Term
What is metabolizable protein? How is it defined? |
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Definition
Absorbable Protein
digestible microbial true protein (MTP) + digestible UIP |
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Term
How are metabolizable protein requirements predicted? |
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Definition
From net protein neids
-sum of tissue losses, gains, fecal/urinary losses, growth, fetal growth milk etc
-efficiency for use of gain is adjusted relative to physiological state & weight |
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Term
How are DIP and UIP requirements determined? |
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Definition
Based on MP requirements of animal |
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Term
What is the relationship between MP and UIP? |
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Definition
If MP req are high, UIP requirements also increase because MCP can't provide enough protein
MCP can provided most of the required MP if requirements are low |
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Term
How does diet type affect MP, DIP and UIP requirements? |
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Definition
If diet is high in fermentable energy/CHO -more DIP supplied -MCP production increases -UIP req may decrease
High energy diets provide lots of C skeletons to microbes to attach NH3 to, so can make more use of DIP |
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Term
Why is it important to meet the DIP requirement? |
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Definition
If DIP req not met:
-redued digestion of CHO (fiber) and starch bc not meeting needs of rumen microbes doing the work
-need to balance between available energy in the rumen and DIP (provide enough C skeletons for NH3 use) |
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Term
Why is it difficult to determine AA requirements in ruminants? |
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Definition
you can't predict what the microbes will do with the substrates they are provided in the diet |
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Term
What is the requirement for specific AA? |
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Definition
Variable depending on ani physiological state, what’s in diet, whats available to microbes and digesta processes of animal |
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Term
How can you compensate for deficient AA in diet? |
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Definition
can feed protected AA sources (met, lys, his etc) |
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Term
Why would you be able to feed a less protein-dense hay as animals grow? |
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Definition
as they get bigger they can consume more. also earlier on they are depositing a lot of muscle and bone, so have higher protein requirements. At the end they start to put on fat, less protein required |
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Term
How does lactation affect CP requirements? |
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Definition
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Term
When is the best time to improve body condition in a cow? |
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Definition
in her 2nd trimester, because calf will be weaned and she is not lactating |
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Term
Why would CP requirements of a breeding cow change so drastically throughout the year? |
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Definition
first two months post calving, high lactation = peak CP requirements
7 months post-calving calf is weaned, no more lactation
9-12 months increase again because cows re-bred, in last trimester, greatest nutrient demands for gestation |
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Term
Gestation period of a cow? |
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Definition
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