Is group housing a viable option for performance horses? Some trainers think not, believing group housing delays recovery and impairs performance.
Swedish researchers Malin Connysson, Marie Rhodin and Anna Jansson set out to discover if this is true, carrying out an experiment involving eight adult Standardbred trotters.
Their research, reported in the journal Animals, examined the effects of two housing systems — free-range and box stalls — on recovery of energy balance after competition-like exercise in the horses.
The Standardbreds, all geldings and with an average age of 11, were split into two groups. One group spent 21 days in group housing while the other four spent 21 days in individual stalls. After a three-down washout period, they swapped housing arrangements.
The individual stalls measured 3 meters by 3 meters and had wood shavings on the floor.
The group housing saw the four horses kept together in a paved area measuring 3200 square meters with a shelter with rubber matting and automatic feeding stations.
Forage, in the form of haylage, was readily available under both housing scenarios.
The horses each performed two similar race-like exercise tests after seven days and 14 days in each housing system.
Forage intake was recorded during the last 6–7 days in each period. Blood samples were collected before, during, and 44 hours after each exercise test for analysis.
Voluntary forage intake (measured in groups of four) was higher in the group-housed horses than those who were boxed.
Housing did not affect exercise heart rate, plasma lactate, plasma urea, or total plasma protein concentration, the researchers reported.
However, plasma non-esterified fatty acids were found to be lower after 20 to 44 hours of recovery than before in the group-housed horses when compared to those in individual stalls.
This indicated quick and efficient recovery of energy balance by horses in this housing system, they said — an indication also supported by the higher daily feed consumption observed in the free-range housing system.
“The results showed that a free-range housing system did not delay recovery in Standardbred trotters, and in fact had positive effects on appetite and recovery of energy balance,” the trio reported.
“Thus the free-range housing system hastened recovery in Standardbred trotters, contradicting anecdotal claims that it delays recovery.”
The authors noted that low body condition scores and periods of low appetite were sometimes seen in horses during periods of intense training and racing.
“Our results indicate that a group housing system might counteract these problems,” they said.
“Our findings indicate that physical environment is important for feed intake in horses.”
Interestingly, there was no significant difference in heart rate between the housing treatments during short-term recovery, indicating that energy expenditure was similar in this period.
They had expected that heart rate would have been higher for group-housed horses compared to those in box housing due to more physical activity.
Connysson is with the Wången National Center for Education in Trotting; Rhodin and Jansson are with the Swedish University of Agricultural Sciences.
Effects of Horse Housing System on Energy Balance during Post-Exercise Recovery
Malin Connysson, Marie Rhodin and Anna Jansson.
Animals 2019, 9, 976; doi:10.3390/ani9110976