Semen and Diagnostics Employed

keting of semen for AI is considered an additional hazard [56].

teric ganglions are the favorite organs for sending to laboratories.

between vaccinated and infected animals [60].

transmission via arthropods and wild Suidae.

*3.2.4. African Swine Fever Virus (ASFV)*

*3.2.3. Classical swine fever virus (CSFV)*

sion of the disease.

The *porcine circovirus 2* (PCV2) is the causative agent of the porcine circovirosis and may present six different clinical syndromes, that are the multisystemic weakening syndrome (PMWS), dermatitis and nephropathy syndrome, the reproductive, respiratory, digestive and nervous failures [67, 68]. However, PMWS and the reproductive failures are only ones caused by PCV2 without the presence of cofactors [69].

In the aborted, stillbirths and/or mummified fetuses, the inflammatory changes can be ob‐ served in the myocardium associated with depletion of lymphoid tissues [69]. In those situa‐ tions, the probable infection source of the females is the contamination of the positive male' semen. Opriessnig et al. [70] (2006) demonstrated through IHC the presence of the virus in cells of the testis, epididymis and accessory glands.

Besides IHC, the PCV2 can be detected by hybridization in situ (HIS) and PCR [71]. The virus isolation can also be used. However, the virus produces no cytopathic effect in the cells, therefore it is necessary to detect the viral antigen by immunofluorescence or immu‐ nochemistry.

Recently, Blomqvist et al. [72] evaluated the reduction of the viral load in semen after single layer centrifugation followed by a swim-up. They observed a reduction higher than 99% in the semen samples. Furthermore, the commercial vaccines have been very effective for con‐ trolling the disease in infected herd.
