There seems to be two main types of pathogens that cause diseases in swine: those that are mainly introduced through direct pig contacts, and those that are often, and in some situations mainly introduced by indirect transmission means. In this review, the mange mite (Sarcoptes scabiei), toxigenic Pasteurella multocida and Brachyspira hyodysenteriae will be used as examples of the first type, and foot and mouth disease virus, Mycoplasma hyopneumoniae and porcine reproductive and respiratory syndrome (PRRS) virus as examples of the second. It is now clear from various epidemiological studies as well as experimental and field data that aerosol transmission of some swine pathogens plays an important role in their epidemiology. As previous biosecurity programs did not take this factor into consideration, it can at least partially explain why many of these programs suffered frequent failures and why air filtration is now becoming increasingly popular in North America. Identifying and quantifying transmission means should be a priority for every important infectious disease for which it has not been done.

We review the principles of ultraviolet (UV) irradiation, the inactivation of infectious agents by UV, and current applications for the control of microorganisms. In particular, wavelengths between 200 and 280 nm (germicidal UV) affect the double-bond stability of adjacent carbon atoms in molecules including pyrimidines, purines and flavin. Thus, UV inactivation of microorganisms results from the formation of dimers in RNA (uracil and cytosine) and DNA (thymine and cytosine). The classic application of UV irradiation is the inactivation of microorganisms in biological safety cabinets. In the food-processing industry, germicidal UV irradiation has shown potential for the surface disinfection of fresh-cut fruit and vegetables. UV treatment of water (potable and wastewater) is increasingly common because the process is effective against a wide range of microorganisms, overdose is not possible, chemical residues or by-products are avoided, and water quality is unaffected. UV has been used to reduce the concentration of airborne microorganisms in limited studies, but the technology will require further development if it is to gain wider application. For bioaerosols, the primary technical challenge is delivery of sufficient UV irradiation to large volumes of air, but the absence of UV inactivation constants for airborne pathogens under a range of environmental conditions (temperature, relative humidity) further compounds the problem.

Pork production began to flourish in the USA after the practice of finishing pigs on corn was popularized in the late 1600s. By the 1840s, there were 35 million pigs and 20 million people in the USA and Cincinnati was the world's largest pork market. Between 1890 and the present, the total number of pigs in the USA has remained at 50–60 million, but dramatic changes in swine husbandry over the course of the 20th century have metamorphosed pig production from small, extensive (outdoor), labor-dependent enterprises into large, intensive (indoor), capital-dependent, production systems. This development has led to debate concerning the impact of swine production on animal/human health, the environment, and the welfare of the animals under our care. In a very tangible way, the future of pork production depends on effectively addressing the public's concerns regarding animal welfare and health. Here, we review basic sensory and behavioral aspects of swine with the objective of reaching a better understanding of pig behavior and pig welfare. The premise of this discussion is that safeguarding animal welfare and health is good for pigs, pork producers and the animal-conscious public.

Persistent or difficult-to-treat Staphylococcus aureus infections in animals and humans may be related to small colony variants (SCVs) that can hide inside host cells and modulate host defenses. S. aureus SCVs have gained much attention in human medicine but have been underestimated and overlooked in veterinary medicine. Recently, an SCV isolated from a dairy cow with a history of chronic mastitis was shown to possess similar phenotypic and transcriptomic properties to those of human SCVs. SCVs form small, colorless, non-hemolytic colonies after 48 h, are only slowly coagulase positive, fail to ferment mannitol, and can revert to the parental phenotype. The phenotype of SCVs is mostly related to alterations in hemin and/or menadione biosynthesis or to thymidine deficiency. Transcriptomic analysis of SCVs shows up-regulation of genes involved in glycolytic and arginine–deiminase pathways, capsular biosynthesis; increased sigma B activity; and down-regulation of genes for α-hemolysin, coagulase and effector molecule RNA III of the global virulence regulator Agr. Similar results are reported at the protein level. SCVs are less virulent but successful persisters in infection models. SCVs persist longer and at higher numbers within non-phagocytes than do their parents. SCVs survive within spacious vacuoles up to 24 h within cultured bovine mammary epithelial cells, likely due to up-regulation of protective mechanisms that counteract the lethal acidic environment of the phagolysosome. Persistence of SCVs within host cells may explain failures in antimicrobial therapy and vaccinations.

Porcine circovirus type 2 (PCV2) causes great economic losses in growing pigs and there are several reviews on disease manifestations and lesions associated with PCV2 in growing pigs. Reproductive failure in breeding herds, predominately associated with increased numbers of mummies and non-viable piglets at parturition, is one of the disease manifestations of PCV2 infection. Boars shed low amounts of infectious PCV2 in semen for extended time periods, and vertical transmission of PCV2 to fetuses during PCV2 viremia of the dam has been experimentally confirmed. However, intrauterine-infected piglets often are clinically normal. Nevertheless, pigs infected with PCV2 by the intrauterine route can be born viremic, possibly contributing to horizontal spread of PCV2 within the breeding herd and into the nursery. Shedding of PCV2 in semen and prevalence of intrauterine-infected piglets can both be greatly reduced by PCV2 vaccination well ahead of expected PCV2 exposure. This review is a discussion on current knowledge on the effects of PCV2 infection in the dam and in in utero fetuses, including clinical signs, lesions, diagnosis and prevention through vaccination. Infection of boars with PCV2, the potential for PCV2 transmission via semen and prevention of PCV2 shedding are also discussed.

Hemorrhagic septicemia (HS), an acute, fatal and septicemic disease of cattle and buffaloes caused by Pasteurella multocida, is important in tropical regions of the world, especially in African and Asian countries. The prevalence of disease has been well documented with predominant isolation of P. multocida serotypes B:2 and E:2. Conventional methods of identification such as serotyping, biotyping, antibiogram determination and pathogenicity as well as molecular methods (P. multocida-specific polymerase chain reaction (PCR), a serogroup B-specific PCR assay, multiplex capsular typing system and loop-mediated isothermal amplification techniques) and characterization (restriction endonuclease analysis, randomly amplified polymorphic DNA analysis, repetitive extragenic palidromic PCR and enterobacterial repetitive intergenic consensus PCR analysis) are applied in parallel for rapid epidemiological investigations of HS outbreaks. Although several vaccine formulations including alum precipitated, oil adjuvant and multiple emulsion vaccines are commercially available, the quest for suitable broadly protective HS vaccines with long-lasting immunity is on the upsurge. Concurrently, attempts are being made to unravel the mysteries of the pathogen and its virulence factors, pathogenesis and determinants of protective immunity as well as diversity among strains of P. multocida. This review highlights the advances in these various aspects of HS.

Medium-chain fatty acids (MCFAs) are found at higher levels in milk lipids of many animal species and in the oil fraction of several plants, including coconuts, palm kernels and certain Cuphea species. Medium-chain triglycerides (MCTs) and fatty acids are efficiently absorbed and metabolized and are therefore used for piglet nutrition. They may provide instant energy and also have physiological benefits beyond their energetic value contributing to several findings of improved performance in piglet-feeding trials. MCTs are effectively hydrolyzed by gastric and pancreatic lipases in the newborn and suckling young, allowing rapid provision of energy for both enterocytes and intermediary hepatic metabolism. MCFAs affect the composition of the intestinal microbiota and have inhibitory effects on bacterial concentrations in the digesta, mainly on Salmonella and coliforms. However, most studies have been performed in vitro up to now and in vivo data in pigs are still scarce. Effects on the gut-associated and general immune function have been described in several animal species, but they have been less studied in pigs. The addition of up to 8% of a non-esterified MCFA mixture in feed has been described, but due to the sensory properties this can have a negative impact on feed intake. This may be overcome by using MCTs, allowing dietary inclusion rates up to 15%. Feeding sows with diets containing 15% MCTs resulted in a lower mortality of newborns and better development, particularly of underweight piglets. In conclusion, MCFAs and MCTs offer advantages for the improvement of energy supply and performance of piglets and may stabilize the intestinal microbiota, expanding the spectrum of feed additives supporting piglet health in the post-weaning period.

This paper identifies some of the more important diseases at the wildlife–livestock interface and the role wildlife plays in disease transmission. Domestic livestock, wildlife and humans share many similar pathogens. Pathogens of wild or domestic animal origin that can cause infections in humans are known as zoonotic organisms and the converse are termed as anthroponotic organisms. Seventy-seven percent of livestock pathogens and 91% of domestic carnivore pathogens are known to infect multiple hosts, including wildlife. Understanding this group of pathogens is critical to public health safety, because they infect a wide range of hosts and are most likely to emerge as novel causes of infection in humans and domestic animals. Diseases at the wildlife–livestock interface, particularly those that are zoonotic, must be an area of focus for public health programs and surveillance for emerging infectious diseases. Additionally, understanding wildlife and their role is a vital part of understanding the epidemiology and ecology of diseases. To do this, a multi-faceted approach combining capacity building and training, wildlife disease surveillance, wildlife–livestock interface and disease ecology studies, data and information sharing and outbreak investigation are needed.

During the first half of the twentieth century, widespread regulatory efforts to control cattle brucellosis due to Brucella abortus in the Union of Soviet Socialist Republics were essentially non-existent, and control was limited to selective test and slaughter of serologic agglutination reactors. By the 1950s, 2–3 million cattle were being vaccinated annually with the strain 19 vaccine, but because this vaccine induced strong, long-term titers on agglutination tests that interfered with identification of cattle infected with field strains of B. abortus, its use in cattle was discontinued in 1970. Soviet scientists then began a comprehensive program of research to identify vaccines with high immunogenicity, weak responses on agglutination tests and low pathogenicity in humans, as a foundation for widespread control of cattle brucellosis. While several new vaccines that induced weak or no responses on serologic agglutination tests were identified by experiments in guinea pigs and cattle, a large body of experimental and field studies suggested that the smooth–rough strain SR82 vaccine combined the desired weak agglutination test responses with comparatively higher efficacy against brucellosis. In 1974, prior to widespread use of strain SR82 vaccine, over 5300 cattle farms across the Russian Federation were known to be infected with B. abortus. By January 2008, only 68 cattle farms in 18 regions were known to be infected with B. abortus, and strain SR82 continues to be the most widely and successfully used vaccine in many regions of the Russian Federation.

The objective of this paper is to critically review and summarize available scientific and lay literature, and ongoing studies on human and porcine cysticercosis in Mozambique to identify knowledge gaps and direct immediate and long-term research efforts. Data on the spatial distribution and prevalence of the disease in human and swine populations are scarce and fragmented. Human serological studies have shown that 15–21% of apparently healthy adults were positive for cysticercosis antibodies or antigen, while in neuropsychiatric patients seroprevalence was as high as 51%. Slaughterhouse records indicate a countrywide occurrence of porcine cysticercosis, while studies have shown that 10–35% of pigs tested were seropositive for cysticercosis antibodies or antigen. Current research in Mozambique includes studies on the epidemiology, molecular biology, diagnosis and control of the disease. Future research efforts should be directed at better understanding the epidemiology of the disease in Mozambique, particularly risk factors for its occurrence and spread in human and swine populations, documenting the socio-economic impact of the disease, identifying critical control points and evaluating the feasibility and epidemiological impact of control measures and development of local level diagnostic tools for use in humans and swine.