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2.11.1 Ephemeral fever
This is an insect transmitted viral disease also known as three day sickness affecting the musculoskeletal system of cattle mainly in the northern Australian wet season. There is the
possibility that animals incubating the disease may be loaded on board. The first sign is usually multiple animals, up to 80 of a group showing shifting lameness or difficulty rising.
Other signs include prolonged recumbency, fever, inappetance, lachrymation, salivation. Severest cases are large framed and heavily muscled. Complications associated with
prolonged recumbency cause deaths in a small percentage of animals. Treat recumbent animals for hypocalcaemia and with anti-inflammatory drugs, and nurse -
don’t stress or work. Oral rehydration should be avoided if swallowing is compromised. Mildly affected
animals recover in several days without intervention. A vaccine is available to assist prevention.
2.12 Straining
The likely causes of straining in shipboard cattle include: prolapse of vagina or rectum from advanced pregnancy, over-fatness or persistent
coughing rectal mucosal irritation from chronic diarrhoea
urethral obstruction Intrapelvic pressure associated with advanced pregnancy, over-fatness, persistent coughing
or prolonged recumbency may induce partial prolapse which leads to mucosal injury, straining and complete prolapse of the rectum, vagina or both. Post-partum injuries, urinary
tract obstruction in males and rectal mucosal irritation from chronic diarrhoea may also cause straining and prolapse of rectum and vagina.
Attempt to replace and fixate, or amputate prolapses if facilities and equipment are available. Prolapse of the vagina is usually most appropriately reduced and retained by insertion of a
perivulvar Buhner ’s suture. Prolapse of the rectum, unless very small, is best amputated.
Amputation can be performed after placing a series of U-sutures around the base of the prolapse. A 23cm Gerlach needle carrying two 30cm lengths of heavy duty absorbable
suture sutures 1 and 2 is inserted into the lumen of the prolapse and the prolapsed tissue penetrated from the inside to the outside. The Gerlach needle is then used to carry the inner
end of suture 2 and a new suture 3 from the lumen to the outside about 3 cm from the first penetration. The Gerlach needle is then used to carry the inner end of suture 3 and a new
suture 4 from the lumen to the outside about 3 cm from the second penetration. Suturing continues in this manner for the circumference of the prolapse until there is a series or U
sutures around the prolapse. Each suture is tightened and tied, then the prolapse excised about 2 cm distal to the sutures. No haemorrhage occurs due to the ligation of the tissues.
Spontaneous retraction of the stump occurs.
Simultaneously treat any underlying cause such as pneumonia, urolithiasis or diarrhoea. Prompt euthanasia is recommended if the prolapse cannot be corrected.
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3 Investigation of sick cattle
3.1 Be aware of diseases and conditions causing sickness
Kategori