Diseases in swine transmitted by artificial insemination: An overview

Abstract

Artificial insemination (AI) of swine is widely practiced in countries with an intensive pig production. It is a very useful tool to introduce superior genes into sow herds, with minimal risk for disease transmission. However, the impact of semen that is contaminated with pathogens can be enormous. Most of the micro-organisms that have been detected in boar semen are considered non-pathogenic, but some are known pathogens (e.g. porcine reproductive and respiratory syndrome virus) that can cause major economic losses. Microbial contamination of semen can be due to systemic and/or urogenital tract infections of the boar, or can occur during collection, processing and storage. It can result in reduced semen quality, embryonic or fetal death, endometritis and systemic infection and/or disease in the recipient female. Conventional techniques for isolation of bacteria and viruses from the semen do not always provide optimal results for various reasons, including lack of sensitivity and speed of testing, and difficult interpretation of the outcome. More recently, PCR tests are commonly used; they have a high sensitivity, the outcome is quickly obtained, and they are suitable for monitoring a large number of samples. The best strategy to prevent AI-transmitted diseases is to use boars that are free of specific pathogens, to monitor the animals and semen regularly, and to maintain very high biosecurity. Additional measures should be directed at treating semen with appropriate antimicrobials, and at reducing contamination during semen collection, processing, and storage. #

Bacterial Contamination of Boar Semen and its Relationship to Sperm Quality Preserved in Commercial Extender Containing Gentamicin Sulfate

“…Many of the common bacterial genera found in boar semen are resistant to aminoglycosides, which are among the most common antibiotics found in semen extenders (Althouse et al 2000, Althouse and Lu 2005, Althouse 2008, Maes et al 2008. Our results are based on bacterial survival and proliferation (isolate frequency and changes in the level of total aerobic bacteria) and point to a selective pattern of bacterial growth in response to the bacteriostatic action of the single antibiotic in the extender.…”

“…Most microorganisms detected in boar ejaculates are considered (to some extent) nonpathogenic (Althouse et al 2000, Maes et al 2008, Morrell and Wallgren 2014, and they seem to have little effect on fecundity under natural mating conditions (Speck et al 2014), as the female reproductive tract has developed its own defense mechanisms to cope with bacteria from the semen (Dalin et al 2004, Morrell andWallgren 2011). However, when such semen is used in AI, there is a possibility that the bacteria will grow and multiply in the extended semen.…”

“…However, when such semen is used in AI, there is a possibility that the bacteria will grow and multiply in the extended semen. AI doses with bacterial overgrowth that are deposited in the female genital tract could contribute to an increase in postinsemination vulvar discharges or a regular return to estrus, as well as to embryonic or fetal death, endometritis, systemic infections, or disease in inseminated sows and gilts (Dalin et al 2004, Maes et al 2008, Morrell and Wallgren 2011, Goldberg et al 2013. Moreover, high levels of bacterial contamination have unfavorable effects on the sperm cells in extended semen (Althouse et al 2008, Kuster andAlthouse 2016).…”

14_Artificial Insemination and Its Role in Transmission of Swine Viruses

“…After experimental PRV infection by the intratesticular route, testicular degeneration and transient elevation in sperm abnormalities have been reported (Hall, Jr. et al, 1984a;Larsen et al, 1980). Sows inseminated with contaminated semen may develop vaginitis or endometritis resulting in embryonic death (Maes et al, 2008). Sows infected in the first trimester of pregnancy often reabsorb their fetuses and return to estrus.…”

Effect of threonine on immunity and reproductive performance of male mice infected with pseudorabies virus

“…The virus can be irregularly isolated either from urine, preputial membranes or semen (Medveczky and Szabo, 1981). Sows inseminated with PRV-contaminated semen show seroconversion, and may suffer -E-mail: pig2pig@sina.com from vaginitis, endometritis and embryonic mortality (Maes et al, 2008). Upon pathogen infection, toll-like receptors (TLRs), a highly conserved protein family, are innate pathogen recognition sensors.…”