Mastitis causes

Florfenicol (2) has been approved in Japan for the treatment of pseudo-tuberculosis caused by Pasteurellapiscicida and streptococcosis m. yeUowtail fish. The recommended dose is 10 mg/kg for up to one week and the drug withdrawal time is five days after cessation of treatment. Florfenicol is active in bovine respiratory disease caused by Pasteurella species and mastitis caused by Staphylococci and Streptococci. It is also effective in neonatal cohbacillosis caused by E. coli. The drug is being developed worldwide by Schering-Plough Animal Health for the treatment of aquatic and bovine diseases. 

Given the diversity of disease-causing organisms, the interactions between farm-specific environmental factors and the types of mastitis causing pathogens found, the potential efficacy of antibiotic treatments can only be assessed accurately in the context of the specific on-farm conditions. Furthermore, many recent investigations concluded that, except for some specific infections caused by streptococci, a prophylactic and or longer-term use of antibiotics for chronic and sub-clinical mastitis should not recommended in the future (Deluyker et al., 2005). 

Guterbock, W.M., Van Eenennaam, A.L., Anderson, R.J., Gardner, I.A., Cullor, J.S. and Holmberg, C.A. (1993), Efficacy of intramammary antibiotic therapy for treatment of clinical mastitis caused by environmental pathogens . Journal of Dairy Science, 76, 3437-3444. 

Bishop, J.G., Schanbacher, F.L., Ferguson, L.C., and Smith, L. 1976. In vitro growth inhibition of mastitis causing coliform bacteria by apo-lactoferrin and reversal of inhibition by citrate and high concentrations of apo-lactoferrin. Infect. Immun. 14, 911-918. 

Platenburg et al., 1994). While the former has limited effect on mastitis-causing organisms, no conclusive study on the efficacy of the latter is reported. 

Bliss, R.M. (2005). Transgenic cows resist mastitis-causing bacteria, www.ars.usda.gov/is/ pr/2005/050404.htm. 

Broadbent JR, Chou YC, Gillies K, Kondo JK. Nisin inhibits several gram-positive, mastitis-causing pathogens. J Dairy Sci 1989 72 3342-3345. 

Mastitis is well known to decrease lactose content. This fact explains the relation between lactose content and determination of log SCC (4). This emphasizes the possibilities of detecting changes with lactose when analyzing milk spectra and proves its strong relation with SCC. Factors 5, 6, 8 and 10, which showed high correlation with regression coefficients, had the highest correlation with protein content. This is consistent with the fact that mastitis causes alteration of protein fractions in milk. Mastitic milk has more proteolytic activity than normal milk, due to increase of proteinase plasmin, which hydrolyzes the casein (25, 26). Harmon (6) and Urech et al. (25), have reported decreased ccs-casein and (3-casein content and elevated whey proteins and y-casein in the total protein of mastitic milk. 

If untreated, mastitis can cause prolonged acute or chronic illness and low productivity and even death of dairy cows. However, recovery after shorter periods (days to weeks) have been more frequently observed, but since animal welfare considerations require sick animals to be treated, very few... 

The use of more selective antibiotics should be considered where diagnostic tests have accurately identified the disease-causing organism. Appropriate antibiotic therapy is complex and the reader is referred to relevant veterinary textbooks such as Andrews (2000) for a more detailed description. However, several important principles and approaches to antibiotic therapies used for mastitis are described below. 

However, in case of acute clinical mastitis, it is widely accepted that animal welfare considerations should take prevalence. If both farmer and veterinarian are not familiar with non-antibiotic treatments, they should be advised to use broad-spectrum antibiotics immediately, because any delay (e.g. the 2-3 days it often takes between diagnosis and the return of microbiological test results) may seriously harm the animal. This approach should, however, only be taken after a sound clinical diagnosis, since antibiotic treatments themselves may lead to dramatic aggravation of the condition. For example, E. coli inflammations are able to develop into severe toxaemia, because increased levels of toxins are released into the animal tissues when E. coli cells are killed or stressed by antibiotic treatments. Also, if yeasts are the main cause or form part of the pathogen complex that causes mastitis, their growth and proliferation may be supported by the administration of anti-bacterial antibiotics (Crawshaw et al., 2005). 

Mastitis is usually caused by Staphylococcus aureus, E coli, and Streptococcus. 

Mastitis is nearly always caused by bacterial infection. The introduction of benzyl penicillin for the treatment of intramammary infections (IMI) caused by Gram positive bacteria, followed by products containing other antimicrobial agents, was a major advance in... 

Mastitis is a complex of infections, caused by a variety of microorganisms with inherent differences in sensitivity to antimicrobial agents. Furthermore, sensitivity vitro does not assure efficacy vivo. Additionally, pathogens have the capacity to gain resistance to antibiotics, particularly under conditions of heavy and poorly controlled use. 

Inadequate recordkeeping and inadequate cow identification are among the common causes of failure to observe withdrawal periods. It specifically applies to milk after lactational or dry-cow intramammary infusions for therapy of mastitis, 491... 

Differences in the physiology and anatomy of the udder, the level of milk production, and the stage of lactation may sometimes be the cause of residue violations in milk. Failure to observe the proper withdrawal period after prophylactic and therapeutic use for mastitis might be simply due to some variation from the established milk-out rates (66). 

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