I always enjoy on-farm trials, because they require a whole farm system approach – something we do not see a lot of these days. Supporting farmers who are curious and motivated enough to invest their own time to clarify a management technique’s impact or settle an old wives’ tale is a highlight of my job.
Taumarunui vet Ginny Dodunski and Landcorp’s Meringa Station recently completed a “FITT” (“farmer-initiated technology and transfer”) trial into metabolic treatments for triplet-bearing ewes and their impact on ewe and lamb survival, as well as lamb weight.
How the trial came about
Recent science suggested farmers in the lower North Island stood to gain $23 million annually if they could lift triplet lambing from 180 per cent to 250 per cent. Triplet-bearing ewes tend to have a higher death rate and be more metabolically unstable than single or twin-bearing ewes.
The trial involved 262 mixed-age ewes – all scanned with triplets. The ewes were drafted into age groups and randomly allocated into treatment or control groups.
Each ewe age group contained a similar number of treated and control animals. Younger ewes (two and three-year olds) were lambed together in small easy paddocks, while the older ewes were lambed in a single mob on rolling-to-medium hill country.
Treated ewes received a regime of products, designed to minimise metabolic disorders. Namely: an injection of vitamin A, D and E; a magnesium pidolate drench; and a long-acting injection of vitamin B12.
Results show some advantages
No significant difference was found in ewe body condition score between treated and untreated ewes, nor across any of the age groups.
There were no ewe deaths among the younger ewes. Among older ewes, there was a 10 per cent lower death rate in the treated ewes.
There was no significant difference in lamb survival between the treated and control group younger ewes. However, lambs from the treated older ewes had an 11 per cent better survival rate than their control group counterparts.
With regard to lamb docking weight, there was a 640g advantage in the lambs from treated older ewes.
While larger ewe numbers would have improved the quality of the results, the 10 per cent lower deaths in the treated older ewes was particularly noteworthy. The cocktail of products also had a positive effect on lamb survival and docking weight for lambs out of the older ewes.
It is most likely that the first two products – an injection of vitamin A, D and E, and a magnesium pidolate drench – provided the most metabolic protection, but the B12 supplementation would be beneficial where there are known deficiencies.