Animals,  Farms

What to ask when you’re buying a dairy cow

Buying a dairy cow for the first time is a big deal! We bought 2 cows from trusted friends (thankfully!). Had we purchased from any stranger off of Craigslist, we might have purchased a dud cow. There are so many things to know about a dairy cow and keep the milk safe! Keeping a dairy cow healthy has been a huge learning curve for us. This is what we have learned, and what we will ask the next time we purchase a cow. (By the way, the cow in the picture is Violet, who gives about 6 gallons per day. She’s a Jersey and a good cow!).

Has she been tested for TB (tuberculosis) within the last month?

  • You will want to see proof that she is free of tuberculosis. You do not want a cow with TB.
  • She will be contagious and you and your other animals may get it just by breathing the same air or by exposure to her stools.
  • When TB gets into your soil, it takes about 8 weeks for it to die.
  • Cows that are poorly nourished, under stress or lacking sunlight have higher rates of TB.
  • Cows from intensive dairies are a lot more likely to have TB.
  • Typically, when a cow is found to have TB, it is slaughtered.

Is she free of Johne’s Disease?

  • Again, ask for proof that she has been tested and is healthy.
  • Johne’s (Yo-nees) is equivalent to Chron’s Disease in humans. It creates a lot of diarrhea and a lack of mineral absorption.
  • It is highly contagious to other cows.
  • It survives pasteurization.
  • It is rampant in the dairy industry.
  • Cows are more likely to get Johne’s if they are kept in an unclean environment or are exposed to water sources that contain manure.
  • There is no cure for Johne’s Disease.

Has she had the Brucellosis vaccine?

  • Brucellosis is also called “Bang’s Disease” and it is referred to as “contagious abortion.”
  • Although it is extremely unlikely, some believe that Brucellosis can spread to humans through consumption of raw milk. If you own a raw milk dairy and someone gets Brucellosis from your farm, your operation will be shut down.
  • It is best to have your cow vaccinated so that if a human who has consumed your cow’s milk gets something like the human form of Brucellosis (Undulant Fever), you can show the proof of vaccination.
  • Dairy herds in the US are tested once per year for Brucellosis. If they have the disease, they are killed.
  • There is no cure for Brucellosis in a cow.
  • A cow should be vaccinated for Brucellosis between the age of 4 and 6 months for best results.
  • Ask for proof. (The cow may have a tattoo that signifies that she has been vaccinated).

Has she been tested for Staph A?

  • Staph A is spread from cow to cow by flies.
  • You cannot have Staph A on your farm and also produce cheese for sale. You will be shut down.
  • You can potentially clear Staph A with antibiotics, but once it gets to the udders, you are out of luck.
  • You can keep Staph A out of the milk only by cleaning the cow carefully with a teat dipper and drying her teats off.
  • If you have any other cows, you’ll have to isolate the Staph A infected cow. You’ll have to use the milking equipment on the Staph A cow last and sterilize everything before using it on another cow.
  • If a cow has Staph A, it is probably best to butcher her.

Has her milk recently been tested for the following diseases:

       E.coli 157H7
  • E.coli 157H7 is typically due to high levels of grain consumption.
  • It is spread through the feces of infected cows.
  • There are no known methods of controlling E.coli 157H7 in cows.
  • If a cow’s milk contains E.coli 157H7 it is dangerous to drink and can make people very sick.
  • Culled cows that have E.coli 157H7 are not safe for human consumption.
  • If a human contracts E.coli 157H7, antibiotics are ineffective and will likely do more harm than good.
  • Salmonella is usually spread through feces, flies, birds, rodents, pigs, cats and dogs.
  • Salmonella is typically due to high levels of grain consumption.
  • It lives for 4 to 5 years in the soil, water and dust!!!
  • Any crops that are fertilized with the cow’s manure will be dangerous to consume.
  • Salmonella is found more often in confined commercial dairies.
  • Animals that are stressed or poorly fed are more likely to get Salmonella.
  • It causes decreased milk production, lethargy, dehydration, diarrhea and increased salivation.
  • A cow can carry and “shed” Salmonella for up to 18 months even if she does not show any symptoms of the disease. During this time, she is contagious to other animals that live near her.
  • Giving the cow antibiotics may extend the length of time that the cow carries the disease or make it worse.
  • Even though all of this sounds scary, the risk of getting Salmonella from drinking raw milk is low. Between 1998 and 2008 there has not been one single case of Salmonella that was linked to raw milk.
  • Camphylobacter is spread when an infected bull mates with a heifer.
  • Campylobacter is typically due to high levels of grain consumption.
  • The disease creates low rates of conception (about 40% reduction in the rate of conception) abortions, and long and difficult calving.
  • Campylobacter in milk can make humans very sick with diarrhea.
  • There is no cure for Campylobacter in a cow.
       Listeria Monocytogenes
  • Listeria Monocytogenes is almost exclusively due to the cow eating moldy silage or hay.
  • It is a disease that typically occurs in the winter and spring in cows that are kept indoors or on feedlots.
  • It is spread in the feces, the milk and possibly the urine.
  • If Listeria is caught early, it can be treated with high doses of antibiotics for at least 6 weeks.
  • If a Listeria is caught after a cow is symptomatic (showing depression, lethargy, facial paralysis, excessive salivation, still births or abortions and/or a fever), or if Listeria gets into the udder of the cow, she will need to be butchered.
The above questions may be all that you need. If you find out that the cow has a serious disease, you will want to stop. Do not buy this cow. Move on, you’ll find another one! If she is free of serious diseases, keep going and ask the following questions: 

Has she had Mastitis?

  • There is a good chance that she has had Mastitis at least once, but you don’t want a cow who gets Mastitis often.
  • Every time she gets it, you will need to treat her (either with antibiotics or an alternative method) and dump her milk. You will still need to milk her, which means wasted time and energy, and loss of a good product (and money, if you’re selling the milk).
  • Cows are more likely to get Mastitis if they are undernourished, stressed, or if they are not milked on a regular schedule.

How old is she?

  • If you are a beginner, you’ll want to purchase a cow that is at least 3 years old and no more than 7 years old.

How many calves has she had?

  •  It is best for a beginner to purchase a cow that has calved once or twice before and has been milked.
  • A cow should be having 1 calf every year after she is 18 months old, so this will help you determine if her age is correct.
  • If a cow has not be calving every year, then ask why. She may be difficult to breed (and in that case, probably not the best cow to purchase).

When was she last freshened?

  •  This means, when was she last introduced to a bull or when was she last artificially inseminated?
  • It is best to purchase a cow that is pregnant.
  • It is best if she is about 6 months along (so that she will be due in about 3 months, and it has been confirmed that she is carrying a calf).

How much milk does she produce?

  • This will vary based on her breed. Make sure she is producing a decent amount of milk for her genetics.
  • Many dairy farmers will sell (or “cull”) the cows that produce the least. This might be an ok cow to purchase for a family who does not intend to sell their milk. Just remember, you will still milk the cow 2 times per day, clean the equipment, feed her the same amount of hay, alfalfa and grain, pay the same amount for her hooves to be trimmed and for her vet bills as you would if she was producing a lot of milk. Consider these factors when deciding to purchase a cow that produces a low volume of milk.

Has she been milked by hand or machine?

  • The safest, cleanest and least taxing way (for the milker) to milk a cow is with a machine.
  • Machines are about 30% more efficient at getting milk out of a cow than the human hand.

Does she kick?

  •  You don’t want a cow that is going to be dangerous to milk or to have children around.

Does she require a stanchion?

  •  If so, at least you can have one ready for her. You don’t want to attempt milking without one if she needs it.

What is her temperament like?

  •  This is important. You don’t want a cow that is mean, or belligerent, or even too skittish and shy. You want a gentle, friendly cow.

Are all 4 of her teats normal?

  •  It is possible to milk a cow with abnormal teats, and you will likely find such a cow at a good deal.
  • However, it will take more time, will not be easy to milk the cow by machine, and the cow may produce less milk because of this issue.
  • It is best for a beginner to choose a cow with 4 normal teats.

Does her udder have any lumps or abnormalities?

  •  This can be a sign of Mastitis, and you do not want a cow that is prone to Mastitis.

Has she ever had a halter on her?

  •  If you plan to use a halter on the cow, it’s good to know if one has been used with her before.

What kind of feed and supplements has she been getting?

  • It is good to know this so that you can give her the same feed and supplements as she transitions to your land.
  • Changing a cow’s feed, supplements and grass/soil (with new bacteria) all at once can be upsetting to a cow’s digestive system.

Why are you selling her?

  • As with any used item that you’re purchasing, ask honestly why the owner is selling this cow.
  • The best cow will come from someone who just has too many cows (in Oregon we can only have 3 dairy cows–so somebody who has 4 will need to sell one), or from someone who is getting out of the dairy business completely.

I hope that this information is helpful to you! Good luck and enjoy your dairy cow! 🙂

photo credit: DonkeyHotey

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  • Somethings Cookin

    Hmmm, I thought freshening was when the animal delivered their young? Are you sure it means when she was with a bull?
    Also, if you’re trying to avoid BPA or plastic in general, using a machine and putting all the nice warm, fresh milk through plastic tubes in the machine seems unnatural to me. I did consider it when we were training our cow, but the drawbacks seemed as many as the benefits, so we opted not to. Everyone’s needs are different, but for us, having the raw milk came about because of wanting to get away from everything industrialized and the associated toxins, so the machine is out..
    One more question to ask might be whether or not the seller is willing to let you milk her. If you’ve never milked an animal, perhaps even asking for a lesson would be in order (though I would expect to compensate the seller for this added bonus). If the seller is unwilling to do this (and I can see valid reasons to say no) find out why if you can. It MIGHT be an indication there’s a problem with her. If it’s the dry season for that animal, obviously there’s no milk. I’m rambling now so I’ll stop here.
    Thanks for a well written article.

  • Jennifer

    Hello. Just came across your post. We are thinking of buying a dairy cow. Your post was very helpful on things to ask and look for. I was just wondering why I wouldn’t want a cow that is more than 7 years old?
    Thank you, Jennifer

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