Endophytes are fungi that grow in pastures. While they produce a range of alkaloid products that aid in protecting the plant from insect attack, they can also cause considerable problems within your stock, namely Perennial Ryegrass Toxicosis (PRGT) also known as Staggers. These endophytes can also be present in Tall Fescue.
PERENNIAL RYEGRASS TOXICOSIS (PRGT)
The fungi (endophytes) build up in the plant stems, crown, seed heads and leaves, however it is at lower levels in the leaf. When the plant is stressed it releases the toxins and problems can occur. Firstly, to those eating long stalky ryegrass with lots of stem and seeds and secondly to those eating right down to the crown of the plant. Those grazing the plant optimally (neither too rank nor too short) are much less effected. Classic cases of PRGT occur when we see a summer rain on well eaten pasture… you get a regrowth that then either rapidly gets cropped down to the crown, or rapidly goes to head… both can present issues. In lactating cows milk can be reduced because of PRGT, in the last couple of weeks alone we have seen losses of 3 litres plus in some areas, particularly when paired with the sudden bursts of high humidity and heat as well. When endophytes are impacting cattle they will experience an increase in body temperature, causing a double whammy of heat stress on the days we have been having over 25 degrees. Clinical signs & symptoms
Vaso Constriction = heat stress
Reduced feed intake
Reducde hormone Prolactin = deacreased milk yield
Death - primarily from misadventure
If you notice any of these signs, call one of our ruminant experts to discuss adjusting the pasture rotation or including a toxin binder into your ration
We have seen many farms suffer with heat stress over the last few weeks. Keeping cows cool is top priority to maintain appetite and production. And don't forget to CHECK water troughs frequently!
Click >>Here<< for information on heat stress and some consequential impacts on dry cows and heifers from research out of the USA.
Find out protein, energy, sugar, NDF and much more to meet your summer growth targets. With the price spike of cereal grain, knowing the silage quality means we can better tailor grain usage. Send a silage sample into Forage Lab Australia for quick and accurate results.