7/26/2019 Lecture 4--Acidosis--Final.pdf

1/8

Ruminal AcidosisSource articles:

Ruminal Acidosisunderstandings,

prevention and treatment

Rumen Acidosis With Special Emphasison Diagnostic Aspects of Subclinical

Rumen Acidosis: A Review

7/26/2019 Lecture 4--Acidosis--Final.pdf

2/8

Rumen pH pH of 6-7-- ideal for microbial growth and activities to

break-down roughage.

Concentrate diets -- rumen pH below 6 ---in general anegative effect (lower butterfat percentage-- lowbutterfat-syndrome, depressed appetite, metabolicdisorders, and possibly death).

At pH below 4, -- acidosis---lead to laminitis (hoofproblems) and ketosis (fat cow syndrome).

?

At pH level below 3, --- shock and die of toxaemia.

A higher pH (>7) -- caused by urea toxicity (alkalosis) --possibly death.

Note: monogastrics have a stomach pH 2.

7/26/2019 Lecture 4--Acidosis--Final.pdf

3/8

mechanisms could lower ruminal

pH (Lean et al. 2000)Access to preformed acids in feeds, such as

some silages;

A failure to produce buffering with ndogenously

derived buffers such as salivary bicarbonate;

Production of lactic acid in the rumen

Production of large amounts of weak volatile fatty

acids, acetic acid, butyric acid and propionic acid.

7/26/2019 Lecture 4--Acidosis--Final.pdf

4/8

Overview

7/26/2019 Lecture 4--Acidosis--Final.pdf

5/8

7/26/2019 Lecture 4--Acidosis--Final.pdf

6/8

AcidosisSchematic View (Feed)

7/26/2019 Lecture 4--Acidosis--Final.pdf

7/8

AcidosisSchematic View (Microbe)

7/26/2019 Lecture 4--Acidosis--Final.pdf

8/8

Mechanistic Modeling