Forage & Feed Analyses

Question 1

Describe quality analysis.

Answer 1

-determines nutrient levels in feedstuffs
-most effective feedstuff management tool
>elim guess based on visual appraisal

Question 2

Describe the components.

Answer 2

• Moisture
• Dry Matter
• Crude Protein
• Neutral Detergent Fiber
• Acid Detergent Fiber
• Total Digestible Nutrients
• Net Energy
• Minerals

Question 3

Describe ration calculations.

Answer 3

-forage & feed nutrient comp eval on DM or as fed basis
-as fed basis incl moisture content in each nutrient listing
>as fed nutrient values less than DM nutrient values

Question 4

Describe moisture.

Answer 4

-imp in stored forage samples
-excessive moisture in hay = quality loss, over heating, fires
>moisture above 18% in round bale form or 20% in small squares = risk of fire
-quality silage or baleage need recommended range for moisture content at harvest to ensure proper ensiling
-low moisture = overheating, lower feeding value, inc DM loss
-excessive moisture = seepage, nutrient loss, unpalatability
-high moisture feed = shorter storage live or require controlled storage conditions to min spoilage & mold
-determines true value of feed
>feed at 70% moisture = 600lbs true feed

Question 5

Describe dry matter.

Answer 5

-DM = subtract moisture content from 100
>ration building easier bc feeds compared on same basis
>use nutrients on DM basis
-grain & hay = DM 85%
-silage & wet distiller grain = DM 25-35%
-baleage = DM 50-70%
core sampling

Question 6

Describe dry matter intake (DMI).

Answer 6

-% of NDF in forage inc = animals consume less
-DMI est by: (120)/(%NDF)
EX: NDF value of forage is 40% -> DMI is 120/40 = 3% BW

Question 7

Describe crude protein (CP).

Answer 7

-based on nitrogen content of feed
-est 6.25 x nitrogen content
>incl non protein sources (ex. Urea)
-grains = CP 8-14%
-corn = CP 7-9%
-wheat & oats = CP 12-14%
-cottonseed & soybean meal = CP 40-50%
-dried distiller grain = CP 23-29%
-hay = CP 4-20%

Question 8

Describe neutral detergent fiber. (NDF)

Answer 8

-value ID all cell wall content + acid detergent fiber content
-cellulose, hemicellulose, lignin
-represents total fiber component of feedstuff
-predict intake by animals consuming feedstuff
>NDF inc = intake decrease
>no bearing on quality & digestibility

Question 9

Describe plant carbohydrates.

Answer 9

Question 10

Describe acid detergent fiber. (ADF)

Answer 10

-value = level of cellulose & lignin in plant
>imp bc lignin is indigestible
>grains & mixed rations = lower ADF
>forages have higher ADF (40%)

Question 11

Describe physically effective fiber. (Pe)

Answer 11

-measure fraction of fiber that stim chewing
>contribute to rumen floating mat of lg particles
-peNDF in TMR (total mixed ration) = directly correlated to milk fat conc
-diet high in peNDF promote rumination & saliva
>high rumen pH inc production of VFA (esp acetate & butyrate)

Question 12

Describe particle separator.

Answer 12

-on farm assessment tool to eval physically effective fiber content
-8-10% ration in top box

Question 13

Describe total digestible nutrients. (TDN)

Answer 13

-est of energy content of roughage/feed
-calc by formula that uses ADF, NDF, CP, & ash
>low quality hay = 40-50% TDN
>high quality = 50-60% TDN
>grains = 70-80% TDN

Question 14

Describe net energy for maintenance, gain, & lactation.

Answer 14

1. Maintenance = needed for maintain bod temp, physical activity, heartbeat, breathing
2. Gain = productive purpose like deposition of protein & fat
3. Lactation = for milk prod

Question 15

Describe relative feed value. (RFV)

Answer 15

-RFV & relative forage quality (RFQ)
>account for animal resp to forage qual
-incl digestible dry mater (DDM) & DMI in calc
-DDM is % of forage sample that’s digestible

Question 16

Describe forage quality.

Answer 16

-leafiness, stem thickness, color, smell, content of protein, fiber, lignin
-improve w higher CP & DDM
-qual decrease w higher fiber
-higher DMI expected on higher qual forage

Question 17

Describe feed quality.

Answer 17

-color, odor, texture, presence/absence of mold