Trace element supplementation in cattle at critical times is now common practice, particularly in dairy herds, even when blood or liver levels are within the normal range. The most researched product in this field, is Virbac’s Multimin®.
Trace element supplementation in cattle at critical times is now common practice, particularly in dairy herds, even when blood or liver levels are within the normal range. The most researched product in this field, is Virbac’s Multimin®.
Earlier in this year Virbac released a copper free product with sheep in mind given this species sensitivity when over exposed to copper. Multimin® Copper Free contains selenium, zinc and manganese.
Selenium we all familiar with; this trace element plays an important function in immunity as well as supporting early embryonic life and protects cells through its antioxidant functions.
Manganese promotes healthy development of the egg as well as the healthy expression of heat or oestrus in the ewe and is critical for conception.
Finally Zinc which has many functions within the body but in relation to reproduction zinc’s role is the healthy development of the fertilised egg and development of the embryo.
A published study utilising 3,829 ewes in four Australian merino flocks demonstrated remarkable lifts in conception rates when these animals were injected subcutaneously with Multimin® Copper Free at a rate of 1 mL per 50 kg body weight. The timing of this treatment was 4 weeks pre-tup.
Across the four flocks, scanning lifted by 9% points (126% for treated ewes v’s 117% in the untreated ewes), and twinning increased by 5.8%. Dry ewes decreased from 12.1% to 9.4%.
Similar trials in other published papers support these findings, however as in almost all biological systems, positive results are not guaranteed. There are studies where injectable trace element minerals used pre-tup did not materially lift conception rates. Clearly there are other factors that can and do influence the result: nutrition, breed, and body condition score come to mind.
The other emerging use of Multimin® in sheep is injecting ewes pre-lamb. Again, papers from within NZ and internationally show significant improvements in lamb survival and lamb weaning weights that lead to economic gains when ewes receive trace element supplementation pre-lamb.
If you are keen to explore the use of Copper Free Multimin® in your flock, please talk with one of our vets or commercial managers. This product is available through our clinics.
While there is plenty of talk about the off-label use of regular Multimin® in sheep, (this is the product we use in cattle and deer), please exercise an abundance of caution before doing so in your flock. Regular Multimin® contains copper in addition to the selenium, manganese and zinc. Unless you know the copper status of your sheep do not use this product. Acute copper toxicity in sheep is fatal and devastating.
Figure 1: From MULTIMIN®CF_ResearchSummary: A comparison of scanning rates where half the cohort was treated prior to mating with a MULTIMIN® Copper Free injection
Campy and Toxo
Having our ewes and hoggets pregnant is one thing and ensuring they do not abort during pregnancy or produce weak and non-viable lambs due to infection with either Campy or Toxo is another.
Toxo (Toxoplasmosis) is found on all sheep farms and it is a disease spread through cat faeces with ewes/hoggets eating contaminated pasture or hay.
Control is achieved through vaccination of hoggets or two-tooths 4 weeks prior to their first mating. One intra-muscular vaccination provides lifetime immunity.
Campy, is a different kettle of fish; with this disease carrier sheep shed infection through uterine discharge and it is these sheep and ewes which abort provide the on-going source of infection for flocks. 88% of all flocks have infected ewes within them and typically within infected flocks, 50% of the animals show no immunity to Campy.
Vaccination is again the way to prevent Campy abortions and lower lamb losses between lambing and weaning due to lambs weakened by infection but not aborting, prior to birth.
Unlike Toxo, Campy vaccinations require an initial and booster vaccination prior to first mating. Thereafter an annual vaccination is required if the flock is to be protected.
Figure 2: From MSD Animal Health: Campyvax®4 Vaccination Programme
While it is common practice to vaccinate hoggets or two-tooths for Campy prior to their first mating, many do not repeat this vaccine on an annual basis and the immune status of the flock decreases.
In known infected flocks, when annual repeat vaccinations are undertaken, significant increases in tailing percentages are seen.
An Otago farmer saw a 10% reduction in lambing percentage in his mixed-age ewe flock after discontinuing his annual Campyvax4® booster vaccination. This occurred for two consecutive years before he reinstated the annual Campyvax4® booster programme and his lambing percentage returned to where it was before he had ceased boosting his MA ewe flock. He stopped seeing slipped lambs prior to lambing, and overall, the lambs seemed bigger and healthier. More information on this case is available HERE.
If annual vaccination of the flock is a step too far, our advice is revaccinating year after your hoggets or two-tooths received their initial and booster shots.
Like the clostridial vaccines, Campyvax4® is a dead vaccine and unless boosted, the individual ewe’s immunity will drop away.
Our vet team and commercial managers are happy to discuss and to confirm your vaccine orders for the coming season.