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Flashcards in Non protein nitrogen Deck (18):
1

Nonprotein nitrogen (NPN) source

- Urea in improper doses
- ammonium salts/ ammoniated feed products

2

properties of NPN

- liberate ammonia
- rumen microflora change urea to ammonia and CO2
- aminates ketoacids to amino acids

3

NPN toxicosis

- amino acids form bacterial protein
- converted then to animal protein
- alkaline pH enhances hydrolysis

4

Factors affects NPN toxicity

- species (ruminants and horses most susceptible)
- compound (urea is most toxic)
- animals less than a year old
- fasted animals
- dehydrated animals

5

Usual ration of urea in grain ration vs. total ration

3% in grain
1% in total

6

Toxic dose in cattle that have not been previously exposed to NPN

0.45 g/ kg

7

Age range that is tolerant of NPN

3-6 weeks

8

Feed that is rich in urease

- soybean
- increases toxicity
- high fiber diets as well

9

NPN ionization

- ammonia produced in the rumen at normal pH is non ionized
- ammonia produced in an alkaline rumen is non ionized

10

Processing of non ionized ammonia

- can cross cell membranes, BBB and placenta
- absorbed by liver
- converted to urea
- excreted in the urine

11

Too much ammonia =

hyperammonemia

12

MOA of NPN

- Ammonia inhibits the citric acid cycle
- no energy, decreased cellular respiration, tissue damage

13

Death from NPN can be

cardiac or respiratory

14

Clinical signs of NPN

- rapid onset (30 min to 3 hours)
- restlessness, aggression, tremors, teeth grinding
- Bloat, rumen stasis, colic
- sternal recumbency while standing on hind legs
- death in 1-2 hours

15

Lesions form NPN

- no particular ones
- mainly due to vascular damage
- ammonia odor
- very bloated dead animals

16

Lab diagnostics

- inspect feed
- whole blood, rumen fluid and eye fluid for ammonia
- elevated rumen pH
- freeze specimen

17

Differentials

- Colic causing agents
- lead, chlorine or hydro carbon pesticides
- organophosphates

18

Treatment of NPN

- relieve bloat first
- Acetic acid/ vinegar to acidify the stomach
- normal saline for dehydration
- sodium bicarb for acidosis
- rumenotomy