Overview: Lowsonia Intracellularis in Pig and Horse

Lowsonia intracellularis is a Gram negative, obligate intra cellular, motile, anaerobic organism which resides in apical cytoplasm of enterocytes. It is one of the economically important pathogens in current pork industry in the world. Lowsonia intracellularis is an important pathogen in equine, also been reported in rodents, dogs, cats, foxes, sheep, deer, hamsters, rabbits, opossums, skunks, mice, coyote deer, ferrets, ostriches, and non-human primates.

Feco-oral rout of transmission occurs common Lowsonia intracellularis in livestock, companion animals and wild animals under natural conditions. Shedding of the organism is commenced on 7 days of post inoculation and excretion was observed until 12 weeks in infected animals. The clinical infection is called as porcine proliferative enteropathy (PPE) or |equine proliferative enteropathy (EPE) in pigs and horses respectively. The disease is characterized by thickening of mucosae in distal small intestine and proximal part of large intestine. Hyperplasia in enterocytes were the commonest histopathological finding in infected animals. Determination of Lowsonia intracellularis in feaces by qPCR and serological diagnosis are practised common in swine industry. Hypoproteinemia and hypoalbuminemia were significant finding in clinical pathology around 4 weeks before the onset of clinical infection. Gross pathology, histopathology, and immunohistochemistry are used widely in confirmatory diagnosis after the post-mortem examination.

Antimicrobial therapy and vaccination are two main methodology to control the infections in pigs and foals. Live attenuated and killed whole cell vaccine are widely used against Lowsonia intracellularis in pigs. Both cell mediated and humoral immune responses are required to eliminate the organism from body of animals. Minimizing stress factors, good bio security, continue screening of herd in endemic zones, early recognition of the disease are the important strategies in minimizing the clinical emergence of Lowsonia intracellularis. Screening, identification and culling of infected animals are recommended as part of the programme on minimizing unnecessary health burden in the industry.