Improving caprine milk quality

Milking routine problems and equipment issues were two of the top areas for improvement according to a parlor audit of 16 goat dairies in Vermont. These issues, including problems with vacuum levels, pump capacity, teat end cleanliness and more, were found in 94% of the farms studied.

A webinar discussing this milk quality research was put on by Sustainable Dairy Goat Agrisystems. The webinar titled “Improving Goat Dairy Milk Quality: Lessons from Parlor Audits in Vermont,” was presented by Kelsie Braam and Whitney Hull, dairy specialists with the University of Vermont Extension.

The 2024-25 small ruminant dairy development and milk quality project studied 16 farms in Vermont. It was the second round of goat dairy research and technical assistance done by UVM.

“The main focus was diagnosing milk quality issues on farms,” Hull said. “We also conducted interviews with each participating farm as well. We had a mix of both farmstead creameries as well as farms shipping fluid milk to a processor.”

On-farm testing and parlor audits were conducted with Dr. Paul Virkler of Cornell’s Quality Milk Production Services and completed between December 2024 and September 2025.

“After we conducted the parlor audits, Cornell made really lovely reports, and we had follow-up visits with each farm where we could sit down and present the results to them and answer any questions that they might have,” Hull said.

The primary services available from QMPS to determine dairy milk quality were conducting a parlor audit and a wash analysis.

The parlor audit was designed to troubleshoot environmental mastitis issues and high cell counts while observing the milking routine. Milking routine observations included scoring teat ends and checking for cleanliness, timing of the milk routine, observing unit alignment, observing pre- and post-dip coverage, analyzing milk flow and scoring udder hygiene. Milking equipment was also tested, including the pulsators and vacuum line.

The purpose of the wash analysis was to troubleshoot high bacteria counts. The analysis observed the routine after milking, including water temperature, chemical concentrations, slug speed and vacuum drop. The sanitizer routine was also analyzed and water was tested.

Four milk bacteria tests were performed, including the Standard Plate Count, Preliminary Incubation count, the Lab Pasteurized Count and the Coliform count.

SPC indicates the total number of aerobic bacteria present in the milk at the time of pick up. PI reflects milk production practices with milk held at 55 degrees for 18 hours before plating. LPC estimates the number of bacteria in milk that can survive pasteurization. Coliform count measures bacteria that are most commonly associated with manure or environmental contamination.

The findings discovered three locations for potential milk quality issues in the parlor audit and the wash analysis.

The parlor audit discovered threats to milk quality in milking equipment, milking routine and mastitis.

“Dr. Virkler ranked all farms and gave them three priorities,” Hull said.

Equipment issues were the top priority in 56% of farms tested, with 88% of farms having equipment issues in their top three priorities. Threats to milk quality included vacuum levels, pulsation rate and pump capacity.

Milking routine was a top priority on 38% of farms, and 81% of farms saw the milking routine as a top three priority. Threats to milk quality in this stage were teat end cleanliness, post-dip coverage and lag time.

“Farms were doing a really good job of cleaning the barrel of the teat, but when we used an alcohol swab on the very bottom of the teat, we were still finding that a high percentage of those were dirty,” Hull said.

Mastitis was a threat to quality, but below the level of the prior two. Six percent of farms had mastitis as a top priority issue and 31% of farms had it as a top three priority.

“That wasn’t a huge finding,” Hull said. “We weren’t testing every animal on every farm; we were spot testing some animals.”

The key takeaways of the parlor audit were pulsator and vacuum settings, teat end scoring, teat end cleanliness, milking unit alignment, post-dipping, Staphylococcus aureus management and milking routine lag time. It was deemed that lag time during the milking routine needed further research before reaching a conclusion.

“To prevent teat end damage, you should maintain proper vacuum and pulsation settings,” Hull said. “Replace your inflations per manufacturer recommendations for those producers that maybe don’t reach the number of milkings at least once per year. If you milk a traditionally yearly lactation, before those animals kid, it would be great to change your inflations.”

The three threats to milk quality in the wash analysis included mechanical, water and chemical issues.

Mechanical issues included the slope of the milk line, the air injector, bulk tank cooling and the length of the downspout into the bulk tank to reduce splashing. Twenty-seven percent of farms tested had mechanical issues as their top priority, with 45% of farms having mechanical wash issues in their top three.

Water issues were broken down into three categories: bacterial, temperature and volume. These included Pseudomonas, inadequate water volume and low water temperatures.

“We did not test water on every farm,” Hull said. “I wish now that we had, but we tested nine farms and six were positive for Pseudomonas. This isn’t something that is typically tested if you have a state water testing requirement. … If you’re interested in testing your water for Pseudomonas, you typically test water from the well, or as close to a source to the well as you can, then hot water and cold water in the milkhouse.”

Chemical issues included low chlorine levels due to water hardness. No farms had chemicals as their top issue and just 18% were found to have chemical issues in the top three of priorities.

The overall threats to dairy goat milk quality in the wash analysis were Pseudomonas, hot water, air injectors, slope of the milk line, wash water volume and the timing of the milk filter replacement.

Through the findings on these Vermont farms, Hull encouraged goat dairy farmers listening to the webinar to consider whether any problems or opportunities for improvement exist within their own setups.