Clinical, bacteriological and therapeutic aspects of bovine mastitis caused by aerobic and anaerobic pathogens

Factors affecting the incidence and outcome of <i>Trueperella pyogenes</i> mastitis in cows

“…In these cases, the infection must be discovered even earlier. However, T. pyogenes mastitis often occurs in dry cows or immediately after parturition [18]. The infection may progress and cause considerable damage to the mammary tissue, because it is difficult to discover abnormalities in milk during the early stages of infection.…”

“…The pathogenesis of summer mastitis involves transmission of pathogenic bacteria by H. irritans , a species closely related to the housefly [3]. High rates of detection of anaerobic bacteria, such as P. indolicus and Fusobacterium necrophorum (along with T. pyogenes ), have also been reported [8, 18, 21]. In a survey of mastitis among heifers in Hokkaido, the disease occurred from May to October, with the greatest incidence in August.…”

“…In recent large-scale surveys, T. pyogenes has been identified as one of the main pathogenic bacteria causing mastitis in lactating cows [2, 4, 5]. Reported symptoms include high somatic cell count [16], notable reduction in milk yield [5], high rate of mammary gland dysfunction [18] and tendency toward culling [2, 6]. T. pyogenes mastitis causes immense damage to the dairy industry [1], and it is essential to reduce the extent of this damage.…”

“…An epidemiological feature of summer mastitis is transmission of the pathogenic bacteria by Hydrotaea irritans , an insect closely related to the housefly [3], and this is the reason that the disease onset commonly occurs during the summer [8, 21]. Summer mastitis is also caused by damage to the teat [18]. Hirvonen et al [9] reported a high recovery rate (40%) of summer mastitis if treatment starts at an early stage, but in general, the recovery rate is considered to be low [18, 22].…”

“…Summer mastitis is also caused by damage to the teat [18]. Hirvonen et al [9] reported a high recovery rate (40%) of summer mastitis if treatment starts at an early stage, but in general, the recovery rate is considered to be low [18, 22]. However, much is still unknown with regard to the occurrence of T. pyogenes mastitis in cows, as well as recovery and culling.…”