Page 536 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

Reproductive system: 2.1 The female reproductive tr act 511

VetBooks.ir Bacterial culture and sensitivity testing are essential within the gland, and aid direct aspiration of any
contents.
to direct the correct systemic and local antibiotic
therapy. Stripping of the gland, hot compresses and
NSAIDs will all improve the well-being of the mare. Management
Chronic cases are difficult to treat and carry a more Drainage of the mammary gland by stripping from
guarded prognosis. the teats will relieve pressure and make the mare
more comfortable. Some clinicians accompany this
Aetiology/pathophysiology with hot fermentations to the gland. Systemic anti-
Mastitis is usually seen in lactating mares or after biotics based on laboratory results may be accompa-
weaning and is therefore most common in the nied by intramammary versions, although the latter
summer and autumn months. A variety of bac- have to be placed in each separate gland and can lead
teria can be involved, but Streptococcus spp., espe- to damage to the teat openings. Antibiotic therapy
cially S. equi zooepidemicus, are commonly isolated can finish 2–3 days after clinical resolution of the
along with a range of gram-negative organisms and infection. NSAIDs are important to decrease the
Staphylococcus spp. inflammation, pain and pyrexia and help the mare
feel and eat better. Abscesses may be drained and
Clinical presentation flushed, often under general anaesthesia. Chronic
The udder is usually hot, painful to palpation and mastitis is difficult to treat due to the extensive fibro-
swollen. There may be secondary ventral oedema, sis and sequestration of infection. Mastectomy may
mammary vein enlargement and hindlimb stiff- be necessary in some advanced and unresponsive
ness. There may be no other signs or systemic reac- cases.
tion, although occasionally mares may show pyrexia
and inappetence. Abnormal secretions are usu- Prognosis
ally retrieved from the gland. Mammary abscesses Many acute cases respond very favourably and
may form in the gland, either as solitary structures quickly with little long-term damage to the gland.
or more widespread, multiple foci. The gland may Chronic mastitis carries a guarded to poor prognosis.
become hard and fibrotic on palpation in chronic
cases. FURTHER READING
Da Silva MdC (2016) (ed) Advances in diagnostic and
Differential diagnosis therapeutic techniques in equine reproduction. Vet
Mammary gland oedema, abscessation, trauma and Clin North Am Equine Pract 32(3):379–570.
neoplasia. Dascanio J, McCue P (2014) Equine Reproductive
Procedures. Wiley-Blackwell, Chichester.
Diagnosis McKinnon AO, Squires EL, Vaala WE, Varner DD (2011)
Clinical signs and the examination of mammary (eds) Equine Reproduction, 2nd edn. Wiley-Blackwell,
secretions are usually diagnostic. The milk may vary Chichester.
from sanguineous and watery to purulent, with large Rossdale PD, Mair TS, Green RE (2002) Equine Veterinary
Education Manual 5: Reproduction – Foaling Part 1:
numbers of neutrophils and possibly bacteria on Maternal Aspects. Equine Veterinary Journal Ltd.,
cytological examination. Bacteriological culture and Newmarket.
sensitivity testing on samples is essential to direct Samper JC, McKinnon AO, Pycock J (2005) Current
therapy. Mammary gland ultrasonography will help Therapy in Equine Reproduction. WB Saunders,
identify the site and morphology of any structure Philadelphia.