Grazing Dairy Heifers Increases Profits

The dramatic rise in grain prices over the past six months has dairymen wondering how they can get the most bang for their buck, writes Peter Callan, Extension Agent, Virginia.
calendar icon 20 September 2011
clock icon 4 minute read

Producers are working closely with their nutritionists to maximise the use of home grown forages in rations to reduce ration costs. Over the past 20 years increasing numbers of dairymen have started to intensively graze pastures to maximise pasture as a source of feed.

Pasture lands are an underutilised and under managed resource on many farms in Virginia. Rotational grazing is a management concentrates animals within a relatively small area (paddock) for a short period of time e.g. 12 hours - 4 days for dairy cattle.

A pasture may be divided into multiple paddocks. The cattle are then moved to another paddock while the other paddocks are allowed to recover and grow. Animals are moved according to a flexible schedule based on number and weight of animals, the amount of land available, quality of forages in the paddock and forage consumption. Continuous grazing is use of one pasture.

Stan Pace, Agronomic Crops Agent with the Mississippi State University Extension Service, explained: "Cows are selective grazers. When put in a selective forage situation, they'll overgraze some spots and undergraze others. Over time, you will have poor quality grass and less total forage production."

Forage utilisation efficiency is the percentage of forage grazed on a pasture. Mr Pace said: "Using rotational grazing can increase efficiency up to 75 per cent over conventional grazing's 30—35 percent efficiency."

He said moving the cattle every three or four days yields a 50—60 per cent forage utilisation efficiency. "To increase efficiency to about 75 per cent, I'd move them every day."

To make the best use of rationally grazed pastures and optimise animal growth rates, supplementation may be needed.

Due to a lack of rainfall in the summer months, many pastures may not grow enough forage to meet the animals’ dry matter intake levels. Based on forage quality and quantity and desired rates of gain, many producers supplement the grazing heifers with silages, bypass protein, vitamins and minerals, etc. The goal is to achieve 1.75 lbs. rate of gain that is needed for dairy heifers to freshen at 24 months and weigh 1,250 lbs.3 Soil fertility plays a major role in determining the quantities of forage produced on pasture.

A current soil test takes out the guesswork and prevents the producer from under or over-applying lime and fertiliser, either of which will decrease your efficiency and profitability.

Virginia Tech soil test laboratory recommendations are based on research conducted for Virginia soils and climate. The type of grazing system implemented on a farm has major implications regarding pasture fertility.

Missouri researchers estimated that grazing animals recycle 75-85 per cent of forage nutrients consumed. An even distribution of manure throughout a paddock is required for productive plant and animal growth. Intensity of grazing rotations affects the manure coverage in paddocks. In a rotational grazing system there is an even distribution of manure because the animals are forced to consume forage in the paddock before being moved to another paddock.

The Missouri researchers calculated that under continuous grazing practices, 27 years would be needed to obtain one manure pile per every square yard within a pasture. Conversely, the pasture was divided into paddocks and a two day rotation was used; then two years would be needed to achieve an even distribution of manure within the paddock.

In times of surplus forage in a pasture, the hay can be baled and sold or stored for future use. Kentucky researchers have estimated that a ton of grass hay (fescue, orchard grass) removes 12 lbs. of phosphate and 50 lbs. of potash from the soil. If these nutrients are not replaced soil reserves will be depleted over time.

Consequently, there will be a reduction in crop yields. Soil testing determines the amount of fertiliser that needs to be applied to maintain hay yields. Cooperative extension agents can assist producers in the design of grazing systems for their farms. Numerous grazers have stated that the greatest challenge in implementing a grazing program on their farm is taking the first step which is splitting a pasture in half using temporary fence.

Once they see how easy it is to move the cattle from one paddock to another, they never look back. How many times on a dairy farm do the dairy cattle harvest their forage and distribute their manure for free? In an era of high grain, fuel and fertiliser prices, grazing heifers provides producers the opportunity to reduce their operating costs in a simple user friendly management system.

September 2011

© 2000 - 2024 - Global Ag Media. All Rights Reserved | No part of this site may be reproduced without permission.