TY - JOUR
T1 - Prepartum concentrate supplementation of a diet based on medium-quality grass silage: Effects on performance, health, fertility, metabolic function, and immune function of low body condition score cows
AU - Little, M. W.
AU - O'Connell, N. E.
AU - Welsh, M. D.
AU - Barley, J.
AU - Meade, K. G.
AU - Ferris, C. P.
PY - 2016/9
Y1 - 2016/9
N2 - When cows with a “higher” body condition score
(BCS) are oversupplied with energy during the dry period,
postpartum energy balance is normally reduced,
which can have a detrimental effect on immune competence
and increase the infectious disease risk. However,
within grassland-based systems higher yielding cows
frequently have a low BCS at drying off. The effects on
performance, health, and metabolic and immune functions
of providing additional energy to cows with low
BCS during the dry period is less certain. To address
this uncertainty, 53 multiparous Holstein-Friesian cows
(mean BCS of 2.5; 1–5 scale) were allocated to 1 of 2
treatments at dry-off: silage only or silage plus concentrates.
Cows on the silage-only treatment were offered
ad libitum access to medium-quality grass silage. Cows
on the silage-plus-concentrate treatment were offered
ad libitum access to a mixed ration comprising the
same grass silage plus concentrates [in a 75:25 dry matter
(DM) ratio], which provided a mean concentrate
DM intake of 3.0 kg/cow per day. Postpartum, cows
were offered a common mixed ration comprising grass
silage and concentrates (in a 40:60 DM ratio) for a
70-d period. Offering concentrates during the dry period
increased DM intake, tended to increase energy
balance, and increased body weight (BW) and BCS
gain prepartum. Offering concentrates during the dry
period increased BW and BCS loss postpartum and
tended to increase milk fat percentage and serum
nonesterified fatty acid concentration, but it did not
affect postpartum DM intake, energy balance, and milk
yield. Although the percentage of phagocytosis-positive
neutrophils did not differ, neutrophils from cows on the
silage-plus-concentrate treatment had higher phagocytic fluorescence intensity at 1 and 2 wk postpartum and
higher phagocytic index at 1 wk postpartum. Serum
haptoglobin concentrations and IFN-γ production by
pokeweed mitogen stimulated whole blood culture were
unaffected by treatment, although haptoglobin concentrations
increased and IFN-γ production decreased
peripartum. Offering concentrates during the dry period
increased the incidence of lameness postpartum,
although other health and fertility parameters were
unaffected. In conclusion, supplementing low BCS cows
with concentrates during the dry period had no effect
on performance and fertility and resulted in a higher
neutrophil phagocytic index at 1 wk postpartum and
an increased incidence of lameness compared with offering
cows a grass silage–only diet prepartum.
AB - When cows with a “higher” body condition score
(BCS) are oversupplied with energy during the dry period,
postpartum energy balance is normally reduced,
which can have a detrimental effect on immune competence
and increase the infectious disease risk. However,
within grassland-based systems higher yielding cows
frequently have a low BCS at drying off. The effects on
performance, health, and metabolic and immune functions
of providing additional energy to cows with low
BCS during the dry period is less certain. To address
this uncertainty, 53 multiparous Holstein-Friesian cows
(mean BCS of 2.5; 1–5 scale) were allocated to 1 of 2
treatments at dry-off: silage only or silage plus concentrates.
Cows on the silage-only treatment were offered
ad libitum access to medium-quality grass silage. Cows
on the silage-plus-concentrate treatment were offered
ad libitum access to a mixed ration comprising the
same grass silage plus concentrates [in a 75:25 dry matter
(DM) ratio], which provided a mean concentrate
DM intake of 3.0 kg/cow per day. Postpartum, cows
were offered a common mixed ration comprising grass
silage and concentrates (in a 40:60 DM ratio) for a
70-d period. Offering concentrates during the dry period
increased DM intake, tended to increase energy
balance, and increased body weight (BW) and BCS
gain prepartum. Offering concentrates during the dry
period increased BW and BCS loss postpartum and
tended to increase milk fat percentage and serum
nonesterified fatty acid concentration, but it did not
affect postpartum DM intake, energy balance, and milk
yield. Although the percentage of phagocytosis-positive
neutrophils did not differ, neutrophils from cows on the
silage-plus-concentrate treatment had higher phagocytic fluorescence intensity at 1 and 2 wk postpartum and
higher phagocytic index at 1 wk postpartum. Serum
haptoglobin concentrations and IFN-γ production by
pokeweed mitogen stimulated whole blood culture were
unaffected by treatment, although haptoglobin concentrations
increased and IFN-γ production decreased
peripartum. Offering concentrates during the dry period
increased the incidence of lameness postpartum,
although other health and fertility parameters were
unaffected. In conclusion, supplementing low BCS cows
with concentrates during the dry period had no effect
on performance and fertility and resulted in a higher
neutrophil phagocytic index at 1 wk postpartum and
an increased incidence of lameness compared with offering
cows a grass silage–only diet prepartum.
U2 - 10.3168/jds.2016-11071
DO - 10.3168/jds.2016-11071
M3 - Article
SN - 0022-0302
VL - 99
SP - 7102
EP - 7122
JO - Journal of Dairy Science
JF - Journal of Dairy Science
IS - 9
ER -