Vinegar in Your Chickens’ Water — Good Idea or Not?

Understanding whether or not vinegar in your chickens’ water promotes flock health requires first understanding pH. In case you missed, or forgot, this part of chemistry class, let’s start with a quick review.

The pH Scale

The acidity or alkalinity of any substance is measured on a pH scale. Low numbers are acidic and high numbers are alkaline (also known as basic).

A pH scale typically runs from 0 to 14. Each number is 10 times more alkaline than the previous number.

Pure water is neutral and has a pH of 7. Working toward lower numbers, a pH of 6 is 10 times more acidic than pure water. Working toward higher numbers, a pH of 8 is 10 times more alkaline than pure water. A substance with a pH of 1 therefore is strongly acidic, while a substance with a pH of 14 is strongly alkaline.

Crop pH

Most pathogens thrive in a pH range between 7.5 and 9 and cannot tolerate an acidic environment. Beneficial bacteria (probiotics) generally prefer a pH range of 5.5 to 7.

The pH of a healthy chicken’s crop lies between 5 and 6. Within that range, beneficial bacteria inhabit the crop and produce lactic acid.

Lactic acid keeps the crop at its healthy, slightly acidic pH level. Ingested pathogens therefore have a hard time making it past the unfriendly — to them — crop environment. Routinely acidifying the drinking water of healthy chickens therefore offers no benefit.

Vinegar pH

On the other hand, an ill or injured chicken, or one otherwise under stress, may drink less than usual. Insufficient water disrupts the activity of beneficial microbes throughout the digestive tract, starting at the crop. A decrease in the population of beneficial microbes encourages an increase in the population of pathogens.

Vinegar is a natural antimicrobial with a pH of about 2 or 3, depending on the type of vinegar. Empirical evidence suggests that chickens like the taste of slightly acidified water, which therefore encourages them to drink more. But adding too much vinegar can have the opposite effect, causing chickens to stop drinking.

A good place to start is one tablespoon of vinegar per gallon of water. Since water can be slightly acidic or slightly alkaline, you may need to adjust the amount of vinegar based on the water’s original pH. Your goal is to adjust the pH level of the drinking water to about 4. You can determine the water’s pH by using either a pH meter or pH test strips.

While encouraging an ailing chicken to drink, vinegar also helps restore the crop’s acidity. Acid-loving beneficial microbes are therefore encouraged to return, crowding out alkaline-loving pathogens.

Adding vinegar to your chickens’ drinking water has the additional benefit of discouraging the growth of pathogens in the water itself. In a disease outbreak, when healthy and infected chickens drink from the same water, vinegar can help slow the spread of disease. Some common diseases for which vinegar acidified water can be beneficial include coccidiosis, canker, and pox.

Vinegar, used full strength, also makes a good sanitizer for cleaning feeders, drinkers, and other equipment. Vinegar’s acetic acid kills most bacteria and many fungi and viruses.

Vinegar and Chicken Digestion

When feed from the crop moves down to the chicken’s stomach (proventriculus), it encounters a much more powerful acid than lactic acid. Hydrochloric acid in the chicken’s stomach reduces the pH range of digesting matter to between 1 and 3.

But stress or illness, besides causing a chicken to drink less, can also cause the chicken to lose its appetite. And an empty stomach does not produce acid. As a result, the stomach’s pH goes up. The increased pH discourages beneficial bacteria and encourages a proliferation of pathogenic bacteria.

One of the first signs that digestive pH is too high is the appearance of loose droppings. Not incidentally, loose droppings may also be a sign that the chicken is drinking a lot of water (typically in hot weather) or eating an abundance of juicy foods.

But if the chicken isn’t drinking or eating much, offering the bird vinegar acidified drinking water to encourage it to drink more also encourages it to eat more. Food in the stomach restores digestive pH balance.

What Kind of Vinegar?

To qualify as vinegar a liquid must be at least 4 percent acetic acid. Most household vinegar — whether made from apple cider, distilled vegetables and fruits, or distilled petroleum — contains about 5 percent acetic acid. The pH of white vinegars generally ranges from 2.3 to 2.6, while slightly less acidic cider vinegars have a pH range of about 3 to 3.3.

Among chicken keepers, raw apple cider vinegar is touted as being superior to pasteurized or distilled (white) vinegar because raw vinegar contains a live culture. This culture, known as mother of vinegar, consists primarily of acetic acid–producing bacteria, or acetobacter, which require oxygen to survive. The crop’s lactic acid–producing bacteria, on the other hand, require an oxygen-free (anaerobic) environment.

After a chicken swallows raw vinegar, the live acetobacter can’t last long upon entering the crop’s anaerobic environment. Any other beneficial nutrients that might be in the mother are in such small amounts as to be inconsequential to the chicken’s health. So for practical purposes, the type of vinegar you use in a chicken’s drinking water is immaterial.

When to Use Apple Cider Vinegar

Every rule has an exception, and here is this one: If you are treating a chicken with a respiratory disease that produces mucus in the mouth and throat, use apple cider vinegar. Apple skins contain tannin, the same type of astringent compound found in coffee, tea, and red wine that makes your mouth feel dry.

The same property gives a sick chicken relief by helping clear the mucus from its mouth and throat. So the ailing bird will benefit from apple cider vinegar added to its sole source of drinking water until the condition clears up.

When Not to Use Vinegar

As you can see, adding vinegar to an ailing or stressed chicken’s drinking water can be beneficial. But adding vinegar to a healthy flock’s drinking water serves no purpose.

Additionally, and pay attention here: Acidifying the drinking water during hot weather is decidedly detrimental to hen health. For details on why you should never use vinegar in your chickens’ water during hot summer days click here.

Another time not to put vinegar in the drinking water is if you use galvanized water founts. The zinc coating naturally oxidizes over time, causing the metal to rust. Vinegar creates a chemical reaction that speeds up the rate of oxidation.

On this subject, the American Galvanizers Association says that vinegar affects the appearance of the galvanized coating “in some way,” without specifying the type of vinegar or in what way it affects the coating. But elsewhere on the same page they note that white vinegar does not damage “the galvanized coating or the appearance.” I’m not exactly certain what their contradictory point is, but have included here for the sake of thoroughness.

At any rate, expensive galvanized drinkers don’t last long to start with, so speeding up the rate of oxidation doesn’t seem like a good idea. Further, without knowing the exact nature of the chemical reaction, I can’t be sure how it might affect a flock of chickens.

In case you’re wondering, I use galvanized drinkers and I do not put vinegar in the water. Until I see convincing scientific evidence to the contrary, logic tells me that the routine use of vinegar has no benefit for a healthy flock. My chickens seem to remain perfectly healthy drinking the same thing I do — plain water straight from our well.