Diet Feeders are an essential tool to help manage spring grass sustainability

 Tue, 6th Apr, 2021

Diet Feeders are an essential tool to help manage spring grass sustainability

A balanced approach to feeding by supplementing fresh grass with diet feeding can result in improved output, improved health, and reduced carbon footprint for the farm and herd.

Sustainable dairy farming requires every animal on the farm to be productive, maximising kgs of milk solids sold per cow per year, and producing a calf every 365 days. Carrying too many non-productive animals means demand for extra replacement heifers and leads to high stocking rates on farms. Farmers need to maintain healthy productive cows, minimising lameness and culling while maximising kgs of milk solids sold per cow per year. To achieve this a correctly formulated diet feeder mix is essential to balance grazed grass.

How does the supplementation of diet feed support increased sustainability? High emissions of ammonia can be the result of grass grazed cows without a properly balanced diet to enable the cow to trap and utilise grass proteins. Without this, the cow will excrete this protein in their urine in a very volatile form resulting in high emissions of ammonia. Fresh grass is rich in protein and fast fermenting sugars, it can be low or high ranging from 10% dm to 22% dm in dry matter and low in structural functional fibre. This can challenge cows when fed leading to Sub Acute Ruminal Acidosis (SARA) and high ammonia emissions. Ammonia emissions are currently the biggest challenge to the environment from Irish grass based dairy farming.

Using a diet feeder can help reduce this by balancing fermentable energy in feed. Creating a mix from cereal grains, fibre from dry high DMD, dry silage and chopped straw fed for a short period morning and evening pre-grazing can balance the qualities of good grass in a consistent manner reducing ammonia emissions. This balanced approach allows the cow to utilise the qualities of good grass in a consistent manner while reducing ammonia emissions.

A balanced diet will reduce urine ammonia excretion and fix more nitrogen in the faeces of the cow where it can be used as a nitrogen source to grow grass, increasing faecal nitrogen in cows and then spreading it as slurry with low emission slurry equipment on pasture and silage ground will in turn help to reduce the amount of chemical fertilizer N required to grow grass.  

A dry silage, straw and cereal based diet feeder mixed buffer feed offered to cows for 30 minutes morning and evening will ensure better rumen function. This balanced feed will trap excess N from grass and enable rumen bugs to produce more microbial protein supporting milk production and milk protein production. The structural fibre in the diet feeder mix will also support butterfat production through early lactation.

Spring grazing cows are at a risk for developing acidosis and SARA.  Acidosis and SARA lead to drops in milk production, drops in milk fat% and lameness in herds. Body weight loss can occur in cows with SARA from the drop in appetite and the pain endured with drops in the feet. This body weight loss can be detrimental leading to infertility and excessive culling of cows in the herd.

Correct dry cow management is very important in reducing milk fever and metabolic diseases in cows around the time of calving. This has become even more important as farmers lift their soil fertility indexes on silage ground and grazing platforms. Potassium levels in silage are a major contributor to milk fever in recent years. A good diet feeder mix minimise this risk for dry cows, blending silage, straw, meal and minerals formulated to reduce milk fever and metabolic upsets. 80% of vetinary bills on dairy farms occur around the calving period and the correct diet will minimise these expenses.

Diet feeding has significant advantages to both dry cow and milking cow health and production, it stimulates appetite whether at grass or indoors, aids cows in maximising their potential in terms of fertility and milk solids production. Use of native cereals and home produced silages in buffer diets at grass help to make efficient environmentally friendly use of grass proteins and further reduces the carbon footprint of farms by reducing the use of imported fibres.

All in all diet feeding should be part of a sustainable profitable environmentally friendly way of dairy farming.