Final Exam Flashcards
What are the phases of production?
1) cow/calf
2) Stocker/backgrounding
3) Feedlot
Describe the cow/calf phase
Breeding, calving, suckling calf to 6-10 months (500lbs)
Location: Dry lots and pasture
Primary Feedstuffs: preserved forages, pasture
Describe the stocker and backgrounding phase.
Growing for 2-6 months (500 to 1000 lbs)
Location: Pasture
Primary Feedstuffs: Pasture
Describe the Feedlot phase
Finishing for 4-5 months
Location: Dry lots
Primary Feedstuffs: preserved forages + grains
What are the impacts on cow/calf nutrient requirements?
1) intake
2) nutrient digestibility and composition (GE to NE)
3) maintenance
4) production
What are the variables of maintenance
-mature body weight
-physical activity
-temperature regulation
-body condition score
What are the variables for production
-Growth (heifer vs. mature)
-Gestation (open vs. gestating)
-Lactation (dry vs. lactating)
What are the 4 sub stages of cow calf nutrition
1) calving to breeding
2) breeding to weaning
3) mid gestation
4) pre-calving
Describe the calving to breeding sub stages
-highest nutrient requirement
-90 days
-NE(m) + high NE(L)
Describe the sub stage breeding to weaning
-150 days
-NE(m) + decrease NE(L) + increase NE(g)
Describe the sub stage mid-gestation
90 days
NE(m) + 2x increase NE(g)
Describe the sub stage pre-calving
90 days
NE(m) + 3x increase NE(g)
Effects of poor nutrition on cows and calf
Cow: dystocia, delayed return to estrus, and poor subsequent conception
Calf: poor survival rate, low milk available/WW, and muscle/fat deposition
What are the roles of the stocker/backgrounding phase
-intermediary between cow/calf, feedlot
-“straighten out”
-Add value (maximizing ADG to increase wt. in backgrounding, and use low cost forage to max. Margin over feed costs in stocker)
Describe “straightening out”
-group into market groups of age and type
-manage stress to stabilize health (milk to solid feedstuffs, co-mingling, transport, processing and vaccination)
Describe stocker vs. backgrounding
Stocker: transition weaned calves to thin stocker calves to improve the value of lower quality feedstuffs/forages
Backgrounding: Transition weaned calves to fattened feeder calves ready for high-energy diets
What is limit feeding
Involves replacement of a lower energy diet fed free choice with a higher energy diet fed in smaller amounts.
Requires close control of the amount of feed delivered to bunk daily.
Why choose limit feeding over ad-lib feeding?
Can substantially improve conversion efficiency relative to ad lib feeding.
Effects of poor nutrition on stocker/background cattle
Reduced cattle margin
Lower rate of gain
Lower value of added grain
Purchasing/marketing issues
What’s is different in feedlot nutrition
Maximize ADG shifts to IM far deposition
How can you transition feedlot cattle from high roughage to high concentrate diets
-initially restrict intake of high concentrate, high energy diet and gradually increase amounts fed until desired diet composition achieved (not ideal method)
-gradually replace high roughage diet with diet of progressively greater grain content until desirable diet composition achieved (preferred method)
What diet types does feed intake regulation depend on?
High forage: rumen capacity (DMI)
High grain: chemostatic mechanism (energy level)
What is the limit feeding approach
Intake of a single high concentrate diet is gradually increased over a period of 2-3 weeks
What is the step up approach
Concentrates incrementally replace roughage over a period of 3 weeks using 4-5 different diets
What is the two-ration approach
Uses 2 diets
Required multiple feedings each day
Feedlot regimen for 3 daily feedings
-starter diet fed meals 1 2 and 3, repeat x7 days
-starter fed meals 1 and 2, finisher fed meal 3, repeat x 7 days
-starter fed mea 1, finisher fed meal 2and3, repeat x7 days
-finisher fed meals 1 2 3 starting day 22. Cont. until slaughter
Effectively creates “steps”
-60, 71, 82, and 93% concentrate
Feedlot nutrient requirements
Water
Energy intake
Protein
Minerals and vitamins
Why is energy intake important
Dictates rate of growth and efficiency
Why is protein important
Deficiency of ruminant available proteins limits carbohydrate fermentation
-microbial protein is primary protein source for the animal
-dietary protein is supplied via byproducts or ruminally degrading nitrogen sources like soy meal and urea
What mineral and vitamins are needed
Always added: Ca, Na, vitamin A, Co, Cu, I, Mn, Se, Zn
Usually added: K, S, Vitamin E
Rarely/never added: P, Vitamin D (unless indoors)
Disease caused by poor nutrition
-Acidosis
-bloat
-founder
-liver abscesses
-polioencephalomalacia
-urinary calculi
Significant changes in dairy industry in 50 years
-cows now maintained in confinement
-herds are larger and more efficient
-grain makes up 50% of lactation diet
-milk production per cow is 2-4x more than prior to 1960
What is major difference between dairy cow diets?
Dry = 90% and 10%
Transition = 70% and 30%
Lactation = 50% forage 50% grain (1:1)
When is the “dry cow” diet given
Fed 20-40 days immediately prior to the transition diet
What are the goals during the dry cow diet
To maintain moderate body condition
To minimize cost
What does the dry cow diet consist of
Corn silage base = 15lb corn silage and 25 lb grass hay
or
hay/pasture base = 38 lb grass
2lb energy supplement
1 lb protein supplement
When is the dairy cow “transition” diet given
In the final 21 days of gestation
What does the transition diet consist of
25 lb corn silage
9 lb grass hay
5 lb grain
3.5 lb alfalfa hay
2 lb soybean meal
1.5 lb mineral and vitamin supplement
1 lb whole cottonseed
What are the goals of the transition diet
-Adapts the rumen to processing a greater nutrient load
-Ensures controlled change in the ruminal microbrial population
-limits digestive upset
-full adaption from a forage diet to a 50% grain diet in 5 weeks
What are the diet specification for transition diet
A decrease in certain dietary cations and an increase in dietary anion. (DCAD balance)
-increase in anions creates mild metabolic acidosis which triggers Ca and P mobilization from bone
-reduces incidence of hypocalcemia
-urine pH most widely used indicator of DCAD balance
If pH less than 6.0 then low risk for milk fever
If greater than 7.6 high risk for milk fever
What are the critical nutrients during “lactation nutrition” and describe why they are critical
- water = milk is 85-88% water
-energy = balance between fiber and NFC intake. Fats and oils are used also to increase energy density
-protein = metabolizable protein. RDP/RUP
-mineral = P, Ca, Se, Mg, K
What are some challenges of energy nutrition
Thin cows = lesser peak milk, poor reproductive performance
Fat cows = prone to metabolic disease in subsequent lactations
What nutrients are important in energy nutrition
Carbs = starch and fiber which is difficult to get right
Lipids =oilseed, dietary fats, rumen protected fats
What protein nutrition is top priority and which comes in second
Ruminally degradable protein (RDP): microbial requirements are top priority = maximize MCP production
Ruminally undegradable protein (RUP) needs are secondary. (Heat treated soybean meal and fish are preferred spruces and some sources can decrease protein flow to the SI)
How is protein status in lactating cows measured
Via MUN or milk urea nitrogen (10-16 mg/dl). Which indicated over or under feeding protein.
High MUN = CP too high, NFC too low, CP and NFC not available at same time.
Low MUN = CP too low
What causes acidosis
-highly fermentable grain consumed
-low pH of rumen encourages lactic acid production
-accumulation of lactate leads to low pH less than 5.2
-reduced gut motility, absorption, increase lactate and VFA in bloodstream: systemic acidosis and heart failure
What causes urinary calculi
And imbalance of Ca:P
What causes polioencephalomalacia (feedlot polio, brainers)
Excess sulfur, insufficient thiamine
Explain metabolizable protein (MP)
-can be supplied by feed or by microbial cell protein
-RDP and non-protein nitrogen are used to manufacture microbial cell protein
-no accurate estimation of AA requirements in dairy cattle (lysine and methionine generally considered most limiting AA)
What are some important macrominerals
Calcium
Phosphorus
Sodium
Chlorine
Potassium
Magnesium
Sulfur
What are some important trace minerals
Copper, zinc, selenium
Copper is the most common cause of toxicity at 4x the amount.
What are the maintenance requirements in sheep and goat
-wool growth
-high DMI
-multiple births
(Sheep = 2.5-3.5%. Goats = 3.0-5.0%)
-seasonal markets
What are the production goals for sheep and goats
Meat (speciality markets)
Wool
Dairy (fastest growing)
Pasture management
Lifestyle
How are sheep and goats fed
-range or pasture based production common (max use of quality forage during periods of peak nutrient requirements)
-they are used for noxious weed control because of selection preferences
When do we supplement sheep and goat feed
Flushing
Mid/late gestation
Lactation
Creep feeding
What is nutritional flushing
Elevating plane of nutrition prior to breeding (seasonally polyestrous)
Starts 2-4 weeks prior to breeding
What are the benefits of nutritional flushing
Boost ovulation rate
Improve conception and embryo implantation
Increase proportion of females in estrous
Can boost lambing/kidding rates by 10-20%
What are gestations lengths for sheep and goats
Sheep = 147 days
Goat = 152 days
-early gestations =day 0-50
-Mid gestations =day 50-100
-Late gestation =day 100-150
What are the nutritional needs during early mid and late gestation for sheep and goats
Early = slightly higher
Mid = slightly higher than early gestation goal is to maintain BCS and sustain pregnancy
Late = fetal growth is highest
Nutritional status should increase by 20%
Metabolic issues can occur with bag management
What is pregnancy toxemia
-Occurs in late pregnancy (older females, multiple fetuses, extreme fat/thin animals.)
- inadequate energy intake leads to hypoglycemia.
-dull, depressed
-grinding of teeth
-severely weak
What vitamins do sheep need
A D and E
(B and K are synthesized in the tunnel)
Where can sheep get vitamins A,D, E
D= green pasture forage and sun cured hay
E=grains and harvested forages contain variable amount. Closely related to selenium
(Selenium deficiency = white muscle disease)
What happens if a sheep is deficient in vitamin B
Polioencephalomalacia (polio or PEM)
-high sulfur intake (corn by products)
-destructions of neurons and brain swelling
(Blind, dilated pupil “star gazing”
What is the recommended Ca:P ratio
2:1 can tolerate 7:1.
Get from forages:grains
Explain urinary calculi
Ca:P imbalance
-formation of stones in urinary bladder that lodge in urethra (primarily impacts castrated males)
-high concentrate diet
-straining and dribbling urine
-water belly
-ammonium chloride
Symptoms of sulfur deficiency
Loss of appetite
Reduced gain
Reduced wool growth
What is sulfur Toxicity
Causes Se retention and leads to polio in lambs.
Excess can be from:
Excess sulfur intake water source
Distiller grain
And cheap protein and energy supplements
When it comes to copper how are sheep and goats different
-Sheep should not take in more than 25ppm
-Requirements for sheep are influenced by dietary sulfur and molybdenum (form insoluble complexes with copper reducing absorption)
-goats are not as sensitive to
What is copper toxicity
Sheep have excess copper in liver and it leaks into the bloodstream.
Causing massive blood cell destruction, severe anemia, jaundice and death in 24-48 hours
