The Harley Ogle-Gane family partnership farms 220 cows in South Taranaki. Mastitis has been a big problem over the years, and each year they have to cull about 10 cows that have severe mastitis that does not respond to treatment. This has a significant effect on the farm's profitability - not only do they lose potential production, but they also have the expense of unwanted animal health bills.
Harley noted that they were forever 'chasing numbers', unable to pursue a good replacement policy, and therefore needed to retain cows with high cell counts that they would rather have culled. In addition, their somatic cell counts were high, typically averaging over 210,000.
The family also runs a piggery, and it had been suggested to them that the cause of the mastitis was the pig effluent that they spread on their pasture. Seeking another opinion, Harley contacted Jackie Aveling, the animal nutrition manager for Altum.
'I examined Harley's whole farm system carefully, took soil and herbage tests and looked at his herd's blood test results.
'The trace element status in the pasture was very much in line with other results we see in the Taranaki. Two key elements were deficient - zinc and selenium.
'Zinc is essential for skin health, and is needed for keratin plug formation over the winter dry period. It also helps the body to defend against bacterial attacks. Selenium has many functions, and is important in the immune system.
'I recommended he use Taranaki Micromax Plus, starting immediately and carrying on through to dry off, starting again a month before calving.'
After taking up Jackie's advice, Harley reported a big reduction in mastitis cases. In addition, he somatic cell counts soon fell to an average of 160,000, a 25 per cent reduction. He also noticed a reduction in the number of lame cows.
'I used to have a vet at least once a month,' says Harley, 'but the cows' feet are awesome now. I haven't had a vet on the farm for ages.'
At the end of August Harley had blood selenium tests carried out on eight cows. Three were cows that had been in the main mob and had received Micromax Plus from 1 July. They calved on 25 July. Three were heifers that had never received Micromax Plus. The other two cows had received Micromax Plus before dry off, but had not had any access since then. These two cows had been induced.
The three treated cows had significantly higher selenium levels than the heifers or induced cows.
The treated cows had an average blood selenium of 770 nmol/litre. The induced cows had an average of 280 nm/litre and the heifers had an average of 220 nmol/litre.