FEEDING FOR MILK COMPOSITION - PowerPoint PPT Presentation

About This Presentation
Title:

FEEDING FOR MILK COMPOSITION

Description:

FEEDING FOR MILK COMPOSITION Jos Eduardo Portela Santos VMTRC UC Davis Milk Components Fat Content Fatty acid profile Crude protein Content True protein vs NPN ... – PowerPoint PPT presentation

Number of Views:111
Avg rating:3.0/5.0
Slides: 32
Provided by: Crist65
Category:

less

Transcript and Presenter's Notes

Title: FEEDING FOR MILK COMPOSITION


1
FEEDING FOR MILK COMPOSITION
  • José Eduardo Portela Santos
  • VMTRC UC Davis

2
Milk Components
  • Fat
  • Content
  • Fatty acid profile
  • Crude protein
  • Content
  • True protein vs NPN
  • Lactose
  • Minerals and vitamins

3
  • Several nutritional factors affect the
    composition of milk of dairy cows
  • Energy intake (Mcal of NEL)
  • Energy source
  • CHO
  • Lipids
  • Protein intake
  • Protein degradability and quality
  • Interactions between protein and energy
  • Amino acids
  • Minerals Na, K (DCAD)
  • Feed additives (Niacin, fibrolytic enzymes)

4
Milk Fat
  • ForageConcentrate ratio
  • CHO
  • NDF
  • Effective NDF
  • Physically effective NDF
  • Ruminal digestibility of NDF
  • NFC
  • Composition of the NFC sugars, starch and pectin
  • Ruminal degradability of starch

5
  • Ionophores
  • Fat supplementation
  • Lack of RDP (fiber digestibility and buffering
    effect)
  • Dietary buffers

6
Theories
  • Low fat diets
  • Acetate deficiency
  • B-OH-butyrate deficiency
  • High rumen molar concentration of propionate
    Insulin theory (glucogenic theory)
  • Vit. B12 deficiency
  • Trans fatty acids

7
(No Transcript)
8
(No Transcript)
9
(No Transcript)
10
(No Transcript)
11
Mechanism of Action of Trans FA
  • Milk fat suppression reduced SCFA (De Novo
    synthesis)
  • Trans fatty acids depress milk fat in 48 to 72 hs
  • Preliminary data from Maryland (Piperova et al.,
    1998)
  • Acetil CoA Carboxylase activity decreased (61)
  • Fatty acid synthase activity decreased (54)
  • Acetil CoA Carboxylase mRNA decreased (55)

12
Nutritional Causes of Milk Fat Suppression
  • Inadequate NDF
  • Inadequate physically effective NDF (particle
    size)
  • Poor NDF digestibility
  • Forage source buffering capacity
  • Excessive amounts of NFC
  • Excessive amounts of RDS
  • High fat diets

13
  • Fat sources with highly unsaturated FA profile
  • Yellow grease, oils
  • Interactions between fat source and forage source
    (binding sites)
  • Alfalfa hay vs corn silage
  • Protein supplements with high PUFA content
  • Fish meal, blends of marine by products
  • Lack of RDP (fiber digestibility buffer effect)
  • Lack of buffers

14
Milk Protein
  • NEL intake
  • ForageConcentrate ratio
  • Amount of fermentable CHO (RDS)
  • Dietary CP level
  • Amino acid profile of the protein flowing to the
    duodenum
  • Dietary fat

15
(No Transcript)
16
(No Transcript)
17
(No Transcript)
18
Effect of Grain Processing on Plasma Insulin
P lt 0.05
  • Data from 832 blood samples from 32 cows (Santos
    et al., 2000)

19
(No Transcript)
20
(No Transcript)
21
  • Diets with more fermentable energy increase milk
    protein
  • Increase flow of microbial protein
  • increase molar concentration of propionate in the
    rumen
  • increase blood insulin

22
Dietary Protein and Milk Protein
  • Low efficiency of N utilization for milk protein
    synthesis (lt 30)
  • Sp?rndly (1986) No relationship between dietary
    CP content and milk protein concentration
  • Emery (1978) correlation between dietary CP and
    milk protein content (r20.35)
  • The effect of higher CP diet is associated with
    greater DMI and total energy intake

23
(No Transcript)
24
(No Transcript)
25
(No Transcript)
26
Dietary Fat and Milk Protein
  • Negative relationship between dietary fat and
    milk protein concentration
  • Independent of fat source
  • Increased efficiency of amino acid extraction
  • Supplying more fermentable CHO or high quality
    RUP partially overcomes milk protein depression

27
(No Transcript)
28
(No Transcript)
29
(No Transcript)
30
Conclusions
31
(No Transcript)
Write a Comment
User Comments (0)
About PowerShow.com