Canola meal, corn dried distiller’s grains and recent developments in amino acid nutrition of dairy cows

Get Complete Project Material File(s) Now! »

Chapter 4. Experiment 1: Determining the optimal ratio of canola meal and high protein dried distiller’s grain in rations of high producing Holstein dairy cows

Abstract

Use of canola meal (CM) and dried corn distillers grains with solubles (DDGS) as major supplemental protein sources are common practice in North American dairy rations and usage of both is projected to increase in the future. Since limited data is available on performance of cows fed rations with different ratios of CM and DDGS, our objective was to determine the optimal ratio of CM to DDGS protein in a contemporary lactation dairy ration by feeding combinations of CM and high protein DDG (HPDDG) to early lactation multiparity dairy cows. The experiment was a 4 x 4 Latin square with 28 d periods using four pens of ~320 high producing cows/pen. Treatments were created by varying the amounts of CM and HPDDG added on a DM basis to be: (1) 0 g CM/kg and 200 g/kg HPDDG, (2) 65 g CM/kg and 135 g/kg HPDDG, (3) 135 g CM/kg and 65 g/kg HPDDG, (4) 200 g CM/kg and 0 g/kg HPDDG. Dry matter intake was not affected by the CM/HPDDG ratio in the ration. Milk and lactose yield, true protein (TP) concentration and yield, milk fat yield as well as milk energy output increased at a decreasing rate with a higher CM/HPDDG ratio. Maximum values for milk and TP yield were at ~135 g CM/kg, while lactose, TP concentration and milk energy were maximized at ~120 g CM/kg inclusion. Milk fat concentration and milk energy density decreased linearly with higher CM inclusion. Body condition score change responded quadratically with the highest gain at ~120 g CM/kg inclusion. The purine derivative to creatinine index increased linearly with higher CM inclusion levels, suggesting that microbial protein production (MCP) was limited in the 0 g CM/kg ration and was progressively stimulated by higher feeding levels of CM. Plasma AA concentrations suggest that the reduction in lysine in dietary protein, together with the decrease in MCP synthesis, resulted  in  a  substantial  reduction  in  lysine  available  for  milk  production,  thereby  limiting performance in the higher HPDDG ration. The only AA which decreased in plasma with higher CM feeding levels were phenylalanine, leucine and methionine. That the concentration of leucine in the plasma was still decreasing linearly, while methionine and phenylalanine responded quadratically at the 200 g CM/kg treatment, was interpreted to suggest that the leucine supply remained higher than its requirement at the highest CM inclusion level, but that phenylalanine and/or methionine was limiting production in the highest CM ration. Overall, results suggest that the optimum ratio of CM to HPDDG in these rations was with 120 to 135 g/kg of ration DM from CM. Keywords: Milk production; Spot urine purine; Plasma amino acids.
Abbreviations: AA, amino acid; ADF, acid detergent fiber; ADICP, AD insoluble CP; AL, allantoin; aNDF, amylase-treated NDF; aNDFom, aNDF free of residual ash; AP, absorbable protein; BCS, body condition score; BUN, blood urea N; BW, body weight; CM, canola meal; CP, crude protein; CR, creatinine; DC305, DairyComp 305 management system; DDGS, dried distillers grains with solubles; DHIA, Dairy Herd Improvement Association; DIM, days in milk; DM, dry matter; EAA, essential AA; HPDDG, high protein DDG; MCP, microbial CP; NDF, neutral detergent fiber; NEL, net energy for lactation; OM, organic matter; PD, purine derivatives; PDC index, PD to creatinine index; RDP, rumen degradable CP; RUP, rumen undegradable CP; SCC, somatic cell counts; TMR, total mixed ration; TP, true protein.

Introduction

Protein nutrition is critical for high production efficiency of lactating dairy cows because it impacts their performance and the environment. Sufficient dietary protein is required to optimize production while an excess has negative effects on the environment, primarily when excreted as urea in urine. The major protein sources used in western areas of North America include high quality alfalfa hay, whole cottonseed or cottonseed meal (CSM), dried distillers grains with solubles (DDGS) and canola meal (CM). Due to the variable quality and high price of alfalfa hay, and the presence of secondary compounds (i.e., tannins and gossypol) in cottonseed, their inclusion levels in dairy rations are limited. Therefore, use of CM and DDGS as major supplemental protein sources is currently very high in many US dairy rations.
The Canola Council of Canada developed an initiative (Growing Great 2015) which aims to double 2011 production of CM by 2015 through increased crushing capacity in Canada (Canola Council of Canada Annual Reports, 2010; 2011). The USA is the main market for CM exports from Canada, receiving over 50% of their total CM exports with over 90% of this imported CM being utilized by the California dairy industry (USDA, 2011; Nernberg, 2012). Due to steadily increasing crude oil prices, the corn ethanol production industry in the Midwestern USA has been expanding rapidly since 2000, and increased production of corn distiller’s grains, the major by-product of the corn-starch ethanol industry, is projected to continue in coming years, at least as long as government subsidies persist (Wisner, 2010). As supplies of CM and DDGS increase, so will pressure to use these products as major protein supplements in dairy cattle rations. However, with as much as 400 g/kg of the crude protein (CP) in contemporary California total mixed ration (TMR) already coming from corn products, which is known to be limiting for milk protein synthesis in some amino acids (AA), particularly lysine, inclusion of even more corn DDGS protein could have a detrimental effect on production due to AA imbalances at the intestinal absorptive site, as well as by adding excess corn oil to already corn oil rich diets.
Studies comparing CM to DDGS have reported that higher proportions of CM, included at up to 66 and 104 g/kg DM respectively, tended to have higher absolute values for milk and protein yields (Mulrooney et al., 2009). However, negative effects of high levels of unsaturated fatty acids in corn oil on milk production, often reducing milk fat concentration and yield (Hollmann et al. 2011; Liu and  Rosentrater,  2011), necessitates use  of a low oil alternative  to conventional DDGS when experimentally comparing dietary protein sources involving corn based DDGS. High protein DDG products (HPDDG) provide the opportunity to do this as they have a very similar proximate nutrient profile to CM (Table 4.1).
Christen et al (2010) suggested that HPDDG outperformed CM at 120 g/kg ration DM, and there were indications that cows fed the HPDDG ration had an improved plasma AA balance versus CM, with a more desirable AA profile for milk protein production. However, adding HPDDG to diets which are already high in corn proteins may lead to lysine becoming limiting to milk production. Also, CM and HPDDG have very different CP degradability profiles with CM being primarily a rumen degradable CP (RDP) source while HPDDG is a high rumen undegradable CP (RUP) source (data summarized by Mulrooney et al., 2009). This means that a higher inclusion level of either could lead to an imbalance in the dietary RDP:RUP ratio, thereby negatively affecting rumen function, and/or creating an imbalance in AA available to support milk production. Few studies have been completed  comparing  dairy  cattle  performance  between  CM  and  HPDDG  directly,  and  little information is available on inclusion levels higher than 120 g/kg for either protein source.
The  objective  was  to  determine  the  optimal  ratio  of  CM  to  DDGS  protein  as  the  sole supplementary dietary protein source in rations which are relatively high in corn proteins, provided as corn grain and corn silage, by feeding combinations of CM and HPDDG to high producing dairy cows, thereby comparing the two protein sources without negative confounding effects from corn oil in conventional DDGS.

Materials and methods

The experiment was a 4 x 4 Latin square with 28 d experimental periods, and it took place from October 2011 to February 2012. The William’s experimental design (Williams, 1949) was used to generate a uniform design balanced for potential carry-over effects between treatments, as every treatment was fed in every period and to each pen, but never in the same sequence among pens.
All cows were cared for relative to applicable laws of the state of California and the USA, consistent with requirements for “The care and use of animals for scientific purposes”, as per the South African National Standard (SANS 10386-2008).

Farm and management

The commercial dairy farm selected for this study is located near Hanford (CA, USA) and milks ~5000 Holstein cows three times a day starting at 04:00, 12:00 and 20:00 h. Cows were housed in free stall barns, bedded with dried manure solids, with access to an outside dry lot and had fresh water available ad libitum. As per normal farm practices, cows were randomly allocated once a week from a single fresh pen at ~20 days in milk (DIM) to one of four early lactation pens. Each of the four pens housed ~320 multiparity early lactation cows (i.e., those cows which had cleared the fresh pen but were not yet confirmed pregnant) with similar lactation characteristics. Once confirmed pregnant, cows are moved from these pens to mid lactation pens. Normal cow movement in and out of the lactation pens was minimally restricted by the study. Treatments were randomly allocated to one of the four early lactation pens at the start of the 1st  period and rotated after each 28 d experimental period as described above for a William’s design.

Diets

The four rations were formulated by the farm nutritionist to be iso-nutritious for CP and fat, thus allowing comparison of CM and HPDDG as protein sources without confounding treatment effects with other ration nutrient changes, especially dietary fat levels. Treatments were created by varying the ratio of CM and HPDDG added to the ration at 200 g/kg TMR dry matter (DM), while the other 800 g/kg remained the same among treatments. On a DM basis, treatments were designed to be: (1) 0 g CM/kg and 200 g HPDDG/kg, (2) 65 g CM/kg and 135 g HPDDG/kg, (3) 135 g CM/kg and 65 g HPDDG/kg, (4) 200 g CM/kg and 0 g HPDDG/kg TMR DM.
Cows were fed a TMR which was prepared immediately before each feeding by mixing the individual ingredients (i.e., alfalfa hay, wheat and corn silages, CM, HPDDG) and a premix containing the dry ingredients (i.e., almond hulls, oat hay, steam flaked corn grain, cracked pima cottonseed, liquid molasses, mineral premix) in a conventional 2 screw vertical mixer. Cows were fed each morning between 04:30 and 07:30 h, while the cows were at morning milking, and again between 11:00 and 12:30 h for ad libitum intake. Each pen received a total of ~15,500 kg of as mixed TMR/d, split into 2 loads (i.e., one full 8,500 kg load of TMR at 1st feeding with a second ~7,000 kg load of TMR at 2nd feeding with the exact amount determined by the feeder). Each 1st feeding of TMR was fed to a clean bunk as bunks were cleared of all residual feed, which was weighed daily by pen, immediately prior to the 1st feeding. Weights for each load of TMR fed were recorded on record sheets at the time of feeding and used together with daily refusals to calculate DM intake per cow/pen. The “TMR tracker” system (Digi-Star LLC, Fort Atkinson, WI, USA) kept a record of the actual ingredient profiles of each batch of TMR mixed.

Declaration
Acknowledgements
Summary
List of Abbreviations
List of Tables
List of Figures
Preface
Chapter 1: General Introduction
Chapter 2: Literature Review: Canola meal, corn dried distiller’s grains and recent developments in amino acid nutrition of dairy cows
2.1. What is Canola meal?
2.2. What is corn dried distiller’s grain?
2.3. Comparing protein sources
2.3.1. Animal performance
2.3.1.1. Corn dried distiller’s grains
2.3.1.2. Canola meal
2.3.1.3. Comparing CM and DDGS.
2.3.2. Possible nutritional limitations of canola meal and high protein corn dried distiller’s grains
2.3.2.1. Protein degradability
2.3.2.2. Amino acid profile
2.4. Protein and amino acid nutrition of dairy cows
2.4.1. Microbial protein production and estimation
2.4.2. Predicting amino acid limitations…
2.4.2.1. Uptake to output ratios
2.4.2.2. Amino acid transfer efficiency
2.4.2.3. Amino acid extraction efficiency
2.4.3. Amino acid supplementation
2.4.3.1. Lactational responses to supplementation of other amino acids
2.4.3.1.1. Histidine
2.4.3.1.2. Branched-chain amino acids (BCAA)
2.4.3.1.3. Phenylalanine and Tyrosine
Chapter 3: Project Objectives
Chapter 4. Experiment 1: Determining the optimal ratio of canola meal and high protein dried distiller’s grain in rations of high producing Holstein dairy cows
4.1. Introduction
4.2. Materials and methods
4.3. Results.
4.4. Discussion.
4.5. Conclusions
Chapter 5. Experiment 2: Effects of ruminally protected methionine and/or phenylalanine on performance of high producing Holstein cows fed rations with very high levels of canola meal.
5.1. Introduction
5.2. Materials and methods
5.3. Results
5.4. Discussion.
5.5. Conclusions
Chapter 6. Experiment 3: Rumen microbial protein flow, and plasma amino acid concentration, spectrum in early lactation multiparity Holstein cows fed commercial rations.
6.1. Introduction.
6.2. Materials and methods
6.3. Results
6.4. Discussion
6.5. Conclusions
Chapter 7. Experiment 4: Impacts of increased levels of ruminally protected phenylalanine, supplemented to rations containing high levels of canola meal, on performance of high producing Holstein cows
7.1. Introduction
7.2. Materials and methods
7.3. Results
7.4. Discussion
7.5. Conclusions
Chapter 8: General Discussion
8.1. Conclusions and implications
8.2. Future research and critical evaluation
References
GET THE COMPLETE PROJECT