T. Goshen1,2, A. Shwimer1,3, S. Fridman3 and N.Y. Shpigel1,2
1Koret School of Veterinary Medicine, the Hebrew University, Beit Dagan, Israel.
2Hachaklait Veterinary Service. Gedera, Israel.
3National Service for Udder Health and Milk Quality. |
|
INTRODUCTION
Mastitis is the most important disease economically in dairy farms (11, 13). Mastitis can be divided into clinical and sub-clinical disease (13), and sub clinical mastitis cause economic damage as result of treatment cost, elevation of somatic cell counts & decrease of milk value, chronic damage to the udder tissue and decrease in milk yield which may cause culling of the infected cows (1,13).
Streptococcus species that cause mastitis include the bacteria Strep.agalctia, Strep.uberis, Strep.dysgalactiae, G group streptococci and other streptococci.
Strep.agalcatiae is the most important udder pathogen and is specific to the udder. Since Strep.agalaciae and Staph aureus incidence in Israel is low, the importance of the other streptococci species as udder pathogen increases.
The other Streptococcus spp. are found on the cow skin (Strep.dysgalaciae & Strep.uberis), lips and tonsils. Those bacteria are secreted in the feces hence contaminate the abdomen skin most often.
Mastitis caused by Streptococci is often clinical mastitis that turns chronic and sub clinical. In Israel, non agalactiae streptococcal mastitis cause a large part of the chronic udder disease. In the years 2001-2004 streptococcus spp. accounted for 12.8-14% of all the isolation taken from clinical and sub clinical mastitis in the national service for udder health and milk quality.
Strep.dysgalactiae was considered as an environmental pathogen and today is thought to be able of infection from udder to udder, as the contagious udder pathogens. The other streptococcus species are from environmental source.
Strep.uberis research showed that during the lactation the spontaneous bacterial and clinical healing rates are low (12).
Sub clinical, non agalactiae, mastitis is treated in Israel traditionally only in the dry period with intra mammary long acting antibiotics. The efficacy of treatment during the lactation has been studied with different results to each bacterium (1, 4, 5, 6, 7, 9, and 10) and with relation to early diagnosis & treatment(7, 8). There are different opinions in Israel in regard to the efficacy of treatment during the lactation. The purpose of this work is to evaluate the efficacy of combined intra mammary and intra muscular penicillin treatment of streptococcal mastitis in Israeli dairy cows, in terms of bacterial healing & decreased somatic cells counts, and to find risk factors effecting the healing. |
|
MATERIALS AND METHODS
Herds & Animals
This study was conducted on the years 2001-4, on naturally accruing field mastitis cases. All cows were Israeli Holstein dairy cows from the KSVM ambulatory clinic farms (n=7). The herd’s average milk yield was 11000 Kg milk (305 days corrected lactation) with average 200000 bulk tank somatic cell counts. Cows infected with streptococcal mastitis were divided into two groups: clinical mastitis and sub clinical mastitis. Clinical mastitis was defined as any change in the milk, the udder and daily milk yield of the cow. The most common clinical manifestation of streptococcal mastitis was the appearance of clots in the milk with a mild decrease in daily milk yield. Sub clinical mastitis cases were defined as cows with high somatic cells count at least in 1 monthly milk record, without a known clinical mastitis episode during the time between milk records. Overall 90 cows (102 infected quarters) were treated.
Treatment & Data Collection
Milk samples were collected from infected quarters, after cleaning the teat end and scrubbing with 70% alcohol. Samples were transported after freezing (-4¢C) to the National Service for Udder Health and Milk Quality Laboratory for bacteriology diagnosis. Treatment was administered 14-21 (average 18.4 days) days after mastitis diagnosis. 45 cows (46 quarters) were re-sampled for diagnosis of spontaneous healing before administration of the first treatment.
The cows were divided to 3 groups according to bacterial diagnosis: Strep. dygalactiae (33 quarters; 18 clinical and 15 sub clinical cases) , Strep. uberis (24 quarters; 6 clinical and 18 sub clinical cases) and other Streptococci (fecal streptococci as Strep. zooepidemicus and Strep. viridans, 45 quarters; 10 clinical and 35 sub clinical cases). The treatment was uniform for all cows, as all 4 quarters were treated once a day using a commercial preparation containing (Nafpenzal® MC Intervet, Holland) 180 mg Sodium Penicillin G, 100 mg Nafcillin and 100 mg streptomycin , and were given IM injection of 20000 IU/Kg BW of Procaine Penicillin (Pen 30®, Vetimex, Holland). Treated cows were milked twice a day, and the same treatment repeated itself for 3 days, once daily. Samples for bacterial healing were taken using the same aseptic technique 21-35 days (average 27.5 days) after the end of the treatment. Somatic cells counts were taken 3 months prior to the treatment and 3 months after treatment from the monthly milk recording system.
Bacteriology and data analysis
Data was analyzed using Microsoft Excel and SPSS ver.10.0. Multivariate logistic regression was used to analyze the effect of the treatment and factors effecting overall healing. One way ANOVA was used to compare the liner score of healed cows to this of none healed cows. |
|
RESULTS
|
Bacteria |
|
Strep. Dygalactiae |
Strep. Uberis |
Other Streptococci |
Quarter No. |
33 |
24 |
45 |
Healed (No) |
31 |
13 |
33 |
Healing rate |
93.9% |
54.2% |
75.5% |
Table 1. Overall quarter healing by bacteria.
Overall healing results are shown in table 1. When factors effecting healing were analyzed using multivariate logistic regression, the effects of Farm, Parity, Season, DIM, Diagnosis to Treatment Interval and the appearance of the case (Sub Clinical Vs. Clinical Mastitis) were not statistically significant and were excluded from the model. Only the causative bacteria and mixed infections effected healing significantly (table 2).
|
|
|
|
|
|
95% CI for OR |
Factor |
B |
SE |
df |
Sig. |
OR |
Lower |
Upper |
Strep. Disgalactiae |
1.806 |
0.812 |
1 |
0.026 |
6.089 |
1.239 |
29.924 |
Strep.Uberis |
-0.943 |
0.563 |
1 |
0.093 |
0.388 |
0.129 |
1.169 |
Other Streptoccoci |
– |
– |
2 |
0.005 |
– |
– |
– |
Mixed Infection |
-2.302 |
1.080 |
1 |
0.033 |
0.100 |
0.120 |
0.8320 |
Constant |
3.047 |
1.087 |
1 |
0.005 |
– |
– |
– |
Table 2. factors effecting overall healing.
The healing was significantly better for Strep. dygalactiae (P=0.026), healing from other Streptococci and Strep. Uberis did not differ significantly, although other Streptococci tended to heal better (P=0.093). Quarters without mixed infection (n=82) healed significantly better then mixed infected quarters (n=20).
Spontaneous vs. treatment healing results are shown in Table 3. When spontaneous healing was compared to healing by the treatment by Multivariate logistic regression, only the treatment effected significantly the healing (P<0.001). No other effecting factor (Farm, Season, Parity, DIM, Bacteria species, the appearance of the case (Sub Clinical Vs. Clinical Mastitis), mixed infection and diagnosis to treatment interval) then the treatment was significant.
|
|
Bacteria |
|
|
Strep. Disgalagtiae |
Strep.Uberis |
Other
Strep. |
All |
S |
No. quarters |
2 |
0 |
7 |
9 |
|
% |
11% |
0% |
35% |
18.4% |
T |
No. quarters |
15 |
6 |
5 |
26 |
|
% |
88% |
60% |
38.5% |
65% |
All |
No. quarters |
17 |
6 |
12 |
35 |
|
% |
89% |
60% |
60% |
71% |
No. quarters |
|
19 |
10 |
20 |
49 |
Table 3. Treatment and spontaneous healing. S – Spontaneous healing, T- treatment healing (% of quarters that did not heal spontaneously).
Healing affected the somatic cell counts significantly. Although the linear score of the cows that healed did not differ significantly in the 3 milking records previous to treatment, the difference was significant in the 3 milking records after treatment. (Fig.1).
|
|
Figure 1. The effect of Healing (■) or Non Healing (□) on Linear Score.
* Statistically segnificant difference between healed and unhealed cows (P<0.001). |
|
DISCUSSION
This work suggests that treatment during the lactation is more efficient then spontaneous healing. The efficacy of the combined treatment of Strp.dysgalactiae mastitis is higher then treatment of Strep.uberis and Other Streptococci mastitis. In a work done on experimentally induced Strep.uberis mastitis the treatment length had a major effect on bacterial healing. A longer treatment period may be needed in order to achieve higher bacterial healing rates when treating Strep.uberis and Other Streptococci (15) or to lower the interval between treatments (16).
Bacterial healing caused a significant decrease in the linear score of the cows, representing the somatic cell counts. The treatment of Streptococci infected cows caused increase of the milk value. |
|
CONCLUSION
The treatment of streptococcal mastitis during the lactation was found to be effective in Israel. Very high bacterial healing rates were found in treating strep.dysgalactiae mastitis. Bacterial healing was accompanied by decreased somatic cell counts. the authors recommend the treatment of :
- Young cows.
- Cows not intended for selection.
- Fresh cows/cows far from the dry period.
- Cows with new intra-mammary infection and with tendency of elevation in somatic cell counts.
|
|
REFERENCE
- Radostits O.M. , Blood D.C. , Gay C.C . Veterinary medicine. 1993. 8TH edition. Bailliere Tindall.
- Rossittto P.V. , Ruis L , Kikuchi Y , Glenn K, Luis K, Watts J.L, Cullor J. S. Antibiotic susceptibility patterns for environmental streptococci isolated from bovine mastitis in central California dairies. J Dairy Sci. 2002. Jan; 85(1) : 132-138.
- Gianneechini R.E., Concha C, Franklin A. Antimicrobial susceptibility of udder pathogens isolated from dairy herds in the west littoral region of Uruguay. Acta Vet Scand. 2002 ; 43(1) : 31-41.
- Cattell M.B., Dinsmore R.P.,Bleschner A.P., Carmen J, Goodell G. Environmental gram-positivemastitis treatment : in vitro sensitivity and bacteriologic cure. J Dairy Sci. 2001. Sep; 84 (9) : 2036-2043.
- Shephard R.W., Malmo J, Pfeiffer D.U. A clinical trial to evaluate the effectiveness of antibiotic treatment of lactating cows with high somatic call counts in their milk. Aus Vet J 200 Nov; 78 (11) : 763-768.
- Wilson D.J., Gonzalez R.N., Case K.L., Garrison L.L, Grohn Y.T. Comparison of seven antibiotic treatment with no treatment for bacteriological efficiency against bovine mastitis. J Dairy Sci 1999 Aug ; 82 (8) : 1664-1670.
- Hillerton J.E., Semmens J.E., Comparison of treatment of mastitis by oxitocin or antibiotics following detection according to changes in milk electrical conductivity prior to visible signs. J Dairy Sci 1999 Jan ; 82 (1) : 93-98.
- Milner P., Page K.L., Hillerton J.E. The effect of early antibiotic treatment following diagnosis of mastitis detected by changes in the electrical conductivity of milk. J Dairy Sci 1997 May ; 80(5) : 859-863.
- Owens W.E., Ray C.H., Watts J.L., Yancy R.J. Comparison of success of antibiotic therapy during lactation and results if antimicrobial susceptibility tests for bovine mastitis. J Dairy Sci 1997 Feb ; 80 (2) : 313-317.
- Guterbock W.M., Van Eenennaam A.L., Anderson R.J., Gardner I.A., Cullor J.S., Holmberg C.A. Efficiency of intramammary antibiotic therapy for treatment of clinical mastitis caused by environmental pathogens. J Dairy Sci 1993 Nov ; 76 (11) :3437-3444.
- Shpigel N.Y., Levin D, Winkler M, Saran A, Ziv G, Bottner A. Efficacy of Cefquinome for treatment of Cows with mastitis Experimentally induced using Escherichia coli. J Dairy Sci. 1997 Feb ; 80(2): 318-323.
- Hillerton J.E.,Kliem K.E., Effective treatment of Streptococcus uberis clinical mastitis to minimize the use of antibiotics. J Dairy Sci 2002 ; 85 (4) : 1009-1014.
- Bradley A.J. Bovine mastitis : an evolving disease. Vet J 2002 ; 164 : 116 – 128
- Radostitis O.M, Herd helth. 2001. 3rd edition. Saunders.
- Oliver S.P, Alemeida R.A, Gillespie B.E., Headrick S.J, Dowien H.H, Johnson D.L, Lamar K.C., Chester S.T, Moseley W.M. Extended Ceftifur Therapy for Treatment of Expiramental Streptoccocus uberis Mastitis in Lactating Dairy Cattle. J Dairy Sci. 2004 ; 87 (10) : 3322-3329.
- Hillerton J.E, Klrsty E.K, Effective Treatment of Streptococcus uberis Clinical Mastitis to Minimize the Use of Antibiotics. J Dairy Sci 2002; 85 (4) : 1009-1014.
|
|
|
|
|