The amount of Selenium available to cows from grass is not high enough to meet their dietary requirements, according to a recent Teagasc survey. This can have a negative impact on fertility.
It is an important trace element, but research shows that grass diets are only capable of providing dairy cows with 38% of this requirement.
When cows full diets are examined over the grazing period – they will only be provided with 58% of the total Selenium they need. This occurs as levels in grass and grass silage are quite low.
As a result, a number of problems may arise from Selenium deficiencies at farm level, including infertility, poor thrive and metabolic disorders can rise in dairy herds.
Conditions associated with a lack of Selenium:
- Infertility
- White muscle disease
- Weight loss
- Retained placenta
- Cystic ovaries
- Metritis (inflammation of the womb)
- Low Immunity causing issues with high somatic cell counts and increased incidents of mastitis
- Poor Thrive
- Anoestrus
- Early and late embryo death
Prevention is better than cure
The quantity of Selenium present in grass can be increased by using a fertiliser enriched with the mineral.
Positive impact of using a Selenium-enriched fertiliser
Brian Doheny is a dairy farmer from Co. Kilkenny and the fertility of his herd has seen a marked improvement after using a Selenium-enriched fertiliser, according to Goulding Fertilisers.
Doheny started using the Gouldings Product Selenigrass, which is a CAN fertiliser containing Selenium.
Between 2014 and 2015, there has been a marked improvement in the fertility of the dairy herd, it says, as the empty rate on the farm fell from a three-year average of 8% to 4.6% in 2014 and 6% in 2015.
The first service to conception rate also rose from the three year average of 47% to 63% in 2014 and 70% in 2015. This is a 34% and 49% increase respectively in the number of cows conceiving to the first service, Goulding Fertilisers says.
It also says that one of the benefits that Brian experienced was the increase in normal repeat intervals which increased by 41% in 2014, compared to the previous three year average.
The high number of short and prolonged repeat intervals was a constant problem when it came to heat detection and service cows. As a result of increasing the Selenium level in the grass the calving interval has gone from 382 days, 370 days and 363 days over the last three years.
It says there has also been a marked reduction in the number of cows that have retained cleanings on the Doheny farm, previously the farm had between 10-20% of cows retaining cleanings annually, but in the spring of 2015 only four out of 170 cows presented with retained cleanings. All four had stressful calvings either having twins or big calves coming backwards.
Essentially however it all boils down to cost and Brian is now supplementing selenium into the diet through fertiliser at between 16-20% of the cost to farm profit in relation to previous methods.
“It’s a cheaper, easier, cleaner more effective way of supplying the mineral to the cows, I definitely wouldn’t go back.”
Gouldings also says that its Selenirange range is the only selenium fertiliser on the market which combines two forms of Selenium.
The fertiliser product provides both a quick acting and long lasting selenium to the plant which provides season long selenium for the animal, it says.
‘Seleni’ range fertilisers should be spread on both silage and grazing ground as part of the Goulding Selenium Programme, which requires four bags per acre to be spread over the season.
In association with Gouldings.
