Every docking season, an on-farm management decision is made around whether ram lambs are left entire, to castrate (wether) or push the testes back into the body cavity (crypto). Lots of research has been done on this topic, yet there is still plenty of debate as to what is best on farm.
Some farmers base their decision on management factors i.e. less chance of ewe hoggets being mated, reduced ram behaviour, less chance of spreading Brucella ovis or less crutching. However, some farmers base their decisions on economics, with the overall perception that ram lambs will be the fastest growing.
A research trial was undertaken by Massey University to answer this question. It found:
there was no difference between entire rams and crpytos for any of the growth, carcass and value traits considered. Hence using cryptos will not compromise the profitability of lamb finishing systems
wethers are less profitable (slower growth rates and more overfats) and therefore should only be used where management issues outweigh the financial impact.
Are Tapeworm drenches worth it?
A national drench survey in 2006 showed 90% of farmers give a tape drench pre-weaning. But is it worth giving a lamb a tapeworm drench?
A Manawatu FITT research project was undertaken in 2010-11 to answer this exact question. In this trial there were three groups:
Control (no treatment)
Worm (Triple Combination Drench)
Worm + Tape (Triple Combination Drench + Praziquantel (to control tapeworm))
The results showed:
A liveweight gain to a tapeworm drench (as is the case in this trial) goes against almost all of the research done previously. Drenching for tape generally results in a yard full of tapeworm and this fills a farmers’ heart with joy to see the positive effect his drench has had.
A reduction in dag score leads to less dagging and a reduced flystrike risk.
The true response to a tapeworm drench will vary from farm to farm and how well the ewes have been looked after.