Hunterville Vet Club

18/06/2025

Fertiliser Toxicity

It is good to see planes flying and trucks working again as farm budgets allow fertiliser to be put back on the agenda.

Just a reminder to consider the possible risk that fertiliser application poses to stock grazing pastures when super phosphate fertiliser has been applied. In the small print you will find that Ravensdown and Balance state that stock should not graze dressed pastures until 21 days after application or after significant rainfall—25mls. In practice this does not always happen!!

Over the years we have had cases of toxicity. When problems have occurred it has generally been when fine, dusty superphosphate has been applied at high rates (200kg / ha +), grass covers have been over 1400kgs / ha and the grass has been damp either from a good dew / frost at the time of application. In this situation the fert has stuck to the leaf rather than falling through the sward to the dirt allowing ewes in particular to ingest damaging amounts of fertiliser.

The answer is not to apply high rates of fert or good covers if the grass is damp and stock are likely to graze the area before good rainfall occurs. Often this just means waiting until the afternoon for things to dry out.

A point to note is that it is not the superphosphate as such that causes the poisoning. Fluorine is a contaminant found in phosphate rock which causes kidney damage if ingested and is the cause of the toxicity.

16/06/2025

Watch Withholds

A reminder to dairy farmers to keep drug withholds in mind at this time of the year. Two of the ones that can catch you out are:

*Drench milk withholds. Some Abamectin drenches used to have a nil milk withhold. This is no longer the case! If you want to drench cows or incoming heifers in the dry period or in lactation, Eprinomectin based drenches such as Eprimax or Eprisure are the only type now available with a nil milk and meat withhold.
*Dry Cow treatment withholds. If you have used Cepravin, the milk withholding period is 49 days. If the cow calves early or slips, milk cannot enter the vat until the 49 day withhold and first 8 milkings has elapsed. The same advice applies to shorter action dry cow treatments, but withholds are also shorter so it tends to be Cepravin that causes any problems.

11/06/2025

Autumn Issues

We are now into June and heading towards the shortest day. At this time of the year there are a number of animal health issues that need to be kept in mind and action taken where required.

Nitrate levels in new grass and crops.
It pays to test these types of feed before introducing stock to them, especially cattle. Testing over the last month has revealed a wide range of results from very high and dangerous, to low and safe.

Sudden ewe deaths.
Whenever you note dead ewes for no good reason you should consider the one good reason that often occurs at this time of the year—Salmonella. We reported on an outbreak in last months newsletter and have had two further outbreaks.
We have also reported on two salmonella outbreaks in dairy cows. Dairy farmers should be concerned when cows develop sudden diarrhoea and are obviously sick, especially where herds have not been vaccinated.

Autumn worm burdens.
We have had several cases of poor weight gains and lamb deaths as a result of high worm challenges or poor worm kills due to drench resistance issues. On many properties the next worm drench will be the last one for ewe hoggets. It is really important that this drench is highly effective. You do not want to leave resistant worms behind that happily go on producing eggs over winter to infect next seasons lambs. For most that means closing out with Zolvix or Startect drench.

11/06/2025

This wee cutie is looking for a new home.
Phone Gaye on 027 3277084 for more information.

09/06/2025

2025 June Newsletter

29/05/2025

House wanted to rent by a staff member of HVC.
Preferably between Hunterville and Feilding but anything considered.
Ideally looking to graze a couple of horses as well.
Phone or message Sam on 0274185008

20/05/2025

15/05/2025

Beef Pregnancy Testing

Generally results for beef cow pregnancy testing have been relatively good this year, many herds coming in at 5% to 8% empty rates. However some herds have been significantly worse with up to 25% empty cows. Investigations reveal the same two major culprits when cow condition and feeding are not an issue—BVD and bull problems.

Both these problems can be solved or minimalised with good management practices. Blood testing and vaccination programmes for BVD will address the BVD issue. When it comes to bulls, bull testing and semen evaluation can be considered. However, good bull management meaning keeping a close eye on bulls over mating, and having sufficient numbers of bulls, are also very important components in minimising problems.

13/05/2025

Sudden Death in Ewes

In the last month we had a case of sudden ewe deaths in well conditioned, healthy ewes. Around 10 ewes had died over a couple of weeks. At this time of the year, and given the ewes were generally in good order, a Salmonella outbreak was by far the most likely cause of death.

A post mortem examination of a dead ewe demonstrated all the signs we associate with Salmonella deaths in ewes—a good conditioned ewe with a greeny blood tinged scour around the tail. The intestines were inflamed and reddened with blood tinged content.

This ewe flock had no vaccination programme in place. Immediate vaccination was recommended for all the ewes on the property. At this point deaths had only been in one mob but from dealing with many outbreaks over the years it is only a matter of time before the infection jumps into other mobs of ewes. Within 10 days the deaths had ceased.

A large number of our clients have vaccination programmes in place when it comes to Salmonella. We would advise clients who don’t, to consider talking to us about vaccination especially given the way ewe values are heading! There are programmes that deliver good levels of protection for minimal cost and while not being totally in line with the manufacturers recommendations, have proven very effective for our clients over many years.

10/05/2025

Copper Injection v Capsules in Bigger Cattle

Being out on farm pregnancy testing I often get asked about the merits of copper capsules versus injection in cattle. As we have recommended in previous newsletters, while we certainly prefer the option of copper capsules in younger cattle, the use of copper injections in cows and older steers has it’s place. The appropriate sized copper capsule will supply adequate amounts of copper for significantly longer periods than a single copper injection. However following up with a second copper injection 3 months after the first should give very good supplementation. This generally means giving a second copper treatment pre calving for cows. Where handling facilities / head bales are not great this can be a lot easier than trying to get capsules into big cattle.

09/05/2025

Facial Eczema Cases

Over this eczema season spikes in spore counts were observed at our monitor sites and in cuttings supplied by clients. While big outbreaks of FE have not occurred, in recent weeks we have had plenty of reports of sheep with clinical signs of eczema breaking out. This would indicate that subclinical eczema damage is likely to have occurred in sheep and cattle on many properties. This will have resulted in decreased weight gains in your sheep and cattle. It is also likely that come scanning time there will be ewe flocks out there that have been negatively impacted by FE. Resulting in more dry ewes and scanning percentages that are a little less than anticipated.

What is also evident is that each year FE now seems to be a threat. We have been fortunate that once again, while spore counts rose, we did not get that final warm period to drive spore counts into really dangerous levels. What we do know is that eczema tolerant genetics would be a wise move for many of our clients.

08/05/2025

Here is the link to our May 2025 Newsletter.

Please give us a call if you have any questions.