Basic HTML Version
Molecular Microbiology Research (Online) 2012, Vol.2 No.1 1-9
ISSN 1027-5595
http://mmr.sophiapublisher.com
7
Table 5 Relationship between MIC and resistance to the drug
by Organisms, More MIC more resistance and vice versa
(B) Sulphonamides (Srivastava, 1998)
Pharmacokinetic studies of various sulpha drug
depicts maximum concentration (Cmax) of Sulpha-
dimidine, Sulphasomidine, Sulphaphenazole, Sulpha-
dimethoxyzine, and Sulphadiazine are 5.94, 1.55, 1.34,
0.96, 0.90 after 12 hrs of therapy @ 200mg/kg
through systemic route. Sharma and Gupta, 1980)
Milk to plasma ratio for Sulphadimidine and
Sulphamethoxypyridazine are 0.8 and 0.07 at the same
dose level of 4 gm IV (Table 6) (Srivastava et al.,
1998).
Table 6 Recovery free Sulphadimine in mastitic milk following
single IV admn (100 mg/kg)
(C) Tetracycline (Table 7)
Table 7 Pharmacokinetic profile of tetracycline group in
mastitis affected dairy cows
(D) Gentamicin
Recoveries of Gentamicin in infected quarters are
40-80% higher than normal one. Poor lipid solubility
limits parental application. 90% of Coliforms are
sensitive to Gentamicin therapy. Milk to plasma ultra
filtrate ratio is 0.95 (Anderson, 1999).
Table 8 Milk and plasma levels of Gentamicin in mastitic
buffaloes following single intra mammary at dose rate of 0.4
mg/kg
(E)Enrofloxacin
Enrofloxacin first time exclusively used for veterinary
practice having MIC >1µg/mL for Coli forms (Neer,
1998). It is detected in milk within 1 hour post
treatment and persists for 24 hours having five times
higher concentration than plasma (Pugliese et al.,
1991). Therapy at dose rate of 5 mg/kg body weight is
most effective and imparts >80% cure rates in
buffaloes (Table 9).
Table 9 Milk and plasma levels of Gentamicin in mastitic
buffaloes
9 Usage rationality
Effective therapy is a balance among detrimental
effects on the infectious agents andtoxic effects to the
host tissue.
Agent
MIC (µg/ml)
Resistance (%)
PEN
0.5
69.1
AMP
2
98.5
AMX
4
100
AMC
1
20.6
CLX
0.25
0
KAN
2.5
16.2
Agent
MIC (µg/mL)
Resistance (%)
PEN
0.5
69.1
AMP
2
98.5
AMX
4
100
AMC
1
20.6
CLX
0.25
0
KAN
2.5
16.2
Agents
Oxytetra-
cycline
Doxycy-
cline
Chlortetra-
cycline
Bioavailability (%)
80.8
85.4
78.9
MIC (µg/mL)
1.0
0.5
2.3
Cmax (µg/mL)
4.0
0.32
1.86
Tmax (h)
4
5.2
6.7
Vd (L/kg)
1.31±0.11 0.80±0.03 1.02±0.04
Half life (h)
10
9.8
7.5
ClB (Ml/kg/h)
1.02-1.45
1.07
2.75±0.17
Time after
admn. (h)
Plasma concen-
tration (µg/mL)
Milk concen-
tration (µg/mL)
0.5
0.38±0.009
5766.3±14.9
1
0.45±0.01
5566.8±2.84
2
058±0.007
2757.6±1.88
3
0.42±0.002
2167±1.88
6
0.88±0.008
1092±2.50
12
N.D.
3.06±0.02
24
N.D.
2.05±0.04
Time after
administration (h)
Plasma concen-
tration (µg/mL)
Milk concen-
tration (µg/mL)
0.5
1.28±0.02
309±4.21
1
1.60±0.02
750±9.64
2
1.40±0.03
482.2±1.24
3
1.32±0.01
48.3±0.69
6
1.24±0.01
23.7±0.61