Common throughout New Zealand and most commonly seen in lambs where muscle activity is effected causing ‘White Muscle Disease’ This is seen as inability to walk to sudden death due to effects on the heart muscle. In older sheep the same conditions can be seen but more often it is poor growth rates and reproductive performance.
Most properties provide selenium through fertilizer applications or through oral or injectable supplements. Often selenium is combined with other monerals in a mineral drench or combined with a parasite drench. Injectable selenium is available on its own or incombination with Vitamin B12 which last around 6 weeks in the animals system. Longer acting injections are available (Deposel) that last about 12 months. Oral supplements are very short acting.
Selenium is toxic, so care in dosing is important. Never give two products containing selenium at the same time (i.e a drench and a vaccine for example).
Deficiency is primarily a wasting disease due to anorexia, ill-thrift and anaemia with occassional death. Young sheep are most effected. Cattle and deer can also be effected.
Historically, Bush Sickness was the disease caused by then, an unknown cobalt deficiency. Today, fertilizer applications have virtually eliminated the disease, except in young stock especially lambs. Growing sheep, require cobalt or more particularly, the Vitamin B12 which is produced with cobalt being available to the animal. The main sign recognised in New Zealand is in weaned lambs is an impaired growth rate which usually respondes quickly to injections of Vitamin B12.
Cobalt is available in oral drenches and mineral drenches in combination with other minerals. Vitamin B12 is available in injectable forms that last in the animals system for up to 6 weeks. Some vaccines (Clostridial) also have Vit B12 in them.
The treatment and prevention options are varied and need to fit with other farm activities.
Although New Zealand soils are generally copper deficient, sheep are less susceptable to low copper levels compared to cattle and deer. Because of this, copper deficiency is rare in sheep in most New Zealand areas.
However, copper poisoning is seen and has been associated with the use of copper sprays in nearby tree plantations. This is usually seen as a sudden death.
If you believe that you may be deficient in copper, we suggest that you contact us. Levels can be assessed easily with blood of liver samples. With cattle or deer copper deficiency is much more common.