As considerations move to autumn calvers, I am currently assessing the overall diet of these animals to ensure they are correctly balanced so as not to compromise milk production, health or body condition score. At present, I am visiting some herds that are possibly facing a situation of carrying too much weight which can bring its own problems – not uncommon for this time of year.
Body Condition Score
I recommend to body condition score (BCS) all cows in the herd and to cut back feed accordingly if cows are above BCS of 3.5. If cows are in BCS 2-2.5 in the pre-partum period it is critical that a high energy dense diet is offered to get cows at optimal BCS of 3.0.
Mineral balance is also critical to the health and subsequent reproductive performance of the herd. The inclusion of minerals in dairy and beef diets is extremely important under any production system to ensure efficient milk production and overall health. The major element requirements include Calcium, Phosphorus, Magnesium, Potassium, Sulphur, Sodium and Chloride but it is important to know the role that these elements play.
Important Minerals for Calving Cows
Calcium and Phosphorus are very important for bone formation. The inclusion of Magnesium is very important for dairy cows in the prevention of grass tetany during periods of stress or inclement weather conditions that can come at autumn time.
A general rule of thumb I refer to is provide dairy cows at grass at least 56 grams per head per day in the form of calcined magnesite.
Reduce Mineral Deficiencies
For electrolyte balance and cellular metabolism the inclusion of Potassium and Chloride is very important to help prevent metabolic disorders such as ketosis, metritis or displaced abomasum’s. Trace elements such as Copper, Zinc, Manganese, Iodine, Cobalt, Selenium and Iron are also important, as a deficiency in any of these will have severe consequences in terms of reduced live weight gain, infertility, delayed oestrus, retained placenta and higher incidence of metabolic disorders.
Copper is particularly important for hair coat colour, while Selenium and Iodine are important for optimum fertility. In order to have a good hard hoof for beef and dairy animals the inclusion of bioplex Zinc will help together with Biotin to strengthen and reduce lameness.
It is important to note that energy and protein metabolism will be compromised if a mineral deficiency is prominent. Vitamins also play an important role in the calcium absorption, strength of bones, immune function and foetal development. The most important vitamins include A, D, E and C. In particular, vitamin E has been shown to have positive effects on fertility and is a great antioxidant vitamin in boosting immune function.
I always stress the importance of matching minerals to the animal’s requirements. Most minerals are incorporated in the finished feed of either coarse rations or concentrates that I recommended to my farmers. However, I always draw attention to the feeding rates for optimal mineral intake to avoid any deficiencies or problems. For pre-parturition cows it is important that supplementation of minerals is given at least eight weeks prior to parturition.
When formulating an autumn grazing buffer feed, the same principles apply as those used in the spring. Since grazed grass is still the cheapest form of feed available, I consider any chance to keep the milking herd grazing through the autumn worth taking. Maintaining dry matter intake is the key to successfully incorporating autumn grazing into the diet. Low dry matter grass will require additional digestible and structural fibre to maintain good rumen function, while high grass rumen degradable protein (RDP) levels will need to be balanced with additional energy, and overall protein supply topped up with rumen-bypass protein.
High Energy Dairy Cow Feed
This is where I recommend using either a 16% or 18% high energy dairy cube. As energy will be the limiting factor at grass it is important to offer an additional source of energy and a reasonable level of protein to offset the decline in protein proportions in autumn grass. For dairy cows it is important that cows are offered feed according to BCS and a high dense diet is offered immediately post-partum with plenty of fibre to encourage optimum rumen. This must be done by the inclusion of extra supplementary feeds and the correct mineral balance. In my experience, buffer feeding in the milking parlour through offering concentrates or a coarse ration is an ideal way to achieve this.
Have Your Calving Facilities Ready
I always find it worth highlighting that careful attention must also be directed towards the hygiene of livestock facilities for autumn calving cows. With moderately high temperatures, bacteria can grow exponentially leading to mastitis or other infections.
Be On Calf Watch
Constant monitoring must be ongoing to avoid any problems that may arise for the autumn calving herd, however it is pivotal that to minimise the risk of these associated problems, correct management and planning at this time of year is key to a successful autumn calving programme.