Pig International - November 2017 - 14
14 ❙ PigInternational
Mastitis in sows:
This condition can have serious
consequences for the sow and piglets,
both in the short and long term.
BY ZOE KAY
Inflammation of one or more of the mammary glands
is referred to as mastitis. It is generally caused by
an acute bacterial infection, although it can become
chronic. In the lactating sow, clinical onset is about 12
hours postpartum, having started at farrowing. Mastitis
can affect individual animals or a significant proportion of the herd due to environmental contamination.
Mastitis reduces milk production, leading to poor
intake of colostrum and milk by the piglets. This, in
turn, will cause poor growth rates and potentially a
greater likelihood of disease. Also of economic importance is the reduction in sow longevity.
Causes of mastitis
The most common cause of mastitis in pigs is coliform bacteria, including E. coli and Klebsiella species.
They release an endotoxin that makes the sow unwell and
reduces milk yield. Staphlococcus and Streptococcus
are also fairy common but may be less severe infections.
Bacteria either enter the mammary gland through the teat
opening or via a wound. It can also be a secondary infection following a disease outbreak.
The first signs of mastitis are a high temperature and
refusal to eat. Inappetence, even before farrowing, can
indicate the start of mastitis. Nursery staff may also no-
tice that the sow isn't willing to suckle the piglets. The
mammary glands appear red, swollen and are painful
when palpated. The skin of the affected glands or whole
udder can also be discolored. Bluing of the ears and tail
is also reported, along with a red appearance of the area
around the eye. Observation of a sow's litter may also
give an indication of cases of mastitis. Piglets may initially appear empty and hungry - squealing due to lack
of milk, subsequently becoming quiet and sleepy.
"We see more cases of mastitis in the summer," said
Grace Webster, veterinarian at G W Pig Consultants.
"But it is an all-year-round problem." She described the
two main types of mastitis she sees in practice. "The
first is a sub-clinical infection, where one gland is affected. This is often picked up after weaning and whilst
the sow is not unwell the condition is already chronic."
The second but most important type of cases is acute
mastitis. "Most of the glands may be affected and it will
be obvious that her piglets aren't thriving."
The possibility of mastitis being associated with another other health condition or disease should also be explored.
"Anything that affects the immune system, for example
PRRS, could mean that mastitis is seen as a secondary
www.WATTAgNet.com ❙ November/December 2017