**1. Introduction**

The productivity of the swine confinement has been steadily increasing in the last years. Ac‐ cording to data from [1], the largest producer of pork is China, which is responsible for pro‐ ducing 49.5 million tons and is followed by the European Union, United States and Brazil (22.5; 10.2 and 3.2 million tons, respectively). The increased productivity of the swine meat is mainly related to the use of technology in the genetics, nutrition, health and reproduction areas. The adoption of the artificial insemination (AI) in pigs from the 70-ies has been signif‐ icantly contributing to the development of swine production [2].

AI has contributed to the increase of animal production, since it accelerates the dissemina‐ tion of desirable characteristics from genetically superior animals. Worldwide, it is believed that 90% animals raised commercially are inseminated and this number is expected to fur‐ ther increase [3]. Thus, this biotechnology has been investigated in order to ensure best pro‐ duction indexes. These are supported by high rates of pregnancy and commercialization of the semen doses has been found, such as the creation of AI centrals in Denmark, Canada and Netherlands, which totalized exports to 35 countries in 2010.

The health issue and the difficulty of cryopreservation of the doses are considered as the main barriers to commercialization of doses from boar semen. Numerous studies have been carried out in order to develop efficient cryopreservation protocols, since this is the main method to ensure the maintenance of viable doses for a long period, as allowing for their transportation to long distances. Initially, the objective concerning AI was to obtain a better control over the sanitary conditions. However, it was noted that the considerable develop‐

© 2013 Pereira et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

ment of this biotechnology was not accompanied by scientific knowledge related to the transmission of diseases. On one hand, the use of the artificial insemination has the great ad‐ vantage in optimizing the use of the boar, whereas reducing the number of animals in the farm and consequently the costs of the management, medicines and animal acquisitions, the AI may function as a means diffusing pathogens, since there is no ideal sanitary control dur‐ ing the collection and manipulation of the semen. In this case, the AI using contaminated semen just maximizing spread of certain virus and bacteria since a single boar ejaculate can be used for insemination of various sows.

order to ensure that AI will not represent a risky factor for transmission of infectious diseas‐ es. Although there are wide variety of diseases that could contaminate the semen and conse‐ quently the inseminated female, the significance of a particular disease will vary according to epidemiological parameters and geographical localization of the farm. Even the risk for disease transmission is not the same in different countries of the world. Hence, the concept of pathogen-free centrals has become a common cause, since it is possible to obtain the pathogen-free semen either in countries that are free and in those that are not free from cer‐

The Potential for Infectious Disease Contamination During the Artificial Insemination Procedure in Swine

http://dx.doi.org/10.5772/52337

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tain disease, according to definition by World Organization for Animal Health (OIE).

adopted.

procedure.

Guérin and Pozzi, (2005) [6] suggested that diseases able to cause negative impact on AI can be evaluated according to health risk as follows: a) Diseases that were eradicated within a country or continent, such as the Classical Swine Fever in Brazil; b) diseases to which there is already an integrated program for control in AI, such as the CSFV or Aujeszky's disease, which implies a negative state of the donor boars; c) diseases that are considered as likely to be transmitted by AI, such as diseases associated with PCV2, PPV and transmissible gastro‐ enteritis, which are neither controlled nor associated with prophylactic measures routinely

The seminal contamination may be classified as extrinsic or intrinsic. The first case occurs when contamination occurs through an external source, such as feces or contaminated mate‐ rials used during semen collection or processing. The intrinsic contamination occurs due to viral infection that can be systemic or local, as occasioning viral elimination through testi‐ cles, accessory or preputial glands [6]. Thus, it can be indicated that the main risk points for contamination of the semen can occur at the semen collection stages, in semen manipulation,

Before the semen collection procedure, all utensils to be used and specially the material in contact with the semen must be sterilized according to routine hygienic procedures and equipments available at each AI station. The use of dry heat (ovens), moist heat (autoclave) and radiation (ultraviolet) are most suitable for sterilization. These materials include the col‐ lecting funnel and the collecting glass where the semen will be stored until the moment of dilution. Because accidents may occur during the collection procedure, it is advisable to build up a stock of sterile materials ready to be used in the case of contamination during the

The animal' prepuce is usually contaminated by a wide variety of infectious agents, as re‐ ported by some authors [7,8,11]. Thus, the occurrence of agents such as *Corynebacterium suis*, *Arcobacter spp.* and the Aujeszky's disease virus (ADV) in the ejaculate of the infected ani‐ mals becomes a real possibility to be considered. Therefore, the examination of the semendonor animals prior to collection of the semen is essential in order to ensure the sanitary quality of the semen. However, this previous evaluation may be not completely effective. This is due to the fact that certain viral agents, such as ADV which causes the Aujeszky's disease, have the peculiar ability to establish latency in the reproductive organs, therefore causing contamination of the semen although the animals remain serologically negative for those diseases [9]. Other viral agents such as PCV2 and PRRSV have a determinated sero‐ conversion period over which the agent will be eliminated through semen. Even when the

or in artificial insemination procedure according to sanitary conditions of the farm.

In this context, a considerable concern is assumed in relation to hygienic procedures in the semen manipulation process, especially in relation to semen destined for international mar‐ ket [3]. This fact is justified by the evidence of the possibility for transmission of some dis‐ eases via semen of swine. Among the possible agents that can transmit diseases are Aujeszky's disease virus, *classical swine fever virus* (CSFV), *african swine fever virus*, *porcine cir‐ covirus 2* (PCV2), *porcine reproductive and respiratory syndrome virus* (PRRSV), *porcine parvovi‐ rus* (PPV), *Chlamydia* sp., *Leptospira* sp, *Mycobacterium tuberculosis*, *Mycobacterium paratuberculosis* and *Brucella abortus* [4].

The effect from contamination of the boar´s semen may represent a considerable economical loss to the producer. This occurs because the presence of the bacterial or viral agents in the semen leads to the loss of fertility and reduction of the semen quality in male, and embryon‐ ic/fetal death, endometritis and systemic infection in the inseminated females, thereby con‐ tributing to reduction in the size of the litters.

Although the routine addition of antibiotics (ATB) in the seminal diluents may even elimi‐ nate a high number of contaminant bacteria, most viral agents still remain alive. Therefore, a concern has been assumed in relation to those pathogenic agents. Despite the availability of studies concerning to antivirus, these ones are still not used commercially due to ineffective‐ ness of the action, especially related to high toxicity to sperm cells. Thus, the main control criteria AI are limited to veterinary communication, inspection by health agencies and con‐ trol strategies such as vaccination, isolation and monitoring of animals [5]. Moreover, effi‐ cient routine tests for identification of contaminants in the semen samples still remain as a reality that is very far from the existent commercial farms.

Thus, this chapter aims to clarify some points referring to the potential for contamination by infectious agents during AI procedure in pigs, as well as to identify the main agents likely to be transmitted by this biotech, which can contribute to reduced fertility of the animals, be‐ sides the possible control measures that should be performed in order to reduce the dissemi‐ nation and effect of those pathogens on animals.
