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McHugh Components Ltd. 89 Broomhill Road, Tallaght Ind. Est. Dublin 24
Ph: (01) 4137000 · Fax (01) 4145370 · Website: www.mchc.ie · Email: info@mchc.ie
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C O M P O N E N T S
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h y d r a u l i c c o m p o n e n t s
· Online Ordering
· Next Day Delivery
· Customer Friendly Sta
· Log on @ www.mchc.ie
· Follow us on
All these brands under one roof:
McHugh Components Ltd. 89 Broomhill Road, Tallaght Ind. Est. Dublin 24
Ph: (01) 4137000 · Fax (01) 4145370 · Website: www.mchc.ie · Email: info@mchc.ie
The Parts Specialists
C O M P O N E N T S
C O M P O N E N T S
www.mchc.ie
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h y d r a u l i c c o m p o n e n t s
McHugh 200x283.indd 1
26/04/2018 11:07
Streptococcus uberis is recognised in many
countries around the world as the problem
mastitis bug that can cause di cult-to-cure
cases that often recur, writes Andrew M Biggs
This is epitomised by the common phone call conversation
farmers have with their veterinary surgeons saying, "I
treated the cow and all seemed to be going well until just
before I was going to return her milk to the bulk tank,
when the mastitis came back again." Hardly surprising,
then, that it gets called the frustrating mastitis bug.
Successful treatment is often elusive in these situations
and so preventing S uberis mastitis cases is much more
rewarding than attempting to treat your way out of a
problem.
What is S uberis and where can you find it?
S uberis is a bacterium which commonly causes both
clinical and subclinical mastitis in dairy cattle. It has the
ability to colonise both animals and the environment and
is predominantly found in manure and organic matter
including bedding materials. S uberis has been found in the
alimentary tract (lips, tonsils, rumen, rectum and faeces),
respiratory tract, urogenital tract, infected wounds and
abscesses and coat of cattle as well as the teat orifice, teat
canal, teat skin and infected mammary glands of cattle.
How does S uberis spread?
S uberis spread is mainly via the alimentary tract from
cows licking and grooming, with around 50 per cent of
dairy cow skin samples being positive for S uberis to faecal
contamination of the cow environs, and around 25 per cent
of cow faeces being positive for S uberis and grazed pasture
having higher levels of S uberis than ungrazed pasture.
Faecal contamination of bedding in loose yards or cubicle
(free stall) beds in housed cattle will also result in high
levels of S uberis, with particularly organic cow bedding
such as straw or sawdust facilitating further multiplication.
The presence of S uberis in the environment results in
contamination of teats and teat ends and subsequent
intramammary infection with high bacterial counts
resulting in increased infection rates.
When do intramammary infections
with S uberis infection occur?
Dairy cows are most commonly infected from
environmental sources in the dry period, often resulting
in clinical cases in the subsequent lactation although
infection can also originate in lactating cows, with the
first 75 days of lactation being a greater risk period than
the rest of the lactation. Up to 60 per cent of clinical
cases of mastitis can have their origins in the dry period
with highest infection rates seen just after drying off and
around parturition. Strain typing has shown that some
S uberis infections can become persistent and then have
the potential to behave in a contagious manner. In this
situation, often there are only a few different strains found
on a single farm as opposed to the multiple heterogeneous
strains found in herds where environmental sources are
important.
How common is S uberis mastitis?
S uberis mastitis is found throughout the world and is most
common in countries with a developed dairy industry. It is
designated as an environment-associated major pathogen
and often accounts for approximately one third of clinical
cases (see Figure 1).
How long do S uberis intramammary infections last?
The duration of S uberis infections can vary considerably,
with around 60 per cent of infections lasting less than
30 days; however, it is thought approximately 18 per cent
can become chronic and last >100 days. There are reports
of Streptococcus infections persisting through dry periods
and lasting up to 20 months. Although these subclinical
Figure : Vale Laboratory UK
clinical mastitis isolates
.

Staph aureus %
Coag -ve Staph %
Yeast %
Coryne bovis %
Contaminated %
Trueperella pyogenes < %
Strep uberis %
Strep dysgalactiae %
Enterococcus faecalis < %
Bacillus spp %
E coli %
Klebsiela spp %
Other Gram ­ve %
No growth %
MAY 2018
www.irishfarmersmonthly.com
Herd Health
Streptococcus uberis: the
frustrating mastitis bacterium
IFM_May_2018.indd 63
02/05/2018 07:38