Webinar O Nutricionista

Transcription

1 Webinar O Nutricionista

2 Webinar - O Nutricionista 9 de setembro 19:00 (segunda quarta feira do mês) Adam Lock PhD Universidade de Michigan Gordura para vacas de leite: qual o nível de precisão em fazendas comerciais. Foco na utilização de gordura e manutenção de vacas saudáveis.

3 Overview Lipid digestion & metabolism background Effect of FA chain length Effect of specific SFA Effect of degree of (un)saturation Interactions with other dietary components Effect of production level Meta-analysis

4 FATTY ACIDS IN DAIRY COW DIETS: ARE ALL FATTY ACIDS CREATED EQUAL? Adam L. Lock Associate Professor Department of Animal Science AMTS Webinar September 9, 2015

5 Overview Lipid digestion & metabolism background Effect of FA chain length Effect of specific SFA Effect of degree of (un)saturation Interactions with other dietary components Effect of production level Meta-analysis Studies with individual FA and also those using commercially available supplements

6 Fatty Acid Composition of Typical Feedstuffs Feedstuff (% FAME) 16:0 Palmitic 18:0 Stearic 18:1 Oleic 18:2 Linoleic 18:3 Linolenic Pasture (Grass) Grass Silage Alfalfa Hay Corn Silage Distiller s Grain Corn Oil Soybean Oil Calcium Salts PFAD Beef Tallow <1

7 Fats in plants are primarily unsaturated - Ruminant fats are saturated Unsaturated FA are Toxic to Rumen Bacteria Hydrolysis Biohydrogenation

8 Biohydrogenation Unsaturated FA Bacterial isomerases Trans intermediates H + + Bacterial hydrolyases Saturated FA

9 Unsaturated FA are Toxic to Rumen Bacteria Differential toxicity of PUFA to rumen bacteria, particularly those in the Butyrivibrio group Control (no added fatty acids) Linoleic acid added to cultures Main species that comprise rumen cellulolytic flora vulnerable to inhibition by PUFA Loss of Cell Integrity (cell death) Maia et al Antonie Van Leeuwenhoek. 91:

10 g/d Ruminal Bacteria Change Dietary Unsaturated FA Into Trans & Saturated FA :2 Intake 18:2 Duodenal Flow 18:0 Intake 18:0 Duodenal Flow < >400 < >400 Dietary Intake Range of 18:2 (g/d) Stearic acid (C18:0), under typical feeding situations, is the predominant FA available for absorption by the dairy cow Lock et al Proc. Cornell Nutr. Conf. pp

11 Biohydrogenation Direction is key Normal (good) Altered (bad) Linoleic Linoleic acid acid (cis-9, (cis-9, cis-12 cis-12 18:2) 18:2) Altered Fermentation Rumenic acid acid (cis-9, (cis-9, trans-11 CLA) CLA) trans-10, cis-12 cis-12 CLA CLA Vaccenic acid acid (trans-11 18:1) 18:1) trans-10 18:1 18:1 Stearic Stearic acid acid (18:0) (18:0) Stearic Stearic acid acid (18:0) (18:0)

12 Boerman et al J. Dairy Sci. (in press)

13 Trial Adjusted Total FA Duodenal Flow (g/d) Fatty Acid Flow Total FA Intake (g/d) Boerman et al J. Dairy Sci. (in press)

14 Trial Adjusted Total FA Digestibility (%) Trial Adjusted C18:0 Digestibility, % Fatty Acid Digestibility Total FA Duodenal Flow (g/d) Duodenal Flow of C18:0, g/d Boerman et al J. Dairy Sci. (in press)

15 Source of Milk Fatty Acids De novo synthesis C4 to C14 Part of C16 Acetate B-hydroxybutyrate Uptake of preformed fatty acids Part of C16 All long chain Absorbed from digestive tract Mobilized from body fat Fatty Acid % (weight basis) Common Name 4:0 4 Butyric 6:0 3 Caproic 8:0 2 Caprylic 10:0 3 Capric 12:0 4 Lauric 14:0 11 Myristic 16:0 29 Palmitic 16:1 2 Palmitoleic 18:0 12 Stearic 18:1 25 Oleic 18:2 2 Linoleic 18:3 1 Linolenic

16 Fatty Acid Composition of Typical Feedstuffs Feedstuff (% FAME) 16:0 Palmitic 18:0 Stearic 18:1 Oleic 18:2 Linoleic 18:3 Linolenic Pasture (Grass) Grass Silage Alfalfa Hay Corn Silage Distiller s Grain Corn Oil Soybean Oil Calcium Salts PFAD Beef Tallow <1

17 Percent of Samples Total Fatty Acids in Production TMR* (CVAS, ) 12% 10% N=5090 AVE. = 3.94 ST. DEV. = % 6% 4% 2% 0% Total Fatty Acids, % * NDF>=26% and NDF<=35%, CP>=14 and CP<=20

18 Percent of Samples Unsaturated Fatty Acids, Production TMR* (CVAS, ) 20% 18% 16% 14% 12% 10% 8% 6% 4% 2% 0% N=5090 AVE. = 2.66 ST. DEV. = 0.63 Unsaturated Fatty Acids, % * NDF>=26% and NDF<=35%, CP>=14 and CP<=20

19 Farm Predicted vs. Actual Dietary Fat Contents Wet Chem (% DM) Model (% DM) Actual Difference (% DM) % Difference % % % % % % %

20 Slide courtesy of Mike Jerred ADSA Midwest Section Dairy Meeting, March 2013 Factors affecting nutrient changes - Crop year and crop conditions - Processing changes and efficiency improvements FA Content of DDGS

21 Total Total FA FA Concentration (mg/g (% DM) DM) Feed Ingredient Variation Byproducts Canola 7.0 ± 5.8 % DM DG 12.2 ± 1.9 % DM Cottonseed 19.6 ± 2.1 % DM Klein et al J. Dairy Sci. 96 (Suppl. 1): 150.

22 Feed Ingredient Variation Forages FA, % DM Grass Silage Corn Silage Pasture Grazed Initial FA % DM Final FA % DM Mean Minimum Maximum Rye Annual Ryegrass Nov Mar Mar June Khan et al Anim Feed Sci Tech. 174: Freeman-Pounders et al Forage and Grazinglands fold variation

23 Total FA Concentration (% DM) Feed Ingredient Variation Corn Silage Mean 2.5 ± 0.3% DM Total FA ranged from 1.6 to 3.6% DM Variation in FA profile minimal compared with variation in total FA conc. Klein et al J. Dairy Sci. 96 (Suppl. 1): 150.

24 How/Why are People Feeding Fats? Commercially available fat supplements are included in dairy cow diets for a variety of reasons: - Increase caloric intake/energy density of ration - Maximize flexibility of ration formulation - Increase yield of milk and milk components - Combat heat stress - Improve reproductive efficiency - Improve BCS - Potential for the role of specific FA supplements

25 How/Why are People Feeding Fats? Response may depend on: - Form of fat/fa - FA profile (extent of unsaturation and/or carbon chain length) - Cow production level - Other dietary components Understanding the effects of different types of fat supplements on production parameters has direct impact on dairy industry recommendations

26 Potential Factors Contributing to the Successful Development of Fat Feeding for Dairy Cows Higher milk yield Increased use of high grain (corn) rations, leading to milk fat depression Maximizing high forage diets Increased availability of dry supplemental fats Recognition that specific FA may have beneficial effects

27 What Are the Negatives? Some FA may alter rumen BH Some FA may depress DMI Fats may depress rumen function, alter microbial population, and alter metabolism Individual FA can have vastly different effects Some fat supplements may be poorly digested The basal ration can influence the response Cost? Or more important: marginal return?

28 Fat Supplement FA Profiles Fatty Acid, g/100 g Tallow Ca-salt PFAD Mix Saturated free FA Supplements C16:0- enriched C14: C16: C18: C18:1 (n-9) C18:2 (n-6)

29 Figure 1 Supplementing fat in general conclusions: - Reduced DMI - Increased milk volume - Reduced milk fat protein and fat percentages - Increased milk fat yield and did not change milk protein yield - Therefore increased efficiency Rabiee et al J Dairy Sci. 95:

30 One problem Effects on production responses vary GREATLY even within fat supplement!!

31 Figure 1 n 15/15 27/23 29/21 4/4 10/10 89/77 Rabiee et al J Dairy Sci. 95:

32 Types of Fat Supplements Included PFAD calcium salts of palm fatty acid distillate - ~ 50% 16:0 - ~ 50% unsaturated 18-carbon FA PRILLS saturated fat prills - > 80% saturated FA (16:0 and/or 18:0) Tallow animal fat labeled as tallow - ~ 50% 16:0 and 18:0 - ~ 45% 18:1 Boerman et al J. Dairy Sci. 97 (E-Suppl. 1): 319

33 PFAD n = 56 PRILLS n = 30 Tallow n = 44 OVERALL n = 130 Study name Statistics for each study DMI, Difference Standard kg/d Lower Upper in means error Variance limit limit Z-Value p-value Andrew et al Andrew et al Beaulieu et al Beaulieu et al Beaulieu et al Beaulieu et al Canale et al Canale et al Cervantes et al Cervantes et al DeFrain et al DeFrain et al Erickson et al Erickson et al Garcia-Bojalil et al Garcia-Bojalil et al Garnsworthy et al Garnsworthy et al Garnsworthy et al Garnsworthy et al Harrison et al Harrison et al Harrison et al Harrison et al Harrison et al Harrison et al Harvatine et al Harvatine et al Holter et al Kent et al Moallem et al Moallem et al Moallem et al Moallem et al Moallem et al Rodriguez et al Rodriguez et al Rodriguez et al Rodriguez et al Salfer et al Salfer et al Schauff and Clark Schauff and Clark Schauff and Clark Schauff and Clark Schauff et al Schauff et al Schneider et al Simas et al Simas et al Sklan et al Umphrey Umphrey van Knegsel et al Weiss and Wyatt Wu et al Fat supplementation Fat supplementation reduced increased Estimate P-value < < Favours A Favours B Meta Analysis

34 Milk Yield, kg/d Estimate P-value PFAD n = < PRILLS n = < Tallow n = < OVERALL n = < Fat supplementation Fat supplementation reduced increased Boerman et al J. Dairy Sci. 97 (E-Suppl. 1): 319

35 PFAD n = 55 PRILLS n = 29 Tallow n = 37 OVERALL n = 121 Milk Fat Yield, kg/d Estimate P-value 0.05 < < < Fat supplementation Fat supplementation reduced increased

36 Milk Protein Yield, kg/d PFAD n = 52 PRILLS n = 29 Tallow n = 37 OVERALL n = 118 Estimate P-value < < Fat supplementation Fat supplementation reduced increased

37 Summary Overall fat supplementation increased yield of milk and milk components and reduced DMI However type of fat influenced response - PRILLS no reduction in DMI - Tallow no effect on milk fat yield - PFAD no effect on milk protein yield Study design only impacted milk fat yield when tallow was supplemented Level of fat inclusion and NDF of fat supplemented diets had little effect on production responses Boerman et al J. Dairy Sci. 97 (E-Suppl. 1): 319

38 Not All Fat Sources Are the Same! Carbon-chain length: - Short chain FA ( 6C), medium chain FA (8 to 14C), or long chain FA ( 16C) Saturation: - Saturated (e.g. C16:0, C18:0) or unsaturated (e.g. C18:1, C18:2, C18:3) Esterification: - Triglycerides or free FA Form: - Prilled, encapsulated, calcium salts

39 Milk Fat Yield (g/day) Milk Fat Concentration (%) Impact of Carbon Chain Length on Milk Fat 4,5 4,3 4,1 3,9 3,7 3,5 3,3 3,1 2,9 2,7 2,5 700 Control C14:0 C16:0 C18:0 C14:0 decreased the yields of milk and SNF, but increased the % of fat in the milk without altering fat yield. When C18:0 or C16:0 was included in the diet there was an increase in milk fat yield; C16:0 caused the greater increase. C12:0 did not appear to affect the yields of milk or SNF but it caused large reductions in % and yield of fat Control C14:0 C16:0 C18:0 Treatment Steele & Moore J Dairy Res. 35:

40 Impact of Carbon Chain Length on Milk Fat 18:0 14:0 12:0 P-value DMI, kg/d Milk yield, kg/d Milk Fat % Milk Fat Yield, kg/d t10 18:1, g/100 g cows in a 3x3 LS were infused once per d with 240 g per cow per d of respective FA treatment CNO 0 CNO 1.3 CNO 2.7 CNO 3.3 DMI, kg/d Milk yield, kg/d Milk Fat % Milk Fat Yield, kg/d trans 18:1, g/100 g cows an incomplete (one half) 4 4 Latin square conducted in 2 periods. Diets differed in conc. of coconut oil (CNO; ~75% medium chain FA): 0.0 (control) or 1.3, 2.7, or 3.3% CNO, DM basis. CNO: coconut oil contained ~ 41% 12:0, 20% 14:0, 10% 16:0, and 7% 18:1 Hollmann et al J Dairy Sci. 95:

41 Milk Production, kg/d Total FA, % Calculated Milk FA Yield (g/d) Abomasal Infusion of 16:0, 18:0, and 18:1 5,0 4,8 4,5 4,3 4,0 3,8 3,5 3,3 3, Total Milk Fatty Acids, % Control Palmitic Stearic Oleic Treatment Milk Production, kg/d Control Palmitic Stearic Oleic Treatment (500 g/d) Control Palmitic Stearic Oleic Treatment Mammary uptake and extraction efficiency higher for C16:0 compared with C18:0 Enjalbert et al J Nutr. 128: Enjalbert et al J Dairy Sci. 83:

42 Rela ve incorpora on of acetate into secreted fa y acids Mechanistic Support nmol fa y acid incorporated/2 h x 10 6 cells Effect of exogenous fatty acids on secretion of fatty acids synthesized de novo 250% 200% = C16:0 = C18:0 = C18:1 30 Incorporation of exogenous fatty acids into triacylglycerols C16:0 stimulated de novo synthesis and incorporation into TAG whereas other fatty acids were either neutral or inhibitory 150% 100% 50% Fa y acid concentra on (μm) Fa y acid concentra on (μm) Only minor differences in the esterification efficiency into TAG of various fatty acids, except for C16:0, which was a clearly better substrate than the other fatty acids tested Hansen & Knudsen J Dairy Sci. 70:1344

43 Responses to Supplemental C16:0 C16:0 supplementation (2% of diet DM): - Increased milk yield (1.1 kg/d) - Increased milk fat yield (80 g/d) - Increased 3.5% FCM (1.7 kg/d) - Increased feed efficiency (0.06 kg 3.5% FCM/kg DMI) - No effect on protein and lactose yields C16:0 Results were independent of level of milk production Piantoni et al J. Dairy Sci. 96:

44 Responses to Supplemental C18:0 C18:0 supplementation (2% of diet DM): - Increased DMI - Increased yields of milk and milk components Higher yielding cows responded more positively to C18:0 supplementation than lower yielding cows C18:0 Piantoni et al J. Dairy Sci. 98:

45 2% C16:0 vs. 2% C18:0 (99% C16:0 & C18:0) Milk Fat Yield (kg/d) Milk Fat Concentration (%) 3.8 C16:0 supplementation compared to C18:0 supplementation (2% of diet DM): - Increased milk fat yield (90 g/d) Increased 3.5% FCM (1.90 kg/d) - Increased feed efficiency (0.08 kg/kg) PA SA 1.65 Responses were independent of level of milk production PA 1.59 SA Rico et al J. Dairy Sci. 97:

46 Milk Fat Concentration (%) Responses to Supplemental C16:0 Milk Fat Yield (kg/d) Increased milk fat yield Increased 3.5% FCM Improved ECM/DMI Lock et al., 2013; Piantoni et al., 2013; Rico et al., 2014 Included at 2% of dietary DM (soyhulls or FA removed) Maximal yield of milk fat, FCM, and ECM when C16:0 was supplemented at 1.5% ration DM 4,05 4,00 3,95 3,90 3,85 3,80 3,75 0,00 0,75 1,50 2,25 C16:0 dose, % of ration DM 1,80 1,75 1,70 1,65 1,60 0,00 0,75 1,50 2,25 C16:0 dose, % of ration DM Rico et al J Dairy Sci. 96 (Suppl. 1): 659

47 Milk fat yield, kg/d C16:0 Dose x Basal Fat Interaction on Milk Fat Yield 1,90 1,85 1,80 1,75 1,70 1,65 1,60 LOW FAT HIGH FAT +170 g/d P = C +140 g/d P < 0.01 Q 1,55 1,50 0,00 0,75 1,50 2,25 C16:0 dose, % of ration DM SEM = 0.09 LOW FAT; 0.09 HIGH FAT Rico et al J Dairy Sci. 96 (Suppl. 1): 659

48 Total FA Digestibility, % Total FA Digestibility Low Fat High Fat 65 P value Dose = 0.01, Basal = 0.09 Basal x Dose = ,75 1,50 2,25 PA Dose, % of dietary DM Linear PA dose effect: P = 0.01 De Souza et al J. Dairy Sci. 98 (Suppl. 2): 867.

49 16-Carbon FA Digestibility, % 16-Carbon FA Digestibility P value Dose < 0.01, Basal = 0.01 Basal x Dose = Low Fat High Fat 0 0,75 1,50 2,25 PA Dose, % of dietary DM Quadratic PA dose effect: P= 0.01 De Souza et al J. Dairy Sci. 98 (Suppl. 2): 867.

50 18-Carbon FA Digestibility, % 18-Carbon FA Digestibility Low Fat High Fat 70 P value Dose = 0.05, Basal = 0.07 Basal x Dose = ,75 1,50 2,25 PA Dose, % of dietary DM Quadratic PA dose effect: P = 0.01 De Souza et al J. Dairy Sci. 98 (Suppl. 2): 867.

51 Total FA Digestibility (%) Responses to Supplemental C18:0 Supplemental Stearic Acid Variable 0.0% 0.8% 1.6% 2.4% SEM P - Value DMI, kg/d L = 0.02 Milk, kg/d NS Fat, kg/d NS Protein, kg/d NS ECM, kg/d NS C18:0 increased DMI, but had no effect on yields of milk or milk components Total FA Intake (g/d) Boerman et al J. Dairy Sci. 97 (E-Suppl. 1): 840

52 C18:0 Digestibility, % Total FA Digestibility (%) Total FA digestibility (%) FA Digestibility y = x R² = y = x R² = y = x R² = Duodenal Flow of C18:0, g/d Total FA Intake (g/d) Total FA intake (g/d) Boerman et al J. Dairy Sci. (in press) Boerman et al J. Dairy Sci. 97 (E-Suppl. 1): 840 De Souza et al J. Dairy Sci. 98 (Suppl. 2): 867.

53 Effect of FA Unsaturation of Supplemental Fats Diet Item Control SFA 1 MUFA 2 PUFA 3 SEM DMI, kg/d Milk Yield, kg/d Fat % Fat Yield, g/d 1,249 1,436 1, SFA = Saturated free fatty acid supplement 2 MUFA = Ca-salts of palm fatty acid distillate 3 PUFA = Ca-salts of soybean oil fatty acids Relling & Reynolds J Dairy Sci. 90:

54 Milk fat yield (kg/d) MUFA & PUFA Impact on Milk Fat Yield 1.2 NoFAT LOLL C18: MOLL C18:2 0.9 HOLL LOML MOML LOHL Dietary FA %DM P-values iso-fat C18:1 vs. C18:2 comparisons Oleic effect linear NoFAT vs. LOLL LOML vs. MOLL HOLL vs. LOHL Linoleic effect linear and quadratic 0.21 <.05 <.05 Slide courtesy of Lou Armentano He et al J Dairy Sci. 95:

55 kg/d Fat/Forage Interactions Diets supplemented with fat (mix of 16:0 + 18:0): - High-forage diets: increased energy intake was directed mostly to body reserves - Low-forage diets: increased energy intake was directed mostly to milk production DMI Milk - FAT + FAT - FAT + FAT 60:40 ratio 40:60 ratio Weiss & Pinos-Rodríguez J Dairy Sci. 92:

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57 Effect of Fat Source on Milk Fat & Energy Partitioning 8 Holstein cows in early lactation (77 DIM) Control diet (CON; 5.5% FA) 2.5% supplemental FA: Sat: Mix of 16:0 + 18:0 Uns: Ca-salt soy FA Con Sat Int Uns DMI, lb/d DE intake, Mcal/d Milk Yield, lb/d Milk Fat, lb/d BW gain, lb/d Harvatine & Allen J Dairy Sci. 89:

58 MFD = Repartitioning of Energy MFD MAMMARY Milk fat synthesis Signals regulating fat synthesis Energy ADIPOSE Enzymes that make fat Increase in signals that regulate fat synthesis Harvatine et al J. Nutr. 139: 849

59 Body Weight, kg Body Weight, kg Body Condition Score, pt Potential Effect of MFD on Energy Partitioning & Weight Gain % difference 0.4% difference 0.6% difference 730 3, , ,6 3, , ,3 3, , , , Days in 2,8 Milk Days in Milk Days in Milk

60 Boerman et al J. Dairy Sci. 98 (Available on-line)

61 Production Results Treatments P-value Variable HFF HS SEM TRT DMI, kg/d a Milk, kg/d ECM, kg/d % FCM, kg/d Fat, kg/d Fat, % < Protein, kg/d < Protein, % < ECM/DMI a a Significant pmilk treatment interaction Boerman et al J. Dairy Sci. 98 (Available on-line)

62 % of Energy Intake Energy Partitioning & Weight Gain 80 Milk Energy BW Gain ,03 72,8 10,1 67,9 Treatments P-value Variable HFF HS SEM TRT BW BCS < Change in BW, kg/d Change in BCS, pt/28 d Calculated energy values Apparent NE L intake, Mcal/d Milk, Mcal/d Body Tissue Gain, Mcal/d High Fiber/Fat High Starch Boerman et al J. Dairy Sci. 98 (Available on-line)

63 Implications Diets resulted in similar NE L intake but the high starch diet partitioned more energy toward BW gain, the high fiber and fat diet partitioned more energy toward milk High fiber and fat diets may diminish the incidence of over conditioning in mid and late lactation cows Boerman et al J. Dairy Sci. 98 (Available on-line)

64 Kg/d % FCM ECM LSLF LSHF HSLF HSHF LSLF LSHF HSLF HSHF HF increased FCM by 1.50 kg/d vs. LF P-Values Starch = 0.53, Fat < 0.01 Starch x Fat = 0.52 HF increased ECM by 1.15 kg/d vs. LF P-Values Starch = 0.85, Fat = 0.03 Starch x Fat = 0.51 Garver et al J. Dairy Sci. 98 (Suppl. 2): 552.

65 Body Weight Change kg/d 0,70 0,60 0,50 0,40 0,30 0,20 0,10 0,00 P-Values Starch = 0.03, Fat = 0.97 Starch x Fat = 0.40 LSLF LSHF HSLF HSHF Garver et al J. Dairy Sci. 98 (Suppl. 2): 552.

66 Fat + Protein yield, kg/d 3.5% FCM, kg/d BW change, kg/d Effect of fat supplements with different fatty acid profiles on milk fat and protein yield, 3.5% fat-corrected milk (FCM) yield, and body weight (BW) change 3,25 3,20 a a b b 1,20 1,10 a 3,15 b bc 47 c 1,00 b b 3,10 3,05 c 46 0,90 b 3, ,80 2, ,70 2,90 Control Bergafat Energy Megalac Control C16:0 C16:0 C16:0 Booster + + C18:0 C18:1 43 Control Bergafat Energy Megalac Control C16:0 C16:0 C16:0 Booster + + C18:0 C18:1 0,60 Control Bergafat Energy Megalac Control C16:0 C16:0 C16:0 Booster + + C18:0 C18:1 De Souza & Lock (Unpublished Results).

67 Energy supply is an important reason why we feed FA (fats) Cows producing 60kg milk/d 1.8 Mcal NE L /kg of dry matter (DM) Forages Concentrates Fats Cool season grass: 1.5 Mcal NE L /kg DM Corn grain: 2.0 Mcal NE L /kg DM Vegetable oil: 4.4 Mcal NE L /kg DM

68 Caloric vs. Non-Caloric Effects of Fatty Acids? Effect of specific fatty acids: - Yield of milk and milk components - Maintenance of body condition - Nutrient partitioning - Reproduction - Health FA profile of a fat supplement most likely the first factor in determining the response to it

69 Rumen 12:0; 14:0; 16:0; 18:0; 18:1; 18:2; 18:3; 20:5; 22:6 BH of UFA Shifts in BH pathways Effects on microbial populations Effects of NDF/Starch Small Intestine Effects on DMI Digestibility Mammary Gland Milk Fat Balance of 18-C + de novo FA Direct effect of specific FA? MFD Intermediates milk fat synthesis BW/BCS Adipose Tissue Use of FA for other purposes Glucose sparing? Delivery of N-3 + N-6 FA

70 Concluding Remarks Meta-analyses reveal overall benefits of fat supplementation on yield of milk and milk fat with a reduction in DMI, but Not all fat sources are the same! - Know what FA are in the supplement you are using: chain length and degree of un(saturation) key Important to consider possible effects of FA in the rumen (BH/MFD), in the small intestine (DMI/digestibility), and in the mammary gland (increased incorporation/substitution) More research is needed to clearly establish the effects of fat supplements at different stages of lactation and their interaction with different diets to make their use an informed decision Economics/marginal return should be continually evaluated/considered

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73 14 de outubro 19:00 (segunda quarta feira do mês) John Goeser PhD Rock River Laboratory O que o laboratório pode medir para ajudar o nutricionista a ter mais precisão na fazenda.

74 Sua empresa pode ser parceira no próximo Webinar. Ajude-nos a trazer aos nutricionistas Brasileiros o que existe de mais novo em nutrição de vacas leiteiras no mundo. Marianna.correa@terra.com.br

75 Cadastre-se nos nossos meios de comunicação para receber os slides em português e o Webinar gravado: Excelente material para treinamento de equipes/grupos de estudos

76 60 50 Dieta formulada para 5% de gordura Brasil EUA Argentina 0 Terá 5% de gordura na dieta Irá variar de 4% a 6% Irá variar de acordo com forragem Depende do manejo da fazenda Eu não sei

77 Eu recomendo adição de gordura na dieta Brasil EUA Argentina 10 0 Para aumentar leite Para aumentar sólidos Para melhorar eficiência Para melhorar ECC Eu não recomendo

78 60 Que tipo de gordura eu recomendo Brasil EUA Argentina 10 0 Mais barata Mais saturada Mais insaturada Depende da dieta Depende da marca, não sei o tipo

79 Eu não recomendo gordura para vacas 120 leiteiras Brasil EUA Argentina 20 0 É caro Não vejo resposta Diminui CMS Diminui gordura no leite Eu recomendo