Abstract:
Much research has gone into developing a sustainable
management tool for haemonchosis, namely the
FAMACHA© system, which has been validated by numerous
studies worldwide. However, the financial implications on
production of implementing this system have not been fully
investigated in sheep previously. A trial was conducted on
a farm comprising a flock of approximately 300 Mutton
Merinos on which the FAMACHA© system was in use.
Seventy five maiden and multiparous ewes were randomly allocated to the following three trial groups: (i) FAMACHA©
in which ewes judged to be incategories 4 or 5 were dosed
with levamisole HCl 2,5% (Nemasol NF, Intervet); (ii)
Conventionally dosed in which all ewes were dosed every
six weeks with levamisole HCl 2,5% (Nemasol NF, Intervet);
(iii) Suppressively dosed in which all ewes were injected
every six weeks with moxydectin 1% m/v (Cydectin, Bayer
AH).
There were no significant differences in body weight
gains, FAMACHA© and body condition scores amongst the
three treatment regimens for ewes that did not conceive.
For those that became pregnant during the trial there was a
significant difference when analysed by calendar date but
not when analysed by reproductive stage. There were also
no significant differences between trial groups in lamb birth
weight and, after slow growers had been sold, the average
daily gain of the lambs born to ewes in the trial. The cost of
anthelmintics was considerably lower for the FAMACHA©
group. In conclusion there were no significant differences in
selected production parameters when using the FAMACHA©
system as opposed to other methods of anthelmintic use in
a Mutton Merino flock in a semi-intensive farming system and that the gestation status should be taken into account
when measuring these parameters in future studies.