Abstract :
The aim of this experiment was to investigate the effect of increasing the number of ewes
per nipple drinker on water intake, feed intake and drinking behaviour of ewes. A group of
30 1¾ year old, pregnant ewes of the Norwegian Dala breed were exposed to three treatments,
each treatment lasting one week: 7.5 ewes per nipple drinker (N7.5: four nipple
drinkers), 15 ewes per nipple drinker (N15: two nipple drinkers) and 30 ewes peer nipple
drinker (N30: one nipple drinker). The experiment was performed both in January (week
4–6, replicate 1) and replicated in April (week 13–15, replicate 2). The ewes were kept in
insulated building and had free access to good quality hay. Water metres were connected
to the pipeline for water supply and water wastage was collected and weighed. In addition,
the daily intake of hay was recorded and the ewes were video recorded the three last
days of each experimental period. Total drinking time per individual was calculated from
observations of drinking behaviour from the video, as were also incidents of queuing and
displacements. Both water and feed intake was higher in replicate 2 than in replicate 1.
Increasing the number of individuals per nipple drinker had no effect on water intake in
replicate 1, whereas in replicate 2 the water intake was (mean
±
SE) 3.5
±
0.3; 4.2
±
0.1 and
4.9
±
0.1 l/ewe and day in the treatments N7.5, N15 and N30, respectively (P < 0.05). Regardless
of replicate, the time spent drinking increased significantly when number of ewes per
nipple drinker increased. Queuing was not affected by increasing the number of ewes per
nipple drinker. In replicate 1 the number of displacements increased significantly when
the number of individuals per nipple drinker increased (N7.5 = 7.6
±
1.7; N15 = 15.0
±
4.2
and N30 = 36.7
±
5.2; P < 0.05) and the same trend could be seen in replicate 2, although not
significant. In conclusion, one nipple drinker with an acceptable flow rate can serve up to
30 ewes without negatively affecting water and feed intake
