...From the pages of Agricultural Research magazine
|The feds pull up in a surveillance
van and park in a nearby alley. Walking carefully in the dark, they place a
special, remote-controlled camera on a 12-foot-tall tripod. From inside the
van, they use a joystick to turn the camera almost 360 degrees, to zoom in and
pick out individuals in the nighttime crowd. They can also look out the
trailer's windows with the latest generation of night-vision scopesor use
them to spy from the security of a platform on top of the van. They still find
it difficult to pick out a dozen or so suspects from the hundreds in the crowd.
They've tried marking them with the same tape and paint used to mark vehicles of friendly forces in combat. The coded symbols made with the tape or paint are then visible under infrared lights.
But the tape doesn't stick to their bodies, and the paint raised safety concerns over the long run.
Atop a mobile animal-surveillance
|These feds aren't in a militaryor even policeoperation. Instead, they're a U.S. Department of Agriculture team of farm animal behaviorists in action. Their "suspects" are individual cattle in a herd they are observing at a commercial feedlot in the Texas Panhandlethe feedlot capital of America, if not the world. Julie Morrow-Tesch has set up livestock behavior studies units at West Lafayette, Indiana, and at Lubbock, Texas, for USDA's Agricultural Research Service (ARS). She is one of a handful of farm animal behaviorists in the country. Another is Don Lay, formerly at Iowa State University and recently hired to lead the West Lafayette unit. Soon his unit will be hiring a swine behaviorist. These hires are part of ARS' research drive to find objective ways of measuring stress in farm animals to improve animal handling practices.|
|"The stresses we're talking about can cause real problemsslower growth, illness, injury, and sometimes death to livestock," Morrow-Tesch says. "Besides the humane concerns, we're talking about stresses that cost real money in reduced production. Just as an indicator of the costs involved, increasing survival by just one piglet per litter can provide the livestock industry an extra $100 million or more in sales. And that doesn't include the savings that can come from better quality meat, faster growth, bigger animals, and less use of medicine and veterinary services." Morrow-Tesch and colleagues bring the mobile lab to the large outdoor feedlots for a 24-hour surveillance once each season, year-round. They use the remote camera or sit on the van's roof platform to observe, using binoculars by day and night-vision scopes by night. They check on the behavior of individual cattle every 15 minutes.|
|There are 200 to 250 head of cattle in each 100-by-100-foot pen. Morrow-Tesch can survey several of the side-by-side pens from the mobile lab. The mobile lab keeps her out of sight of the cattle, and the cattle are used to the van being present. The night-vision scopes are used to avoid the need for bright lights that could distract cattle. All the surveillance is designed to be discreet, so cattle can be observed in a normal setting. The feedlot research has already shown that feeding the animals at dusk instead of mainly at dawn significantly cuts down on animal roughhousing and attendant injuries. "We noticed that switching the main meal from morning to just before sunset cut the number of aggressive incidents by almost half," Morrow-Tesch says.|
|These observations convinced her that animals were less restless when their main meal was at night rather than at dawn. It seemed that if they couldn't indulge their instinctive desire to munch at dusk, they looked for other activities. These include mounting, or bulling, and just plain bullyingpushing and shoving. "When we recorded the frequency and duration of this type of behavior, we saw a definite change for the better when they were fed at dusk," Morrow-Tesch says. For the study, Morrow-Tesch and her colleaguesARS technicians and Texas Tech studentsrecorded the following behaviors: feeding, drinking, standing, lying, walking, aggression, bulling, and socializing. They observed a total of 5,565 steers in 31 pens.|
On an icy cold day at the Sustainable
|Injuries from the bulling behavior cost feedlots an average of $70 a head. And that figure doesn't include injuries from other aggressive behaviors or the dust kicked up by the extra activity. "As a measure of stress, behavior is critical to our studies in commercial feedlots," Morrow-Tesch explains. "We can't go to these feedlots and take weekly blood samples to look for stress indicators as we do in the lab. Here we have to use noninvasive detection methods, so observing behavior is the best way we can do that. The characterization of the behavior of feedlot cattle in West Texas has never been done before. This is applied research in a commercial setting. It requires a high level of cooperation between the feedlot owners and operators and researchers. Plus we had to develop the techniques for observing the undisturbed behavior of commercial cattle over a 24-hour period."|
| It is only through such voluntary
cooperation that Morrow-Tesch can analyze a feedlot's production records for
data that will put her findings in the context of practical economics.
"For example, our next task in this study is to analyze industry data and
see if it makes economic sense to add a new shift of workers to feed the cattle
in the evening," she says.
Another of her feedlot studies showed the value of shading cattle over misting
them to cool them on hot days. The study was done with 80 feedlot heifers. The
shaded heifers reached their market weight 20 days earlier than unshaded
heifers and were about 60 pounds heavier at slaughter. The results need to be
analyzed to see if it would be practical to build shade roofs to reduce
production losses due to heat stress.
The Long Road to Market
Another concern of Morrow-Tesch's is the growing practice of shipping week-old
piglets to other production facilities.
"These piglets are traveling great distanceslike from North Carolina
to the Midwestand we're wondering if this has any harmful effects on
them," says Morrow-Tesch.
To find out, last spring she began shipping piglets in trucks specially
equipped foryou guessed itsurveillance.
"We shipped piglets from Lubbock to the Lamar, Colorado, area and on the
return trip brought back adult hogs ready for slaughter," she says.
"It's more difficult to measure behavior when transporting fully grown
pigs than piglets because they're taller. The camera is closer to them, so we
had to change to a wide-angle lens to view them all. Plus, when they stand on
each other they can bite the camera if we don't have it up high enough. It took
us many practice runs to get everything right," she says. "We also
had to keep the cameras from rattling around in the trucks."
Morrow-Tesch has the trucks equipped with sensors to record air temperature and
humidity in the area where the pigs ride. She and her colleagues take blood
samples before and after each trip, looking for biochemical changes in levels
of cortisol and other hormones or chemicals that may be indicators of the
animals' stress levels. "We hope to eventually have a sensor that records
road vibrations, too," she adds.
So far the researchers have clues suggesting that it may not be the long truck
ride and road vibrations stressing piglets as much as the attendant isolation
during the trip. They found this in a study of piglets from eight litters. They
isolated male and female piglets aged 7 to 10 days old in a holding area for
the same amount of time as piglets that were transported. The isolated piglets
lost more weight than the transported piglets, and their glucose levels were
"This is one of many examples in which it seems that psychological
stresses are worse than such physical stresses as mildly higher or cooler
temperatures or road vibrations," Morrow-Tesch says.
"We are building on knowledge of stress developed since the 1930s. One
example is the fight-or-flight response, where stress can cause higher blood
levels of adrenalin that can be damaging," she says.
In their studies to date, the scientists have verified and added to knowledge
about swine immune responses to stress.
"We need to develop an up-to-date stress model for livestock," she
says, "one that uses the new knowledge that farm animal behaviorists are
developing. This model will save a lot of wear and tear on livestock handlers,
as well as livestock. And that translates into higher efficiency and profits,
healthier and happier animals, and possibly a safer food supply for
In the future, Morrow-Tesch says she and her colleagues will study the effects
of stress on behavior, physiology, microbiology, and production. In one study
soon to be under way, Morrow-Tesch and colleagues will artificially manipulate
stress hormones produced in the brains of pigs, as a model of stress.
"We'll then be able to identify how stress affects behavior, immune
response, and pathogen levels in these animals."By
Agricultural Research Service Information Staff.
This research is part of Animal Well-Being and Stress Control Systems, an
ARS National Program (#105) described on the World Wide Web at
Julie Morrow-Tesch is in the USDA-ARS Livestock Issues Research Unit, Texas Tech University, 123B Animal Science Bldg., Lubbock, TX 79409-2141; phone (806) 742-2826, fax (806) 742-2335.
"High-Tech Spyingon Livestock" was published in the June 2001 issue of Agricultural Research magazine.