A very effective way to boost lamb numbers
Media release from Intervet
A very
effective way to boost lamb
numbers
Many New Zealand sheep farmers
will be looking at ways of improving their flock’s
productive efficiency over the coming season to maximise
lamb numbers.
It’s therefore timely that the reformulated sheep fecundity vaccine Androvax®-plus has just been released into New Zealand’s animal health market. Intervet New Zealand now produces the vaccine as a premixed, one-container product rather than a product that requires mixing before use.
It would be fair to say the fecundity vaccination is one of those influential developments that has swayed the course of farming in New Zealand. Androvax® has had a substantial impact on increasing lamb numbers, with 17 million doses of its original formula sold since its release 13 years ago, meaning millions of additional lambs.
The vaccine, which produces an average increase in lambing of 20 percent , has become a routine part of farm practice. It is an increasingly valuable tool to manage sheep fertility in different and sometimes difficult farming environments, with farmers using the treatment to “switch” increased fecundity (reproductive ability) on and off.
Intervet veterinarian Dr Andrew Dowling explains that because the effects only last one season, the fertility treatment has been giving farmers welcome flexibility in increasing lamb numbers when and how much it suits them.
“Farmers can choose what years they treat, get the results, and choose not to use in other years. It’s a choice that can be weighed up each season, depending on their production requirements, and in response to specific seasonal issues,” Dr Dowling said.
And of course producing more lambs is a very positive option for farmers to boost income when returns are lower.
Farmers are not necessarily treating their whole flock, but often vaccinating “historical” singles, or using it on their two-tooth’s who often lag well behind the mixed-age ewes in fecundity.
“Vets are telling us there are two very compelling reasons behind New Zealand farmers using the product; more lambs without genetics, and in response to adversity,” Dr Dowling said.
Flexibility is a particularly useful alternative for farmers wanting to increase lamb numbers without genetics. The vaccination allows farmers to manage fecundity without necessarily resorting to genetic selection to improve a fertility trait. It’s instant, so farmers can reap the benefits of producing extra lambs without the two-to-three year time lag that genetic selection requires to get results.
Having the ability to influence fecundity is invaluable for farmers managing difficult climatic events, and is often an integral part of drought strategy. Farmers recovering from a prolonged dry period, for instance, having been forced to destock, can increase lamb numbers quickly and in a planned and consistent way. That gives them the ability to rebuild breeding flocks and also to manage good spring and summer growth as pasture recovers.
“The vaccine has been very successful already; we’re just elevating it to that next stage of development, taking farmers needs into account and making it easier to administer. From a practical point of view, using Androvax®-plus now will simply mean less work in the yards for farmers, particularly as it’s also now available in larger size packs. It will benefit farmers whose management and feed strategies are in place to lamb and rear at least 20 percent more lambs.”
Androvax® works by triggering antibody levels to change hormone production, allowing the production of more eggs in the vaccinated ewe. It is however a vaccine, rather than an active steroid or hormone, therefore there is no residues in meat of treated ewes or their lambs. The increase in ovulation rate is temporary, lasting one season.
ENDS