Midterm 2: Beef 2 Flashcards
what is the main purpose behind stocker/backgrounding programs?
to more evenly distribute supply into the finishing phase, so not every animal is going to finishing programs at once
what type of diet is usually fed (in general) at stocker/backgrounding?
high forage diets, anywhere from 50 to 70%
why is a stocker program especially good for small frame breeds?
it allows them more time to grow, to increase lean and skeletel growth before going to finishing
animals usually stay in stocker programs until they weigh how much?
300 to 400kg, then they go to finishing
what is “program feeding” in regards to stocker programs?
may be done when forages are too expensive and cows may be fed restricted higher grain diets, the feed is limited, diets are formulated to acheive expected gains, and promotes easier adaptation to finishing diets. it is resitrcted because we dont want the cows to finish too soon or too small
how does the quality of forage change as it grows and mature?
as it grows and matures the quality and digestibility decreases
what is the relationship between animal output and pasture stocking rate
there is an optimal zone that balances animals per acre and animal output, you dont want animals to over graze or undergraze
what are the benefits of rotational systems?
if cows are all in one pasture, there will be some over grazed and under grazed areas, but if there are many different areas, this doesn’t happen, and daily gain has to potential to go up
what is a rest period and why is it important?
rest of the pasture means no animals are grazing it, it allows the pasture to recover
why would you want to use pasture supplementation?
it can increase daily gain by 0.3 to 0.45 kg per day, can be useful for in bad forage years/seasons
what (in general) is the type of feed during the finishing phase?
- high energy diets mostly grain and small forage amounts, some by product feeds, vitamins and minerals, fed as a TMR
finisher phase diets are formulated to:
- increase growth rate
- increase feed efficinecy
- increase animal health
- increase carcass quality
- decrease cost of gain or maximize profit
cattle in finishing phase should be fed to attain carcass composition desired by the market, which is what % fat?
28-29% body fat
feedlot/finishing diets are split into 3 sub phases/diets which are:
- receiving ration
- step up phase (slowly increase amount of concentrate)
- finishing
animals coming into the feedlot are placed on a receving diet and then are adapted to the higher grain diets over _______
21 to 28 days
final finishing diets will contain what percent concentrate, CP, and urea?
80 to 95% concentrate, 13.5% CP and up to 1% urea
what are the most common grains and protein sources
grains: barley, wheat, corn, wet and dry distillers grains, alternative by products
protein: distillers grains, manola meal, soybean meal, sottonseed meal, sunflower meal
what percent of a feedlot finishing diet is forage and what kinds of forages are usually used?
9-10%
small grain silages, corn silage, or alfalfa
ionophores are fed to feedlot cows. why?
it increases feedefficinecy and makes the cows eat smaller more frequent meals to help prevent acidosis
cattle sometimes are moved from weaning straight to the finishing diets. when is this a good idea?
works better for larger framed breeds, small frame breeds may promote finishing weights that are too low. these cows will have earlier and more rapid fat deposition
why are newly weaned calves subject to severe stress? why is this a concern?
confinement, handling, shipping, mixing, and treatment
stress reduced appeite, promotes poor immune response, and increases morbidity and mortality
lightweight calves being started at the finishing feedlot are fed what kind of diet?
usually 50 to 70% roughage to allow time to adjust and get used to bunks and conentrates, can also be given free chooce hay to stimulate eating
true or false: there is no standard nutrition program across feedlots
true, the diet fed to incoming cattle and protocol of moving them to the finishing ration are dependent on the goals and management of the feedlot operator
what is the receving diet? how is it usually presented?
the diet fed to calves upon entering the feedlot, may be free choice hay in a bunk or a forage:concentrate diet like 70:30
when cows first arrive at the feedlot and are put on a receiving diet, why is the hay placed near the waterer?
to teach the calves where the waterer is and get them to drink sooner which can be a problem sometimes for calves
what is a step up diet and what is the objective of set up diets?
a series of diets sequentially increasing concentrations of grain fed over a period of 3-4 weeks, eventually getting to around 85 to 95% concentrate with a decrease in protein
objective: minimize digestive disturbances like acidosis and bloat, allow rumen microbes to adjust, allow rumen epithelium to adapt, minimize feed intake fluctuations
how does a step up diet differ between yearlings from stocker programs and calves going straight to finishing feedlots?
yearlings step up faster than calves do
during a step up diet, how long are the animals eating each diet before moving to the next one?
usually 3 to 5 days on the diet before it chances to slightly higher concentrates
what are the 3 objectives of bunk feeding management?
- keep animals eating consistent amount of feed
- maximize animal preformance
- minimize giestive disorders
att cattle in the same pen must have:
equal opportunity to consume feed
when should feed be delivered? why?
at the same time every day to avoid digestive upset
what are the two feeding options in a feedlot?
- ad lib (higher feed wastage)
- slick bunk (most common)
describe what slick bunk feeding is. What two things is it associated with?
the feed intake is regulated BUT not reduced, there may be a short absence of feed like 30 mins or less
associated with:
- improved performance
- reduced sorting of ingredients and less feed wastage, improved feed efficinecy
how many times a day are cows fed at a feedlot, and when bunks are checked, how much feed should be left prior to the next day’s feeding?
twice a day
bunks should only have crumbs but SHOULD NOT BE EMPTY!
if you see that the bunks are empty at the end of the day, what should you do?
make changes for the following day but make changes small and slow
_______ leads to sustained growth
steady intakes
describe the process of bunk reading at a feedlot
done to determine the amount of feed that needs to be put in the bunk, bunk is read between 4:30 and 5, and by 7 the bunks should have only crumbs left. feeding starts at 7:30, and there are two feedings, 40% in am and 60% in the pm. From there you can increase or decrease the amount fed by 2.5 to 5%. Adjustments amy also be made according to the weather
which forms first and which forms last: muscle, fat, bone
bone first, then muscle, then fast
what is important to remember about deposition in beef cows?
fat is depositied later in the cow’s growth, so cows need time for this to happen
list the areas of fat deposition from earliest to latest. why is this important to consider?
periernal, intermuscular, subcutaneous, intramuscular. If we want marbling, we have to feed animals for longer since intramuscular is the last to deposit
as the animal grows, what things increase and what things decrease?
- DMI per day increases (dry matter intake)
- energy requirement increases
- crude protein requirement decreases
- calcium requirement decreases
- phosphorus requirement decreases
describe what kind of fat you will see depositing when you have lots of:
- acetate
- glucose
acetate: mostly subcutaneous fat
glucose: mostly intramuscular (which is what we want for marbling)
true or false: at the same BW, larger frame animals will have lower fat
true!
true or false: small and large frame breeds can be finished with equal fatness but not at the same body weight
true
which do you need to feed for longer in order for the right amount of fatness to develop: small frame breeds or large frame breeds?
large frame breeds
what are the effects of implants on growth?
they increse body fat and weight, so it can make an animal more of a larger frame
what is compensatory growth? what is it associated with?
the ability to recuperate or recover after periods of underfeeding
associated with higher than normal rates of growth, lower maintenance requirements, and higher DMI than in other cattle
what are some factors that can effect compensatory gain?
- age of the animal during feed restriction
- severity of the feed restriction
- duration of feed restriction
- feed quality post restriction
list a few high risk and a few low risk grains for acidosis
high risk: dry rolled wheat, steamrolled or dry walled barley, high moisture corn
low risk: dry whole corn, dry rolled sorghum, dry rolled corn
rumen acidosis is a balance between what two things?
acid production via fermatiation and microbes, and acid neutralization via buffering salivia and feed absroption
what is a processing index?
indicates how processed a grain is, the more processed the grain, the LOWER the processing index number
how do you measure processing index?
measure the bulk density of whle grain, and measure the bulk density of the processed grain
PI=wt processed/wt whole x100
which has a higher risk of acidosis, higher PI grains or lower PI grains?
lower PIs, because it means they’re more processed and more easily fermented
what is the difference between proper and poor rolling of grains, and how can poorly rolled grains cause acidosis?
properly formaed grain should result in uniform particles that are all the same size. poor rolling results in large and small particles that are not the same size. the “fines” are the small particles that can cause acidosis because they are easily fermentable
all processed barey and wheat should contain less than ____% fines for the prevention of acidosis
3
what is the relationship between fecal starch concentration and processing index of the grain?
the higher the PI, the more starch there is in the feces. This makes sense because a higher PI means it’s not as easily digestible so much will be lost in feces
what is the relationship between fecal starch concentration and gain to feed ratio
the higher the gain to feed ratio (meaning the cow gains more per kg of feed), the LOWER the fecal starch concentration, which makes sense because if they poop it out they can’t use it for GAINS
what are ionophores, how do they work, and why do we use them?
- inophores are feed additives
- they disrupt ionic gradient across bacterial membranes and reduced intracellular pH
- we give it to cows to prevent acidosis, improve feed efficinecym and reduce intake while keeping the same ADG
what is ractopamine and why do we feed it to cows?
- a feed additive that is similar to endogenous catecholamines
- a beta-adrenergic agonist that promotes muscle growth, increases skeletal muscle mass and increases protein synthesis, reduces protein degredation
- better response in steers than heifers
when is ractopamine fed?
at the end of the feeding period, last 28 to 42 days
true or false: cows often show signs of liver abscesses
false! cattle often do not show specific clinical signs with a liver abscess
what causes live abscesses in feedlot cattle?
they are secondary to acidosis and rumenitis in the rumen, inconsistent bunk management promoting acidosis can lead to a higher incidence of liver abscesses, can happen also due to rapidly increasing dietary energy thru high grain and low forage diets and irregular feeding
liver abscesses are higher in which: holsteins or beef?
holsteins
what is the economic impact of liver abscesses?
- reduce feed intake
- reduced weight gain
- decreased feed efficiency
- decreased carcass dressing percentage
- livers are condemned
what is Tylosin and when/why is it given to cows?
an antibiotic given in the feed, to prevent liver abscesses
what is the big problem we think about with grazing legume diets
frothy bloat
why do legume diets lead to bloat?
they ferment very quickly in the rumen, leading to excessive polysaccharides being produced which make frothy bubbles in the rumen
what is one big plant management strategy you can do to prevent bloat?
allow animals to graze on more nature plants
list some bloat causing legumes to be cocnerned about
alfalfa, sweetclover, red clover, white, clover, alsike clover, winter wheat
what is alfalfa:sainfoin and what are the pros and cons?
it is a feed additive that can reduce the incidence of bloat by up to 98% but it is very short acting
what are 3 big PLANT bloat risk factors?
- after a fall frost
- heavy morning dew
- immediately after rain
what are 4 big ANIMAL bloat risk factors?
- hungry cattle
- placing cattle out in the morning (dewy/wet)
- yearlings more at risk than cows
- unadapted grazing to alfalfa
what is Alfasure/Poloxalene and how does it work?
additive to control bloat, acts like a surfactant, delivered in the drinking water, it breaks down the exopolysaccharides on the bubbles and releases the gas
what is grass tetany? what are some clinical tests you can use to diagnose this?
Mg deficinecy usually associated with grazing of fast growing cool season grasses suring spring
check blood plasma or serum and urine values and concern should be if any of these fall below 15 mg Mg/mL. dramatic signs of tetany are clear at levels below 10 mg Mg/mL
what are some clinical signs of tetany?
nervousness, rapid breathing, aggressiveness, stiff gait, bellowing, muscle tremors, convulsions, hypersensitive to stimuli
grass tetany occurs most often in
older females in early lactation (higher requirement for Mg during this time)
grass tetany may be triggered by
a stressor such as cold weather
magnesium must be supplied daily because
it is excreted in milk and urine
high levels of what ion in the soil can inhibit plant ability to uptake Mg?
K, potassium
what is nitrate poisoning?
nitrate accumulates in plans due to excessive uptake of soil N, usually promoted by cool temperature, cloudy weather, drought, frost, etc
what is a major risk factor for nitrate poisoning?
soils heavily fertilized with N
what is the pathogenesis of nitrate poisoning?
excessive NO3 reacts with hemoglobin to form methemoglobin which prevents oxygen from being released into tissues and the animal dies of asphxiation
what are the clinical signs of nitrate poisoning?
- staggering, rapid pulse, frequent urination, dysnpea, collapse, coma, death
what role does microbial adaptation have in nitrate poisoning?
the rate and degree of NO3- reduction in the rumen depends on the microflora present and the amount of energy available, they need to be dapted to the higher levels of nitrate in order to deal with it
how is nitrate posioning treated?
methylene blue, it can turn methemoglobin back into normal hemoglobin. note animals should also be given an alternative forage source
what are some ways to manage and prevent nitrate poisoning?
test the feed, dilute high nitrate feeds, replace dry forage with silage, frequent feedings, gradual adaptation to questionable feed, only use N fertilizers if soil actually needs it (do soil testing)
