Research indicates that ewes infected with toxoplasma in early pregnancy experience fetal death and resorption.
Toxoplasmosis in susceptible breeding ewes causes abortions, stillbirths and neonatal deaths. Research indicates that ewes infected with toxoplasma in early pregnancy experience fetal death and resorption.
This is often mistaken for ewe infertility and results in the unnecessary culling of otherwise fertile animals. Ewes infected in mid-pregnancy or later are likely to abort, or give birth to stillborn or weak lambs that fail to thrive.
Toxoplasmosis costs you in three ways:
The loss of lambs by abortion, either by low-level unseen losses, or large-scale abortion storms.
The birth of weak lambs, which fail to thrive or die.
The culling of fertile ewes, which because of undetected early abortion are presumed barren.
Toxoplasmosis occurs throughout New Zealand. Research shows it has been present on 100 per cent of New Zealand sheep farms.
Every sheep flock can be affected by ongoing insidious fetal losses and abortion storms. Ewe hoggets and two tooths are at most risk, but any ewe that contracts toxoplasmosis for the first time while she is pregnant is likely to lose her lamb/s.
There is a vaccine available which is a single dose vaccine that provides breeding ewes with lifetime protection against the effects of toxoplasmosis. Vaccination increases lambing percentage by an average of 3 per cent and decreases the incidence of dry ewes by an average of 14 per cent.
It is a live vaccine, has a short shelf life and is made to order. You need to order vaccine from your vet at least four weeks before you need it, at least eight weeks before mating.
Now is a good time to vaccinate 2 tooth ewes going into your flock as replacements.