Phosphorus (P) deficiency can be exacerbate by a dry/cold spell in April according to Dr. Joe Patton a dairy specialist with Teagasc.

April has seen dry weather conditions in most areas of the country, with temperatures also dropping from the highs experienced last week.

Grass growth is slow on many farms, with many farmers now hoping for rain to allow for the burst of grass growth usually seen in April.

Phosphorus deficiency – what to look for?

If you think your cows may be deficient in P here are some of the possible signs that Joe has said to look out for.

According to Joe: ”If your milking cows are licking walls or chewing stones, this is most likely due to a deficiency of P in the diet.

”Interestingly, this is not confined to farms with low soil P index. A dry/cold spell in April can exacerbate the problem,” he added.

What to do if these symptoms arise?

What can you do if your cows are showing some of the symptoms of P deficiency outlined above?

Joe stated: ”Firstly, the problem should not be ignored. P deficiency problems can have a major negative effect on conception rates over the coming weeks.

”Supplement cows with 8-10g of additional P per cow per day.

”This can be included in the next load of concentrate, added to water troughs daily, or through high P salt licks placed in the field,” he added.

”As the grass growing season progresses and herbage P returns to normal, it will be possible to remove this additional supplementary P from the diet.”

To analyse the problem further

Joe has outlined some steps which will allow you to analyse the problem further and determine if P deficiency is an issue on your farm:

  1. Consult your vet and blood test eight to ten cows a mix between earlier/later calved and heifers/mature cows;
  2. Test three sample paddocks for herbage mineral levels. Cut to 4cm as per usual guidelines for grass sampling.