## 5 Mycobacteria Infection
### Animal Infection  
Regarding animal infections, there are similarities with the human counterpart, with mammals developing persistent cutaneous or subcutaneous nodules, fistulous draining tracts, and granulomas in soft tissues, mostly with localized disease [169; 276]. NTM infections seem to be mainly digestive, with primordial manifestation in intestinal mucosa and mesenteric lymph nodes, however, cutaneous and respiratory infection routes are also possible, namely by retro-bronchial and pulmonary routes, mainly due to dust inhalation during grazing in stablulation [169]. There is no proof of animal-to-animaltransmission. Several NTM species can be found in the microbiota of animals, namely rapid-growing NTM, with disease occurring opportunistically [169; 276]. Among the different species of NTM previously reported causing disease in animals are MAC, _M. kansasii_, _M. marinum_, _M. xenopi_, _M. chelonae_, _M. abscessus_, _M. fortuitum_, _M. smegmatis_, _M. phlei_, _M. porcinum_, _M. farinogenes_, _M. senegalense_, and _M. scrofulaccum_[169; 276]. Several MAC members have been reported to cause infection in livestock and wildlife species, for instance, dogs from the Basset hound dog breed that may develop systemic _M. avium_ disease [276]. MAC infection has been reported as the most common disseminated bacterial infection in rhesus macaques with the simian immunodeficiency virus [277]. _M. intracellular_ has been identified in a rusty monitor reptile with lung nodules and _M. avium_ was isolated from cockroaches from a South Taiwan hospital [278; 279]. In addition, several wild animals can become infected with MAC species, namely ruminants, lagomorphs, rodents, ungulates, carnivores, and several raptor species [280]. MAA is the main etiological agent of avian TB. Regarding MAP, the most commonly detected MAC member, several reports describe infection in cattle, sheep, and goat, as well as in wild ruminants, including red deer, roe deer, fallow deer, white-tailed deer, alpine ibex, and riverine buffalo. In non-ruminant animals, MAP was first detected in wild rabbits, brown bear, raccoon, opossum, coyote, red fox, stoat, weasel, wood mouse, European badger, European brown hare, jackdaw, and Egyptian mongoose, which may be exposed via feeding on contaminated grain, forage in pastures, feces, or predating on infected prey [280]. Transmission between wildlife and livestock occurs via fecal contamination of feed and forage, both in farm buildings and on pastures [281]. Once in the environment, MAP can survive for several years, being washed away by rainfall from contaminated pastures into rivers [282]. Published works suggest higher prevalence of MAP in Europe and North America, which also possible results from more research efforts [282]. The presence of _M. kansasii_ has been rarely reported from asymptomatic ungulates, pigs, dogs, and squirrel monkeys [283; 284; 285; 286]; from respiratory tract lymph nodes in cattle; and isolated from skin tissue as well [169]. _M. kansasii_ infection resulting in inflamed lymph nodes or pneumonia lesions has also been described in monkeys, llamas, goats, and domestic and feral pigs [285; 287; 288; 289]. Additionally, this bacterium has also been isolated from unpasteurized cow milk [290]. _M. marinum_ is mainly found in cultured, ornamental, and wild fish living in densely populated habitats, with water temperature and water quality being essential for infection development. Examples of commonly infected fish species include salmon, striped bass, turbot, tilapia, zebrafish, rabbitfish, and sturgeon [291; 292; 293; 294; 295; 296; 297]. The most commonly reported sources of infection in production fish are contaminated fish pellets produced from fish products. In addition to fish, several domestic animals and several wild animals (manatee, European hedgehog, bullfrog, and American toads) are reported as susceptible to _M. marinum_ infection [298; 299; 300; 301]. _M.