Common Disorders affecting sheep - Lactation disorders

Mastitis

  • mastitis can develop rapidly
  • may be an obvious cause (damage to udder, bruising, wire cuts, sore mouth scabs)
  • various levels of severity (some cases are sub-clinical, but will still cause injury to the udder and decrease milk production)
  • in the obvious cases, the udder becomes hot and painful (may cause fever)
  • ewe carries one leg away from udder
  • lamb may look hollow if milk decreased
  • mastitis is a common sign of the Maedi-Visna virus, both sides of the udder are hard but not hot

Cause

  • bacteria such as Staphylococcus spp. or Pasteurella spp causes infection of the udder
  • maybe related to injury or unsanitary conditions

Treatment

  • depends of severity of infection
  • frequent stripping of milk out of udder (at least twice per day)
  • intravenous or intramuscular antibiotics injections may be useful

Prevention

  • unless lumps and abscesses are very small, the affected and recovered ewe should be culled from breeding flock.
  • keep ewe housing areas clean and well bedded
  • if you suspect Maedi-Visna, see Respiratory Disorders for details

Sheep with mastitis

Blue Bag Masitis

  • very severe form of mastitis
  • udder is very swollen, hard, and has a greenish colouration
  • infection generally spreads through the body (systemic poisoning)
  • the ewe becomes feverish, quite ill and may die in a day or two
  • if ewe recovers, the affected half of the entire udder no longer produces milk

Cause

  • as above, likely to have an udder injury

Treatment

  • call your vet
  • hot packs applied to udder using hot water and liniments
  • intravenous or intramuscular antibiotic injections may be useful
  • early treatment is essential

Prevention

  • as above

Agalactia
(Lack of milk)

  • ewe produce little or no milk.
  • may be little udder development as the ewe nears lambing
  • no fever, illness, pain, or oedema of udder
  • there may be a hard fibrotic lump within the parenchyma of the udder with an extension from this fibrous mass descending down into the teat canal, causing an interruption of milk flow
  • milk (if there is any) appears normal in colour and consistency, simply not enough of it
  • occurs among first time lambing ewe lambs as well as older ewes.
  • maternal behaviour may be normal, or ewes may be less willing to allow lambs to nurse (especially with young ewes)

Cause

  • cause not known
  • possible influencing factors:
  • chilling of udders
  • excessive barley feeding
  • mastitis infection not cured
  • mycoplasma infection
  • early lambing (Dec-Jan).

Treatment

  • none (some ewes are slow to start milking after lambing, and milk production may pick up after a few days)

Prevention

  • cull affected ewes.