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Consider contract grazing dairy heifers for feed savings, freeing up space on the farm

Tamara Scully for Progressive Dairy Published on 11 September 2020
Grazing dairy heifers

Raising heifers in a conventional system can be an expensive undertaking. A. Fay Benson, grazing educator with the South Central New York Dairy Team, said he thinks there is a better way that might make sense for many large dairy farms.

For more than a decade, Benson has been researching contract grazing systems for raising dairy heifers and has demonstrated that managed intensive grazing (MIG) of replacement heifers is a cost-effective option for large dairy farms.



Managed grazing requires more than simply putting cows on pasture. Most large, conventional dairies are not equipped to undertake this type of intensive grazing themselves. Hiring a contract grazier and sending the heifers off the farm frees up labor, reduces the amount of animals for CAFO manure-handling regulations and has added health benefits for the cows.

The key to success for these relationships is a contract that spells out the terms of the contract including the average daily gain (ADG) expected, supplemental feed and minerals required, vaccination and parasite protections to be administered, safe animal-handling procedures, transportation agreements and contingencies in case of drought, sick animals or non-payment. Such a contract protects both the grazier and the dairy farmer, clearly spelling out expectations and setting the relationship up for success.

As a part of his research, Benson has compiled a comprehensive booklet, “Grazing Heifers: An Opportunity for Large Dairy Farms,” which outlines the benefits, concerns and practical details of contract grazing dairy heifers.

Benefits of grazing

Feed is the most expensive component of raising heifers in confinement and is about 51% of the total costs, according to Benson’s data. If the heifers can receive adequate nutrition via MIG, feed costs are substantially lowered on pasture.

In his studies of New York dairies, Benson found that those using contract grazing saved approximately 35 cents per day in feed costs and labor, based on 2016 data.


“I can’t imagine contract grazing ever being more expensive than confinement feeding,” Benson said. “Even if all the feed was fed (on pasture), the pasture method still has the advantage of not cleaning the barn and spreading the manure every day.”

Nutrition and intake from pasture forage changes daily, unlike the fed ration. Changes in forage density and composition will affect the nutrition available. There are enough nutrients in a typical cool-season pasture mix to provide for most of the heifers’ daily requirements. Supplementation to meet energy needs, as energy is limited on pasture, may be necessary at times to meet weight goals prior to breeding or calving. The expected daily rate of gain is specified in the grazing contract, with the dairy farmer supplying supplementation if pasture nutrition is inadequate.

Pastured heifers have been shown to have increased dry matter intake (DMI), which continues after they are returned to the herd for calving.

“I don’t know of any study that has looked at how long the increased DMI goes on after the animal is removed from pasture, but it is at least two weeks,” Benson said.

Benson put pedometers on grazed and confined heifers, and his studies have shown that grazing heifers are walking as much as 300% more than confined herdmates. This increased maintenance requires additional DMI. That additional DMI, when consumed over time prior to calving, has positive health benefits, he said, as the increased DMI seen with the grazed cows equates with less chance of an energy imbalance, which leads to subclincial ketosis and other health concerns.

Benefits to cow health for heifers in a managed grazing system include a reduction in early lactation health problems. Less calving difficulty and decreased incidences of metritis, ketosis and displaced abomasum (DA) have been shown in multiple studies when heifers are raised in a MIG system but returned to confinement prior to calving, as compared to those heifers kept in confinement.


Heifers grazing may not reach mature weight as quickly as those fed a ration in confinement. This can be compensated for by delaying breeding.

“To many dairies, the age at first calving is an easy metric to look at and, in my opinion, gets too much importance,” Benson said. “In organic and some grazing herds, they have opted to breed the animal one or two months later to allow the animals to be closer to mature weight before they calve.”

Benson himself has been a contract dairy grazier, grazing bred heifers only. He tested the nutrients available on the grazing sward and, along with an estimate of how much the cows were consuming, could calculate if the pasture forages were providing the needed energy. If they were not, the agreed-upon supplementation would be fed. In his experience, he had to supplement the cows for three of the eight grazing seasons that he contract grazed animals for a particular dairy. The supplement occurred in the last summer months and was fed using movable bunks.

Getting to grazing

Heifers cannot simply be put onto grass after being fed a ration. Contract graziers need to plan for a period of adjustment, when the heifers will continue to receive some TMR while on pasture.

“The animals learn faster if they are hungry. I would provide a limited amount of the TMR that the animals were used to, for three days, all of the time having access to grass,” Benson said. “The inexperienced grazier continues to supplement TMR, which prolongs the training and the period of weight loss. The goal is to get [the heifers] better at eating grass as quickly as possible so that the pasture grasses don’t get too mature and lack nutrients.”

Heat spells can reduce DMI, and graziers need to plan to control heat stress. Benson encourages graziers to move the animals into a shaded area for two to four hours during the hottest part of the day, to keep their body temperatures from rising.

“The pedometer study I did showed that for short-duration hot spells, the animals will increase grazing at night. Longer heat spells will reduce DMI,” he said. “It is not recommended to have shade in regular paddocks, since it has been shown to change the area where the animals put down their manure and it also reduces grazing time.”

Fly control on pasture is different than in barns. Feed-through fly control chemicals will pass into the manure and will harm the more than 300 species of beneficial insect species which live in manure. Pour-on fly control will last for two weeks, Benson said. A simple chute, where animals pass individually, allows for application and works for other sorting needs as well.

Benson also recommends salt blocks with selenium, moved from paddock to paddock, plus a molasses lick tub with ionophores and minerals for pastured cows.

Training heifers to fencing, as well as moving cows new to grazing, are two other issues contract graziers will need to be aware of when working with previously confined heifers.

While dairy farmers can opt to manage the grazing themselves, hiring out the job to a contract grazier is the most likely option for larger dairy farms. Contract grazing provides cost savings associated with removing heifers from the barn, including savings in feed, less manure handling, healthier outcomes during calving and the postpartum period, and more time to devote elsewhere.  end mark

Getty Images.

The Grazing Guide booklet is available here.

Tamara Scully, a freelance writer based in northwestern New Jersey, specializes in agricultural and food systems topics.