Characteristics of Lameness in Sheep:
In a paper by (Winter, 2008) she states that ‘’lameness is a common cause of welfare and economic concern in most sheep keeping countries’’. There are three common lameness problems caused by microbial organisms. These are interdigital dermatitis, Footrot and contagious ovine digital dermatitis (CODD).
Interdigital dermatitis: is a very common type of lameness in sheep. It can also be called Scald. It is caused by a bacterium known as Fusobacterium necrophorum. (Winter, 2008) explains how the effects of the bacterium are restricted to the interdigital skin located between the claws. It has been found to occur in sheep and lambs of all ages and is particularly common in growing lambs in spring and autumn. F. necrophorum are found in abundance in the environment and animal faeces. It favours a wet warm environment. Once affected the interdigital space appears moist, inflamed and red or grey in colour.
Footrot: is a secondary microbial infection after interdigital dermatitis has occurred. According to (Winter, 2008) another microbe known as Dicholiobacter noduses. This bacterium coupled with the F. necrophorum bacterium cause lesions to occur on the foot. The lesions that occur may reside solely in the interdigital space or the more severe cases may cause the horn to totally dethatch from the foot. According to (Egerton, 2007) the development of Footrot depends on the correlation of the host, the environment and the agent. This will decipher the severity, persistence and onset of the infection. Severity is also dependent on the strain of D. nodosus which infect the animal. The proteases produced by the bacterium and its fimbrae will decide the severity of the infection. In a study done by (Olse...
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...oint for infection and then spreads to the claws causing them to become sore and swollen. (Winter, 2004) explains how within a short period of time the pus builds up and exits the hoof out of the coronary band. Even after this happens the animal is likely to remain severely lame and the effected toes generally remain misshapen and swollen.
Granuloma: is another cause of lameness on farms. It is typically associated with over pairing of the hoof. It is not caused by a bacteria gaining entry to the hoof however the hoof may have been paired due to a bacterial infection and a granuloma resulted. In a study by (Winter, 2008) she locates granulomas to the front of the foot or toe. They are typically comprised of vascular outgrowths of granulation tissue. This exposed site on the foot can act a reservoir for D. noduses bacteria to reside and continue to infect the flock.