Setting up the winter diet for freshly calved cows
Joe Patton, Dairy Specialist and Aidan Lawless, Dairy Farm Manager at Johnstown Castle, stress the importance of having a feeding plan in place for the winter milk herd, outline the 3 importance steps involved and discuss the diet of the Johnstown Castle Winter Milk Herd.
Feeding plan for winter milk herds
With the end-line now in sight for grazing, it is important that winter milk herds have a feeding plan in place for the coming months. This plan needs to take into account available forage quality, herd milk yield and calving pattern (proportion of stale versus fresh cows). Fresh cow diets should promote high milk solids production and good body condition to improve fertility. Stale milking cows need to be fed efficiently for their level of production, avoiding overfeeding that will lead to excess body condition and unnecessary feed cost.
There are 3 important steps:
- Test forage to establish nutrient content and intake potential
- Formulate a ration that balances energy, protein and fibre plus minerals
- Use milk records/calving dates to assign cows to correct feeding levels
Johnstown Castle Winter Milk Herd
For the Johnstown Castle winter milk herd, we aim to have a good quality base ration that will work well for high yielding and lower yielding groups alike. This simplifies feeding in the yard. The parlour is used to top up the high yielding group with additional concentrate. The feed ingredients used for the basic milking diet this year will be:
- 9kg DM of good quality grass silage (74% DMD, dry matter 34%, crude protein 14.5%)
- 5kg DM of high quality maize silage (33% starch)
- 3kg of a high protein (23% crude protein) coarse blend fed as part of the forage mix (this contains barley, soybean, beet pulp and distillers grains)
This diet provides enough nutrients for approximately 20kg high solids milk as a base level. Lower yielding cows receive a further 2kg parlour ration. Fresh cows receive up to 6kg additional parlour concentrate bringing their daily dry matter intake to 21.5kg on average. This covers the fresh group with enough energy (UFL) and protein (PDI) for a group average milk yield of 31.5kg, which is our target for December/January. The nutrient composition of the fresh cow diet is outlined in Table 1. Parlour concentrate is formulated for high energy at 18% crude protein equivalent and contains full minerals and vitamins.
Table1. Composition of the total diet fed to Johnstown castle winter milk herd (fresh group)
Notes on the total diet composition
- High UFL energy per kg promotes good milk solids and body condition. Good quality forage makes it easier to meet UFL intake targets
- Diet is balanced for protein fractions (PDIN and PDIE are similar). Total crude protein level can be reduced to 15.5% (from the standard 17.5%) as a result, saving on feed cost
- Total starch and sugar is 19% which is low risk for acidosis (>24% increases risk)
- Diet fibre level is 38% NDF and 23% ADF (indigestible fibre). Based on these levels there is no justification for including extra fibre sources (straw) in the diet (32% total NDF with 24% of total from forage is a guide for adequate fibre). We have fed this diet over numerous years in Johnstown with no digestive issues. Straw would dilute the energy content and increase cost of mixing
- The same principles outlined here can be applied to herds targeting higher milk yields from their fresh group- adjust concentrate inclusion levels, monitor NDF adequacy and PDI balance
The Johnstown Herd was established in 2003 to provide a base for winter milk systems research in Teagasc. For more information on the Johnstown Castle Winter Milk Herd click here