Brushing up on dairy farming

Last Saturday was the annual open house at the UBC Dairy Education & Research Centre. Despite the light rain, we got an estimated 870 visitors, many on bicycle! In addition to drinking free chocolate milk, our guests learned about dairy farming and research on animal welfare, reproduction, and nutrient management.

Along with UBC honors undergraduate student Savannah Goldstein and PhD student Ana Carolina Moncada, I talked with our visitors about grooming behavior and brush use by dairy cattle.

Previous research has shown that grooming is an important natural behavior for cattle. Grooming behavior includes licking or scratching themselves, licking each other to form and maintain social bonds, and rubbing against objects such as trees, fences, or other surfaces indoors. When cows are given access to brushes, they spend more time grooming themselves, especially on otherwise hard-to-reach spots such as around the tail. Most research has focused on adult cows, and an increasing number of farms invest in automated rotating mechanical brushes.

Non-rotating brushes for heifers

Savannah and I are currently conducting 2 experiments with weaned heifers about 5 months old. We are giving the heifers small, non-rotating grooming brushes, which are in fact scrub brushes from the hardware store costing $18-20 CAD ($14-16 USD) each.

For Savannah’s thesis project, we are evaluating the heifers’ preferences for brushes mounted on the wall of the lying area in their pen, which is an open space with deep sawdust bedding. We are comparing how much the heifers use brushes with different orientations and bristle stiffness levels: stiff (similar to a dandy brush for horses) vs. extra-stiff (like those on the rotating cow brushes).

In our other study, we are investigating whether mounting brushes inside the freestalls can encourage heifers to lie down correctly when they first move into that type of housing system. With freestall housing, the idea is for cows to lie down in a stall such that manure falls into the alley and doesn’t dirty the bedding. However, heifers and cows sometimes lie down backward or in the manure alley instead. So far our results show promise, and visiting McGill University undergraduate Jessica St-Pierre is considering trying this strategy on her family’s dairy farm in Quebec!

Open house JMV 170722

I set up the brushes with extra-stiff (black) and stiff (yellow) bristles for our visitors to feel and compare. The Lely automated rotating mechanical brush is in the background.

Open house 5023 brush lick 170722

One of my favorite friendly cows, 5023, wanted to check out the brushes too…

Open house 5023 brush head 170722

… So we mounted one on the fence for her and her buddies to investigate. Here, 5023 is getting in a good face rub!

Rotating brushes for cows

Ana, a PhD student and veterinarian from Colombia, is currently running a study with a rotating mechanical brush. She is investigating how mange, resulting from mite infestations, affects how much cows want to use the brush. Mites tend to dwell around the tailhead (where the tail meets the body), which is a difficult place for cows to reach and groom themselves. A mechanical brush can help cows relieve itchiness in that area of their body. To evaluate how important a resource – such as a brush – is to animals, we can ask them to pay a price. But the price involves performing a task or overcoming an obstacle instead of paying money. For her experiment, Ana has trained cows to push a gate to get access to the brush, and she can increase the “price” by adjusting the force needed for cows to open the gate.

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Cow 4095 demonstrates how the mechanical brush can help her groom hard-to-reach areas such as her back

Check out this video clip I put together of some of the cows using the rotating brush in a variety of ways during the open house:

  • on the tailhead, where mange tends to occur
  • under the tail (a couple visitors joked it was like cow TP!)
  • on the head (doubling as a punching bag!)

Clear as mud?

Moisture can create muddy surfaces on pasture or in housing systems such as drylots and bedded packs. Dairy cattle show signs of increased stress in rainy and windy conditions, but previous research had not separated the effects of inclement weather from muddy ground conditions.

We housed pregnant cows and heifers in dirt-floored enclosures to evaluate the effects of muddy ground conditions on their lying behavior, dirtiness, and physiological responses.

Our results were hardly clear as mud! Rather, our cattle made it clear that they were reluctant to lie down on muddy surfaces. In fact, they often chose to lie down on the concrete floor in front of the feed trough instead, even though past research has shown that cows typically avoid lying on concrete. Previous studies have also found that it is important for cows to spend over half of their day lying down, but when the ground was muddier, our cattle spent more time standing up.

Our results show that – even in the absence of rain or wind – muddy ground surfaces have negative effects on the comfort and welfare of dairy cattle.

For our other findings, check out our paper in Journal of Dairy Science or listen to my 4-minute narrated slideshow explaining our study:

Jennifer M. Chen, Carolyn L. Stull, David N. Ledgerwood, and Cassandra B. Tucker. 2017. Muddy conditions reduce hygiene and lying time in dairy cattle and increase time spent on concrete. Journal of Dairy Science 100:2090-21036doi:10.3168/jds.2016-11972.

ADSA Pittsburgh

2017 ADSA poster

Last week I attended the 2017 American Dairy Science Association meeting in Pittsburgh, PA. I presented a poster on our project “Sampling strategies for dairy cow welfare assessments“, which is nearly ready to submit for publication.

During her M.Sc., Julia Trieb visited from Austria and collected about two dozen animal-based measures on 10 California drylot and freestall dairy operations. She restrained the cows in headlocks at the feed bunk to assess measures such as discharge and skin injuries, and released the cows one-by-one to watch them walk in order to score lameness.

Scoring all cows for so many measures can be time consuming, so we wanted to evaluate the accuracy of assessing a subsample of the pen.

We selected proportions ranging from 1/10 to 3/4 of the high-producing pen, and found that in our sample, we had to score at least 2/3 of the pen for all measures to be considered accurate.

We also compared different methods for selecting cows, and we found that choosing cows based on their position while locked at the feed bunk (i.e., pick 2, skip 1, pick 2, skip 1…) performed about the same as selecting cows randomly. Selecting cows based on their lockup position may be a more straightforward approach on farms that have headlocks.



UBC at the Western Canadian Dairy Seminar

I recently attended the 35th annual Western Canadian Dairy Seminar in Red Deer, Alberta. It was a big year, with over 900 attendees! I had a great time meeting producers and discussing their concerns about and ideas for improving cow comfort. I also chatted with some folks about thinking outside the box (but inside the litter box?) regarding cattle waste management. (Not to mention experiencing some “real” Canadian winter…!)

DFC 20170309

Here I am with UBC PhD students Heather Neave, Hanna Eriksson (both Animal Welfare Program), and Tracy Burnett (Reproduction Program) in the Dairy Farmers of Canada booth on International Women’s Day! (March 8, 2017)

About a dozen of us from UBC’s Animal Welfare and Reproduction programs represented the UBC Dairy Research & Education Centre. We created posters highlighting the take-home messages we’ve learned across some of our recent studies.

The topics presented by the Animal Welfare Program were:

  1. Colostrum management for calves
  2. Benefits of group housing for calves
  3. Transition cow management
  4. Outdoor access for lactating cows
WCDS booth dairy centre 2017

The UBC booth – click on the links above to see the pdfs of our posters!

Anne-Marieke Smid and I created the poster on outdoor access for lactating cows, which is based on her PhD work that is currently in progress. I recently posted some great photos from her study here.

The cows at UBC are normally housed indoors in a freestall barn with deep-bedded sand. Previous research has shown this to be the favorite indoor bedding type for cows. When Anne-Marieke gave the cows access to pasture, they spent 90% of the night outside.

However, giving cows access to pasture is not always feasible. Anne-Marieke also offered them access to outdoor packs with either sand or bark mulch covering the ground. So far, she has found that they spend about half of the night outdoors. She is now looking into how the amount of time they spend outside is influenced by weather conditions. Check out our poster for photos and graphs, or read Anne-Marieke’s interview with The Western Producer.

Who let the cows out?

My colleague Anne-Marieke Smid, a Ph.D. student in the UBC Animal Welfare Program, is nearing the end of a study she’s conducting. She is housing lactating cows in groups of 12 at a time. They have deep sand-bedded freestalls indoors and get access to an outdoor area.

In one of her previous studies, she gave cows access to a pasture overnight, but Anne-Marieke is also interested in understanding how cows respond to other types of outdoor options besides grass. In another study, she offered them an outdoor sand pack overnight. Now Anne-Marieke is providing cows with 24-hour access to a bark mulch pack, and she collected data in both summer and winter.

We’ve been working on a poster about these studies to present at the Western Canadian Dairy Seminar next month (March 7-10) in Red Deer, Alberta. If you’re going to be there, please come by the UBC Dairy Education & Research Centre booth to meet us and we’ll tell you all about it! (*Update: see here for a recap of the meeting!)

This morning, it was time for a new group of cows to go outdoors for the first time and get used to the bark mulch pack. Last week we got a great deal of snow and there was still quite a bit on the ground, but today was a warmer day. Check out the photos below to see what the cows thought!


Anne-Marieke released pairs of cows at a time from the barn


They started sniffing around to check out the snow…


…and the bark mulch pack


They had to figure out that there was an electric fence around the pack


As more cows came out…


…things started getting frisky!


Some of the cows started bucking…


…and kicking!…


…and even rearing! WOOOHOOO!!!! (my luckiest photo of the day)


Here are all 12 girls outside on the bark mulch pack. Don’t they look like kids at recess?

Dairy open houses in British Columbia

Last week was the 49th annual B.C. Dairy Expo, which included a Farm Tour. Nine local dairies in the Fraser Valley held open houses. This pdf brochure shows the list of farms and their features.

I managed to visit the 4 dairies in Abbotsford and the 2 in Deroche. What the participating farms had in common was a lot of investment in new infrastructure and technology. Some of the farms had the following:

Robotic milkers: a stall that a cow enters voluntarily at a time of her chosing to get milked. The teat cups are attached by a machine using lasers for guidance, which was very cool to watch! This system is in contrast to traditional milking which happens on a schedule (typically 2-3 times a day) and is done with human labor to attach the milking machine.

Rotary parlors: a carousel that a cow walks onto to get milked, and may or may not use robotic teat cup attachment. A rotary allows for improved efficiencies during milking such as reduced walking for both cows and workers. Cows enter individually and exit when each is done being milked, instead of as a group, where the slowest-milking cow determines how long it takes to finish each set.


This farm had an observation deck and video monitoring of their new rotary parlor. Another local dairy on the tour was playing Haydn’s trumpet concerto in their rotary parlor!

– Automatic feed pushers and self-driving feeders: These robots look kind of like big Roomba vacuums! The self-driving feeders like the Lely Vector both deliver fresh feed and also push the feed closer to the cows so they can reach it. The automatic feed pushers like the Lely Juno just do the latter. We even saw one robot deftly navigate around the table where coffee and donuts were being served.


On this farm, the heifers sniffed and licked the feed delivering robot as it went by!

Many of the farms had entirely new barns or new freestalls for the cows. Deep sand was the most popular bedding type, and this was great to see because research has shown that cows prefer lying down on this material.

We did observe a few potential animal welfare issues on some farms, such as cows lying in the concrete alley instead of in their stalls, heifers standing in stagnant water, and a few docked tails.

However, we also saw some management decisions that are promising for improving animal welfare. Most farms had fans to reduce heat stress in the summer, and many also offered environmental enrichment for the heifers and adult cows in the form of automatic rotating brushes.


An automatic feed pusher and a cow using a rotating grooming brush in the background

Another welfare-friendly strategy on some farms was to use group housing for their pre-weaned calves. Individual housing is more common due to the idea that this promotes biosecurity and allows for easier monitoring of calf performance. However, automatic calf feeding machines now provide the ability to record how much individual calves eat and drink. In addition, research by the UBC Animal Welfare Program has shown that group housing improves both cognitive performance and feed intake in calves.

Interestingly, one dairy provided hay for its pre-weaned calves. This practice is uncommon based on the idea that consuming forage displaces grain-based calf starter, resulting in reduced energy intake and growth. However, research at UBC suggests that eating forage improves rumen development in calves. One research topic I may explore during my postdoc at UBC will be to look at how important access to roughage is from a behavioral perspective, similar to the work I did with beef heifers at UC Davis.


This farm provided hay in addition to milk, water, and grain-based calf starter for its pre-weaned calves. Although they were housed individually, the calves had barn cats as social companions!

In addition, the avoidance distance was in general very low on the farms I visited. This measure refers to how close cows will let people get to them before they move away. It can be an indication of how comfortable they are with humans and may indirectly reflect how they have been treated.


These cows had short avoidance distances – they kept feeding instead of backing away when I got close to them. In the background, you can see fans, DeLaval rotating brushes, and a person driving a Bobcat to push the feed.

All in all, it was a very interesting and informative day, and I was really grateful to the B.C. producers for opening up their farms to visitors!

New year, new job

Greetings from snowy British Columbia!

I’m thrilled to have joined the renowned Animal Welfare Program at the University of British Columbia as a postdoctoral fellow.

I’m based at the UBC Dairy Education and Research Centre in Agassiz. The above photo shows a view of the facilities and Mt. Cheam after last week’s fresh snow fall. It’s quite a change from central California, but I’m so excited to be here.

The dairy milks about 260 cows, and it’s been fun to get to know them, the farmers, and the students doing research onsite. I’m currently in the brainstorming phase, but I look forward to running my own projects here very soon!




California Cattlemen’s Association Centennial Celebration

CCA Dean Helene Dillard 161202 croppedLast week I attended the 100th Annual Convention of the California Cattlemen’s Association & California Cattlewomen, which was held in Sparks, NV.

I presented a poster about our recent study on feeding motivation in feedlot cattle, and Helene Dillard, the dean of the College of Agricultural and Environmental Sciences at UC Davis, stopped by to check it out.

Here’s a summary of what we examined in this study:

In the finishing stage of beef production, feedlot cattle are commonly fed high-concentrate diets to improve growth and production efficiency. However, this practice is associated with animal welfare concerns, as it can impair physical function in the form of acidosis, or low rumen pH. In addition, it is unknown whether cattle, ruminants that have evolved to feed on roughage, have an intrinsic motivation to consume dietary fiber.

Our objective was to evaluate how much feedlot cattle want to obtain a source of dietary fiber when they are fed a high-concentrate finishing diet. To quantify their degree of motivation, we asked cattle to push a weighted gate with their heads to gain access to dietary fiber. We found that cattle fed a high-concentrate diet pushed the gate to access hay immediately after it was presented, more than an hour sooner than those fed a high-fiber diet. This pattern remained unchanged even when the weight on the gate, and thus the challenge of pushing it, increased.

This demonstrated that cattle fed a high-concentrate diet were motivated to gain access to dietary fiber. In future studies, we plan to investigate whether this motivation is explained by changes in the rumen environment, a need to perform chewing and ruminating behavior, or both.

It was an exciting couple of days meeting beef producers, joining in the centennial celebration, and attending a Cattlemen’s College workshop led by Darrh Bullock from the University of Kentucky. He talked about beef breeding, and you can check out some free educational resources here.