Since my latest update, we took two types of pasture samples, blood samples from the sick wethers, autopsied two of them with full organ, tissue and blood sampling, and have done a range of faecal egg counts and some very interesting trials on drenching.
At the time of writing, we are still waiting on many of the organ and plating out for disease test results, but enough results have come in to confirm what the severe scouring problem was. Thank you too to everyone who emailed and called with their experiences. We have and are implementing nearly all of those suggestions and trialling some others. I appreciate the sharing of experiences.
The scouring was not from worms. It was not from disease, though small amounts of disease causing organisms have been found in the tests. It was not from nutrient deficiencies like copper being too low etc. All the nutrient levels have come back fairly good. Blood tests show copper was OK but we are waiting on organ tests for a more accurate result. We do know molybdenum is still too high but it looks like we have that balancing out quite well now with the higher amounts of copper we have been supplying.
We did two pasture tests. One to CSBP for nutrients, and one to Agrifood to test the pastures for hay quality parameters. It won't look like it from the photo's, but we are quite low in protein. We weren't a few months earlier when the problems were happening, but because I have not kept the nitrogen levels up, the spring pastures are now low in protein. And that has been a good thing. The sheep have improved so much with the lower protein diet.
The bottom line so far is that until we can do better genetic selection on a bigger scale, no matter how good the pastures are, supplying straw and hay is not enough. We need to supply some starch to the lambs before they are weaned, and we will experiment with that a few weeks after weaning. This is of course not because the sheep need the energy as there is plenty in the pastures, and they do have the straw and hay for roughage to utilise the pastures better.
However, the little bit of starch will stimulate the rumen to develop properly. The autopsy's confirmed the rumen development was poor. The high protein diet and lack of starch has stopped the rumen growing fully. Adding starch, even just a small amount, will stimulate the rumen to be much bigger and enable the protein to be utilised so much better.
Only the ram lambs and wethers had access to lupins. They are the only ones who suffered severely from the scouring. Lupins + lush pasture = backfired. The ewe lambs weaned the same day have hardly scoured, have put on lots of weight and are currently in with the rams. They went in at 6-7 months old and out of all the ewe lambs born in March/April (>600), only about three should be culled. The lupins given to the ram lambs and wethers was in an attempt to use up the left over lupins and make the sheep grow faster, but it backfired. It's been a really good learning event and has shown another side of the genetic diversity we have in front of us to select from.
I could go on, but I want to mention some of the other trial results we did. Backlining moxidectin drench so far has worked as well as the injection. We have been using that technique for over a year and it seemed to work, and we now did a trial numbering the ewes and taking pre-trial poo samples (up to 1,000 egg counts), and two weeks later to check individual animals. Both treatments tested all zero's. As a sub-note though, moxidectin does not last long on this property. We need other modes of action to control the worms for longer.
But to me the most interesting result is what we did on the hay. We have two mobs of ewes lambing. Within each mob, we had the ewes who lambed for the first time (5-week joining) and the ewes who were lambing for the second time this year (also a five week joining). And between each mob lambing was a 10-day gap. We have been monitoring the poo egg counts and they had risen to 200's in one paddock and 300's in the other. And since there were still weeks of lambing left and then another 2-weeks before marking the lambs and therefore having the ewes in the yards to be able to drench them, the ewes were in danger of worm numbers exploding.
So after some guesstimates, we mixed ivermectin with molasses and a few nutrients onto the hay as a look-see trial. Two weeks later, the egg counts came back as all zeros. This was completely unexpected because we know moxidectin does not last long and ivermectin being weaker (same mode of action) probably would not work. It did. Yay. So that has given us a lovely hiatus until the ewes come into the yards at lamb marking time when they will be given a proper range of drenches. Ivermectin is very cheap. Thousands of dollars cheaper per mob than other drenches.
One other important note on the worm egg counts. We consistently now have 4-6 out of 10 poo samples testing zero's even when others are very high. As we keep building our ewe numbers from the rams that have some worm resistance, we appear to be having success in more ewes also having very handy levels of worm resistance. This is very encouraging to me.
Now to some photos.
And a final photo showing the rainfall so far over the past twelve months. After our usual dry summer, we have had a very good season. Since the end of February, we have not gone more than 8-days without rain, and there has not been too much of it either. June was unusually warm and sunny and pastures grew like spring time. July and August were very cold and we have remained cool all the time until the time of writing (14th Nov 2022). October has been our wettest month of the year and we have just received 37mm of rain over three days (11th-13th November).
We have also been spraying out the bromegrass and barleygrass with a range of FOP herbicides - more than a week apart with a contractor. It's too early to see how successful that has been over the whole farm, but hopefully it will drop the seed production down of the brome and barleygrass. The early observations with propaquizafop has been an excellent result. We sprayed later with quizalofop, and now patching out small areas with propaquizafop. Our ryegrass is FOP resistant so is mostly unaffected. We've done a trial over 1ha plus the raceways with 4x the rate of quizalofop to see just how FOP resistant it is. Next year when we hopefully have our own boom, we will be spraying the same herbicide in May-July. Exactly when we will spray depends on how the grasses are growing.