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Roughage intake of simmental, brown Swiss and Holstein Friesian cows fed rations with 0, 25 and 50% concentrates
Livestock Production Science, 27 ( 1991 ) 123-136 Elsevier Science Publishers B.V., A m s t e r d a m
123
Roughage intake of Simmental, Brown Swiss and Holstein Friesian cows fed rations with 0, 25 and 50% concentrates L. Gruber ~, R. Steinwender ~, K. K r i m b e r g e r 1 a n d J. S61kner 2 ~Federal Research Institute for Agriculture in Alpine Regions. Gumpenstein, A 8952 lrdning, Austria 2University of Agriculture Institute of Livestock Sciences, Gregor MendeI-Strafie 33, ,4 1180 Vienna, Austria (Accepted 11 April 1990)
ABSTRACT Gruber, L., Steinwender, R., Krimberger, K. and S61kner, J., 1991. Roughage intake of Simmental, Brown Swiss and Holstein Friesian cows fed rations with 0, 25 and 50% concentrates. Livest. Prod. Sci., 27: 123-136. Two short-term feeding trials (3 weeks on each treatment using a total of 54 lactating cows in a 3 X 3 Latin square design were carried out to determine the ad libitum roughage intake of Simmental (SI), Brown Swiss (BS) and Holstein Friesian (HF) cows, respectively. The cows were fed rations with 0, 25 and 50% of dry matter ( D M ) as concentrates, the rest as roughage. The roughage consisted of 31.5% hay, 38.1% grass silage and 30.4% maize silage. St, BS and HF cows consumed 10.7, 11.0 and 12.2 kg DM day ~ roughage, equivalent to 87, 93 and 105 g kg -°'75 bodyweight. For concentrate groups 0, 25 and 50%, roughage intake decreased from 12.8 to 11.7 and 9.4 kg DM day-~. The substitution rate derived from linear regression was 0.36 kg DM kg-~ DM. The milk yield was increased from 14. l to 16.7 and 19.7 kg by feeding concentrates, while milk protein concentration increased from 3.0 to 3.2 and 3.4% and milk fat concentration decreased from 4.3 to 4.2 and 4.1%. The regressions of forage intake (kg DM ) on milk yield (kg energy-standardized milk ( E S M ) ) showed big differences between breeds, but also between concentrate levels. The regression slopes were 0.04, 0.23 and 0.28 for SI, BS and HF cows. Keywords: breeds: concentrate levels: dairy cattle: roughage intake: substitution rate.
INTRODUCTION
The animal's requirement for energy is probably the main controller of feed intake (Wangsness and Muller, 1981; Forbes, 1986). It is therefore not surprising that lactating cows of dairy breeds have often shown higher feed intake compared with lower yielding dual-purpose cows (e.g. Zaugg, 1976; Oldenbroek and van Eldik, 1980). In many of these studies the roughage intake 0301-6226/91/$03.50
© 1991 - - Elsevier Science Publishers B.V
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data are confounded with the concentrate level because of feeding concentrate according to milk production. When given identical rations (Oldenbrock, 1984) or at least the same concentrate level (Korver, 1982) Holstein Friesian cows consumed significantly more roughage than Dutch Friesian COWS.
According to the cattle breeds used in Austria the comparison between Simmental, Brown Swiss and Holstein Friesian cows is interesting. As there is little information in the literature concerning these breeds an experiment was carried out to study the roughage intake of Simmental, Brown Swiss and Holstein Friesian cows on identical rations. MATERIALS AND METHODS
Experimental design Two identical feeding trials ( 1986 and 1987 ) were carried out at the experimental farm of the institute using a 3 X 3 Latin square design within each breed. The treatments were three concentrate levels (0, 25 and 50% of total DM intake ). One dual-purpose (Simmental, SI ) and two dairy breeds (Brown Swiss, BS and Holstein Friesian, HF) were investigated. Within each breed nine animals were used every year and they represented three stages of lactation (early, m e d i u m and late), consisting of three animals each. The experimental design is shown in Table 1. Each period lasted for 3 weeks; the results, however, were only calculated from the last 2 weeks of each period.
Test animals The cows used in the trials are characterized in Table 2. As usual in Austria, cows of dairy breeds (BS and HF) originated from US pedigree sires. In the case of the dual-purpose Simmental breed, the cows represented the native herd. The SI, BS and HF cows are descended from nine, seven and eight different sires, respectively. At the onset of the experiment the three breeds differed distinctly in liveweight and milk yield, but there were no important differences in age and stage of lactation. Eight of 27 animals from the first year were used in the second experiment.
Measurements, sampling and analyses' Individual feed intake and milk yield were recorded each day throughout the experiment. The composition of the milk (fat, protein and lactose) was analysed from each milking (0400 h and 1600 h) by near-infrared spectroscopy (Milko scan 93, FOSS Electric). Samples of the different feeding stuffs were taken each morning to determine the DM content by oven drying ( 105 °C, 24 h). The samples were bulked for 1 week to analyse the content of the Weende crude nutrients and minerals. The digestibility and energy concentration were determined by the in vitro gas production method (Menke
125
ROUGHAGE INTAKE OF COWS FED CONCENTRATES
TABLE 1
The experimental design Breed Simmental (SI)
Brown Swiss ( BS )
Holstein Friesian ( HF )
Cow nos. Cow nos. Cow nos. Cow nos. Cow nos. Cow nos. Cow nos. Cow nos. Cow nos. 1,2,3 ~ 4,5,6 7,8,9 1,2,3 4,5,6 7,8,9 1,2,3 4,5,6 7,8,9
Period 1 SI 02 Period2 S125 Period3 S150
SI 252 SI50 SI 0
SI 502 SI 0 SI25
BS 0 BS25 BS50
BS 25 BS50 BS 0
BS 50 BS 0 BS25
HF 0 HF25 HF50
HF 25 HF50 HF 0
HF 50 HF 0 HF25
LCow n u m b e r 1,4,7: early stage of lactation; cow n u m b e r 2,5,8: medium stage of lactation: cow n u m b e r 3,6,9: late stage of lactation. -'Concentrate level: 0, 25 and 50% of total DM intake, respectively, i.e. SI 25 indicates Simmental cows
given concentrates at 25% of total DM intake. TABLE2 Some characteristics of the test cows in the preliminary period ( n = 18 )
Traits
S1
BS
HF
Liveweight ~ (kg) Milkyield(kgESM) 2 Age ( d a y s ) Parity
641 _+ 13 15.7 + 1.2 1661 _+58 2.67"+ 0.20
574 + 15 15.3 + 1.1 1397 _+89 1.72"+ 0.21
567 _+ 12 20.9 _+ 1.2 1438 _+86 1.94_+ 0.21
Stage of lactation Early ( d a y s )
Medium ( d a y s ) Late ( d a y s )
65 144 236
_+ 16 _+ 9 _+ 16
85 178 254
_+ 9 "+17 "+ 14
65 113 199
-+ 13 "+10 ± 16
~Mean of eight measurements during the experiments. 2ESM = e n e r g y - s t a n d a r d i z e d milk ( 3.14 MJ k g - t ) according to Bickel ( 1988 ).
and Steingal3, 1988 ) in the first year. In the second year in vivo digestibility trials using four wethers for each single feedingstuff were conducted according to van Es and van der Meer (1980). The liveweights were recorded on two consecutive days at the beginning of each period and at the end of the third period. Body measurements were taken once in the middle of each period.
Feeds and feeding The roughage consisted of equal parts ( D M ) of hay, grass silage and maize silage and was offered at each meal (0330-0730 h and 1430-1830 h ) as single feedstuffs ad libitum ( 5-10% refusals ), not as a mixed ration. The ration was computed every other day taking in consideration the previous feed intake of the period. Within each meal the sequence of feeding was: 50% of concentrates, grass silage, maize silage, 50% of concentrates, hay. The concentrate
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L. GRUBER ETAL.
TABLE 3 Content o f crude nutrients, minerals, digestibility and energy concentration of the feedingstuffs used in both years (in DM, mean o f six analyses) Feedingstuff Year
DM l (%)
XP: (g)
XL 2 (g)
XF 2 (g)
XA 2 (g)
Ca 3 (g)
p3 (g)
DOM 4 (%)
Hay
1 2
86.5 86.9
104 120
2t 23
284 305
83 92
6.8 7.4
3.3 3.6
66.1 65.7
Grass silage
1 2
44.4 24.0
143 156
33 41
299 308
112 135
8.7 9.5
3.7 4.4
Maize silage
1 2
23.4 25.6
83 83
25 29
305 226
54 63
3.6 3.7
Concentrate
1 2
87.0 86.6
171 184
25 23
45 45
50 53
8.5 9.0
ME 5 (MJ)
NEL 5 (MJ)
NEF 5 (MJ)
9.20 9.05
5.43 5.29
5.15
68.8 64.9
9.45 8.60
5.60 4.98
5.10
2.3 2.8
64.2 70.0
9.28 10.57
5.50 6.39
6.00
5.4 5.7
85.2 81.4
13.17 12.39
8.30 7.78
6.68
DM = dry matter. zXP, XL, XF, XA = c r u d e protein, fat, fibre, ash, respectively. 3Ca, P = c a l c i u m , phosphorus. 4DOM = digestibility o f organic matter. 5ME, NEL, N E F = metabolizable energy, net energy lactation, net energy fat (G.D.R.).
was composed of 48.5% barley, 30% maize, 18% soybean meal and 3.5% mineral/trace element mix. The chemical composition and energy concentration of the feedingstuffs used is shown in Table 3. The quality was similar in both years, with the exception of DM content of the grass silage and energy concentration of maize silage. Both hay and grass silage were cut in a rather late stage of vegetation.
Statistical analyses The data were analysed by the " m i x e d model least-squares and m a x i m u m likelihood" computer programme (Harvey, 1985) supposing the following model: Yi-o where Yi-o /t bi
Pk S/
Ym Cn
(be)in ei_o
= lt+ bi+ao+pk + st+ ym+Cn+ ( bc)in+e~-o = observed value of the various traits, = least squares mean, = f i x e d effect o f i t h breed, i = 1,2,3, = r a n d o m effect o f j t h animal within ith b r e e d , j = 1,2 ..... 46, = fixed effect of kth parity, k = 1,2,3, = fixed effect o f lth stage of lactation, l = 1,2,3, = fixed effect o f ruth year, m = 1,2 = fixed effect o f nth concentrate level, n = 1,2,3, = interaction between ith breed and nth concentrate level, = error term.
ROUGHAGE INTAKE OF COWS FED CONCENTRATES
127
The pairwise comparisons of groups were computed according to the Bonferroni-Holm test (EB1, 1987 ). The data are presented as least-square means together with the row-pooled standard error (SE) within groups. Within each treatment row, values with different superscripts are significantly different from each other ( P < 0.05 ). Different regression calculations presented in this paper were based on the same model.
RESULTS
Feed intake The feed intake data in Table 4 show highly significant differences between the three concentrate and the three breed groups. The total DM intake increased linearly from 12.8 to 18.5 kg by adding concentrate to the roughage diet while the roughage intake decreased from 12.8 to 9.4 kg DM. The mean substitution rate over all breeds derived from linear regression analysis was 0.36 kg roughage DM k g - ' concentrate DM, with 0.37, 0.38 and 0.34 for SI, BS and HF cows, respectively. The differences in substitution rate between breeds were not significant. The regression of roughage (and total) intake on concentrate intake was linear and not quadratic. The energy supply was increased from 72 to 125 MJ net energy lactation(NEL) day- 1, corresponding to 5.9 MJ NEL kg- 1 DM concentrate. The animals consumed 2.1,2.8 and 3.5 times their maintenance requirement (293 kJ NEL kg BW-°-75; GEH, 1986) in concentrate levels of 0, 25 and 50%. There were significant interactions in energy supply (metabolizable energy (ME), NEL ) between concentrate level and breed. The HF cows improved their energy intake by feeding concentrates to a higher degree than BS or SI cows. The HF cows had a significantly higher feed intake capacity than the two TABL E 4 Daily feed intake Traits
Roughage (kg D M ) Concentrate (kgDM)*** Total ( k g D M ) Energy ( M J ME)*** Energy (MJ NEL)*** Energy b a l a n c e ~ (MJ N E L ) * * F e e d i n g level 2.**
C o n c e n t r a t e level (%)
Breed
SE
0
25
50
S!
BS
HF
12.84 a 0.00 a 12.84" 122-03 a 72.12 ~ -6.63 ~ 2.06"
I 1.71 b 3.90 b 15.62 b 159.67 b 96.27 b 9.63 b 2.76 b
9.37 c 9.16 c 18.53 c 204.74 c 125.45 c 28.69 c 3.54 c
10.74 a 4.08" 14.82 a 153.96 a 92.95" 15.24 a 2.54 a
11.00 a 4.21 ~ 15.21 a 157.20 ~ 94.98 ~ 10.29 ~b 2.72 b
12.20 b 4.76 b 16.96 b 175.28 b 105.91 b 6.15 b 3.10 c
**,***Interaction ( c o n c e n t r a t e × breed ) on a P < 0.01, P < 0.001 level, respectively, ~Calculated from energy i n t a k e m i n u s energy r e q u i r e m e n t ( G E H , 1986 ). 2Multiple of m a i n t e n a n c e r e q u i r e m e n t (energy i n t a k e / m a i n t e n a n c e r e q u i r e m e n t ; G E H , 1986 ).
0.91 0.61 1.08 9.50 5.80 5.58 0.15
128
L. GRUBER ET AL
160]
z
-4
A
o
,
E
~
~
100-
v
80-
~
60-
•~
40-
20 O.
SI 0
BS 0
HF 0
SI 25
BS 25
HF 25
SI 50
BS 50
HF 50
Fig. 1. Roughage and total feed intake related to metabolic bodyweight o f cows at different concentrate levels.
other breeds, which did not differ significantly from each other. Expressing feed intake per unit metabolic bodyweight the proportional differences became greater because of the higher weight of the SI cows (Fig. 1 ). Given the all-roughage ration the HF cows consumed 18% more than SI cows. Feeding a ration with 50% concentrate, they were superior by 25%.
Ration characteristics In Table 5 it can be seen that the average roughage ration consisted of 31.5% hay, 38.1% grass silage and 30.4% maize silage. The proportion of concentrate (0, 25.0 and 49.4%) also corresponded well to the experimental plan. The small deviations in the roughage proportions are caused by the fact that some animals preferred grass silage. The DM content of the total ration increased and crude fibre content decreased as a consequence of increasing concentrate levels. The protein content rose from 11.7 to 14.7%, and the energy concentration from 9.4 to 11.0 MJ ME. Therefore the protein/energy ratio of almost 13 was similar in all concentrate levels.
Milk yield and composition The mean actual and energy-standardized milk (ESM) yield differed significantly between the breeds ( P < 0.001 ). The daily ESM yield amounted to
129
ROUGHAGE INTAKE OF COWS FED CONCENTRATES T ABLE 5
Composition and characteristics of the ration Traits
Hay (% o f roughage D M ) Grass silage (% of roughage DM ) Maize silage (% of roughage DM ) Concentrate (% of total D M ) DM content (%) XP content ( g k g -~ D M ) XFcontent (gkg -t DM) ME c o n t e n t ( M J kg -~ D M ) Protein/energy (g XP MJ -~ M E )
Concentrate level (% )
Breed
0
25
50
SI
31.8 37.9 30.2 0" 36.3 a 117 a 289 a 9.37 a 12.5 ~
31.0 38.0 31.0 25.0 b 42.0 b 132 b 227 b 10.23 b 12.9 b
31.5 30.9 ab 38.4 38.5 30.1 30.5 49.4 c 24.7 50.4 c 42.8" 147 c 132 168 c 228 11.04 ~ 10.21 13.3 c 12.9
SE BS
HF
33.1 b 37.4 29.5 24.8 43.6 b 132 228 10.22 12.9
30.4 a 38.3 31.3 24.9 42.3 ~ 132 228 10.21 12.9
2.4 3.5 1.9 1.6 1.4 3 7 0.18 0.3
TABLE 6
Daily milk yield and composition Traits
Milk yield (kg)*** Fat content (%)** Protein content (%)*** Lactose content (%) Milk yield (kg ESM)***
Concentrate level (% )
Breed
SE
0
25
50
SI
BS
HF
13.88 a 4.32 a 3.04 a 4.81 14.09 a
16.56 b 4.17 b 3.18 b 4.80 16.67 b
19.44 c 4.11 b 3.39 c 4.85 19.70 ~
13.16 a 4.11 3.41 ~ 4.83 13.36 a
15.69 b 4.24 3.21 a 4.83 15.95 b
21.03 " 4.25 2.98 b 4.80 21.09'
1.28 0.18 0.14 0.12 1.43
**,***Interaction (concentrate X breed ) on a P < 0.01, P < 0.001 level, respectively.
13.4, 16.0 and 21.1 kg for the SI, BS and HF cows (Table 6 ). There were only small differences in the concentration of milk fat. In milk protein concentration, however, the HF cows reached a value of only 2.98%, compared to 3.21 and 3.48% for the BS and SI cows. By feeding concentrates the mean milk yield over all breeds increased from 14.1 to 19.7 kg ESM (Table 6 ). The influence of both energy supply and concentrate level on milk protein and fat concentration is clearly demonstrated and presumably reflects previously demonstrated physiological relationships: milk protein concentration is increased from 3.0 to 3.4% presumably due to improved microbial protein synthesis (energy supply) and milk fat concentration is reduced from 4.3 to 4.1% presumably due to the narrower acetic/ propionic acid ratio caused by an increased concentrate proportion. Significant interactions between concentrate level and breed for milk production traits were detected as clearly demonstrated in Figs. 2 and 3. The actual milk yield was improved by adding concentrates to the ration in Hol-
130
L. GRUBER
ET
,
•
AL
25
20
o~
7
• " oO
•"
o c'q
LI~ C'q
J
15
v
10 -,e m
0
f
SI 0
BS 0
HF 0
SI 25
BS 25
HF 25
SI 50
BS 50
HF 50
Fig. 2. Theoretical milk yield (ESM) from roughage and actual milk yield (ESM) of cows at different concentrate levels.
4.5-
4
5.5J
)'x
c
2
g
3-
c
2.5c
'6 ka_
1.5
SI 0
SI 25
SI 50
BS 0
BS 25
BS 50
HF 0
Fig. 3. Fat and protein content of milk at different concentrate levels.
HF 25
HF 50
131
ROUGHAGE INTAKE OF COWS FED CONCENTRATES TABLE 7 kiveweight and body m e a s u r e m e n t s Traits
Liveweight (kg) Liveweight change (g d a y - ' ) W i t h e r height ( c m ) Body length ( c m ) Chest girth ( c m ) D e p t h o f chest ( c m )
C o n c e n t r a t e level (%)
Breed
SE
0
25
50
SI
BS
HF
592.2 a - 370 a 133.9 166.2 193.4 72.2
590.1 a 717 b 133.8 166.4 193.4 72.4
601.5 b 525 b 134,2 166,3 194,4 72.5
625.2" 347 131.8 a 164.0" 196.3 71.9
588.3 ab 330 134.3 ab 166.4 ab 192.4 72.4
570.3 b 194 135.8 b 168.4" 192.4 72.8
15.4 710 1.0 1.7 2.0 1.1
stein cows to a much higher extent (from 17.3 to 25.1 kg ESM) than in Simmental cows (from 11.8 to 14.7 kg ESM). The Brown Swiss were intermediate (Fig. 2 ). The theoretical milk yield from the roughage was depressed by concentrate level from 11.7 to 5.2 kg ESM. The protein concentration in milk of HF cows was extraordinarily low (2.77%) in the all-roughage group presumably due to the marked energy deficit on this ration. The high fat concentration of this group (4.49%) could be caused partly by a high fat mobilization. At the high concentrate level the differences in milk composition between breeds were not as large as in the roughage group (Fig. 3 ).
Body measurements The data concerning the body measurements are presented in Table 7. The average liveweights for SI, BS and HF cows were 625, 588 and 570 kg. According to the milking potential SI cows gained more weight than BS and HF cows. The dairy cows (BS and H F ) were higher and longer whereas SI cows showed a higher chest girth. The influence of concentrate level can be seen more or less in the liveweights with a tendency of higher weights at higher concentrate levels and also by a substantial loss of liveweight in the roughage group, whereas the animals gained weight when fed concentrate. No interactions occurred between concentrate level and breed. DISCUSSION AND CONCLUSIONS
Breeds Across rations in the present study Brown Swiss and Holstein cows consumed by 6 and 20% more roughage than Simmental cows k g - ' metabolic bodyweight. This is in line with Swiss investigations of Zaugg (1976) and Bieri ( 1982 ). On the other hand some German authors using Simmental and Red Holstein cows found only slight differences (Pallauf and KirchgeBner, 1976; Lindermayer, 1986). Hafez et al. (1989) found a superiority of HF
132
L.GRUBERETAL.
over Red and White cows of 6% in roughage intake related to metabolic bodyweight. Comparing Dutch Friesian with HF cows Oldenbroek (1979) and Oldenbroek and van Eldik (1980) found minor differences of 7 and 2%, respectively. In all these cases roughage intake is confounded with concentrate level by feeding concentrate according to milk yield. Feeding identical rations (all roughage or equal concentrate portion) HF cows consumed 5% (Rohr, 1972) and 4% (Oldenbroek, 1984) more than German and Dutch Friesian cows. Korver ( 1982 ) found hardly any difference under similar situations. It can be concluded that the superiority of Holsteins for roughage intake of 20% in the present study lies in the upper range of literature data, and that Holstein cows are clearly able to consume more than Brown Swiss. However, to make the results comparable, identical rations should be fed to all types of cows and intake should be related to metabolic bodyweight.The differences in roughage intake between Simmental and HF cows in the present study are larger than between Black and White and HF cows in other studies. Across breeds, higher feed intake is accompanied by higher milk yield in all the abovementioned publications.
Concentrate level From the recent and comprehensive review of Kleinmans and Potthast (1984) it can be concluded that - apart from factors related to the animal the quality of roughage and the proportion of concentrate are the most important determinants of roughage intake. There is also clear evidence that the substitution rate increases progressively with increasing amounts of concentrate (Ostergaard, 1979; Schwarz and KirchgeBner, 1985; Gruber, 1988 ). In the present study, however, no curvilinearity could be detected. This is in agreement with the results of Ward and Kelley (1969) and Kristensen and Norgaard (1987), when feeding hay and grass silage as the only roughage. The physiological reason for this linear decrease of roughage intake could lie in the feeding strategy of giving the concentrate in two separate doses (Kaufmann, 1976) and that the total concentrate proportion did not exceed 50%. A third possible reason is that concentrate and roughage intake (within one concentrate level) are positively correlated because of the experimental plan of feeding concentrate not as a fixed amount but as a certain percentage of the diet. But when concentrate level is expressed as a percentage of total DM intake (C%), roughage intake (RI, kg DM) could be best described by the following quadratic regression equation: R I = 11.68-0.071 X ( C % - 2 5 ) - 0 . 0 0 1 0 3 X ( C % - 2 5 ) 2 C V = 10.2, R2=0.71 It was not intended that this experiment should study the effect of concentrate on milk yield. However, the results with regard to differences between
ROUGHAGE INTAKE OF COWS FED CONCENTRATES
I33
breeds are interesting. Regressions of yield on concentrate intake were linear rather than curvilinear and - across the breeds - the milk yield increased by 0.63 kg ESM kg- 1 DM concentrate. There were, however, significant differences ( P < 0 . 0 5 ) between breeds with linear regression coefficients of 0.36, 0.73 and 0.81 for breeds SI, BS and HF. That means that dairy breeds converted the additionally offered energy into milk production to a much larger extent whereas dual-purpose cows gained bodyweight. It should be kept in mind that the effect of concentrate level on milk yield in the present study may be partly influenced by carry-over effects and by the short duration of the experiment. Concerning the effect of concentrate on roughage intake it can be concluded that a mean substitution rate of 0.36 determined in the present study is typical of this concentrate level (up to 50% of total ration) in connection with the m e d i u m quality of roughage (9.4 MJ ME kg -1 DM). The low efficiency of concentrate with regard to milk yield (0.63) is a consequence of the experimental plan of feeding concentrate not according to milk yield so that the energy supply exceeded the yield achieved especially in the dual-purpose breed (SI).
Milk yield-feed intake correlation The regressions of roughage and total feed intake on milk yield showed big differences between breeds, but also between concentrate levels (Fig. 4). Over all rations, SI, BS and HF cows increased their total feed intake by 0.09, 0.31 and 0.37 kg DM and their roughage intake by 0.04, 0.23 and 0.28 kg DM kgincrease in ESM, respectively. From Fig. 4 it is easily seen that the slopes for roughage intake are typically higher both for the all-roughage rations and for the dairy breeds. These are situations where energy deficit is likely to be substantial and animals try to compensate for their energy deficit. In groups SI 0, BS 0 and HF 0 the cows consumed 101, 92 and 79% of their energy requirements (based on recommandations of GEH, 1986). In contrast the cows fed 50% concentrate were over-supplied ( 192, 154 and 132%). Lindner et al. ( 1981 ) found significant correlations of feed intake on milk yield only for first lactating but not for older cows with rations of 25% concentrate. On average, however, the older cows were over-supplied in energy corresponding to 3.5 kg FCM. On the other hand Journet and R e m o n d (1976) found clear positive relationships between milk yield and feed intake when offering all roughage diets (grass or maize silage). It can be concluded that cows try to compensate for a substantial energy deficit by increasing both their total feed and their roughage intake. A possible reason for the different regression slopes between the dual-purpose group and the dairy groups may lie in different mechanisms of partitioning the nutrients. Dual-purpose cows tend to use nutrients to gain bodyweight to a higher degree than dairy cows. Low-yielding dual-purpose cows probably
134
L. G R U B E R
BROWN SWISS
SIMMENTAL
HOLSTEIN FRIESIAN r~'~m~
17
T,~TqT.. r , , I . . . . p ~ ]
l bl= 0.27 i b2= 0.25
1
17
[ bl= 0.55 j b2= 0.33
]
bl =-0.01 b2= 0.10 b3= 0.03
E T AL.
L b3= 0.17
b3= 0.18
1 1
1
z '
I Ij
14.5
tm 14.5 O~ 1
1
ij~ zl :
' 0 -,.-, ¢._
, a 09
~ 12
12 ~12
a '
2 2~2 3
0¢-
3
9.5
2
b5
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. _C
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~I~a 3
3 /
0
c"
3
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2
9.5
3
o
~ 0
Q£
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7 L L ~ _ L L ~ : I ~ ± I ~ L ~l ,~= 5 15 25 35
7 1± k~ J l*a 1 [m
5
15
~I a u a [
L~ ~ J l
25
k~
35
5
15
25
35
Milk yield (kg ESM) Milk yield (kg ESM) Milk yield (kg ESM) Fig.4. Relationship between milk yield (kg ESM) and roughage intake (kg DM) of cows at different concentrate levels.
eat the same amount of feed as the high yielders because they use the excess nutrients for bodyweight gain. When the requirement for bodyweight gain is taken into account additionally to the requirement for milk production, the results of this study are in line with the hypothesis that energy balance regulation is the main drive for feed intake (Wangsness and Muller, 1981; Forbes, 1986).
REFERENCES Bickel, H., 1988. Fat-corrected milk (FCM), an inaccurate and confusing term. Livest. Prod. Sci., 18: 311-313. Bieri, P., 1982. Produktionstechnische und wirtschaftliche Untersuchungen fiber den Futteraufwand bei Milchkfihen w~ihrend der Laktation. Diss. ETH Nr. 7140, Ztirich, 190 pp. EBI, A., 1987. Statistische Methoden in der Tierproduktion. Verlagsunion Agrar, Wien, 104 pp. Forbes, J.M., 1986. The Voluntary Food Intake of Farm Animals. Butterworths, London, p. 3. GEH (Gesellschaft ffir Ern~ihrungsphysiologie der Haustiere, Ausschuss f'fir Bedarfsnormen), 1986. Energie- und Nahrstoffbedarf landwirtschaftlicher Nutztiere, Nr. 3: Milchkfihe und Aufzuchtrinder. DLG-Verlag, Frankfurt (Main), 13 pp. Gruber, L., 1988. Grundfutteraufnahme bei Rindern: Fiitterungsaspekte. Symposium "Produktion von Milch und Rindfleisch auf der Basis von wirtschaftseigenem Futter", Leipzig 17 March, Polycopy Gumpenstein, 25 pp.
ROUGHAGE INTAKE OF COWS FED CONCENTRATES
l 35
Hafez, S., Junge, W., Hagemeister, H. and Kalm, E., 1989. Futteraufnahme und Futterverwertung der Rassen Rotbunt, Schwarzbunt und Red-Holstein × Rotbunt unter Laufstallbedingungen. Zfichtungskunde, 61:41-54. Harvey, W.R., 1985. User's guide to LSMLMW. Mixed model least-squares and maximum likelihood computer program. Polycopy Ohio State University. Journet, M. and Remond, B., 1976. Physiological factors affecting the voluntary intake of feed by cows: A review. Livest. Prod. Sci., 3: 129-146. Kaufmann, W., 1976. Influence of the composition of the ration and the feeding frequency on pH-regulation in the rumen and on feed intake in ruminants. Livest. Prod. Sci., 3:103-114. Kleinmans, J. and Potthast, V., 1984. Zur "Verdrgngung" von Grundfutter dutch Kraftfutter in der Milchviehffitterung. Obers. Tierern~ihrung, 12:165-186. Korver, S., 1982. Feed intake and production in dairy breeds dependent on the ration. Diss. Wageningen, 139 pp. Kristensen, V.F. and Norgaard, P., 1987. Effect of roughage quality and physical structure of the diet on feed intake and milk yield of the dairy cow. Research in Cattle Production Danish Status and Perspectives. Det kgl. danske Landhusholdningsselskab, pp. 79-91. Lindermayer, H.. 1986. Futteraufnahme, Futterverwertung und Wirtschaftlichkeit von Doppelnutzungsrasse und Milchrasse fiber die Dauer einer ganzen Zwischenkalbezeit. Diss. TU Miinchen-Weihenstephan, 184 pp. Lindner, H.P., Kirchgel3ner, M. and Schwarz, F., 1981. Zur Futteraufnahme von Kfihen in Abhi~ngigkeit v o n d e r Milchleistung. Ziichtungskunde, 53: 99-112. Menke, K.H. and Steingag, H., 1988. Estimation of the energetic feed value obtained from chemical analysis and in vitro gas production using rumen fluid. Anim. Res. Dev., 28: 7-55. Oldenbroek, J.K., 1979. Differences in the intake of roughage between cows of three breeds fed two levels of concentrates according to milk yield. Livest. Prod. Sci., 6: 147-151. Oldenbroek, J.K., 1984. Holstein Friesians, Dutch Friesians and Dutch Red and Whites on two complete diets with a different amount of roughage: Performance in first lactation. Livest. Prod. Sci., 11 : 401-415. Oldenbroek, J.K. and van Eldik, P., 1980. Differences in feed intake between Holstein Friesian. Dutch Red and White and Dutch Friesian Cattle. Livest. Prod. Sci., 7:13-23. Ostergaard, V., 1979. Strategies for concentrate feeding to attain optimum feeding level in high yielding dairy cows. 482. Beretning Statens Husdyrbrugs Forsog, Kobenhavn, 138 pp. Pallauf, J. and Kirchgel3ner, M., 1977. Zur Grundfutteraufnahme von Milchkiihen der Rasse Deutsches Fleckvieh und Red Holstein Frisian-Kreuzungen. Zfichtungskunde, 19:120-137. Rohr, K., 1972. Untersuchungen fiber die Futteraufnahme und Futterverwertung bei Milchkfihen verschiedener Rassen unter besonderer Bedicksichtigung des Grfinfutters. Kiel. Milchwirtsch. Forschungsber., 24: 23-96. Schwarz, F.J. and Kirchgel3ner, M., 1985. Grundfutteraufnahme von Milchkiihen in Abhi~ngigkeit von Lebendgewicht, Zahl der Laktationen, Krafffutterzufuhr und Grundfutterqualit~it. Ziichtungskunde, 57: 267-277. Van Es, A.J.H. and van der Meer, J.M., 1980. Methods of analysis for predicting the energy and protein value of feeds for farm animals. Workshop on methodology of analysis of feeding stuffs for ruminants, Lelystad, NL, 27-29 May, 106 pp. Wangsness, P.J. and Muller, L.D., 1981. Maximum forage intake for dairy cows. Review. J. Dairy Sci., 64: 1-23. Ward, G.M. and Kelley, P.L., 1969. Influence of roughage-to-concentrate ratios on ad libitum consumption by lactating cows. J. Dairy Sci., 52:1017-1019. Zaugg, U., 1976. Vergleichsversuch mit Braunvieh, Simmentaler Fleckvieh und Holstein Friesian amerikanischer Herkunft. Diss. ETH Nr. 5671, Zfirich, 121 pp.
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L GRUBERETAL.
RESUME Gruber, L., Steinwender, R., Krimberger, K. et S61kner, J., 1991. Consommation de fourrages par les vaches Simmental, Brown Swiss et Holstein Friesian recevant des rations contenant 0%, 25% et 50% de concentres. Livest. Prod. Sci., 27: 123-136 (en anglais). Pour mesurer la consommation ad libitum de fourrages par des vaches Simmental (SI), Brown Swiss (BS) et Holstein Friesian (HF), on effectu6 deux essais d'alimentation en cart6 latin (3X3) de courte dur6e (3 semaines par traitement) sur un total de 54 vaches. Les rations comportaient 0%, 25% ou 50% de la MS sous forme de concentr6s et le fourrage 6tail un m61ange de 31,5% de foin, 38,1% d'herbe et 30,4% d'ensilage de ma'fs. Les vaches SI, BS et HF ont consomm6 respectivement 10,7:11,0 et 12,2 kg de MS de fourrages par jour soit 87, 93 et 105 g par kg de poids m6tabolique (po.vs). La consommation de fourrage a 6t6 de 12,8; 11,7 et 9,4 kg de MS par jour avec les rations conlenant respectivement 0%, 25% el 50% de concentr6s, le taux de substitution calcule par regression lineaire 6tan! de 0,36. La production laitibre ( 14,1; 16,7 el 19,7 kg par jour) et la teneur en proteines du lair (3,0:3,2 et 3,4%) ont augment6 avecla proportion de concentr6 landis que le taux butyreux diminuait (4,3; 4,2 el 4,1%). Les coefficients de r6gression de la quanlil6 de fourrage consomme (kg de MS par jour) par rapport ~ la production laitibre (kg par jour) onl differ6 avec la race (0,04:0,23 et 0,28 pour les vaches SI, BS et HF) et aussi avec la proportion de concentr6. KU RZFASSUNG Gruber, L., Steinwender, R., Krimberger, K. und S61kner, J., 1991. Grundfutteraufnahme von Fleckvieh, Brown Swiss und Holstein Friesian Kiihen bei Rationen mit 0, 25 und 50% Kraftfutter. Livest. Prod. Sci., 27:123-136 (aufenglisch). In einer Versuchsanlage nach dem lateinischen Quadrat wurden zwei kurzffistige Fiitterungsversuche (3 Wochen je Behandlung) mit insgesamt 54 laktierenden Kfihen durchgef'tihrt, um die ad libitum Grundfutteraufnahme der Rassen Fleckvieh (SI), Brown Swiss (BS) bzw. Holstein Friesian (HF) festzustellen. Die Kfihe erhielten Rationen mit 0, 25 bzw. 50% der Trockenmasseaufnahme als Kraflfutter, das Grundfutter bestand aus 31,5% Heu, 38,1% Gras- und 30,4% Maissilage. Die t~gliche Grundfutteraufnahme der SI, BS bzw. HF Kfihe betrug 10,7, 11,0 bzw. 12,2 kg TM, pro kg metabolischem K6rpergewicht 87, 93 bzw. 105 g. In den Kraftfutterstufen 0, 25 und 50% ging die Grundfutteraufnahme von 12,8 auf 11,7 und 9,8 kg TM zurfick. Die Grundfutterverdr~ingung, abgeleitet mit Hilfe einer linearen Regression, ergab einen Weft von 0,36 kg TM kg -~ TM. Durch das Kraftfutter wurde die Milchleistung von 14,1 auf 16,7 bzw. 19,7 kg gesteigert, ebenso der Gehalt an MilcheiweiB yon 3,0 auf 3,2 bzw. 3,4%. Doch der Milchfettgehalt sank von 4,3 auf4,2 bzw. 4,1%. Die Regressionen zwischen Grundfutteraufnahme (kg TM) und Milchleistung (kg ESM) zeigten groBe Unterschiede zwischen den Rassen, jedoch auch zwischen den Kraftfutterstufen. Die Regressionskoeffizienten betrugen 0,04, 0,23 und 0,28 f'tir SI, BS und HF Kfihe.
123
Roughage intake of Simmental, Brown Swiss and Holstein Friesian cows fed rations with 0, 25 and 50% concentrates L. Gruber ~, R. Steinwender ~, K. K r i m b e r g e r 1 a n d J. S61kner 2 ~Federal Research Institute for Agriculture in Alpine Regions. Gumpenstein, A 8952 lrdning, Austria 2University of Agriculture Institute of Livestock Sciences, Gregor MendeI-Strafie 33, ,4 1180 Vienna, Austria (Accepted 11 April 1990)
ABSTRACT Gruber, L., Steinwender, R., Krimberger, K. and S61kner, J., 1991. Roughage intake of Simmental, Brown Swiss and Holstein Friesian cows fed rations with 0, 25 and 50% concentrates. Livest. Prod. Sci., 27: 123-136. Two short-term feeding trials (3 weeks on each treatment using a total of 54 lactating cows in a 3 X 3 Latin square design were carried out to determine the ad libitum roughage intake of Simmental (SI), Brown Swiss (BS) and Holstein Friesian (HF) cows, respectively. The cows were fed rations with 0, 25 and 50% of dry matter ( D M ) as concentrates, the rest as roughage. The roughage consisted of 31.5% hay, 38.1% grass silage and 30.4% maize silage. St, BS and HF cows consumed 10.7, 11.0 and 12.2 kg DM day ~ roughage, equivalent to 87, 93 and 105 g kg -°'75 bodyweight. For concentrate groups 0, 25 and 50%, roughage intake decreased from 12.8 to 11.7 and 9.4 kg DM day-~. The substitution rate derived from linear regression was 0.36 kg DM kg-~ DM. The milk yield was increased from 14. l to 16.7 and 19.7 kg by feeding concentrates, while milk protein concentration increased from 3.0 to 3.2 and 3.4% and milk fat concentration decreased from 4.3 to 4.2 and 4.1%. The regressions of forage intake (kg DM ) on milk yield (kg energy-standardized milk ( E S M ) ) showed big differences between breeds, but also between concentrate levels. The regression slopes were 0.04, 0.23 and 0.28 for SI, BS and HF cows. Keywords: breeds: concentrate levels: dairy cattle: roughage intake: substitution rate.
INTRODUCTION
The animal's requirement for energy is probably the main controller of feed intake (Wangsness and Muller, 1981; Forbes, 1986). It is therefore not surprising that lactating cows of dairy breeds have often shown higher feed intake compared with lower yielding dual-purpose cows (e.g. Zaugg, 1976; Oldenbroek and van Eldik, 1980). In many of these studies the roughage intake 0301-6226/91/$03.50
© 1991 - - Elsevier Science Publishers B.V
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data are confounded with the concentrate level because of feeding concentrate according to milk production. When given identical rations (Oldenbrock, 1984) or at least the same concentrate level (Korver, 1982) Holstein Friesian cows consumed significantly more roughage than Dutch Friesian COWS.
According to the cattle breeds used in Austria the comparison between Simmental, Brown Swiss and Holstein Friesian cows is interesting. As there is little information in the literature concerning these breeds an experiment was carried out to study the roughage intake of Simmental, Brown Swiss and Holstein Friesian cows on identical rations. MATERIALS AND METHODS
Experimental design Two identical feeding trials ( 1986 and 1987 ) were carried out at the experimental farm of the institute using a 3 X 3 Latin square design within each breed. The treatments were three concentrate levels (0, 25 and 50% of total DM intake ). One dual-purpose (Simmental, SI ) and two dairy breeds (Brown Swiss, BS and Holstein Friesian, HF) were investigated. Within each breed nine animals were used every year and they represented three stages of lactation (early, m e d i u m and late), consisting of three animals each. The experimental design is shown in Table 1. Each period lasted for 3 weeks; the results, however, were only calculated from the last 2 weeks of each period.
Test animals The cows used in the trials are characterized in Table 2. As usual in Austria, cows of dairy breeds (BS and HF) originated from US pedigree sires. In the case of the dual-purpose Simmental breed, the cows represented the native herd. The SI, BS and HF cows are descended from nine, seven and eight different sires, respectively. At the onset of the experiment the three breeds differed distinctly in liveweight and milk yield, but there were no important differences in age and stage of lactation. Eight of 27 animals from the first year were used in the second experiment.
Measurements, sampling and analyses' Individual feed intake and milk yield were recorded each day throughout the experiment. The composition of the milk (fat, protein and lactose) was analysed from each milking (0400 h and 1600 h) by near-infrared spectroscopy (Milko scan 93, FOSS Electric). Samples of the different feeding stuffs were taken each morning to determine the DM content by oven drying ( 105 °C, 24 h). The samples were bulked for 1 week to analyse the content of the Weende crude nutrients and minerals. The digestibility and energy concentration were determined by the in vitro gas production method (Menke
125
ROUGHAGE INTAKE OF COWS FED CONCENTRATES
TABLE 1
The experimental design Breed Simmental (SI)
Brown Swiss ( BS )
Holstein Friesian ( HF )
Cow nos. Cow nos. Cow nos. Cow nos. Cow nos. Cow nos. Cow nos. Cow nos. Cow nos. 1,2,3 ~ 4,5,6 7,8,9 1,2,3 4,5,6 7,8,9 1,2,3 4,5,6 7,8,9
Period 1 SI 02 Period2 S125 Period3 S150
SI 252 SI50 SI 0
SI 502 SI 0 SI25
BS 0 BS25 BS50
BS 25 BS50 BS 0
BS 50 BS 0 BS25
HF 0 HF25 HF50
HF 25 HF50 HF 0
HF 50 HF 0 HF25
LCow n u m b e r 1,4,7: early stage of lactation; cow n u m b e r 2,5,8: medium stage of lactation: cow n u m b e r 3,6,9: late stage of lactation. -'Concentrate level: 0, 25 and 50% of total DM intake, respectively, i.e. SI 25 indicates Simmental cows
given concentrates at 25% of total DM intake. TABLE2 Some characteristics of the test cows in the preliminary period ( n = 18 )
Traits
S1
BS
HF
Liveweight ~ (kg) Milkyield(kgESM) 2 Age ( d a y s ) Parity
641 _+ 13 15.7 + 1.2 1661 _+58 2.67"+ 0.20
574 + 15 15.3 + 1.1 1397 _+89 1.72"+ 0.21
567 _+ 12 20.9 _+ 1.2 1438 _+86 1.94_+ 0.21
Stage of lactation Early ( d a y s )
Medium ( d a y s ) Late ( d a y s )
65 144 236
_+ 16 _+ 9 _+ 16
85 178 254
_+ 9 "+17 "+ 14
65 113 199
-+ 13 "+10 ± 16
~Mean of eight measurements during the experiments. 2ESM = e n e r g y - s t a n d a r d i z e d milk ( 3.14 MJ k g - t ) according to Bickel ( 1988 ).
and Steingal3, 1988 ) in the first year. In the second year in vivo digestibility trials using four wethers for each single feedingstuff were conducted according to van Es and van der Meer (1980). The liveweights were recorded on two consecutive days at the beginning of each period and at the end of the third period. Body measurements were taken once in the middle of each period.
Feeds and feeding The roughage consisted of equal parts ( D M ) of hay, grass silage and maize silage and was offered at each meal (0330-0730 h and 1430-1830 h ) as single feedstuffs ad libitum ( 5-10% refusals ), not as a mixed ration. The ration was computed every other day taking in consideration the previous feed intake of the period. Within each meal the sequence of feeding was: 50% of concentrates, grass silage, maize silage, 50% of concentrates, hay. The concentrate
126
L. GRUBER ETAL.
TABLE 3 Content o f crude nutrients, minerals, digestibility and energy concentration of the feedingstuffs used in both years (in DM, mean o f six analyses) Feedingstuff Year
DM l (%)
XP: (g)
XL 2 (g)
XF 2 (g)
XA 2 (g)
Ca 3 (g)
p3 (g)
DOM 4 (%)
Hay
1 2
86.5 86.9
104 120
2t 23
284 305
83 92
6.8 7.4
3.3 3.6
66.1 65.7
Grass silage
1 2
44.4 24.0
143 156
33 41
299 308
112 135
8.7 9.5
3.7 4.4
Maize silage
1 2
23.4 25.6
83 83
25 29
305 226
54 63
3.6 3.7
Concentrate
1 2
87.0 86.6
171 184
25 23
45 45
50 53
8.5 9.0
ME 5 (MJ)
NEL 5 (MJ)
NEF 5 (MJ)
9.20 9.05
5.43 5.29
5.15
68.8 64.9
9.45 8.60
5.60 4.98
5.10
2.3 2.8
64.2 70.0
9.28 10.57
5.50 6.39
6.00
5.4 5.7
85.2 81.4
13.17 12.39
8.30 7.78
6.68
DM = dry matter. zXP, XL, XF, XA = c r u d e protein, fat, fibre, ash, respectively. 3Ca, P = c a l c i u m , phosphorus. 4DOM = digestibility o f organic matter. 5ME, NEL, N E F = metabolizable energy, net energy lactation, net energy fat (G.D.R.).
was composed of 48.5% barley, 30% maize, 18% soybean meal and 3.5% mineral/trace element mix. The chemical composition and energy concentration of the feedingstuffs used is shown in Table 3. The quality was similar in both years, with the exception of DM content of the grass silage and energy concentration of maize silage. Both hay and grass silage were cut in a rather late stage of vegetation.
Statistical analyses The data were analysed by the " m i x e d model least-squares and m a x i m u m likelihood" computer programme (Harvey, 1985) supposing the following model: Yi-o where Yi-o /t bi
Pk S/
Ym Cn
(be)in ei_o
= lt+ bi+ao+pk + st+ ym+Cn+ ( bc)in+e~-o = observed value of the various traits, = least squares mean, = f i x e d effect o f i t h breed, i = 1,2,3, = r a n d o m effect o f j t h animal within ith b r e e d , j = 1,2 ..... 46, = fixed effect of kth parity, k = 1,2,3, = fixed effect o f lth stage of lactation, l = 1,2,3, = fixed effect o f ruth year, m = 1,2 = fixed effect o f nth concentrate level, n = 1,2,3, = interaction between ith breed and nth concentrate level, = error term.
ROUGHAGE INTAKE OF COWS FED CONCENTRATES
127
The pairwise comparisons of groups were computed according to the Bonferroni-Holm test (EB1, 1987 ). The data are presented as least-square means together with the row-pooled standard error (SE) within groups. Within each treatment row, values with different superscripts are significantly different from each other ( P < 0.05 ). Different regression calculations presented in this paper were based on the same model.
RESULTS
Feed intake The feed intake data in Table 4 show highly significant differences between the three concentrate and the three breed groups. The total DM intake increased linearly from 12.8 to 18.5 kg by adding concentrate to the roughage diet while the roughage intake decreased from 12.8 to 9.4 kg DM. The mean substitution rate over all breeds derived from linear regression analysis was 0.36 kg roughage DM k g - ' concentrate DM, with 0.37, 0.38 and 0.34 for SI, BS and HF cows, respectively. The differences in substitution rate between breeds were not significant. The regression of roughage (and total) intake on concentrate intake was linear and not quadratic. The energy supply was increased from 72 to 125 MJ net energy lactation(NEL) day- 1, corresponding to 5.9 MJ NEL kg- 1 DM concentrate. The animals consumed 2.1,2.8 and 3.5 times their maintenance requirement (293 kJ NEL kg BW-°-75; GEH, 1986) in concentrate levels of 0, 25 and 50%. There were significant interactions in energy supply (metabolizable energy (ME), NEL ) between concentrate level and breed. The HF cows improved their energy intake by feeding concentrates to a higher degree than BS or SI cows. The HF cows had a significantly higher feed intake capacity than the two TABL E 4 Daily feed intake Traits
Roughage (kg D M ) Concentrate (kgDM)*** Total ( k g D M ) Energy ( M J ME)*** Energy (MJ NEL)*** Energy b a l a n c e ~ (MJ N E L ) * * F e e d i n g level 2.**
C o n c e n t r a t e level (%)
Breed
SE
0
25
50
S!
BS
HF
12.84 a 0.00 a 12.84" 122-03 a 72.12 ~ -6.63 ~ 2.06"
I 1.71 b 3.90 b 15.62 b 159.67 b 96.27 b 9.63 b 2.76 b
9.37 c 9.16 c 18.53 c 204.74 c 125.45 c 28.69 c 3.54 c
10.74 a 4.08" 14.82 a 153.96 a 92.95" 15.24 a 2.54 a
11.00 a 4.21 ~ 15.21 a 157.20 ~ 94.98 ~ 10.29 ~b 2.72 b
12.20 b 4.76 b 16.96 b 175.28 b 105.91 b 6.15 b 3.10 c
**,***Interaction ( c o n c e n t r a t e × breed ) on a P < 0.01, P < 0.001 level, respectively, ~Calculated from energy i n t a k e m i n u s energy r e q u i r e m e n t ( G E H , 1986 ). 2Multiple of m a i n t e n a n c e r e q u i r e m e n t (energy i n t a k e / m a i n t e n a n c e r e q u i r e m e n t ; G E H , 1986 ).
0.91 0.61 1.08 9.50 5.80 5.58 0.15
128
L. GRUBER ET AL
160]
z
-4
A
o
,
E
~
~
100-
v
80-
~
60-
•~
40-
20 O.
SI 0
BS 0
HF 0
SI 25
BS 25
HF 25
SI 50
BS 50
HF 50
Fig. 1. Roughage and total feed intake related to metabolic bodyweight o f cows at different concentrate levels.
other breeds, which did not differ significantly from each other. Expressing feed intake per unit metabolic bodyweight the proportional differences became greater because of the higher weight of the SI cows (Fig. 1 ). Given the all-roughage ration the HF cows consumed 18% more than SI cows. Feeding a ration with 50% concentrate, they were superior by 25%.
Ration characteristics In Table 5 it can be seen that the average roughage ration consisted of 31.5% hay, 38.1% grass silage and 30.4% maize silage. The proportion of concentrate (0, 25.0 and 49.4%) also corresponded well to the experimental plan. The small deviations in the roughage proportions are caused by the fact that some animals preferred grass silage. The DM content of the total ration increased and crude fibre content decreased as a consequence of increasing concentrate levels. The protein content rose from 11.7 to 14.7%, and the energy concentration from 9.4 to 11.0 MJ ME. Therefore the protein/energy ratio of almost 13 was similar in all concentrate levels.
Milk yield and composition The mean actual and energy-standardized milk (ESM) yield differed significantly between the breeds ( P < 0.001 ). The daily ESM yield amounted to
129
ROUGHAGE INTAKE OF COWS FED CONCENTRATES T ABLE 5
Composition and characteristics of the ration Traits
Hay (% o f roughage D M ) Grass silage (% of roughage DM ) Maize silage (% of roughage DM ) Concentrate (% of total D M ) DM content (%) XP content ( g k g -~ D M ) XFcontent (gkg -t DM) ME c o n t e n t ( M J kg -~ D M ) Protein/energy (g XP MJ -~ M E )
Concentrate level (% )
Breed
0
25
50
SI
31.8 37.9 30.2 0" 36.3 a 117 a 289 a 9.37 a 12.5 ~
31.0 38.0 31.0 25.0 b 42.0 b 132 b 227 b 10.23 b 12.9 b
31.5 30.9 ab 38.4 38.5 30.1 30.5 49.4 c 24.7 50.4 c 42.8" 147 c 132 168 c 228 11.04 ~ 10.21 13.3 c 12.9
SE BS
HF
33.1 b 37.4 29.5 24.8 43.6 b 132 228 10.22 12.9
30.4 a 38.3 31.3 24.9 42.3 ~ 132 228 10.21 12.9
2.4 3.5 1.9 1.6 1.4 3 7 0.18 0.3
TABLE 6
Daily milk yield and composition Traits
Milk yield (kg)*** Fat content (%)** Protein content (%)*** Lactose content (%) Milk yield (kg ESM)***
Concentrate level (% )
Breed
SE
0
25
50
SI
BS
HF
13.88 a 4.32 a 3.04 a 4.81 14.09 a
16.56 b 4.17 b 3.18 b 4.80 16.67 b
19.44 c 4.11 b 3.39 c 4.85 19.70 ~
13.16 a 4.11 3.41 ~ 4.83 13.36 a
15.69 b 4.24 3.21 a 4.83 15.95 b
21.03 " 4.25 2.98 b 4.80 21.09'
1.28 0.18 0.14 0.12 1.43
**,***Interaction (concentrate X breed ) on a P < 0.01, P < 0.001 level, respectively.
13.4, 16.0 and 21.1 kg for the SI, BS and HF cows (Table 6 ). There were only small differences in the concentration of milk fat. In milk protein concentration, however, the HF cows reached a value of only 2.98%, compared to 3.21 and 3.48% for the BS and SI cows. By feeding concentrates the mean milk yield over all breeds increased from 14.1 to 19.7 kg ESM (Table 6 ). The influence of both energy supply and concentrate level on milk protein and fat concentration is clearly demonstrated and presumably reflects previously demonstrated physiological relationships: milk protein concentration is increased from 3.0 to 3.4% presumably due to improved microbial protein synthesis (energy supply) and milk fat concentration is reduced from 4.3 to 4.1% presumably due to the narrower acetic/ propionic acid ratio caused by an increased concentrate proportion. Significant interactions between concentrate level and breed for milk production traits were detected as clearly demonstrated in Figs. 2 and 3. The actual milk yield was improved by adding concentrates to the ration in Hol-
130
L. GRUBER
ET
,
•
AL
25
20
o~
7
• " oO
•"
o c'q
LI~ C'q
J
15
v
10 -,e m
0
f
SI 0
BS 0
HF 0
SI 25
BS 25
HF 25
SI 50
BS 50
HF 50
Fig. 2. Theoretical milk yield (ESM) from roughage and actual milk yield (ESM) of cows at different concentrate levels.
4.5-
4
5.5J
)'x
c
2
g
3-
c
2.5c
'6 ka_
1.5
SI 0
SI 25
SI 50
BS 0
BS 25
BS 50
HF 0
Fig. 3. Fat and protein content of milk at different concentrate levels.
HF 25
HF 50
131
ROUGHAGE INTAKE OF COWS FED CONCENTRATES TABLE 7 kiveweight and body m e a s u r e m e n t s Traits
Liveweight (kg) Liveweight change (g d a y - ' ) W i t h e r height ( c m ) Body length ( c m ) Chest girth ( c m ) D e p t h o f chest ( c m )
C o n c e n t r a t e level (%)
Breed
SE
0
25
50
SI
BS
HF
592.2 a - 370 a 133.9 166.2 193.4 72.2
590.1 a 717 b 133.8 166.4 193.4 72.4
601.5 b 525 b 134,2 166,3 194,4 72.5
625.2" 347 131.8 a 164.0" 196.3 71.9
588.3 ab 330 134.3 ab 166.4 ab 192.4 72.4
570.3 b 194 135.8 b 168.4" 192.4 72.8
15.4 710 1.0 1.7 2.0 1.1
stein cows to a much higher extent (from 17.3 to 25.1 kg ESM) than in Simmental cows (from 11.8 to 14.7 kg ESM). The Brown Swiss were intermediate (Fig. 2 ). The theoretical milk yield from the roughage was depressed by concentrate level from 11.7 to 5.2 kg ESM. The protein concentration in milk of HF cows was extraordinarily low (2.77%) in the all-roughage group presumably due to the marked energy deficit on this ration. The high fat concentration of this group (4.49%) could be caused partly by a high fat mobilization. At the high concentrate level the differences in milk composition between breeds were not as large as in the roughage group (Fig. 3 ).
Body measurements The data concerning the body measurements are presented in Table 7. The average liveweights for SI, BS and HF cows were 625, 588 and 570 kg. According to the milking potential SI cows gained more weight than BS and HF cows. The dairy cows (BS and H F ) were higher and longer whereas SI cows showed a higher chest girth. The influence of concentrate level can be seen more or less in the liveweights with a tendency of higher weights at higher concentrate levels and also by a substantial loss of liveweight in the roughage group, whereas the animals gained weight when fed concentrate. No interactions occurred between concentrate level and breed. DISCUSSION AND CONCLUSIONS
Breeds Across rations in the present study Brown Swiss and Holstein cows consumed by 6 and 20% more roughage than Simmental cows k g - ' metabolic bodyweight. This is in line with Swiss investigations of Zaugg (1976) and Bieri ( 1982 ). On the other hand some German authors using Simmental and Red Holstein cows found only slight differences (Pallauf and KirchgeBner, 1976; Lindermayer, 1986). Hafez et al. (1989) found a superiority of HF
132
L.GRUBERETAL.
over Red and White cows of 6% in roughage intake related to metabolic bodyweight. Comparing Dutch Friesian with HF cows Oldenbroek (1979) and Oldenbroek and van Eldik (1980) found minor differences of 7 and 2%, respectively. In all these cases roughage intake is confounded with concentrate level by feeding concentrate according to milk yield. Feeding identical rations (all roughage or equal concentrate portion) HF cows consumed 5% (Rohr, 1972) and 4% (Oldenbroek, 1984) more than German and Dutch Friesian cows. Korver ( 1982 ) found hardly any difference under similar situations. It can be concluded that the superiority of Holsteins for roughage intake of 20% in the present study lies in the upper range of literature data, and that Holstein cows are clearly able to consume more than Brown Swiss. However, to make the results comparable, identical rations should be fed to all types of cows and intake should be related to metabolic bodyweight.The differences in roughage intake between Simmental and HF cows in the present study are larger than between Black and White and HF cows in other studies. Across breeds, higher feed intake is accompanied by higher milk yield in all the abovementioned publications.
Concentrate level From the recent and comprehensive review of Kleinmans and Potthast (1984) it can be concluded that - apart from factors related to the animal the quality of roughage and the proportion of concentrate are the most important determinants of roughage intake. There is also clear evidence that the substitution rate increases progressively with increasing amounts of concentrate (Ostergaard, 1979; Schwarz and KirchgeBner, 1985; Gruber, 1988 ). In the present study, however, no curvilinearity could be detected. This is in agreement with the results of Ward and Kelley (1969) and Kristensen and Norgaard (1987), when feeding hay and grass silage as the only roughage. The physiological reason for this linear decrease of roughage intake could lie in the feeding strategy of giving the concentrate in two separate doses (Kaufmann, 1976) and that the total concentrate proportion did not exceed 50%. A third possible reason is that concentrate and roughage intake (within one concentrate level) are positively correlated because of the experimental plan of feeding concentrate not as a fixed amount but as a certain percentage of the diet. But when concentrate level is expressed as a percentage of total DM intake (C%), roughage intake (RI, kg DM) could be best described by the following quadratic regression equation: R I = 11.68-0.071 X ( C % - 2 5 ) - 0 . 0 0 1 0 3 X ( C % - 2 5 ) 2 C V = 10.2, R2=0.71 It was not intended that this experiment should study the effect of concentrate on milk yield. However, the results with regard to differences between
ROUGHAGE INTAKE OF COWS FED CONCENTRATES
I33
breeds are interesting. Regressions of yield on concentrate intake were linear rather than curvilinear and - across the breeds - the milk yield increased by 0.63 kg ESM kg- 1 DM concentrate. There were, however, significant differences ( P < 0 . 0 5 ) between breeds with linear regression coefficients of 0.36, 0.73 and 0.81 for breeds SI, BS and HF. That means that dairy breeds converted the additionally offered energy into milk production to a much larger extent whereas dual-purpose cows gained bodyweight. It should be kept in mind that the effect of concentrate level on milk yield in the present study may be partly influenced by carry-over effects and by the short duration of the experiment. Concerning the effect of concentrate on roughage intake it can be concluded that a mean substitution rate of 0.36 determined in the present study is typical of this concentrate level (up to 50% of total ration) in connection with the m e d i u m quality of roughage (9.4 MJ ME kg -1 DM). The low efficiency of concentrate with regard to milk yield (0.63) is a consequence of the experimental plan of feeding concentrate not according to milk yield so that the energy supply exceeded the yield achieved especially in the dual-purpose breed (SI).
Milk yield-feed intake correlation The regressions of roughage and total feed intake on milk yield showed big differences between breeds, but also between concentrate levels (Fig. 4). Over all rations, SI, BS and HF cows increased their total feed intake by 0.09, 0.31 and 0.37 kg DM and their roughage intake by 0.04, 0.23 and 0.28 kg DM kgincrease in ESM, respectively. From Fig. 4 it is easily seen that the slopes for roughage intake are typically higher both for the all-roughage rations and for the dairy breeds. These are situations where energy deficit is likely to be substantial and animals try to compensate for their energy deficit. In groups SI 0, BS 0 and HF 0 the cows consumed 101, 92 and 79% of their energy requirements (based on recommandations of GEH, 1986). In contrast the cows fed 50% concentrate were over-supplied ( 192, 154 and 132%). Lindner et al. ( 1981 ) found significant correlations of feed intake on milk yield only for first lactating but not for older cows with rations of 25% concentrate. On average, however, the older cows were over-supplied in energy corresponding to 3.5 kg FCM. On the other hand Journet and R e m o n d (1976) found clear positive relationships between milk yield and feed intake when offering all roughage diets (grass or maize silage). It can be concluded that cows try to compensate for a substantial energy deficit by increasing both their total feed and their roughage intake. A possible reason for the different regression slopes between the dual-purpose group and the dairy groups may lie in different mechanisms of partitioning the nutrients. Dual-purpose cows tend to use nutrients to gain bodyweight to a higher degree than dairy cows. Low-yielding dual-purpose cows probably
134
L. G R U B E R
BROWN SWISS
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eat the same amount of feed as the high yielders because they use the excess nutrients for bodyweight gain. When the requirement for bodyweight gain is taken into account additionally to the requirement for milk production, the results of this study are in line with the hypothesis that energy balance regulation is the main drive for feed intake (Wangsness and Muller, 1981; Forbes, 1986).
REFERENCES Bickel, H., 1988. Fat-corrected milk (FCM), an inaccurate and confusing term. Livest. Prod. Sci., 18: 311-313. Bieri, P., 1982. Produktionstechnische und wirtschaftliche Untersuchungen fiber den Futteraufwand bei Milchkfihen w~ihrend der Laktation. Diss. ETH Nr. 7140, Ztirich, 190 pp. EBI, A., 1987. Statistische Methoden in der Tierproduktion. Verlagsunion Agrar, Wien, 104 pp. Forbes, J.M., 1986. The Voluntary Food Intake of Farm Animals. Butterworths, London, p. 3. GEH (Gesellschaft ffir Ern~ihrungsphysiologie der Haustiere, Ausschuss f'fir Bedarfsnormen), 1986. Energie- und Nahrstoffbedarf landwirtschaftlicher Nutztiere, Nr. 3: Milchkfihe und Aufzuchtrinder. DLG-Verlag, Frankfurt (Main), 13 pp. Gruber, L., 1988. Grundfutteraufnahme bei Rindern: Fiitterungsaspekte. Symposium "Produktion von Milch und Rindfleisch auf der Basis von wirtschaftseigenem Futter", Leipzig 17 March, Polycopy Gumpenstein, 25 pp.
ROUGHAGE INTAKE OF COWS FED CONCENTRATES
l 35
Hafez, S., Junge, W., Hagemeister, H. and Kalm, E., 1989. Futteraufnahme und Futterverwertung der Rassen Rotbunt, Schwarzbunt und Red-Holstein × Rotbunt unter Laufstallbedingungen. Zfichtungskunde, 61:41-54. Harvey, W.R., 1985. User's guide to LSMLMW. Mixed model least-squares and maximum likelihood computer program. Polycopy Ohio State University. Journet, M. and Remond, B., 1976. Physiological factors affecting the voluntary intake of feed by cows: A review. Livest. Prod. Sci., 3: 129-146. Kaufmann, W., 1976. Influence of the composition of the ration and the feeding frequency on pH-regulation in the rumen and on feed intake in ruminants. Livest. Prod. Sci., 3:103-114. Kleinmans, J. and Potthast, V., 1984. Zur "Verdrgngung" von Grundfutter dutch Kraftfutter in der Milchviehffitterung. Obers. Tierern~ihrung, 12:165-186. Korver, S., 1982. Feed intake and production in dairy breeds dependent on the ration. Diss. Wageningen, 139 pp. Kristensen, V.F. and Norgaard, P., 1987. Effect of roughage quality and physical structure of the diet on feed intake and milk yield of the dairy cow. Research in Cattle Production Danish Status and Perspectives. Det kgl. danske Landhusholdningsselskab, pp. 79-91. Lindermayer, H.. 1986. Futteraufnahme, Futterverwertung und Wirtschaftlichkeit von Doppelnutzungsrasse und Milchrasse fiber die Dauer einer ganzen Zwischenkalbezeit. Diss. TU Miinchen-Weihenstephan, 184 pp. Lindner, H.P., Kirchgel3ner, M. and Schwarz, F., 1981. Zur Futteraufnahme von Kfihen in Abhi~ngigkeit v o n d e r Milchleistung. Ziichtungskunde, 53: 99-112. Menke, K.H. and Steingag, H., 1988. Estimation of the energetic feed value obtained from chemical analysis and in vitro gas production using rumen fluid. Anim. Res. Dev., 28: 7-55. Oldenbroek, J.K., 1979. Differences in the intake of roughage between cows of three breeds fed two levels of concentrates according to milk yield. Livest. Prod. Sci., 6: 147-151. Oldenbroek, J.K., 1984. Holstein Friesians, Dutch Friesians and Dutch Red and Whites on two complete diets with a different amount of roughage: Performance in first lactation. Livest. Prod. Sci., 11 : 401-415. Oldenbroek, J.K. and van Eldik, P., 1980. Differences in feed intake between Holstein Friesian. Dutch Red and White and Dutch Friesian Cattle. Livest. Prod. Sci., 7:13-23. Ostergaard, V., 1979. Strategies for concentrate feeding to attain optimum feeding level in high yielding dairy cows. 482. Beretning Statens Husdyrbrugs Forsog, Kobenhavn, 138 pp. Pallauf, J. and Kirchgel3ner, M., 1977. Zur Grundfutteraufnahme von Milchkiihen der Rasse Deutsches Fleckvieh und Red Holstein Frisian-Kreuzungen. Zfichtungskunde, 19:120-137. Rohr, K., 1972. Untersuchungen fiber die Futteraufnahme und Futterverwertung bei Milchkfihen verschiedener Rassen unter besonderer Bedicksichtigung des Grfinfutters. Kiel. Milchwirtsch. Forschungsber., 24: 23-96. Schwarz, F.J. and Kirchgel3ner, M., 1985. Grundfutteraufnahme von Milchkiihen in Abhi~ngigkeit von Lebendgewicht, Zahl der Laktationen, Krafffutterzufuhr und Grundfutterqualit~it. Ziichtungskunde, 57: 267-277. Van Es, A.J.H. and van der Meer, J.M., 1980. Methods of analysis for predicting the energy and protein value of feeds for farm animals. Workshop on methodology of analysis of feeding stuffs for ruminants, Lelystad, NL, 27-29 May, 106 pp. Wangsness, P.J. and Muller, L.D., 1981. Maximum forage intake for dairy cows. Review. J. Dairy Sci., 64: 1-23. Ward, G.M. and Kelley, P.L., 1969. Influence of roughage-to-concentrate ratios on ad libitum consumption by lactating cows. J. Dairy Sci., 52:1017-1019. Zaugg, U., 1976. Vergleichsversuch mit Braunvieh, Simmentaler Fleckvieh und Holstein Friesian amerikanischer Herkunft. Diss. ETH Nr. 5671, Zfirich, 121 pp.
136
L GRUBERETAL.
RESUME Gruber, L., Steinwender, R., Krimberger, K. et S61kner, J., 1991. Consommation de fourrages par les vaches Simmental, Brown Swiss et Holstein Friesian recevant des rations contenant 0%, 25% et 50% de concentres. Livest. Prod. Sci., 27: 123-136 (en anglais). Pour mesurer la consommation ad libitum de fourrages par des vaches Simmental (SI), Brown Swiss (BS) et Holstein Friesian (HF), on effectu6 deux essais d'alimentation en cart6 latin (3X3) de courte dur6e (3 semaines par traitement) sur un total de 54 vaches. Les rations comportaient 0%, 25% ou 50% de la MS sous forme de concentr6s et le fourrage 6tail un m61ange de 31,5% de foin, 38,1% d'herbe et 30,4% d'ensilage de ma'fs. Les vaches SI, BS et HF ont consomm6 respectivement 10,7:11,0 et 12,2 kg de MS de fourrages par jour soit 87, 93 et 105 g par kg de poids m6tabolique (po.vs). La consommation de fourrage a 6t6 de 12,8; 11,7 et 9,4 kg de MS par jour avec les rations conlenant respectivement 0%, 25% el 50% de concentr6s, le taux de substitution calcule par regression lineaire 6tan! de 0,36. La production laitibre ( 14,1; 16,7 el 19,7 kg par jour) et la teneur en proteines du lair (3,0:3,2 et 3,4%) ont augment6 avecla proportion de concentr6 landis que le taux butyreux diminuait (4,3; 4,2 el 4,1%). Les coefficients de r6gression de la quanlil6 de fourrage consomme (kg de MS par jour) par rapport ~ la production laitibre (kg par jour) onl differ6 avec la race (0,04:0,23 et 0,28 pour les vaches SI, BS et HF) et aussi avec la proportion de concentr6. KU RZFASSUNG Gruber, L., Steinwender, R., Krimberger, K. und S61kner, J., 1991. Grundfutteraufnahme von Fleckvieh, Brown Swiss und Holstein Friesian Kiihen bei Rationen mit 0, 25 und 50% Kraftfutter. Livest. Prod. Sci., 27:123-136 (aufenglisch). In einer Versuchsanlage nach dem lateinischen Quadrat wurden zwei kurzffistige Fiitterungsversuche (3 Wochen je Behandlung) mit insgesamt 54 laktierenden Kfihen durchgef'tihrt, um die ad libitum Grundfutteraufnahme der Rassen Fleckvieh (SI), Brown Swiss (BS) bzw. Holstein Friesian (HF) festzustellen. Die Kfihe erhielten Rationen mit 0, 25 bzw. 50% der Trockenmasseaufnahme als Kraflfutter, das Grundfutter bestand aus 31,5% Heu, 38,1% Gras- und 30,4% Maissilage. Die t~gliche Grundfutteraufnahme der SI, BS bzw. HF Kfihe betrug 10,7, 11,0 bzw. 12,2 kg TM, pro kg metabolischem K6rpergewicht 87, 93 bzw. 105 g. In den Kraftfutterstufen 0, 25 und 50% ging die Grundfutteraufnahme von 12,8 auf 11,7 und 9,8 kg TM zurfick. Die Grundfutterverdr~ingung, abgeleitet mit Hilfe einer linearen Regression, ergab einen Weft von 0,36 kg TM kg -~ TM. Durch das Kraftfutter wurde die Milchleistung von 14,1 auf 16,7 bzw. 19,7 kg gesteigert, ebenso der Gehalt an MilcheiweiB yon 3,0 auf 3,2 bzw. 3,4%. Doch der Milchfettgehalt sank von 4,3 auf4,2 bzw. 4,1%. Die Regressionen zwischen Grundfutteraufnahme (kg TM) und Milchleistung (kg ESM) zeigten groBe Unterschiede zwischen den Rassen, jedoch auch zwischen den Kraftfutterstufen. Die Regressionskoeffizienten betrugen 0,04, 0,23 und 0,28 f'tir SI, BS und HF Kfihe.