4 C's of Waste Milk Management

4 C's of Waste Milk Management

4 C’s of Waste Milk Management

Many calf raisers feed waste, or otherwise termed unsaleable milk, as a method of reducing feed costs. This method is viable, and calves often do very well on discarded milk, however, a few considerations to management of waste milk should be taken into account to ensure that calves are receiving a high quality and nutritious product.



You may already feed waste milk, or you may be thinking about it as a future possibility. One major thing to consider when deciding if this is a good feed source for you is of course the COST! Many dairy farmers consider waste milk to be free because it is not saleable. However, this is not the case. There is still a cost to harvesting and processing this milk to be fed to calves.

Often calf ranches will work out a deal with the dairies they pick up from to buy waste milk to be fed to the calves. This is still a cost though and purchase price, hauling, and processing should all be considered when comparing the price to milk replacer.

There are many good resources out there that can help you to determine if feeding waste milk is a good option for you. The AVA Group Inc. recently wrote some blog articles on their point of view of determining the value of feeding waste milk vs. milk replacer. You can find them here.



Monitoring the pathogen load of waste milk is essential in the prevention of passing disease on to calves. Measures that help to assess pathogen load include bacteria counts, Somatic Cell Count (SCC), and pH.

Bacteria Counts should be evaluated both pre and post pasteurization. The goal is to be feeding milk with SPC levels <20,000 CFU/ml. However, even if you may be meeting those goals post pasteurization, if pathogen counts were super high before pasteurization you are now feeding large amounts of dead bacteria to the calf.

We do not necessarily know the effects of feeding large amounts of dead bacteria to calves, however, we can speculate from studies done on other species. Although it has not yet been shown to be a problem in calves, studies in rats have shown that ingestion of high endotoxin levels from dead coliform bacteria may be harmful, especially if these endotoxins leak through the gut barrier into the bloodstream, causing systemic endotoxemia.

Best case scenario is to pay attention to cleanliness protocols around harvesting, transporting, storing, and feeding waste milk to ensure pathogen levels stay low.

High SCC is often associated with waste milk as it is harvested from hospital pens. Milk with high SCC is often associated with low milk solids and low milk protein. Best practices for reducing SCC of waste milk include management and improvements in the health and immunity of the lactating herd. In fact, it is probably a good sign if you don’t have adequate amounts of waste milk to feed all your calves. 

pH is one of the quickest and easiest ways to tell if the milk has spoiled. Normal milk pH is about 6.5. As the milk begins to spoil initially the pH will drop, and then it will rise depending on the stage of spoilage, time, temperature, and number of bacteria present. Discard milk with a pH of <6.3 or >7.0.



One of the major obstacles associated with feeding waste milk is consistency. Even on one farm, waste milk may come from many sources. Fresh cow milk, high SCC milk, milk from treated cows, diluted with wash water, and possibly even milk from different breeds of cattle. It is important to minimize the variability as much as possible to avoid digestive upset in the calves.

A Brix Refractometer is a handy tool for assessing variability of waste milk. A brix reading is not an exact reading of the solids level; however, it can be helpful in establishing a baseline for whether waste milk needs to be balanced with a milk replacer.

Periodic component testing is also beneficial in establishing an effective feeding protocol including waste milk. Like many other concepts in nutrition, although heavily based in science, there is some art to successfully feeding waste milk in a manner where calves perform well. 

Some calf raisers may choose to wait to feed waste milk to calves older than 2 weeks of age to avoid issues that may arise from any inconsistencies in their waste milk.



Evaluation of current research suggests that feeding waste milk containing antibiotics to calves may shift the intestinal microbiome, interfere with the proper formation of intestinal epithelium and mucosal later, disrupt formation of lymphoid structures and prevent the differentiation of immune cells.  Resulting in possible negative effects on the health of the calf as well as to the health of the global public.

In cases where milk that is tainted with antibiotics must be fed to calves it is always a good idea too provide a probiotic supplement that will help to nurture the calf’s microbiome and repair any damage that might be done to the intestinal wall. Feeding Surveillance Calf during the pre weaning phase and Tomahawk iL at weaning is one way to accomplish just that.

Future research may provide us some alternative treatments that may help reduce the contamination of discarded milk with antibiotics.


Calf feeding is not a one size fits all kind of business. While waste milk may work well for one operation, milk replace might be a better choice for another.  Crunch the numbers and account for management practices that may be needed if you were to choose to feed waste milk.


Written by: Mariah Gull M.S.

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