Illthrift is the loss of body condition in the presence of ample feed. Illthrift may be the end result of a wide range of different causes including parasitism (of blood, skin or gut), infectious diseases, specific nutrient deficiencies such as copper, chronic conditions causing organ dysfunction or toxaemia, and conditions causing pain. Contributing causes may be difficult to diagnose such as indigestion, mild ruminal acidosis, depletion of rumen microflora, abomasal ulcer, pneumonia, liver abscess, local peritonitis, and mild laminitis in all four feet. Single or multiple animals may be affected. It is common for some cattle under shipboard conditions to have greater difficulty than pen mates in adapting to the unfamiliar environment, the type of feed and water and the way it is offered. Animals with persistent infection with pestivirus are usually excluded from the export process by testing or visual inspection or both.
Clinical Signs and Diagnosis
During pen inspection, a flank scan may detect affected animals due to a reduction in size of the abdomen (i.e. hollow flanks and a tucked up posture), and wasting of muscles of the back and rump regions. Different hair length, lustre, density and colour may stand out. Cattle may still appear healthy and bright.
The most likely causes of illthrift in shipboard cattle include:
- Shy feeders.
- Chronic toxemia or pain associated with conditions such as pneumonia, pleurisy, rumenitis, liver abscessation and abomasal ulceration.
Necropsy of unresponsive cases may reveal muscle wasting, empty rumen, depleted fat reserves and serous atrophy (jellying) of fat deposits especially mesenteric, renal and bone marrow fat. The pancreas, liver and gall bladder may be atrophied.
The choice of specimens for laboratory differentiation will be dictated by field observations. They may include faeces for parasitology, blood samples to test for trace element deficiencies, and samples from a range of body organs, including fresh sections for bacteriology and virology, and formalin-fixed sections for histology.
Treatment will depend on the diagnosis. Animals with suspected infectious or painful conditions may be treated with antibiotics (procaine penicillin, erythromycin, ceftiofur, or oxytetracycline) and non-steroidal anti-inflammatory drugs (flunixin meglumine, ketoprofen, meloxicam, or tolfenamic acid). Response to initial therapy may be used to guide further treatment. It is possible that long and costly courses of treatment may be required to achieve improvement, and relapse may occur upon withdrawal of treatment.
Preventative measures depend on a good understanding of and anticipation of risk factors likely to affect a consignment.