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Livestock Production Science 86 (2004) 239–251
Concentrate feeding strategy of dairy cows during transition period
Tuomo Kokkonen*, Alem Tesfa, Mikko Tuori, Liisa Syrjala-Qvist
Department of Animal Science, University of Helsinki, P.O. Box 28, 00014 Helsinki, Finland
Received 17 June 2002; received in revised form 25 June 2003; accepted 2 September 2003
Abstract
Thirty multiparous Friesian cows were used in a 2� 2 factorial design to study the effects of concentrate proportion during
the late dry period and concentrate increase rate after calving, on grass silage-based diets. For 3 weeks before calving,
concentrate proportion in the diet was 20% (L), 40% (M) or 60% (H) of cows’ individual energy requirements. After calving,
the slow (S) concentrate increase groups (LS, MS and HS) received an additional 0.5 kg/day during the first 10 lactation days
and 0.3 kg/day thereafter until 15 kg/day was achieved. In the fast (F) groups (LF, MF and HF), the increase was 2 kg/day for
the first 2 days after parturition, followed by 1 kg/day for the next 2 days and 0.5 kg/day thereafter.
The proportion of concentrate in the prepartum diet had no effect on voluntary silage dry matter intake (DMI) postpartum.
During lactation weeks 1–5, the fast increase of concentrate tended to increase (P < 0.10 or better) milk yield, and an increased
proportion of concentrate in the prepartum diet tended to decrease (P < 0.10 or better) fat content. The average response of ECM
yield during the 8-week experiment to fast increase of concentrate was 1.68 kg per increased kilogram concentrate dry matter. L
groups had higher (P< 0.05) plasma NEFA than the other groups 1 week before calving. Cows in LS had a more negative energy
balance than the cows in other groups and high blood ketone values during first weeks of lactation. A high proportion of
concentrate elevated (P< 0.05) blood insulin prepartum, but did not decrease plasma NEFA 1 week before calving.
D 2003 Elsevier B.V. All rights reserved.
Keywords: Dairy cows; Grass silage; Concentrate; Feed intake; Lipid mobilization
1. Introduction dry period when cows received a low-energy diet.
Lead feeding with increasing concentrates during
the last few weeks before calving has been a common
practice in Europe as well as in North America for
many years (Broster, 1971; Shaver, 1997). The aim of
this practice is to adapt the cow and its rumen function
to the diet to be fed after parturition.
Dirksen et al. (1985) reported that the cross-sec-
tional area of ruminal papillae decreased during the
0301-6226/$ - see front matter D 2003 Elsevier B.V. All rights reserved.
doi:10.1016/j.livprodsci.2003.09.003
* Corresponding author. Tel.: +358-9-191-58561; fax: +358-9-
191-58379.
E-mail address: [email protected] (T. Kokkonen).
When cows were introduced to a high-energy diet 2
weeks prior to parturition, the cross-sectional area of
ruminal papillae started to increase, reaching maximal
size at 6–8 weeks postpartum. Furthermore, Dirksen
et al. (1985) showed that relative volatile fatty acids
(VFA) absorption was enhanced with a high-energy
diet. In contrast, Andersen et al. (1999) found no
macroscopic or histological effects of dry cow con-
centrate feeding on rumen epithelium.
During the immediate prepartum period, cows have
decreased feed intake. The duration and magnitude of
depressed intake varies, but it seems to be more severe
with ad libitum than restricted feeding (Kunz et al.,
Table 1
Chemical composition and nutritional value of feeds
Silage
average
S.D. Concentrate Rape
seed meal
Number of samples 9 2 1
Dry matter (g/kg) 290.9 42.5 875.1 887.4
Ash (g/kg DM) 77.7 11.9 62.0 73.9
Crude protein (g/kg DM) 125.3 18.3 147.1 354.7
Ether extract (g/kg DM) 40.4 6.5 41.4 73.5
Crude fibre (g/kg DM) 289.5 36.7 78.5 132.7
NDF (g/kg DM) 538.3 59.2 220.0 283.6
ADF (g/kg DM) 299.8 32.3 84.0 190.8
Starch (g/kg DM) 498.7 57.0
ME (MJ/kg DM) 9.98 0.65 12.81 11.74
AAT (g/kg DM) 80.6 4.6 101.3 147.2
PBV (g/kg DM) � 6.8 12.0 � 17.7 128.6
Fermentation quality of grass silage: soluble N 519 g/kg N, NH3–N
53 g/kg N, WSC 64 g/kg DM, lactic acid 36.1 g/kg DM, acetic acid
16.0 g/kg DM, butyric acid 1.9 g/kg DM.
S.D. = standard deviation; DM= dry matter; NDF= neutral detergent
fibre; ADF = acid detergent fibre; N = nitrogen; WSC=water-
soluble carbohydrates; ME=metabolizable energy; AAT= amino
acids absorbed from the small intestine; PBV= protein balance
value in the rumen.
T. Kokkonen et al. / Livestock Production Science 86 (2004) 239–251240
1985). In conjunction with feed intake depression,
lipid mobilization from adipose tissue increases. Lead
feeding of concentrates may prevent excessive lipid
mobilization and liver glycogen depletion prior to
parturition via increased blood insulin. This, in turn,
may decrease fatty acid infiltration of the liver and
decrease the incidence of ketosis (Grummer, 1993,
1995). Moreover, adaptation of the rumen and its
microbes to a diet of high-energy density by lead
feeding may decrease the risk of left displaced ab-
omasum and ketosis through reduced risk of acidosis
and enhanced appetite during the first weeks of
lactation (Curtis et al., 1985).
A negative energy balance forces early-lactation
cow to mobilize adipose tissue reserves to reach its
genetic milk yield potential. Increasing the energy
density of the diet can reduce the extent of lipid
mobilization. A diet of inadequate energy density
may force cows with high milk yield potential to
mobilize excessive amounts of lipids, thus increasing
the risk of ketosis. In addition, a low-energy diet can
prevent achievement of milk yield potential. However,
because high concentrate feeding or a rapid increase
of concentrate allowances during early lactation may
lead to disturbances of rumen function, digestive
disorders and reduced dry matter intake (DMI) (Ols-
son et al., 1997; Ingvartsen et al., 2001), the intended
increase of energy intake may be compromised.
Earlier experiments at our institute (Tesfa et al.,
1999) and elsewhere (Boisclair et al., 1986; Grum et
al., 1996; Vandehaar et al., 1999) have shown no
beneficial effects of increased energy level during the
late prepartum period on milk yield or feed intake
postpartum. Therefore, our intention was to study the
energy density of prepartum diet with three different
proportions of concentrate to forage with restricted
energy allowance. In addition, two increase rates of
concentrate postpartum were examined.
We hypothesized that an inadequate concentrate
proportion in the diet during lead feeding would result
in decreased feed intake and milk yield during early
lactation. Secondly, an excessively high or low con-
centrate proportion prepartum together with a rapid
concentrate increase rate postpartum were anticipated
to cause digestive disorders and off-feed problems.
Finally, the high increase rate of concentrate postpar-
tum would presumably lead to increased milk yield
and decreased live weight change.
2. Materials and methods
2.1. Animals and experimental design
Thirty multiparous dairy cows (Finnish Friesian)
were divided into six treatment groups using a ran-
domized complete block design. Blocks of six cows
were formed taking into account the expected calving
date, live weight, milk yield of previous lactation and
previous peak yield. The animals within these blocks
were then allotted to the different treatments.
The experimental period started 3 weeks before
parturition and lasted for 10 weeks after calving.
Before calving, cows were divided into three treat-
ment groups: low (L), medium (M) or high (H)
concentrate feeding. After calving, each of the groups
were further divided into two groups: slow (S) or fast
(F) increase of concentrate ration.
2.2. Feeds and feeding
Chemical composition and nutritional value of
feeds are given in Table 1. The concentrate mixture
of grain and peas consisted of 37% barley, 36% oats,
20% peas, 3% mineral supplement and 4% compound
feed.
T. Kokkonen et al. / Livestock Product
In the 3 weeks before calving, the proportion of
concentrate in the diet was 20%, 40% or 60% of
individual energy requirement in groups L, M and H,
respectively. The rest of the energy requirement was
met with wilted silage. Cows were fed 110% of the
Finnish energy standard (Tuori et al., 1996). Orts were
not collected during the prepartum period. Average
feed and nutrient allowances prepartum are shown in
Table 2.
After calving, the slow increase of concentrate
(groups LS, MS and HS) was 0.5 kg/day during the
first 10 lactation days and 0.3 kg/day thereafter. In
the fast groups (LF, MF and HF), the daily increase
was 2 kg for 2 days after parturition, followed by 1
kg for the next 2 days and 0.5 kg thereafter. The daily
allowance of 15 kg/day was achieved at 37, 18, 31,
14, 23 and 11 days after calving in groups LS, LF,
MS, MF, HS and HF, respectively. The concentrate
was fed five times a day. Due to the low crude
protein (CP) content of silage, 0.8 kg/day rape seed
meal (RSM) was given as a protein supplement.
Wilted grass silage was fed ad libitum, allowing 5–
10% orts daily. The silage was distributed with an
automated feeding car twice a day. Orts from con-
centrate and silage were collected separately and
weighed daily.
Table 2
Prepartum average feed and nutrient allowances, live weight and
body condition score
LS LF MS MF HS HF
Silage
(kg DM/day)
9.2 9.0 7.1 6.4 5.3 5.2
Concentrate
(kg DM/day)
1.6 1.6 2.9 3.2 4.5 4.7
Total
(kg DM/day)
10.8 10.6 10.0 9.6 9.8 9.9
ME (MJ/day) 109 106 106 104 108 110
Crude protein
(g/day)
1305 1269 1243 1252 1210 1269
Live weight,
� 3 weeks
(kg)
691 681 675 680 682 710
Body condition
score,
� 3 weeks
3.42 3.30 3.32 3.36 3.24 3.56
L= low concentrate prepartum; M=medium concentrate prepartum;
H = high-concentrate prepartum; S = slow increase rate of concen-
trate postpartum; F = fast increase rate of concentrate postpartum.
Abbreviations as in Table 1.
2.3. Sampling and chemical analysis
Feeds were sampled weekly. Concentrate samples
were pooled to form a 2-month sample. Silage sam-
ples from the same silo were pooled, although not for
a period longer than 1 month. Samples were analysed
as described by Kokkonen et al. (2002).
The cows were kept in stalls and milked twice
daily. Milk yield was recorded for every milking.
Milk samples were taken on four consecutive milk-
ings at 1, 2, 4, 6, 8 and 10 weeks after parturition.
Fat, protein, urea and acetone contents were analysed
(Kokkonen et al., 2000a,b). Live weights were mea-
sured on 2 consecutive days 3 weeks before the
expected calving date, at the time of calving and at
1, 2, 4, 6, 8 and 10 weeks after calving. Condition
scoring (scale 1–5, Edmonson et al., 1989) was done
by the same person throughout the experiment in
conjunction with weighing.
Blood samples from the jugular vein were extracted
at 3 weeks and at 1 week before the expected calving
day, and at 1, 4 and 8 weeks after calving, before
afternoon feeding at 1300 h (Kokkonen et al., 2000a).
h-Hydroxybutyrate (BHB), acetoacetate, glucose, non-esterified fatty acids (NEFA), insulin and glucagon
were determined with the methods described by Kok-
konen et al. (2000a). In addition, urea (Gutman and
Bergmeyer, 1974) and triglycerides (Wahlefeld, 1974)
were determined from plasma.
2.4. Calculations and statistical methods
Digestibility values taken from feed tables (Tuori et
al., 1996) were used for calculating feeding values. A
regression curve was fitted to the live weight data of
each animal to evaluate live weight changes. Energy-
corrected milk yield was calculated according to
Sjaunja et al. (1991).
Data for milk yield, composition, feed intake, live
weight, ME balance and body condition scoring were
separated into two periods: period 1 = 1–35 days and
period 2 = 36–70 days after parturition. Daily obser-
vations of milk yield and feed intake were reduced to
weekly averages. Repeated measures were analysed
using the PROC MIXED procedure of SAS (version
6.12). The statistical model included main plot factors
of treatment and block, subplot factors of time and
interactions between time and treatment and time and
ion Science 86 (2004) 239–251 241
T. Kokkonen et al. / Livestock Production Science 86 (2004) 239–251242
block. Time corresponds to lactation week for milk
yield, feed and nutrient intakes, live weight data and
ME balance and to sampling/scoring day for milk
composition and body condition scoring. For each
analysed variable, cow nested within treatment was
subjected to three covariance structures: compound
symmetry, unstructured and autoregressive order 1.
For analyses of milk composition and body condition
score data covariance structure spatial power law was
used instead of autoregressive order 1. The covariance
structure that resulted in the largest Schwarz Bayesian
criterion was chosen (Littell et al., 1996).
Energy and nutrient utilization, live weight and
body condition score changes (average of each period)
and blood sample data within the sampling time were
analysed with the PROC MIXED procedure with a
model including the fixed effect of treatment and the
random effect of block.
Milk acetone, blood urea, NEFA, ketone and in-
sulin data were not normally distributed. Therefore,
these data were analysed with Friedman’s two-way
nonparametric analysis of variance using SAS.
Table 3
Feed intake and milk yield, days 1–35
LS LF MS M
Silage DM intake (kg/day) 8.1 7.5 8.4
Silage DM intake (% LW) 1.26 1.22 1.37
Concentrate DM intake (kg/day)a,b 8.7 11.7 10.1
Total DM intake (kg/day)a 16.8 19.2 18.5
ME (MJ/day)a,b 191 222 212
Crude protein (g/day)a,b 2398 2685 2657 2
AAT (g/day)a,b 1554 1789 1719 1
PBV (g/day) � 138 � 237 � 151 �Starch (kg/day)a,b 4.0 5.5 4.7
NDF (kg/day)a 6.4 6.8 6.9
Milk (kg/day)a 32.7 32.8 31.8
ECM (kg/day)a 33.6 33.6 31.8
Fat (g/kg) 43.3 42.3 39.8
Protein (g/kg)a 34.1 34.3 33.2
Urea (mg/100 ml)a 20.9 18.3 18.8
Acetone + 1 week (mmol/l) 0.79 0.23 0.34
Acetone + 4 weeks (mmol/l) 0.12 0.11 0.08
Fat (g/day)a 1371 1343 1259 1
Protein (g/day)a,b 1080 1096 1021 1
Abbreviations as in Table 1; S.E.M. = standard error of mean; LW= live w
jP < 0.10; *P< 0.05; **P < 0.01; ***P < 0.001.
C1 =L vs. (M+H), C2 =M vs. H, C3 = S vs. F, C4 =C1�C3 and C5=Ca Significant ( P< 0.05) time effect.b Significant ( P < 0.05) interaction treatment� time.
In all the above-mentioned statistical analyses,
the effect of feeding was further separated into
orthogonal, linear contrasts: C1 = L vs. (M +H),
C2 =M vs. H, C3 = S vs. F, C4 = C1�C3 and
C5 =C2�C3. Effects were considered to be signif-
icantly different at P < 0.05, and tendencies were
declared at P < 0.10.
3. Results
3.1. Feed intake and milk yield
During period 1, total DMI was higher in groups
with the highest concentrate ration at the time of
calving and a rapid increase of concentrate after
calving (Table 3). As a result of different starting
values at parturition and increase rates of concentrate
(Fig. 1), significant time� treatment interactions
(P < 0.05) were found between time and intakes of
concentrate, metabolizable energy (ME), CP and ami-
no acids absorbed from the small intestine (AAT). In
F HS HF S.E.M. C1 C2 C3 C4 C5
7.8 8.2 8.9 0.53
1.22 1.32 1.34 0.081
12.4 12.1 12.9 0.22 *** *** *** ** **
20.1 20.3 21.8 0.60 *** ** **
236 236 253 6.4 *** ** ***
943 2914 3047 80.8 *** * **
907 1905 2028 50.4 *** ** ***
168 � 198 � 266 34.5 * *
5.9 5.5 6.2 0.06 *** *** *** *** **
6.9 7.0 7.6 0.29 *
36.4 34.4 36.4 1.39 j36.9 32.6 36.0 1.50 *
40.6 36.3 37.0 1.80 * j34.1 34.0 36.3 0.82 j j18.0 19.5 16.2 1.72
0.25 0.14 0.16 0.138 j j0.12 0.10 0.26 0.073
470 1205 1349 73.8 j203 1122 1284 56.5 *
eight; ECM= energy-corrected milk yield.
2�C3.
Fig. 1. Concentrate dry matter intake.
T. Kokkonen et al. / Livestock Production Science 86 (2004) 239–251 243
conjunction with concentrate intake, starch intake was
increased significantly (P < 0.001). No difference was
found in silage DMI.
Milk and fat yields tended to increase (P < 0.10),
and ECM and protein yields increased significantly
(P < 0.05) with a rapid increase of concentrate during
period 1 (Table 3). Milk fat content decreased
Table 4
Feed intake and milk yield, days 36–70
LS LF MS M
Silage DM intake (kg/day)a 8.3 8.8 7.5
Silage DM intake (% LW) 1.28 1.44 1.20
Concentrate DM intake (kg/day) 13.8 13.4 13.8
Total DM intake (kg/day) 22.1 22.3 21.3
ME (MJ/day) 259 261 250
Crude protein (g/day) 3185 3225 3083
AAT (g/day) 2091 2103 2018
PBV (g/day) � 225 � 205 � 210 �Starch (kg/day) 6.6 6.4 6.6
NDF (kg/day) 7.5 7.5 7.2
Milk (kg/day)a 37.6 36.3 38.0
ECM (kg/day) 35.4 33.3 36.4
Fat (g/kg) 35.5 34.0 36.8
Protein (g/kg) 31.6 30.6 31.2
Urea (mg/100 ml) 20.7 21.5 23.4
Acetone + 8 weeks (mmol/l) 0.06 0.03b 0.04b
Fat (g/day) 1313 1219 1383
Protein (g/day) 1184 1108 1183
Abbreviations as in Tables 1 and 2; S.E.M. = standard error of mean; LW
jP < 0.10; *P< 0.05; **P < 0.01; ***P < 0.001.
C1 =L vs. (M+H), C2 =M vs. H, C3 = S vs. F, C4 =C1�C3 and C5 =Ca Significant ( P < 0.05) time effect.b n= 4, S.E.M. = 0.046.
(P < 0.05 and P < 0.10) linearly with the level of
concentrate intake at calving, and protein content
tended to be lower (P < 0.10) in M than in H.
During period 2, no significant differences were
present in silage DMI, total DMI and ME intake (Table
4), nor were there differences in milk or milk compo-
nent yields. Milk urea tended to be lower (P < 0.10) in
F HS HF S.E.M. C1 C2 C3 C4 C5
7.7 7.5 9.3 0.61
1.22 1.24 1.43 0.089
13.8 13.8 13.8 0.11 j j21.5 21.3 23.1 0.68
250 252 270 7.5
2969 3153 3328 92.5 *
2009 2037 2177 56.5
308 � 167 � 222 40.8
6.6 6.6 6.6 0.05 j j7.5 7.0 7.9 0.35
39.4 37.4 40.0 1.71
36.8 34.3 38.2 1.60
35.1 33.3 36.1 1.93
30.7 31.4 31.3 0.57
18.2 25.9 21.2 1.41 j * *
0.07 0.04 0.20 0.041 j *
1390 1244 1455 85.9
1205 1172 1252 50.4
= live weight; ECM= energy-corrected milk yield.
2�C3.
T. Kokkonen et al. / Livestock Production Science 86 (2004) 239–251244
M than in H. Milk urea was also lower (P < 0.05) with
a rapid increase of concentrate, but this effect was not
seen between LS and LF (interaction P < 0.05).
Milk acetone at 1 week after calving (Table 3)
tended to decrease (P < 0.10) between prepartum
concentrate groups (L>M>H). However, at 8 weeks
after calving, milk acetone was highest (P < 0.05) in
H (Table 4). There was also a significant interaction
(P < 0.01) showing increased milk acetone with fast
increase rate of concentrate within M and H, whereas
between LS and LF, an opposite effect was seen. No
difference was observed between treatments in so-
matic cell count (data not shown) during either of the
periods.
3.2. Live weight and feed utilization
In period 1, M groups lost more weight (P <0.05)
than H groups (Table 5) and energy balance tended
Table 5
Live weight, body condition score, energy balance and feed utilization
LS LF MS MF
Days 1–35
Live weight (kg)a 646 617 621 635
Live weight change (kg/day) � 0.68 � 0.46 � 0.68 � 1.
Body condition scorea 3.14 2.79 2.99 3.
Body condition score change � 0.22 � 0.28 � 0.16 � 0.
Energy balance (MJ/day)a,b � 42.7 � 9.5 � 11.0 � 14.
k lc 0.74 0.62 0.64 0.
Protein yield/CP intake (g/g) 0.45 0.41 0.39 0.
AAT/ECM (g/kg)d 36.8 43.5 43.8 46.
Days 36–70
Live weight (kg)a 646 611 624 631
Live weight change (kg/day) � 0.32 0.38 0.34 0.
Body condition score 2.79 2.62 2.88 2.
Body condition score change � 0.28 � 0.06 � 0.06 � 0.
Energy balance (MJ/day) 15.7 31.9 3.5 1.
k lc 0.56 0.59 0.66 0.
Protein yield/CP intake (g/g) 0.37 0.34 0.38 0.
AAT/ECM (g/kg)d 48.3 48.0 42.3 42.
S.E.M. = standard error of mean; kl = utilization of metabolizable energy f
absorbed from the small intestine; CP= crude protein; ECM= energy-corr
jP < 0.10; *P< 0.05; **P < 0.01; ***P < 0.001.
C1 =L vs. (M+H), C2 =M vs. H, C3 = S vs. F, C4 =C1�C3 and C5 =Ca Significant ( P< 0.05) time effect.b Significant ( P < 0.05) interaction treatment� time.c kl = ECM� 3.14/(ME intake�ME allowance for maintenance�ME
MJ/kg LW gain and ME allowance for maintenance is calculated accordid (AAT intake � 3.25�LW0.75�AAT for LWC�LWC)/ECM, AAT
to be lower in M than H cows (P < 0.10). Energy
balance was improved with a rapid increase of
concentrate within L, but not within M or H groups
(interaction P < 0.05). The effect of rapid concentrate
increment on changes of body condition score
(BCS) differed between M and H, showing a
negative effect in M and positive effect in H
(interaction P < 0.01). ME utilization for milk pro-
duction (kl) was lower (P < 0.10) with fast than slow
increase of concentrate. A trend towards decreased
AAT utilization was present with increased concen-
trate intakes.
During period 2, groups LS, HS and HF contin-
ued to lose live weight, whereas the other groups
gained weight (Table 5). The difference between M
and H was statistically significant (P < 0.05). MS
and MF tended (P < 0.10) to have higher ME and
had higher (P < 0.05) AAT utilization than HS and
HF.
HS HF S.E.M. C1 C2 C3 C4 C5
626 661 21.9
50 � 0.14 � 0.46 0.328 *
05 2.78 3.31 0.133 * j36 � 0.32 � 0.08 0.110 **
1 0.6 5.1 8.46 ** j *
56 0.62 0.58 0.048 j *
41 0.40 0.42 0.018 *
2 44.2 46.2 2.24 * j
613 649 21.6
22 � 0.12 � 0.12 0.188 * *
86 2.62 3.23 0.164 j02 � 0.06 � 0.08 0.093
4 17.2 12.8 9.97 j65 0.57 0.59 0.037 j41 0.37 0.38 0.016 j6 48.5 6.2 2.33 *
or milk production; LWC= live weight change; AAT= amino acids
ected milk yield.
2�C3.
of LWC�LWC), where ME of LWC is 28 MJ/kg LW loss and 34
ng to MAFF (1975).
for LWC is 138 g/kg LW loss and 233 g/kg LW gain.
oduction Science 86 (2004) 239–251 245
3.3. Blood composition
No significant differences were observed in blood
composition (Table 6) at the start of the experiment.
One week before calving, plasma glucose concentra-
tion was higher (P < 0.05), and urea (P < 0.05) and
NEFA (P < 0.01) were lower in M and H than in L.
Triglyceride concentration was higher (P < 0.01) in F
than in S, even though no difference between F and S
was present in feeding in prepartum concentrate level
(L, M or H) before calving. BHB was lower
(P < 0.01) in L than in M and H, whereas acetoacetate
was higher (P < 0.05) in H than in M. Insulin was
highest (P < 0.05) in HS and HF. Glucagon was lower
(P < 0.05) in L than in M and H.
One week after calving, LS and MF had the
lowest glucose concentrations (Table 7), and a
significant difference (P < 0.05) was present be-
tween M and H. Urea decreased (P < 0.05) with a
rapid increase of concentrate, and a similar tenden-
cy (P < 0.10) was found with triglycerides. Triglyc-
eride concentration was lower in L than in M and
H. A rapid increase of concentrate decreased ace-
toacetate and BHB concentrations sharply within L,
T. Kokkonen et al. / Livestock Pr
Table 6
Blood composition prepartum
LS LF MS MF H
� 3 weeks
Glucose (mg/100 ml) 66.7 71.1 71.8 70.2 7
Urea (mmol/l) 4.12 3.64 3.90 3.32
Triglycerides (mmol/l) 0.32 0.43 0.37 0.34
Acetoacetate (mmol/l) 0.048 0.040 0.044 0.054
BHB (mmol/l) 0.43 0.43 0.47 0.55
Insulin (AIU/ml) 8.4 8.0 9.2 7.9 1
Glucagon (pg/ml) 90.3 88.8 90.8 98.9 11
� 1 week
Glucose (mg/100 ml) 68.0 70.1 76.3 71.4 7
Urea (mmol/l) 3.76 3.68 3.92 2.90
Triglycerides (mmol/l) 0.32 0.38 0.31 0.39
NEFA (mmol/l) 0.26 0.34 0.21 0.19
Acetoacetate (mmol/l) 0.042 0.032 0.036 0.034
BHB (mmol/l) 0.42 0.39 0.49 0.54
Insulin (AIU/ml) 5.5 10.7 10.3 9.5 1
Glucagon (pg/ml) 56.2 72.7 75.2 79.8 7
S.E.M. = standard error of mean.
jP < 0.10; *P< 0.05; **P < 0.01; ***P < 0.001.
C1 =L vs. (M+H), C2 =M vs. H, C3 = S vs. F, C4 =C1�C3 and C5 =C
but not within M or H (interaction P < 0.10 and
P < 0.05).
One cow in LF had extremely high insulin con-
centration (72 AIU/ml) 4 weeks after calving. Mean,
range and standard deviation of insulin for 29 cows 4
weeks after calving were 9.8, 5.9–20.3 and 3.1 AIU/ml. When all 30 cows were considered, these values
were 11.8, 5.9–72.0 and 11.8 AIU/ml. The sample
that contained 72 AIU/ml was about 20 S.D. away
from the mean of 29 cows. Plasma glucose concen-
tration of the sample was 91.4 mg/100 ml. One week
before blood sampling, the cow was diagnosed with
ketose and was treated with propylene glycol until
blood sampling. It is probable that high insulin and
glucose concentrations were due to administration of
propylene glycol close to blood sampling. The data
from this sample were not used for statistical analysis.
Four weeks after calving, BHB and acetoacetate
were lower (P < 0.05) in L than M and H. Eight
weeks after calving, glucose was lower in F than S,
particularly between HF and HS (interaction P <
0.05). In conjunction with low glucose, HF had the
highest BHB concentration, and BHB was higher
(P < 0.05) in F than S. NEFA were higher (P < 0.05)
S HF S.E.M. C1 C2 C3 C4 C5
1.3 67.6 3.57
3.92 3.22 0.508
0.28 0.33 0.049
0.050 0.050 0.0067
0.51 0.41 0.056
3.8 10.1 1.72
4.7 89.0 11.28
2.6 73.8 2.49 *
3.14 3.14 0.428 * j0.31 0.42 0.037 **
0.21 0.21 0.040 **
0.052 0.060 0.0072 *
0.52 0.55 0.056 **
7.4 17.9 3.52 * *
9.0 73.2 6.88 *
2�C3.
Table 7
Blood composition postpartum
LS LF MS MF HS HF S.E.M. C1 C2 C3 C4 C5
+1 week
Glucose (mg/100 ml) 51.5 61.2 58.1 51.4 65.6 65.5 4.13 * jUrea (mmol/l) 3.20 2.50 2.70 2.34 2.82 2.00 0.399 *
Triglycerides (mmol/l) 0.19 0.18 0.31 0.24 0.30 0.21 0.046 * jNEFA (mmol/l) 0.87 0.63 0.70 0.64 0.84 0.53 0.136
Acetoacetate (mmol/l) 0.35 0.14 0.11 0.17 0.076 0.086 0.0495 * jBHB (mmol/l) 1.88 0.96 0.90 1.21 0.68 0.61 0.221 * *
Insulin (AIU/ml) 5.2 6.8 6.0 6.5 8.0 11.2 2.33
Glucagon (pg/ml) 94.4 111.3 90.9 107.8 94.2 95.1 8.65
+4 weeks
Glucose (mg/100 ml) 63.0 65.2a 62.6 66.0 67.6 63.0 4.17b
Urea (mmol/l) 3.50 2.61a 3.10 3.08 2.98 2.58 0.416b
Triglycerides (mmol/l) 0.20 0.31a 0.26 0.23 0.26 0.21 0.031b **
NEFA (mmol/l) 0.37 0.34a 0.26 0.63 0.34 0.37 0.117b
Acetoacetate (mmol/l) 0.096 0.050a 0.13 0.11 0.11 0.13 0.0478b *
BHB (mmol/l) 0.71 0.52a 1.04 0.93 0.83 1.19 0.329b *
Insulin (AIU/ml) 9.7 10.2a 8.6 8.8 12.2 9.4 1.59b
Glucagon (pg/ml) 94.0 140.8a 118.1 115.8 127.6 134.9 14.89b
+8 weeks
Glucose (mg/100 ml) 70.6 66.8 68.8 67.4 74.1 59.2 2.45 ** *
Urea (mmol/l) 3.10 3.08 3.06 2.66 4.00 3.10 0.294
Triglycerides (mmol/l) 0.20 0.20 0.20 0.23 0.23 0.21 0.024
NEFA (mmol/l) 0.24 0.18 0.22 0.27 0.26 0.29 0.033 *
Acetoacetate (mmol/l) 0.060 0.048 0.046 0.096 0.056 0.15 0.0232 jBHB (mmol/l) 0.42 0.51 0.46 0.93 0.53 1.38 0.192 *
Insulin (AIU/ml) 10.5 11.4 11.2 12.2 11.5 9.2 1.81
Glucagon (pg/ml) 85.2 116.5 116.9 117.8 132.0 131.5 10.74 * j
S.E.M. = standard error of mean.
jP < 0.10; *P< 0.05; **P < 0.01; ***P < 0.001.
C1 =L vs. (M+H), C2 =M vs. H, C3 = S vs. F, C4 =C1�C3 and C5 =C2�C3.a n= 4.b Max S.E.M.
T. Kokkonen et al. / Livestock Production Science 86 (2004) 239–251246
in M and H than in L. Glucagon was lowest in LS
(interaction P < 0.10).
4. Discussion
4.1. Feed intake
Although a slightly increasing trend in ad libitum
intakes of silage postpartum was present between lead
feeding concentrate levels, no statistically significant
differences were found between L, M and H cows. In
an earlier experiment (Aaes et al., 1994), silage DMI
during the first weeks of lactation was higher with
higher concentrate proportion at calving, but this was
mainly due to low control diet intake. In contrast,
Andersen et al. (1999) reported lower silage DMI at
lactation day 8 in cows, which had received higher
concentrate proportion at calving.
Assuming that higher concentrate ration during
lead feeding do in fact stimulate the increase of rumen
epithelium area and VFA absorption, our results show
no positive effect of this on voluntary feed intake
postpartum. However, even a small amount of con-
centrate may be adequate to maintain the rumen
epithelial area, as suggested by Olsson et al. (1997).
Supporting this, Andersen et al. (1999) found no
macroscopic or histological effects of dry cow con-
centrate feeding on rumen epithelium. Concentrate
allowances for their two groups were 1.6 and 4.3 kg
T. Kokkonen et al. / Livestock Production Science 86 (2004) 239–251 247
DM/day during the last week of pregnancy. These
levels are close to the average prepartum L and H
levels in our experiment.
Alternatively, a very high-energy diet and generous
concentrate allowance are needed to induce changes
in rumen epithelium. As noted by Andersen et al.
(1999), positive effects on rumen epithelial area have
been achieved with a high ratio of concentrate to
roughage (3:1) and a high-energy intake.
As shown in Figs. 1 and 2, concentrate allocations
could be increased without disturbances to feed intake
in all F groups after calving, despite high starch
intakes. Furthermore, only two off-feed incidences
were seen, one in LF (lactation days 41–43) and the
other in MS (lactation days 28–29). The absence of
negative effects of high concentrate allocation on
voluntary feed intake may be due to allocation of
concentrate five times a day. We therefore speculate
that no large variation in rumen pH occurred with high
concentrate diets during the first weeks of lactation.
In line with our results, Hernandez-Urdaneta et al.
(1976) reported that abrupt change from a low con-
centrate diet (5% or 20% concentrate prepartum) to a
medium (40%) or high (60%) concentrate total mixed
ration 4 days postpartum caused no adverse effects on
feed intake, and there was a tendency towards higher
DMI with higher concentrate proportion in the diet.
According to Olsson et al. (1998), by contrast, in-
creasing the amount of concentrate from 2 kg/day at
calving to 11 kg/day within 3 weeks decreased forage
Fig. 2. Total dry m
intake. Furthermore, increasing concentrate at a rate of
0.5 kg/day from 2.5 kg at calving to 10 kg/day within
15 days resulted in lower silage DMI than with an
increase rate of 0.3 kg/day within 26 days (Ingvartsen
et al., 2001). The frequency of concentrate feeding
may explain this discrepancy with our results; in
Ingvartsen et al. (2001), cows were given concentrate
only twice a day.
4.2. Milk yield and feed utilization
In general, effects of concentrate proportion in the
prepartum diet on milk yield have been small (Aaes et
al., 1994; Olsson et al., 1997, 1998). Olsson et al.
(1997, 1998) found, however, some tendencies that a
high concentrate allocation (6 or 8 kg DM/day) at
calving increased milk yield during the first weeks of
lactation. This gives some support to our result that
during lactation weeks 1 to 5 a higher milk yield
occurred with the rapid increase of concentrate post-
partum and with a medium or high level of concen-
trate prepartum. This was, however, achieved at the
expense of efficiency of energy utilization.
In agreement with our results, Minor et al. (1998)
found that a higher proportion of dietary non-fibre
carbohydrates increased milk production during early
lactation. Ekern (1972) and Ingvartsen et al. (2001)
found no effect of more liberal feeding of concentrates
on milk yield during early lactation. However, silage
was not fed ad libitum (Ekern, 1972) or a higher
atter intake.
T. Kokkonen et al. / Livestock Production Science 86 (2004) 239–251248
increase rate of concentrate decreased silage DMI
(Ingvartsen et al., 2001). Thus, increased concentrate
feeding did not increase energy intake as in our
experiment.
In contrast to earlier results (Aaes et al., 1994;
Olsson et al., 1997, 1998), increased concentrate allo-
cation during the transition period decreased the fat
content of milk. However, fat yield was not signifi-
cantly depressed between prepartum concentrate levels
and tended to increase with higher milk yield, indicat-
ing that the decrease of fat content was mainly a
dilution effect.
It is noteworthy that the effect of a rapid concentrate
increase (F vs. S) on milk and milk component yields
during period 1 was seen in M and H but not in L.
Although the full amount of concentrate was achieved
only 4 or 7 days later in LF than in the other two F
groups (18, 14 and 11 days after calving in LF, MF and
HF, respectively), the margins of ME and AAT intakes
are sufficient to explain the difference in ECM between
LF and MF. While the HF group had even higher
nutrient intake, its milk yield did not exceed that of
MF. This may be due to higher tissue mobilization in
MF, which is evidenced by a lower insulin concentra-
tion 1 week after calving, higher NEFA concentration 4
weeks after calving, higher BCS and live weight
changes and lower energy balance during lactation
days 1–35.
As noted by Aston et al. (1995), the response to
additional concentrate is not a simple function of
current yield or yield potential because of the compli-
Fig. 3. Crude pro
cating factor of changes in ad libitum silage intake.
Silage DMI usually decreases with increased concen-
trate ration, and it has been proposed that substitution
ratio increases with higher concentrate levels (Øster-
gaard, 1979; Faverdin et al., 1991). Negative associa-
tive effect on digestibility and partitioning additional
nutrients to tissue gain are other factors reducing
responses to additional concentrate. Consequently,
marginal milk yield responses to additional concentrate
supply decrease considerably as the level of concen-
trate feeding increases (Huhtanen, 1998; Ferris et al.,
1998).
The average response of ECM yield to fast increase
of concentrate was 1.68 kg per increased kilogram
concentrate DM during the experiment. This response
is higher than the responses observed with increased
early or mid-lactation concentrate levels (Aston et al.,
1995; Huhtanen, 1998; Kokkonen et al., 2000a). Aston
et al. (1995) reported an average response of 1.02 kg
milk per increased kilogram concentrate DM with
concentrate rations 6, 9 and 12 kg DM/day. Huhtanen
(1998) reviewed some Finnish experiments conducted
after peak yield with average concentrate levels 6.7 and
11.6 kg DM/day and with average response of 0.43 kg
ECM per increased kilogram concentrate DM.
Low CP content of silage may have contributed
to the high milk yield response in the present trial.
As concentrate supply was increased during lacta-
tion days 1–35, CP intake of cows was markedly
higher with fast increase of concentrate and partic-
ularly in groups MF and HF (Fig. 3), since con-
tein intake.
T. Kokkonen et al. / Livestock Production Science 86 (2004) 239–251 249
centrate had higher CP content than silage. Our
earlier study (Kokkonen et al., 2002) showed that a
substantial milk yield response can be achieved
with a moderate level of protein supplementation
during early lactation. Protein supplementation has
also been shown to reduce substitution rate (Thom-
as, 1987). In this study, substitution of concentrate
for silage was low or silage intake tended to
increase with additional concentrate supply. Inclu-
sion of peas in concentrate is another factor, which
possibly contributed to the low substitution rate.
The low rate of degradation of the storage carbo-
hydrates of peas has prevented depression in rumen
pH (Valentine and Bartsch, 1987). This may alle-
viate the depression of fibre digestion with high
level of grain feeding. However, another factor
affecting substitution rate is negative energy bal-
ance. The work of Faverdin et al. (1991) suggests
that substitution rate is reduced during negative
energy balance.
4.3. Blood composition
A decrease of basal insulin level a few weeks
before calving is part of the adaptation of energy
metabolism to the onset of lactation, allowing the
cow to mobilize its tissue deposits. Feeding a high
concentrate ration prepartum apparently interferes
with this mechanism, as HS and HF had higher
plasma insulin concentrations than the other groups
1 week before calving. Olsson et al. (1997) also found
a tendency towards elevated prepartum insulin con-
centrations with a high proportion of concentrate in
the diet.
According to Holtenius (1993), feeding excessive
amounts of concentrate during the dry period may
result in insulin resistance in fat cows. This phe-
nomenon is characterized by increased plasma
NEFA despite a high insulin level and impaired
capacity to utilize glucose. Cows with insulin
resistance may be subjected to ketosis during very
early lactation (Holtenius and Holtenius, 1996). In
the present study, plasma NEFA were at the same
level in M and H groups, despite the difference in
plasma insulin prepartum. Based on average ketone
concentrations of H cows, no signs of elevated risk
of ketosis were present 1 week after calving. In
fact, H groups had a lower concentration of ketones
and a higher concentration of glucose than the other
groups during very early lactation. It is, however,
noteworthy that the cows in groups HS and HF were
in moderate body condition, which in conjunction
with a high-energy intake postpartum probably limit-
ed mobilization of fatty acids. In agreement with our
results, Vik-Mo and Refsdal (1984) stated that im-
proved intakes of liberal amounts of concentrated
feeds and silage ad libitum depressed ketonemia and
reduced incidence of ketosis. Further, Aaes et al.
(1994) reported that cows fed a concentrate-rich
diet prepartum had fewer ketoses during early lacta-
tion. Also consistent with our results, Minor et al.
(1998) found that a higher proportion of dietary non-
fibre carbohydrates during the periparturient period
decreased blood NEFA and BHB concentrations in
early lactation. The decrease of ketone production is
due to decreased substrate (NEFA) availability and/or
the antiketogenic effect of propionate (Grummer,
1993).
HF cows showed a trend towards decreasing
glucose and increasing ketone concentrations at
lactation weeks 4 and 8. These cows were in
positive energy balance and plasma NEFA were
not high. Thus, the increase of blood ketone con-
centrations was not due to excessive lipolysis in
adipose tissue. No reason was found for the in-
creased ketone concentration.
A low concentrate ration prepartum was accom-
panied by slightly elevated plasma NEFA 1 week
before calving, indicating increased lipid mobiliza-
tion. The elevation of plasma NEFA prepartum may
increase fatty acid infiltration of the liver and
contribute to the increased risk of spontaneous
ketosis (Grummer, 1993, 1995). Increased blood
ketone concentrations postpartum were observed
only in LS 1 week after calving. Four weeks after
calving blood ketone concentrations were lower in
L groups than in other groups. As a consequence of
slow increase of concentrate, a sustained energy
deficiency indicated by the negative energy balance
during the first weeks of lactation in LS, and
concomitant increase of plasma NEFA account for
high ketone level in LS 1 week after calving. A
trend (P= 0.12) towards decreased plasma NEFA 1
week after calving with fast increase of concentrate
can be seen within all prepartum concentrate
groups.
T. Kokkonen et al. / Livestock Production Science 86 (2004) 239–251250
5. Conclusions
The proportion of concentrate in the prepartum diet
had no effect on silage DMI postpartum. The daily
concentrate ration postpartum could be rapidly in-
creased without disturbances to feed intake. The rapid
increase of concentrate tended to increase milk and
milk component yields during the first 5 weeks of
lactation but at the expense of decreased efficiency of
energy utilization. In addition, milk fat content de-
creased with increased proportion of concentrate in
the prepartum diet.
A low proportion of concentrate prepartum elevat-
ed plasma NEFA 1 week before calving, and accom-
panied by a slow increase rate of daily concentrate
ration postpartum, it resulted in a more negative
energy balance than in other groups and high blood
ketone values during the first weeks of lactation.
Cows with a high proportion of concentrate prepartum
had elevated blood insulin 1 week before calving, but
this did not have a consistent effect on plasma NEFA.
Acknowledgements
The authors wish to thank Sakari Alasuutari, Jorma
Tossavainen and the staff of the Suitia Research Farm
for conducting the trial. Tuomo Kokkonen received
financial support from the Agricultural Research
Foundation of August Johannes and Aino Tiura.
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