Here's Why It's Important to Control Mastitis During the Dry Period
Dry cow mastitis therapy is necessary to treat existing infections and to
prevent new infections in the early dry period. The figure below illustrates that
new mastitis infections peak at dry-off and in early-lactation.
These research studies document mastitis cases during the dry period:
- 60% of all gram-negative intramammary mastitis infections occur during the
dry period (Todhunter et al., Am. J. Vet. Res. 52:184, 1991)
- In a UK study, more than 50% of all clinical mastitis due to
Enterobacteriacae arose from quarters that had previously become infected
during the dry period (Bradley et al., Proceedings of the National
Mastitis Council, 1999)
- Untreated intramammary infections can remain
quiescent in the udder until calving, causing mastitis in early lactation
(McDonald et al., Am. J. Vet. Res. 42:229, 1981)
Clinical mastitis is most common in the first 100 days after calving. Severe
cases cause decreased milk yield, poor reproduction, loss of quarters and/or
death of the animal. Other possible effects of severe mastitis are endotoxemia
and fever, which may reduce the cow's appetite and lead to negative energy
balance.
A University of Tennessee study conducted by Schrick et al. confirmed that
cows with subclinical mastitis suffered reproductive problems. The worst effects
occurred in cows that were subclinically infected and then became clinical
between first service and pregnancy. Clinically infected cows had 93.9 days to
first service compared to 67.8 days for cows without mastitis; 196.0 days open
vs. 85.4 days; and 4.3 services per conception vs. 1.6 services.
Mastitis prevention actions
- Provide clean and dry housing. Clean, dry and comfortable housing is a must for both dry
and lactating cows. Use the knee test to check bedding moisture daily. Stand at
the back of a freestall or on a bedding pack and drop to your knees. Upon
standing again, if your knees are damp or wet, the bedding should be
changed.
- Use proper dry-cow mastitis treatment and vaccinate with UPJOHN J-5 BACTERIN™
(Escherichia Coli Bacterin J-5 Strain) to minimize mastitis during the dry and
transition periods. Data compiled for three lactations demonstrate consistent
performance advantages over non-vaccinated herdmates.
Table 1 summarizes a multi-location trial starting with more than 400 cows. Vaccinated vs. control cows were evaluated over three lactations. The vaccinated cows averaged a 65 percent reduction in clinical coliform mastitis cases over the three years.
Table 1
 |
Results of UC-Davis J-5 Trial #1 |
|
| |
Vaccinated
Group*
|
Non-Vaccinated
Controls
|
|
| Number of animals |
246
|
240
|
% incidence of clinical
coliform mastitis |
2.57
|
12.77
|
# culled due to clinical
coliform mastitis |
0
|
4**
|
*Three doses of J-5 were delivered to 246
adult cattle.
**Three animals were culled due to chronic coliform mastitis,
and one because of post-coliform agalactia. |
|
|
|
(Gonzales, R.N., J.S. Cullor, D.E. Jaster, T.G. Farver, R.B. Bushnell and M.N. Oliver,
"Prevention of Clinical Coliform Mastitis in Dairy Cows by a Mutant Escherichia coli Vaccine,"
Canadian Journal of Veterinary Research, 1989;53:301-305)
UPJOHN J-5 BACTERIN Delivers Results
In a trial involving 486 cows, the vaccinated group showed an incidence of coliform mastitis of just 2.57 percent, compared to a 12.77 percent incidence for the non-vaccinated control group.
Table 2
|
Results of Tulare VMTRC J-5 Trial — Coliform Mastitis Incidence |
|
| |
Upjohn J-5
|
Placebo
|
% reduction by Upjohn J-5 |
|
|
(Borrell, C.L. et al, Abstract 12, 11th Annual Food Animal Discovery Research Conference, UNR, 1990)
Reducing the number of cows culled due to coliform mastitis is often
overlooked when considering the numerous advantages of using
UPJOHN J-5 BACTERIN.