Grazing is considered a normal behavior for dairy
cattle, although they may not be able to meet their
nutritional requirements from grazing alone, and so to
sustain higher yields requires access to a total mixed ration
(TMR). The study aim was to provide dairy cows
with access to TMR indoors and on pasture to establish
influence on behavior and preference for each location.
The study took place from August to November, 2009,
using 36 late-lactation Holstein-Friesian dairy cows.
The cows were allocated to 1 of 3 26-d study periods (n
= 12 × 3). Within each period the cows were further
divided into a control (n = 6) or treatment (n = 6)
group using a crossover design, where the cows were
changed between the control and treatment group after
13 d. Treatment cows had access to TMR indoors and
on pasture, whereas control cows only had access to
TMR indoors. Following a.m. and p.m. milkings the
cows were taken to a point equidistant between indoors
and pasture and given the choice of going to pasture
(1.5 ha) or to a freestall barn. Between milkings the
cows had free access between the locations. Initial
choice was recorded and a video camera was used to
record time spent in each location. Behavior observations
were recorded to establish how the cows spent
their time during the day. To determine what factors
influenced preference, weather conditions, milk yield,
body condition score, and lameness were recorded. Initially,
the cows chose indoors following milking (96.4 ±
0.80%). Overall, the cows expressed a partial preference
for pasture (71.1 ± 1.82%), which was different from
100, 50, and 0%. Study period influenced preference
with cows spending less time on pasture as the season
progressed (86.7 vs. 68.3 vs. 58.3% for study periods 1,
2, and 3, respectively). Providing the cows with TMR
outdoors did not affect pasture use, but resulted in
an increase in TMR intake of 2.2 ± 0.41 kg of dry
matter/d. The cows spent more time on pasture as the
temperature-humidity index indoors (55.6 ± 0.92) and
outdoors (54.6 ± 0.82) increased, but rainfall and milk
yield did not influence preference. Cows with lameness
score >1.5 spent more time indoors (35.4 ± 4.52 vs.
25.2 ± 2.64% for cows with >1.5 vs. ≤1.5 lameness
score, respectively). In conclusion, the cows expressed a
partial preference for pasture, which was not influenced
by providing TMR on pasture.