Since they aren’t making money in the milking string, dry cows can be overlooked on a dairy farm. Yet good dry cow care leads to better performance after they calve.
“Potentially, for every dry cow, there are four cows that are milking more due to proper dry cow management. Making improvements for dry cows is going to pay for itself in time,” says Dr. Vicky Lauer, a member of Animart’s professional services veterinarian team.
Lauer points out seven focus areas of care for dry cows to prepare them for a successful entrance into the milking herd.
Treatment
A treatment with intramammary antibiotics helps resolve lingering mastitis and prevents new infections from occurring over the dry period.
To administer the treatment, first milk out the udder. Then clean and sterilize the teat end.
“Dry cow tubes come with a nice set of alcohol wipes. Use those. Otherwise you’ll take bacteria straight up into the teat,” Lauer says.
Use one tube per quarter. After infusing, massage the quarter to work the medicine into the mammary gland. Finish with a regular post-dip.
There are several dry cow antibiotic treatments on the market today. Most treat Staph aureus, while some will also treat different types of strep and penicillin-resistant strains.
To know which treatment to use, Lauer recommends taking a quarterly bulk tank sample. Pull a milk sample from the tank once a day for five days, freezing each one. Then send it to a lab to commingle the samples and run one culture. She suggests treating for the predominant pathogen.
Other considerations to keep in mind when selecting the treatment are the length of the dry period and the milk and meat withhold for the treatment. Make sure the hold is over before the cows enter the milking herd.
Teat sealant
Some farms will use bismuth subnitrate to seal teats at dry-off, while others won’t, Lauer says.
After the antibiotic treatment is infused, Lauer says, re-sterilize the teat end. Then infuse the sealant, but do not massage, as the product should not be pushed further into the udder. Again, finish with the post-dip.
This product has been known to clog filters after the cows freshen. Lauer suggests thoroughly stripping each quarter eight to 12 times before milking, and milk those cows into a bucket for their first three milkings.
Vaccinations
The dry period is a good time to administer vaccines. Respiratory vaccines should be used only for the right reason, she says. This vaccine will only aid the cow as she enters the fresh pen; it will not increase colostral antibodies to benefit her calf.
Vaccines can also be given to help fight mastitis and salmonella. Lauer recommends these if there is a history on the farm.
There are some calf health vaccines that can be administered to the dry cow to be passed along to her calf. This is only relevant if the farm plans to feed that colostrum to the calves; otherwise, there is no point, she says.
Timing is crucial with calf health vaccines because the cow won’t start moving antibodies from her bloodstream into the udder until five weeks before calving. It takes two to three weeks after vaccination to reach peak antibody production.
Lauer says the best timing is to give the vaccine seven to eight weeks before calving. If the cow has never been vaccinated before, it should receive two doses, with the first one given one month prior (12 weeks before calving).
Housing
According to Lauer, the ideal dry cow housing would provide 30 inches of bunk space per cow, water access, a non-slip walking surface and adequate space for the cow to lie down.
For now, it is suggested that far-off dry cows have 75 to 100 square feet per cow in a bedded pack, with close-up dry cows getting 100 to 300 square feet per cow. In a freestall, the stalls should be 51 to 54 inches wide and 9 to 10 feet long with a brisket board 72 inches from the curb.
The optimum bedding in a bedded pack is a sand base with straw and shavings on top. This provides good footing and comfort. A concrete base with straw and shavings is easier to clean, but it could be harder on a cow if she goes down. In either case, the bedding should always be clean and dry.
For freestalls, sand is clean and provides excellent cow comfort. Mattresses work too, but they have been found to result in more hock lesions.
Dry cows should not be overcrowded. Lauer suggests finding the monthly calving average and figure 25 to 30 percent more capacity.
“We want all cows to have access to feed at the same time,” she says. “A recent study showed a 6.5 pound per day increase in milk for the first 80 days when stocked at 80 percent versus 120 percent. That’s quite a bit more milk.”
Cooling
“Dry cows need to be cooled as well,” Lauer says. Dry cows are often neglected as most cooling efforts are focused on the milking herd. Although research shows a 2- to 11-pound increase in milk per day if dry cows are cooled. The largest response was seen in cows cooled with fans and sprinklers throughout the entire dry period, instead of just the pre-fresh group.
Cooled dry cows also show an increased immune system function and lower somatic cell count.
Calves born to cooled dry cows weighed on average 14 pounds more, and they maintained that advantage through weaning. They also had better colostrum absorption, increased immune function, conceived one service faster and produced 6 pounds more milk per day for 35 weeks.
“If you were to punch it into an economic equation, it is a win-win for everybody,” she says.
Feeding
Dry cows poorly regulate their energy intake. They can consume 40 to 80 percent more energy than required while dry, which puts them at risk for metabolic and health issues.
Lauer’s general recommendation for feeding is 25 to 30 pounds per cow per day; the bulk of which should be from forage (70 to 80 percent). The ration should have moderate energy density (0.6 Mcal per pound) with low levels of protein (12 to 14 percent) and starch (12 to 16 percent).
The ration should be fed at 55 percent moisture. Water can be added, and it should be processed adequately to prevent sorting. The feed should be palatable with no mold.
Depending on the farm, anionic salt can be fed three weeks before calving. This sends a cow into a slightly acidotic state, causing her to ramp up calcium release to keep her levels normal, Lauer says.
Forage options for dry cows include corn silage, alfalfa hay, wheat straw, grass hay, sorghum silage and corn stalks.
Corn silage tastes great, but it is high in energy and starch, and won’t provide much bulk in the rumen. Alfalfa hay also has a good taste, and it provides a decent fill factor, but it can be high in protein, potassium and calcium.
Straw is a commonly used forage for dry cows because it is palatable and has a good fiber length. It is very low in energy and can be combined with a higher energy feed. It can be challenging to work with, as it is very dry and hard to process.
Grass hay has a high fill factor and is moderate in protein and calcium, but its downside is that it is extremely high in potassium and should be limited to less than 30 percent of forage dry matter for this reason.
Sorghum silage is gaining in popularity. It is high in moisture, but should be limited to less than 50 percent of forage dry matter due to its energy and potassium levels.
Corn stalks are not as common in dairy as they are for beef cattle. It is excellent for bulk, but can contain high levels of ash (soil) and is difficult to process, leading to issues with sorting.
Body condition score
Body condition scores range from 1 to 5 with 3 being ideal. One point is equivalent to 100 to 140 pounds.
At the time of calving, cows should have a BCS of 3 to 3.5. They typically lose a half point in early lactation (2.5 to 3) and gain it back in late lactation (2.75 to 3.25). Heifers tend to be thinner with a BCS of 2.75 to 3.25 at calving.
From a visual standpoint, a BCS less than 3 is a pointy cow. A cow with a BCS of 3 is more filled out with a nice, sleek look. At 4 or higher, she looks slushy and more like a beef cow, Lauer says.
Over-conditioned dry cows with a BCS of 4.5 or greater typically have a longer interval to first heat, longer interval to conception, lower first conception service rate and lowest dry matter intake post-calving, which results in an increased risk for metabolic disease.
“With beef prices high, a lot of guys are shipping fat dry cows to not deal with freshening issues,” Lauer says.
By improving each area of dry cow care, the cows will be off to a better start after they freshen. PD
