We are seeing some digestive upsets, so if you’re feeding more than 3-4kgDM supplement per cow per day to your milkers or dry cows then keep reading as this applies to you!
What sort of digestive upsets?
These range from gut stoppage – so a huge full rumen and no digestion, to diarrhoea (everything shooting through!) to acidosis, colic and a variety of in between conditions, all of which make the cow sick, and they can even cause them to be downer cows.
Points to remember to avoid digestive upsets for cows
1. Make any diet changes, including minerals, SLOWLY.
The ROT (rule of thumb) is no more than 2kg DM (drymatter) change in any one day, and then wait 2-4 days before you make another change. For example, if you want to move your cows up from 2kgDM maize silage/cow/day, to 6kgDM/cow/day, then you need to add 1-2kgDM/cow on day 1, wait 2-4 days, and add the next 1-2kgDM etc. How much you add and how quickly you change the quantity may be decided by how you feed the supplement – if it is split into two feeds, and all animals are allowed immediate access, then each cow will be more likely to get their ration and not be able to overeat. If you feed all the supplement at one sitting it is likely that the greedy cows will eat far more than their allocated ration and they are the ones who will fall sick.
2. Mineral supplementation
Maize is low in calcium and sodium, other supplements are low or high in magnesium and have varying levels of potassium and phosphorous. Particularly if a cow is milking she needs a daily input of calcium, magnesium and sodium to replace what is leaving her body as milk. Therefore you need to know what your dietary levels of these minerals are and balance them appropriately. If you ask your veterinarian they will be able to advise you.
If you are introducing or removing minerals from the diet, do it SLOWLY. For example if you are going to be giving 200g limeflour per cow per day, start at 50g and work up in 50g steps every 2-3 days so that you don’t affect the taste of the food drastically, and allow the cow’s metabolism to adapt to the changes.
Proper mixing of the diet components is important or some cows will eat all maize and others eat all palm kernel etc. If they do the latter they will probably be fine, but those eating all maize are more at risk of a digestive upset, particularly if the maize has a high sugar content.
All cows need to be able to have equal access to the food you are giving them. Some people feed out ahead of the cows before they enter the paddock, or on a new break – they all need to be let in at once, and you need a long enough feed area that everyone can get in easily. The same goes for feed pads.
As with all herd illnesses, prevention is much better than cure! If you are not sure what you should be feeding your cows don’t hesitate to ask. If your veterinarian does not know the answer, they will quickly be able to find out for you by consulting with other veterinarians in the practice who have specialist ruminant nutritional expertise.