Milk production on grass silage and cereals only

Transcription

1 Milk production on grass silage and cereals only Fodringsdagen, Herning 2016 Rolf Spörndly Swedish University of Agricultural Sciences Uppsala, Sweden

2 Silage and cereals only is that an interesting option? Eva and Rolf Spörndly

3 Why?

4 Aim The aim was to evaluate the effect on milk yield of excluding protein-rich concentrate supplements from the diet.

5 Methods Four treatments were compared. Silage170 + cereals and protein concentrate Silage170 + cereals Silage130 + cereals and protein concentrate Silage130 + cereals The higher protein content in Silage 170 was due to inclusion of 1/3 red clover 37 SRB cows for 20 weeks, variable lactation stage

6 Feed analysis Table 1 Composition of feeds used. Cereals consisted of 36% barley, 34% wheat and 25% oats. Protein concentrate consisted of soy expeller 47%, rapes seed cake 16%, oats 15%, rapeseed 11%. Item 1 Cereals Protein concentrate Silage170 Silage130 DM, % 89.4 (1.50) 92.0 (1.79) 35.0 (1.20) 36.4 (1.76) ME, MJ/ kg DM (0.21) 11.6 (0.11) AAT, g/kg DM PBV, g/kg DM CP, g kg DM 125 (17.7) 328 (6.2) 169 (4.3) 132 (3.7) EE, g/kg DM NA NA Ash, g/kg DM, 58 (2.0) 76 (3.4) 86 (4.7) 75 (5.9) Starch, g/kg DM NA NA NDF, g/kg DM (19.9) 471 (13.9)

7 Production results Effect of concentrate N=37 Effect of silage N=37 Cereals/conc Cereals Sign 1 Silage170 Silage130 Sign 1 Kg milk 35.7 (0.97) 30.0 (1.00) *** 32.9 (0.96) 32.8 (0.99) NS Kg ECM 35.3 (0.86) 30.9 (0.89) ** 33.6 (0.85) 32.7 (0.87) NS Fat, % 4.01 (0.10) 4.40 (0.10) ** 4.21 (0.10) 4.21 (0.10) NS Protein, % 3.16 (0.05) 3.25 (0.05) NS 3.24 (0.05) 3.17 (0.05) NS Lactose, % 4.80 (0.02) 4.77 (0.02) NS 4.80 (0.02) 4.77 (0.02) NS Cell counts, log 1.57 (0.10) 1.61 (0.11) NS 1.55 (0.10) 1.63 (0.11) NS LWG, kg 36.8 (7.02) 25.2 (7.02) NS 40.6 (7.02) 21.4 (7.02) Tend BCS 0.28 (0.148) 0.34(0.125) NS 0.30 (0.128) 0.31 (0.145) NS N efficiency 2, % 28,0 (1,14) 33,6 (1,17) ** 30,6 (1,14) 31,0 (1,17) NS

8 Intake data 17,4 cp in tot DM 15,9 % cp in tot DM Effect of concentrate N=37 Effect of silage N=37 Intake per day Cereals/conc Cereals Sign 1 Silage170 Silage130 Sign 1 Silage, kg DM 15.8 (0.58) 14.4 (0.58) NS 13.8 (0.57) 16.4 (0.57) (**) 2 Cereals, kg 1.9 (0.47) 7.1 (0.48) *** 4.8 (0.47) 4.2 (0.48) NS Protein conc, kg 4.0 (0.29) 0.0 (0.30) *** 2.0 (0.29) 1.9 (0.30) NS Totalt, kg DM 21.2 (0.74) 20.4 (0.74) NS 19.7 (0.73) 22.0 (0.74) NS Energi, MJ 257 (9.7) 246 (10.0) NS 239 (9.7) 264 (10.0) Tend AAT, g 1854 (72.7) 1572 (74.6) * 1641 (72.7) 1788 (74.6) NS PBV, g 777 (37.4) 514 (38.4) *** 876 (37.4) 415 (38.4) *** Crude protein, g 3887 (153.0) 3096 (157.1) ** 3588 (153.0) 3396 (157.1) NS NDF, g 7943 (256.8) 7642 (263.7) NS 6874 (256.8) 8710 (263.7) *** Starch, g 1281 (234.4) 3455 (240.7) *** 2526 (234.4) 2209 (240.7) NS 1) *= p<0.05, **=p<0.01, ***=p< ) NS when intake silage 130 is corrected to 14.6 due to errors

9 Intake data Daily intake Silage cereals N=9 Silage cereals N=9 (cp, % in total DM) (15,5) (13,4) Cereals, kg DM 6,7 (2,25) 6,0 (2,48) Protein conc, kg DM - - Silage, kg DM 13,6 (2,79) 15,3 (2,23) Total, kg DM 20,3 (3,05) 21,3 (3,37) Energy, MJ ME 242 (36,5) 255 (41,4) AAT, g 1549 (234,1) 1625 (264,5) PBV, g 461 (143,2) 52 (102,6) CP, g 3141 (475,4) 2864 (480,9) NDF, g 7019 (1116,2) 8337 (1095) Starch, g 3762 (1258,8) 3346 (1386,5)

10 Conclusions from short mid lactation study Feeding grass/clover silage and cereals only, without protein concentrate, decreased the milk production with about 13 %. Increased silage crude protein content above 130 g per kg DM did not increase milk production when fed with concentrate consisting of cereals only. N-efficiency was 20 % better when feeding the cereals only diet We repeated the experiment the following year, - with only one forage quality (17 cows per group)

11 RESULT Year 2 Cereals +prot Only cereals Diff. Sign. Kg milk 41,4 36,4 5,0 (-12%) *** Kg ECM 40,0 37,3 2,7 (-7%) * Fat content, % 3,8 4,2-0,4 * Prot content % 3,2 3,3-0,1 *

12 Cerals only, optimized in Norfor for 37 kg ECM Cereals only, result evaluated in NorFor Cerals+prot, result evaluated in NorFor Cereals+prot optimized in NorFor för 40 kg ECM

13 The full lactation experiment, first year

14 Aims To investigate whether high producing dairy cows can be fed with a low protein diet based solely on cereals and silage without any reductions in production levels and with a better N-efficiency over a whole lactation Hypothesis: when fed a low CP diet from the onset of lactation the cows would be able to utilize the available protein in the forage and cereal more efficiently resulting in higher N-efficiency and lower N excretion with no reduction in milk yield

15 Material and Methods A two-year study conducted at Lövsta: In total 50 cows included for two lactations ( ) Data and results from 1 st year (Oct 2014 to Oct 2015) of the experiment will be presented

16 Animals and treatments Group 1=Cereal (N=12) Group 2=Cereal + Prot (N=11) (6+6 SRB/SH) SRB: N= 6+7 SH: N= 6+4

17 Feeding Silage fed ad libitum According to KRAV s regulations (Swedish organic) Roughage to concentrate: 50/50 and 60/40 Pasture during summer months (May to August) Individual recording of both concentrates and silage

18 Feed composition Cereal* Prot.* Silage** Pasture** DM, % Energy, MJ/ kg DM CP, g/kg DM AAT, g/kg DM PBV, g/kg DM Fat, g/kg DM NA NA Ash, g/kg DM Starch, g/kg DM NA NA NDF, g/kg DM Am-N, % ph OMD (%)

19 Data sampling Production data, feed intake and LW&BCS for the whole lactation (=10 months) Average daily MY, milk comp., ECM and feed intake as well as LW&BCS calculated for each month Blood and urine sampling for months 1-3 Plasma: Histidine Urine: Creatinine, allantoin and urea Statistical analysis performed in SAS using proc GLM

20 Results Whole lactation yield Group 1: 9760 kg ECM (CP total feed 14.0 %) Group 2: 9706 kg ECM (CP total feed 16.4 %) Swedish average (2015) Organic: 9044 kg ECM Conventional: kg ECM Daily yields: Group 1 MY: 30.5 kg/day and ECM: 31.0 kg/day Group 2 MY: 31.7 kg/day and ECM: 31.2 kg/day In agreement with: In contrast to: Kalscheur et al. (1999) CP: 13.4 vs. 17.0% Korhonen et al (2002) CP: 13.4 vs. 17.0% Colmenero and Broderick (2006): Broderick (2003): 15.1 vs and 18.4% 13.5 vs vs. 16.5% Hym ller et al. (2014): 14 vs. 16% Broderick et al. (2015): 15 vs. 17% Cantalapiedra-Hijar et al. (2014): 12 vs. 16.5% Mutsvangwa et al. (2016): 15 vs. 17% Spek et al. (2013): 11.6 vs. 15.4%

21 Milk Yield by lactation stage Kg/day * * Early Mid Late Lactation stage MY Group 1 MY Group 2 ECM Group 1 ECM Group 2 - Similar observations by Kalcheur et al. (1999): Higher MY in early lactation, but in later stages similar yields between cows receiving low (15%) or high (17%) CP diet.

22 kg/day Milk yield by group and breed ** SH SRB SH SRB Group1 Group2 % 5 4,5 * Fat and Protein by group and breed 4 3,5 * 3 2,5 2 1,5 Fat% Protein% 1 0,5 0 SH SRB SH SRB Group1 Group2

23 Feed intake DMI: Group 1: 22.3 kg Group 2: 22.6 kg Total concentrate intake: Group 1: 7.2 kg Group 2: 9.0 kg Total roughage intake: Group 1: 14.4 kg Group 2: 12.7 kg Korhonen et al. (2002): DMI: Low CP (13.4%): 19.8 kg High CP (17.0%): 19.7 kg Concentrate intake: Low CP: 8.6 kg High CP: 9.2 kg Silage intake: Low CP: 11.2 kg High CP: 10.5 kg

24 Feed intake by lactation stage 30 Kg/day *** 15 *** 10 *** * 5 0 Early Mid Late Lactation stage Total Roughage Group1 Total Roughage Group2 Conc. Group 1 Conc. Group 2 Total DMI Group 1 Total DMI Group 2

25 Nutrient intake vs. microbial protein synthesis Urinary allantoin excretion did not differ between the groups (62.6 vs g/d) Broderick (2003): low CP higher total urinary PD excretion, also increased PD excretion with decreasing NDF content Cantalapriedra-Hijar et al. (2014): similar urinary allantoin for low (12%) and high (16.5%) CP diets BUT increased starch content increased allantoin excretion by 32 mmol/day In this study, starch intake higher in early lactation but overall no differences, NDF intake not obtained

26 Histidine the limiting AA for production? It has been shown that histidine is the limiting AA in cereal and silage based diets (Vanhatalo et al., 1999; Korhonen et al., 2000) Indeed, histidine was lower in group 1 than in group 2 (35.14 vs nmol/ml) in early lactation MY lower in group 1 in early lactation BUT ECM and milk protein yields did not differ Which is in contrast to Vanhatalo et al., 1999; Korhonen et al., 2000 and Cantalapiedra-Hijar et al., 2014) who also reported lower histidine conc. in low CP groups compared to the value obtained in this study (18, 23 and 27.3 nmol/ml, respectively) och fick lägre MY och myik prot yield A good AA balance in the cereal diet + a complementary microbial AA production ensured a sufficient AA supply for milk production

27 N-efficiency Authors Dietary CP, % MUN (mmol/l) Our results 14.0/ /4.27 p<0.001 p<0.05 Korhonen et al. (2002) UUN (g/d) N-efficiency, % 66.1/150.9 p< /32.0 p< / a /9.5 b 103 a /169 b 30.65/27.6* Broderick (2003) 15.1/16.7/ a /4.43 b /5.68 c 119 a /172 b /216 c 30.3 a /27.0 b /23.9 c Reynal and Broderick (2005) Colmenero and Broderick (2006) 17.2/ a /5.68 b 163 a /240 b 30.4 a /29.6 b 13.5/15.0/ a /3.03 b /4.0 c 63 a /91 b /128 c 36.5 a /34.0 b /30.8 c Spek et al. (2013b) 11.6/ a /3.32 b 28 a /74 b 34.9/29.3 Hymøller et al. (2014) 14/ a /3.07 b - 35 a /33 b Cantalapiedra-Hijar et al. (2014) Broderick et al. (2015) 12/ a /131 b 31.3 a /26.4 b 15/ /4.46 b 96 a /161 b 32.1 a /28.8 b

28 3,60 BCS 3,55 3,50 3,45 LW and BCS by lactation month LW (kg) 3, ,35 3,30 3,25 3,20 3,15 3, LW Group 1 LW Group 2 BCS Group 1 BCS Group 2 3, lactation month 620

29 Conclusions A low protein diet (CP=14.1%) based solely on cereal concentrate and high quality silage can be fed to high producing dairy cows without any effects on production levels, and with lower MUN and UUN levels and higher N- efficiency Interesting opportunities and alternatives for (Swedish) dairy farmers Possibility to reduce the negative environmental impact of dairy farming in terms of decreased N-leakage and increased N-utilization However, results from the second year should be waited before drawing the final conclusions Also, implications of the used diet on reproduction and health in the present study will be further addressed