The Nutritionist 2019

Transcription

1 The Nutritionist 2019 Live and Recorded Ruminant Nutrition Webinars More Information at

2 14 February :00 am EST 5:00 pm EST Dr Rick Grant The Wm H Miner Institute Relationships between undigested and physically effective fiber in lactating dairy cows

3 Relationship between undigested and physically effective fiber in lactating dairy cows R. Grant 1, W. Smith 1, M. Miller 1, K. Ishida 2, and A. Obata 2 1 William H. Miner Agricultural Research Institute, Chazy, NY 2 Zennoh National Federation of Agricultural Cooperative Associations, Tokyo, Japan

4 Introduction Economic, environmental, and social considerations are encouraging use of higher fiber diets (Martin et al., 2017) Forage and non-forage NDF alone does not explain all observed variation in DMI and milk yield as dietary source and content vary Incorporate measures of digestibility and particle size

5 Current status: fiber digestion 3-pool model (Waldo et al., 1972; Mertens, 1977; Raffrenato et al., 2019) NDF Variable digestion pdndf Variable kd F-NDF S-NDF Variable k Fast Variable k Slow indf 2 Kd = 0 indf 3 Kd = 0 undf240 NDS Complete digestion NDS Complete digestion NDS Complete digestion

6 Use of undf240 as a benchmarking tool undf240 is sensitive to Genetics Maturity at harvest Growing environment Measurement of indf using undf240 provides dynamic estimate of Kd In the field, nutritionists have begun to use undf within herds along with NDF, NDFD, pendf (Nousiainen et al., 2003; 2004; Cotanch, 2015; Van Amburgh et al., 2015; Palmonari et al., 2015; 2016)

7 FCM/DMI (kg/kg) Physical effectiveness factor (pef) and pendf pef = physical effectiveness factor % of sample retained on 1.18-mm screen when dry sieved; 4.0-mm screen as fed pendf = physically effective NDF pendf = pef x NDF% Recommendation: 21-23% of DM (Mertens, 1997; Mertens, 2007) Function of CHO fermentability and feeding management (Zebeli papers) pendf1.18 (% of DM) 12 studies using vertical dry sieving and 1.18-mm sieve (Grant, 2008, unpublished)

8 Relationship between undf240 and pendf (Smith et al., 2018; ADSA abstracts) Practical feeding questions: What are separate and combined effects of pendf and undf240 in diets fed to lactating cows? Can we adjust for lack of pendf by adding more dietary undf240? If forage undf240 is higher than desired, can we partially compensate by chopping more finely? How important is particle size? Answer likely affected by source of fiber.

9 Miner Institute Study Objectives Evaluate the effect of feeding different dietary concentrations of undf240 and pendf on: 1) chewing behavior, 2) rumen dynamics, and 3) lactation performance of Holstein cows.

10 Dietary fiber and forage processing Two undf240 concentrations: Target: 8.5 vs 11.5% undf240 Adjusted forage% and NFFS Two pendf concentrations: Timothy hay Haybuster (hammer mill) High pef: 0.58 ± 0.04 Low pef: 0.24 ± 0.01

11 Screens used for chopping timothy hay Hammer mill 3 and 2 in 1/2 and 3/8 in 15.2 and 5.1 cm 1.3 and 0.95 cm

12 Timothy hay as fed

13 Dietary ingredient composition Low undf240 High undf240 Ingredient, % of DM Low pendf High pendf Low pendf High pendf Corn silage Straw, wheat Timothy hay short Timothy hay long Beet pulp, pelleted Grain mix

14 Dietary carbohydrate composition Low undf240 High undf240 Item, % of DM Low pendf High pendf Low pendf High pendf % Forage Starch Sugar andfom undf240om pendf

15 New concept: peundf240 Low undf240 High undf240 Item, % of DM Low pendf High pendf Low pendf High pendf undf240om pef 1.18-mm peundf peundf240 = pef x undf240om pef measured using Ro-Tap/1.18-mm screen or PSPS/4.0-mm sieve. undf240 uniformly distributed above and below 1.18-mm screen.

16 Treatment TMR

17 Dry matter and NDF intake Low undf240 High undf240 Item Low pendf High pendf Low pendf High pendf SE P-value DMI, kg/d 27.5 a 27.3 a 27.4 a 24.9 b 0.6 <0.01 DMI, % of BW 4.02 a 4.04 a 3.99 a 3.73 b NDF, kg/d 9.12 b 9.06 b 9.74 a 8.96 b NDF, % of BW 1.33 b 1.34 b 1.42 a 1.34 b abc Within a row different superscripts differ (P 0.05).

18 undf240 and pendf intake Low undf240 High undf240 Item Low pendf High pendf Low pendf High pendf SE P-value undf240, kg/d 2.41 c 2.43 c 3.11 a 2.87 b 0.05 <0.001 undf240, % of BW 0.35 c 0.36 c 0.45 a 0.43 b 0.01 <0.001 pendf 1.18, kg/d 5.56 b 5.94 a 5.07 c 5.44 b 0.11 <0.001 peundf240, kg/d 1.47 c 1.59 b 1.61 b 1.74 a 0.03 <0.001 abc Within a row different superscripts differ (P 0.05). Q: Does lactation performance track with peundf240 intake?

19 Milk yield and composition Low undf240 High undf240 Item Low pendf High pendf Low pendf High pendf SE P-value Milk, kg/d 46.1 a 44.9 ab 44.0 bc 42.6 c 0.9 <0.01 Fat, % 3.68 b 3.66 b 3.93 a 3.92 a Fat, kg/d True protein, % 2.93 a 2.88 ab 2.96 a 2.84 b True protein, kg/d 1.35 a 1.27 b 1.29 ab 1.19 c Urea nitrogen, mg/dl 8.5 c 9.4 bc 10.1 ab 11.0 a 0.6 <0.01 abc Within a row different superscripts differ (P 0.05).

20 ECM and efficiency Low undf240 High undf240 Item Low pendf High pendf Low pendf High pendf SE P-value ECM, kg/d 47.0 a 45.7 ab 46.4 ab 44.6 b ECM/DMI, kg/kg 1.71 ab 1.68 b 1.70 ab 1.79 a abc Within a row different superscripts differ (P 0.05). Milk and ECM track with peundf240 Milk fat % tracks with undf240 Interpret gross dairy efficiency carefully

21 Chewing responses Low undf240 High undf240 Item Low pendf High pendf Low pendf High pendf SE P-value Eating time, min/d 255 b 263 b 279 ab 300 a 12 <0.01 Eating time, min/kg DMI 9.09 c 9.62 bc b a 0.51 <0.01 Rumination time, min/d Rumination, min/kg DMI b b b a 0.80 <0.01 abc Within a row different superscripts differ (P 0.05).

22 Meal patterns Low undf240 High undf240 Item Low pendf High pendf Low pendf High pendf SE P-value DMI, kg/d Meal length, min 27.7 c 32.8 b 32.6 b 37.7 a 2.5 <0.001 Meal bouts, /d 11.3 a 10.5 ab 10.7 ab 10.0 b abc Within a row different superscripts differ (P 0.05). Greater intake and more meals with lower undf240 diets, and high undf240 diet chopped shorter.

23 Rumen Dive Something to chew on Emptied the rumen Fed each TMR Collected the swallowed bolus Assess particle size reduction due solely to chewing while eating

24 Particle size reduction during eating Diet Bolus Sieve size: 19 mm 13.2 mm 9.5 mm 6.7 mm 4.75 mm 3.35 mm Low/Low pendf, undf240 High/Low pendf, undf240 Low/High pendf, undf240 High/High pendf, undf240 Low/Low pendf, undf240 High/Low pendf, undf240 Low/High pendf, undf240 High/High pendf, undf240 Mean particle size (mm) 3 % 27 % 33 % 20 % 10 % 7 % % 27 % 29 % 16 % 9 % 6 % % 21 % 23 % 22 % 14 % 11 % % 13 % 17 % 20 % 11 % 7 % % 11 % 38 % 26 % 14 % 10 % % 11 % 22 % 29 % 20 % 16 % % 11 % 26 % 29 % 19 % 13 % % 12 % 19 % 28 % 21 % 14 % 7.78

25 Particle size of ingested feed (Schadt et al., 2011) Forage type NDF, % of DM Feed size, mm Bolus size, mm Chews /g NDF Long rye grass hay c mm rye hay a 9.9 c mm PSPS hay a 10.7 bc mm PSPS hay b 10.8 bc PSPS hay f 8.1 d 1.9 Grass silage c 11.6 ab 0.4 Corn silage e 11.2 bc 0.7 TMR d 12.5 a 0.6

26 Forage fiber and feeding behavior (Grant and Ferraretto, 2018) Greater eating time and possible lower DMI associated with: Higher forage content (Cotanch et al., 2012; Jiang et al., 2017) Corn silage and haycrop silage Lower NDF digestibility (Miron et al., 2007: Cotanch et al., 2012) Corn silage, sorghum silage Longer particle size (Fernandez et al., 2002; Kononoff and Heinrichs, 2003; Miller et al., 2017) Alfalfa silage, corn silage, wheat straw

27 Chewing meta-analysis (Krentz et al., 2018) n = 117 trials; 431 treatment means As eating time increases: Reduced milk protein, milk yield, and ECM yield As rumination time increases: Increased milk fat% and yield As total chewing time increases: Eating time between 3-5 h/d encourages natural feeding behavior Increased milk fat%, but decreased milk yield

28 Dietary forage (% of DM) and behavior responses (Jiang et al., 2017) Item 40% 50% 60% 70% Difference DMI, kg/d kg/d Eating, min/d min/d Rumination, min/d min/d Total chewing, min/d min/d Resting, min/d min/d Corn silage and alfalfa hay, primarily. Increased chewing time (mostly longer eating time) at expense of resting time.

29 Suggested PSPS targets: Miner Institute (2017) Sieve mm PSPS 2013 % Miner 2017 % Top <5 Mid >50 Mid Comments Sortable material, too long, increases time needed for eating; especially if >10% Still long and functional pef, more so than 4 mm material. Maximize amount on this sieve, 50-60% Functions as pef sieve, no recommendation for amount to retain here other than total on the top 3 sieves = pef Pan % grain diet results in at least 25-30% in the pan Keep feed in front of cow Comfortable stalls Part of a system

30 Ruminal fermentation Item Low undf240 Low pendf High pendf High undf240 Low pendf High pendf SE P-value Daily mean ph 6.11 b 6.17 ab 6.22 ab 6.24 a Total VFA, mm a ab ab b Acetate, % of total VFA Propionate, % of total VFA 22.7 a 22.5 a 21.5 b 21.6 b 0.83 <0.01 Acetate : propionate 2.83 c 2.89 bc 3.04 a 3.01 ab 0.15 <0.01 abc Within a row different superscripts differ (P 0.05).

31 Ruminal fiber dynamics Item Low undf240 Low pendf High pendf High undf240 Low pendf High pendf SE P-value Ruminal pool size, kg OM andfom undf240om 3.8 b 3.7 b 4.5 a 4.4 a 0.2 <0.01 Ruminal turnover rate, %/h OM andfom 4.4 x 4.4 x 4.2 xy 3.9 y undf240om abc Means within a row with unlike superscripts differ (P 0.05). xy Means within a row with unlike superscripts differ (P 0.10).

32 Perspectives to-date Book end diets resulted in expected responses in chewing, DMI, and ECM Low/high vs high/low undf240/pendf diets: Similar response in: DMI and ECM Rumen ph and VFA Fat %, mixed origin FA, and A:P ratio function of undf240

33 Perspectives to-date Reducing pendf with high undf240 diet: Lower eating time Shorter meal length, more bouts Greater DMI Faster rumen NDF turnover Don t forget that pendf is important for low undf240 diets. If future research confirms relationship between dietary undf240 and DMI, when forage fiber digestibility is less than desired, finer forage chop length may boost DMI and ECM.

34 Preliminary Synthesis: undf240 and peundf240 versus DMI, ECM, and Rumen ph (M. Miller, W. Smith, and R. Grant, 2019; unpublished)

35 Combined data from four studies Study 1: pendf and undf240 (Smith et al., 2018) Study 2: ~50 or 65% forage in ration DM (Cotanch et al., 2014) 13% haycrop silage (mixed mostly grass) 36 to 55% corn silage (bm3 or conventional) Study 3: ~42 to 60% corn silage (bm3 or conventional) and 2 to 7% fine vs coarse-chopped wheat straw (Miller et al., 2017) Study 4: ~55% conventional or bm3 corn silage, 2.3% chopped wheat straw (Miner Institute, unpublished, 2019)

36 Relationships 1 between Fiber and DMI/Meal Behavior (Miller, 2018) Fiber measure DMI, kg/d Meal duration, min Meal bouts, /d NDF, % of DM undf240, % of DM pdndf, % of DM Pearson correlations. undf240 related to DMI ballast Potentially digestible NDF related to number of meals (fast pool of NDF)

37 undf240 and DM Intake

38 peundf240 and DM Intake

39 undf240 and ECM Yield

40 peundf240 and ECM Yield

41 undf240 and Mean Rumen ph

42 peundf240 and Mean Rumen ph

43 peundf240 and DM Intake Future: adjust chop length based on undf240, digestion characteristics?

44 A Tale of Two Fibers Research needed to test relationship with: Alfalfa-based diets Potential differences between grasses and legumes Pasture systems Forage vs non-forage fiber sources Feeding scenarios markedly different than high corn silage/haycrop diets There appears to be value in integrating two measures of fiber - undf240 and pendf - when formulating rations.

45 Thank you

46 14 March :00 am EDT 6:00 pm EDT Dr Mike Van Amburgh Cornell University Feeding Calves

47 Webinar Co-Hosts

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