2009 Proceedings of the Cornell Nutrition Conference For Feed ...

More documents

Recommendations

Info

MAXIMIZING MILK COMPONENTS AND METABOLIZABLE PROTEIN UTILIZATION THROUGH AMINO ACID FORMULATION C.G. Schwab 1 and G.N. Foster 2 1 Department of Biological Sciences University of New Hampshire and 2 Central Valley Nutritional Associates, LLC Tulare County, California Heger and Frydrych (1989) concluded, largely from research with non-ruminant animals, that when the essential amino acids (EAA) are absorbed in the profile as required by the animal, the requirements for total EAA is reduced and their efficiency of use for protein synthesis is maximized. Research with lactating dairy cows has been shown many times that increasing predicted concentrations of Lys and Met in metabolizable protein (MP) to recommended levels increases efficiency of use of MP for milk protein synthesis. This should not be a surprising observation in feeding situations where Lys and Met are the first two limiting AA. Therefore, it is reasonable to conclude that maximizing milk components and MP utilization in lactating dairy cows requires providing a profile of AA in MP that matches the profile required for the combined functions of maintenance, reproduction, and milk production, and that the MP is provided in amounts that meets but doesn’t exceed requirements for optimal health, reproduction and milk production. Research to date indicates that of the twenty AA that occur in proteins, only the amount and profile of EAA in MP are of concern. Providing a mixture of nonessential AA (NEAA) to post-weaned dairy calves (Schwab et al., 1982), or lactating dairy cows (Oldham et al., 1979; Schwab et al., 1976; Whyte et al., 2006), where one or more EAA were shown to be limiting, were without benefit. It was also observed that infusing the 10 EAA into the abomasum of lactating cows fed protein deficient diets resulted in increases in yields of milk protein that were similar to the yields that were obtained when casein was infused. Collectively, these observations indicate that when AA supplies approach requirements for total absorbable AA, requirements for total NEAA are met before the requirements for the most limiting EAA. In recognition of these observations, and because Lys and Met had been shown to be the first two limiting EAA for lactating dairy cows fed diets common to North America, NRC (2001) published dose-response plots that related changes in measured percentages and yields of milk protein to model-predicted changes in Lys and Met concentrations in MP. By using a rectilinear model to describe the dose-response relationships, breakpoint estimates for the required concentrations of Lys and Met in MP for maximal content of milk protein were determined to be 7.2 and 2.4%, respectively; corresponding values for maximal protein yield were 7.1 and 2.4%. These were the first estimates ever presented by a Dairy NRC Committee to evaluate a diet for adequacy of AA concentrations in MP, and have proven exceptionally useful for routine users of the NRC (2001) model in their quest to increase milk component yields with similar or lower 1
predicted flows of MP. Because they can be rather easily achieved, target levels for Lys and Met in MP have typically been 6.6 and 2.2%, respectively. Both values approximate 96% of the concentrations needed, according to NRC (2001), for maximal content and yield of milk protein. It is recognized that histidine (His) has been identified as the first limiting AA when grass silage and barley and oat diets are fed, with or without feather meal as a sole or primary source of supplemental RUP (Kim et al., 1999, 2000, 2001a, 2001b; Huhtanen et al., 2002; Korhonen et al., 2000; Vanhatalo et al., 1999). Based on NRC (2001) predicted concentrations of Lys, Met, and His in MP for the diets fed in these experiments, coupled with similar evaluations of diets where cows have (or have not) responded to increased levels of Lys and Met in MP, leads us to speculate that His may become the third limiting AA rather quickly in some diets, particularly where barley and wheat products replace significant amounts of corn in the diet. The purpose of this paper is 3-fold: 1) to share the results of a recent re-evaluation of the Lys and Met dose-response plots using the “final version” of the NRC (2001) model, 2) to share the results of a recent effort to develop the same dose-response plots using CPM-Dairy (v.3.0.10) and AMTS.Cattle (v.2.1.), and 3) to review our approach for maximizing milk components and MP utilization. RECENT RE-EVALUATION OF THE LYS AND MET DOSE-RESPONSE PLOTS USING THE “FINAL VERSION” OF NRC (2001) To determine what the “requirements” for Lys and Met in MP are when the NRC (2001) model is used to evaluate diets, the NRC committee used the indirect doseresponse approach described by Rulquin et al. (1993). This approach has the “unique benefit” of allowing requirement values to be estimated using the same model as that used to predict concentrations of EAA in MP. Because the AA submodel [AA equations (see pages 74-81 in NRC 2001)] had to be developed before the final version of the NRC model was available, a beta version of the model was used to predict the concentrations of Lys and Met in MP in the studies used to develop the dose-response plots. Because of this, and concerned that changes may have been made to the rest of the model, as part of model validation, that may have changed predicted concentrations of Lys and Met in MP, Schwab et al. (2009) reevaluated the Lys and Met dose-response plots using the final version of the model. All steps, as stated in NRC (2001), were repeated. In brief, generating the doseresponse plots involves 5 steps: 1) predicting concentrations of Lys and Met in MP for control and treatment groups in experiments in which postruminal supplies of Lys, Met, or both, were increased and production responses measured, 2) identifying “fixed” concentrations of Lys and Met in MP that are intermediate to the lowest and highest values in the greatest number of Lys and Met experiments, 3) calculating, by linear regression, a “reference production value” for each production parameter in each Lys experiment that corresponds to the “fixed” level of Lys in MP and in each Met 2
Page 1 and 2: 2009 Proceedings of the Cornell Nut
Page 3 and 4: 2009 Cornell Nutrition Conference f
Page 5: Conference Staff, Speakers and Admi
Page 9 and 10: Figure 1. Revised NRC (2001) Lys an
Page 11 and 12: Figure 3. Lys and Met plots for mil
Page 13 and 14: and AMTS.Cattle (v.2.1.1) models (T
Page 15 and 16: MP on increasing the efficiency of
Page 17 and 18: high cows for both years were very
Page 19 and 20: Garthwaite, B. D., C. G. Schwab, an
Page 21 and 22: CHALLENGES OF PREDICTING METABOLIZA
Page 23 and 24: Figure 1. Chemical structure of lys
Page 25 and 26: Table 1. Blocked RUP-Lys and reacti
Page 27 and 28: and in vitro digestibility. However
Page 29 and 30: Table 4. Results from 265 blood mea
Page 31 and 32: ACKNOWLEGEMENTS The data summary of
Page 33 and 34: THE CORNELL NET CARBOHYDRATE AND PR
Page 35 and 36: If this overall value is more appro
Page 37 and 38: mean values for efficiency of use f
Page 39 and 40: efficiency of use of particular AA
Page 41 and 42: Fox, and W. Chalupa.1993. A net car
Page 43 and 44: RECENT RESEARCH WITH LOW-STARCH DIE
Page 45 and 46: Table 1 continued. Dietary content,
Page 47 and 48: Voelker and Allen (2003abc) replace
Page 49 and 50: fermentable starch (3.5%-units) was
Page 51 and 52: monitor the cow’s performance, an
Page 53 and 54: ESTIMATING INTESTINAL DIGESTIBILITY
Page 55 and 56: digestibility within feeds will all
Page 57 and 58:
Table 1. Average in vivo AA and RUP
Page 59 and 60:
presented in Table 3. Crude protein
Page 61 and 62:
human foodstuffs, and originally re
Page 63 and 64:
Novus International. 2008. IDEA. Po
Page 65 and 66:
the present study was to quantify t
Page 67 and 68:
experiments. However, the final wei
Page 69 and 70:
This is surprising in view of the c
Page 71 and 72:
REFINING NITROGEN FEEDING USING CUR
Page 73 and 74:
ecycled urea-N contributed 37.5% of
Page 75 and 76:
observed for DMI nor milk measureme
Page 77 and 78:
procedure described here contains 8
Page 79 and 80:
Table 4. Protozoal predation of bac
Page 81 and 82:
Marini, J. C. and M. S. Attene-Ramo
Page 83 and 84:
of digestion. This involves refinem
Page 85 and 86:
three hours was instead used, as an
Page 87 and 88:
Table 1: Comparison between the non
Page 89 and 90:
improve recovery of lignin particle
Page 91 and 92:
a reverse-phase column. Ether-linke
Page 93 and 94:
Figure 3: Relationship between 24hr
Page 95 and 96:
Figure 7: Relationship between 96hr
Page 97 and 98:
Ellis, W. C., M. Mahlooji and J.H.
Page 99 and 100:
EFFECT OF TYPE AND LENGTH OF DIETAR
Page 101 and 102:
intake data, the cattle fed the By-
Page 103 and 104:
cases of the diseases of interest:
Page 105 and 106:
for prediction of disease. The cate
Page 107 and 108:
Table 1. Receiver operator characte
Page 109 and 110:
INTEGRATING NUTRITIONAL AND GROUPIN
Page 111 and 112:
In a study conducted in a similar m
Page 113 and 114:
and 109°F (THI 94) during the stud
Page 115 and 116:
Gonzalez, M., A. K. Yabuta, and F.
Page 117 and 118:
In the past 20 years there has been
Page 119 and 120:
Dinosaur diets The plants eaten by
Page 121 and 122:
Figure 2 A,B,C,D: The relation betw
Page 123 and 124:
of fiber than ruminants while equid
Page 125 and 126:
supports the hypothesis that the fi
Page 127 and 128:
PHIDDLING WITH PHENYLALANINE: INFLU
Page 129 and 130:
competition of large neutral amino
Page 131 and 132:
A mixture of indispensable and semi
Page 133 and 134:
and in other experiments that are n
Page 135 and 136:
Table 4. Growth, feed intakes, PAH
Page 137 and 138:
Lu, J. and R.E. Austic. 2009. Pheny
Page 139 and 140:
During the late 1700s in Europe, th
Page 141 and 142:
of energy and protein nutrition bec
Page 143 and 144:
elated to the involvement of sodium
Page 145 and 146:
In practical nutrition, it is impor
Page 147 and 148:
Johnson, R. A. 1963. Habitat prefer
Page 149 and 150:
INTERPRETING AND IMPLEMENTING STARC
Page 151 and 152:
in starch content and corn silages,
Page 153 and 154:
INTERPRETING AND IMPLEMENTING STARC
Page 155 and 156:
All of the guidelines for starch di
Page 157 and 158:
Feedstuff N DM range IVSD 7 SD Corn
Page 159 and 160:
nonstructural carbohydrate / rumen
Page 161 and 162:
ANALYTICAL METHODS For good estimat
Page 163 and 164:
Larson, J., and P. C. Hoffman. 2008
Page 165 and 166:
Key Data In50 years, the world popu
Page 167 and 168:
With respect to increasing output,
Page 169 and 170:
THE CONSUMER PERSPECTIVE When it co
Page 171 and 172:
they want most in their food, consu
Page 173 and 174:
devastating in poor nations where e
Page 175 and 176:
additive for swine can reduce manur
Page 177 and 178:
DeCamp, S., Hankins, S., Carroll, A
Page 179 and 180:
DEMYSTIFYING THE ENVIRONMENTAL SUST
Page 181 and 182:
The „good old days‟ of dairy pr
Page 183 and 184:
„Grass-fed‟ beef production The
Page 185 and 186:
RECONCILING GLOBAL AND NATIONAL EMI
Page 187 and 188:
production, without negatively impa
Page 189 and 190:
assumed to be produced with similar
Page 191 and 192:
continent by the tractor trailer, a
Page 193 and 194:
REFERENCES Anon. 2006. Road to reco
Page 195 and 196:
http://faostat.fao.org/DesktopDefau
Page 197 and 198:
etail milk supply. The first repres
Page 199 and 200:
eliable recommendations about the h
Page 201 and 202:
nearly identical whereas MUFA was d
Page 203 and 204:
higher trans-11 18:1 and lower cont
Page 205 and 206:
diets varied on organic farms and s
Page 207 and 208:
Jensen, R. G. 1999. Fatty acid prof
Page 209 and 210:
the optimum standing NDF is 38% for
Page 211 and 212:
It is clear that fiber and lignin a
Page 213 and 214:
Figure 3. From: Progressive Dairyma
Page 215 and 216:
AMMONIA EMISSIONS FROM DAIRY BARNS:
Page 217 and 218:
lactating cow’s energy requiremen
Page 219 and 220:
exhaust duct per chamber. Stainless
Page 221 and 222:
(Harper et al., 2009) are significa
Page 223 and 224:
REFERENCES Aillery, M., N. Gollehon
Page 225 and 226:
FEEDING LOW CRUDE PROTEIN RATIONS T
Page 227 and 228:
- There was an increase in % milk t
Page 229 and 230:
formulating rations is a tool routi
Page 231 and 232:
REFERENCES .Higgs, R.J. 2009. Nitro
show all

2009 Proceedings of the Cornell Nutrition Conference For Feed ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?