Exam 1 Flashcards

Question

What factors affect nutrient requirements of cows?

Answer 1

* Stage of production * Calving to breeding (70-85 d PP) * Lactation; BCS * Breeding to weaning (120 days) * Mid-gestation (100 d) * Good time to gain BCS * Late gestation (60-70 d) * Cow Age * 1st Calf Heifers are still growing * (additional growth requirement) * Consider sorting, managing younger cows separately

Answer 2

* climatic factors * temperature * wind speed * humidity * precipitation

Answer 3

For every 1° drop in wind-chill temperature below 20 °, feed requirements are increased by 1% * Example: * Wind chill is -10°F * Degrees below Lower Critical Temperature are: * [20 °F - (-10°F)] = 30° * Cow needs 130% of her requirement to maintain weight * (Approximately 6 lb of feed)

Answer 4

* Decisions made during the cow’s pregnancy impact health and performance of the calf * Quality grade and eating quality may also be impacted * Heifer fertility and cow longevity also impacted * One of many factors that influence feedlot performance and carcass merit

Answer 5

* voluntary * producer driven * quality control program * educational training to build producer awareness * based on recommended national guidelines and research * **protecting consumer confidence in beef**

Answer 6

mating of sires of one breed to dams of another breed (or breed combination)

Answer 7

* Generates hybrid vigor * Heterosis * Also known as “hybrid vigor” * Increase in performance of hybrids over purebreds * Generates breed complementarity * Mate sires strong in paternal traits to dams strong in maternal traits * Paternal traits = growth, carcass merit, etc. * Maternal traits = reproduction, milk, etc.

Answer 8

* Associated with an increase in performance * Result of a recovery from effects of mild inbreeding * Measured as difference between average performance of crossbreds and the average performance of purebred parental lines * HV can result from having crossbred progeny, crossbred dams, and crossbred sires * “Additive”

Answer 9

* HV_I = HV for direct component of the trait * Crossbred progeny * HV_M = HV for the maternal component of the trait * Crossbred dams * HV_P = HV for the paternal component of the trait * Crossbred sires

Answer 10

* Losses can occur in: * HV^I * Progeny is crossbred, but there is breed overlap between individual’s sire and dam * HV^M * Dam is crossbred, but there is breed overlap between her sire and dam * HV^p * Sire is cross bred, but there is breed overlap between his sire and dam

Answer 11

1. Rotational Systems 2. Terminal Sire Systems 3. Composite Systems

Answer 12

* HV^I and HV^m * Breed complementarity – possibility for use of specialized sire and dam lines * Source of replacement females – produced within the system or supplied from elsewhere * Ease of management * Uniformity of progeny

Answer 13

* Rotations and composites are most suitable for species with low reproductive rates. * Rotations are often chosen if introduction of disease is a major concern. * Specifics are best if breed complementation is important. * Specifics or composites are also best if a particular breed is much better than others (adapted to a particular environment).

Answer 14

* 1862 – First Morrill Act. * Introduced by Justin Morrill, * Signed by Abraham Lincoln, * Created the land grant university system, granting to each state 30,000 acres of public land for each senator and representative. * Proceeds from the land sales were used to build the first land-grant universities

Answer 15

* 1887- Hatch Act. An act that established the Agricultural Experiment Stations in connection with the land grant colleges. * 1914- Smith-Lever Act. Act that established the Cooperative Extension Service and specified that the service would be associated with the land-grant university system.

Answer 16

* Cooperative – Funded by Federal (USDA) State, and Local governments * Extension – Designed to “extend” research information to state constituents * Service – Intended to serve the predominantly rural (at that time) agricultural communities.

Answer 17

Residual Feed Intake * Analysis of how much feed average animals requires to produce at average levels of performance * Some animals eat more than expected for their level of production and have positive residual feed intake (RFI) * Others (desirable animals) eat less than expected, having negative RFI

Answer 18

* A measure of the relationship between heredity (genotype) and how well those traits are expressed (phenotype). * An estimate of how effective genetic selection for a trait will result in a phenotypic/production improvement.

Answer 19

* A genetic correlation provides information on whether two heritable traits share genes. Correlation values range from 1.0 to -1.0 * Genetic correlations are classified by the strength of the relationship (low from 0 to ±0.2, moderate from \> ± 0.2 to ± 0.6, and high \> ± 0.6 to ± 1.0) between two traits and its directionality

Answer 20

* Positively correlated traits: * Most growth traits (WW/YW) * Negatively correlated traits: * Fat Thickness and REA * Need to pay attention to these correlations: * WW&YW highly correlated with Mature Size

Answer 21

* To make as perfect, effective or functional as possible. * As productivity moves toward an optimum level, profitability increases. * Avoiding extremes in biological type, enhances flexibility.

Answer 22

Expected Progeny Differences * Prediction, or expected difference between the progeny (offspring) of a selected sire, and the herd or group average for that selected trait * **an indication of the amount of genetic merit that the animal will pass to its offspring** * Attempts to answer “how much improvement can I expect from this sire?

Answer 23

* EPDs are calculated using: * The animal's own performance records * The performance of ancestors * Performance of half and full sibs, * Performance of progeny. * GE EPD’s include genetic testing information * EPD’s are the single best estimate of the animal's genetic merit for the trait because all known information on the animal and all of its relatives are used in the genetic evaluation procedure

Answer 24

* Direct EPD’s * Predict traits of the sire * BW, WW, YW, Scrotal Circ * Maternal EPD’s * Predict traits of the sire’s daughters * Maternal calving ease, milk, maternal weaning

Answer 25

* Calving Ease Direct (CED) * Is expressed as a difference in percentage of unassisted births, with a higher value indicating greater calving ease/ * It predicts the average difference in ease with which a sire’s calves will be born when he is bred to first calf heifers.

Answer 26

* Birth Weight EPD (BW): * Expressed in lbs, is a predictor of a sires ability to transmit birthweight to his progeny * Weaning Weight EPD (WW): * Expressed in lbs, is a predictor of a sire’s ability to transmit weaning weight to his progeny * Yearling Weight EPD (YW): * “ “ “ . . . Ability to transmit yearling weight.

Answer 27

* Residual Average Daily Gain (RADG): * Expressed in lbs/day, predictor of progeny performance given a constant amount of feed. * Yearling Height EPD (YH): * Predictor of progeny’s yearling height, in inches * Scrotal Circumference EPD (SC): * Expressed in cm, predictor of yearling scrotal size. * Docility (Doc): * Difference in temperament, higher value being more favorable.

Answer 28

* Heifer Pregnancy EPD (HP): * Reported in percentage units, the chance of a sire’s daughters becoming pregnant as first calf heifers. * Calving Ease Maternal (CEM): * Difference in percentage of unassisted births with a higher value indicating greater calving ease in first calf daughters. * Maternal Milk EPD (Milk): * Predictor of a sires genetic merit for milk and mothering ability as expressed in a sire’s daughters * \*That part of weaning wt attributed to milk and mothering ability

Answer 29

* Mature Weight EPD (MW): * Expressed in lbs, predictor of the difference in mature weight of daughters of a sire * Mature Height EPD (MH): * Expressed in inches, the predictor of the difference in mature height of a sire’s daughters. * Cow Energy Value ($EN): * Expressed as $ savings/cow/year. Components in calculation include lactation energy requirements (Milk) and energy costs associated with differences in mature cow size (MW and MH).

Answer 30

* Carcass Weight EPD (CW): * Expressed in lbs, predictore of the differences in progeny hot carcass weight. * Marbling EPD (Marb): * Expressed as a fraction of the differences in USDA marbling score of a sire’s progeny. * Ribeye Area EPD (RE): * Expressed in sq. in. - estimate of progeny REA * Fat Thickness EPD (Fat): * Expressed in inches – estimate of progeny 12th rib fat thickness

Answer 31

* $QG – Quality Grade value * Related to the increased revenue associated with improved quality grade, for specialized producers (Marbling EPD) * $YG – Yield Grade Value * Represents the yield grade portion associated with $G. Multi-trait, ribeye, Fat thickness and weight. * $B – Beef Value * Index value expressed in dollars per head, is the expected average difference in future progeny performance for postweaning and carcass value compared to progeny of other sires.

Answer 32

* Stayability - probability that a bull’s daughters will still be in the herd at 6 yrs. of age - strictly calving data records * Heifer pregnancy rate - probability that heifer progeny will conceive and calve as a 2 year old. * Cow Maintenance - average amt. of feed required - relies on mature wt. and milk production.

Answer 33

* BMI – Baldie Maternal Index - is a maternally focused index that has a production system based on H x A females * CEZ- Calving Ease Index – combines CE and MCE EPD’s * BII – Brahman Influence Index – designed for Brahman X Here crossbred herds * CHB- Certified Hereford Beef – carcass focus

Answer 34

* Use across-breed EPD’s to evaluate bulls from different breeds * Allows you to maintain uniformity in a cross breeding system

Answer 35

* What does my operation produce best? * What traits would complement my current cow herd? * What are some realistic goals? * Operation Goals: Grazing Management, Cost of Production, Feed Usage, Pregnancy Rates, etc. * What do I produce best: Weaned Calves, Yearlings, Bred Heifers, Cull Cows, Backgrounded Steers, Replacement Heifers, etc. * Marketing opportunities: grass-fed, natural, lean, high marbling,etc.

Answer 36

* National Beef Quality Audits point to several concerns * Low Overall Uniformity & Consistency * Inadequate Tenderness * Low Overall Palatability * Insufficient Flavor * Excessive Weights of Cuts * Low Overall Cutability

Answer 37

* For bales, be sure to use a hay probe/sampling tool * Important to sample inside of the bale (not just the outside) * 10-14 samples per lot * ”Lot” – any group of bales under similar management (cutting, field, purchased hay, etc.) * Any feed that you have concerns over.

Answer 38

1. Water (most important nutrient to measure 2. Proteins (C, H, O, + N 3. Energy 4. Minerals 5. Vitamins

Answer 39

* Water (most important nutrient to measure) * Dry Matter (DM) * DM requirement? * Need to account for moisture when evaluating/comparing feedstuffs * Functions * metabolic reactions, transport of nutrients, maintain normal body temperature, physical shape

Answer 40

* Proteins (C, H, O, + N) * Contain 16% N * N% x 6.25 = % protein * Ruminally degraded (RDP) vs. bypass (RUP) * Amino acids * Contain amino group (NH2) * Various combinations of some 25 AA’s * Most expensive nutrient per unit

Answer 41

* Acid Detergent Fiber * the amount of dry matter digested is a function of the level of ADF in forage and is expressed as a percentage * Neutral Detergent Fiber * As NDF increases in forages, animals eat less

Answer 42

* carbohydrates (C, H, O) * Starch, sugars (simple) * Cellulose (cell walls - complex) * Fats & oils (lipids) * More C & H in relation to O * 2.25 x more energy than CHO * Functions of essential F.A.’s * Precursors of prostaglandins (PGF2a) * Structural components of cells

Answer 43

* Total Digestible Nutrients * Estimate of the total digestibility, and therefore the ENERGY value for the feed. * TDN used in forage based (range) diets * Net Energy System used more in confinement feeding programs * NDF and ADF values used to calculate TDN

Answer 44

* The percentage of a nutrient that is absorbed from the digestive tract * Energy evaluation of feeds (TDN vs. NE) * TDN = Total Digestible Nutrients * (Dig. CP) + (Dig. Crude Fiber) + (Dig. NFE) + (Dig. Crude Fat x 2.25 * Overestimates energy in roughages * Net Energy * Measures energy in Mcals/lb or kg * Energy allocations for specific uses (more accurate)

Answer 45

* TDN system often used for cow diets * NE system generally used for feedlot diets * More accurate * Less variation in nutrient analysis of concentrates

Answer 46

* A way of comparing energy values between forages * Primarily used to compare alfalfa samples, * Used primarily for pricing alfalfa hay, not used in ration balancing

Answer 47

* An additional way of comparing forages. * Uses NDF and ADF values, as well as in- * vitro digestibility values * More accurate estimate of forage quality * Not used in ration balancing

Answer 48

* Elements other than C, H, O, & N * Inorganic (no C) * Macro (Ca, P, Na, Cl, Mg, K) * Micro or trace * Zn, Cu, I , Mn, Co, Se * Mo, S, Fe

Answer 49

* Fat-soluble (A, D, E, K) * Water-soluble ( C, B-complex)

Answer 50

* Forage Analysis * Allows you more efficiently utilize feedstuffs * Can more effectively supplement nutrients when needed (cost effective practice) * Estimating intake * Factors affecting intake * cow size, milk production, BCS, forage quality, amount & type of supplement

Answer 51

* Roughages/Forages * \>18% crude fiber * Relatively low in TDN * Concentrates * Energy feeds * \< 18% C. Fiber and \< 20% CP * Protein supplements * \> 20% CP * Supplementation vs substitution

Answer 52

* Self - fed supplements * Variation in intake * Expensive * Daily, limit fed * Minimize competition * Frequency of supplementation * Protein * Can offer as few as 3X/wk. (if all natural) * Need to provide the entire weeks requirement in those 3 offerings. * Cost effective * What physiological process allows this to work? * Energy * Must feed daily * Why?

Answer 53

* Determine cost of specific nutrient you are buying * Determine DM content * Know nutrient content of feedstuff * Determine price per pound of nutrient

Answer 54

* Typically hay that was baled or stacked too wet * Fermentation within the bale leads to very high temperatures (above 150 degrees) * Caramelization or browning occurs * “Mailliard Reaction” * Lab analysis still measures crude protein, but that protein is unavailable to the animal * N has become chemically inked to CHO and then doesn't contribute to DIP or UIP

Answer 55

* Micotoxin: toxic secondary metabolite produced by a fungal organism (mushrooms, molds and yeasts) * Molds commonly found in hay are: * Alternaria * Aspergillus * Cladosporum * Fusarium * Mucor * Penicillium * Rhizopus * Feed labs typically test for grain micotoxins * Aflatoxin, vomitoxin, etc. * Overall mold count may be helpful * Be sure to sample several bales to get a general indication of the severity of mold

Answer 56

* Cattle can tolerate higher levels than most domestic species * Ruminal microbes destroy a high percentage of micotoxins * Horses, swine very susceptible * Pregnant & Lactating cattle most susceptible * Lower risk with feeders and non-pregnant animals * **Feeding recommendations** * Few tests measure predominant forage micotoxins * Overall micotoxin/mold count may help * Dilute and blend when possible * Feed in well-ventilated areas * Feed with silage or other wet feed to minimize dust exposure * Monitor intake when possible, watch for reduction in intake due to micotoxins * Consider selling to feedyard * Safest to feed to yearlings, non-pregnant animals * Highest risk are pregnant animals, stressed and weakened cattle * Consider selling to your neighbor 😀 , local feedlot

Answer 57

* Nitrates are converted to NITRITES in the rumen * Nitrites bind to hemoglobin, creating methemaglobin * Blood loses it’s O2 carrying ability, leading to lack of oxygen delivered to tissues * Since the fetus has a high O2 requirement, an early symptom is asphyxiation of fetus leading to abortion * Plants accumulate Nitrogen in the root and lower portion of the stalk, in preparation for growth. * Stressors that limit growth, such as drought, hail, frost, etc. lead to an accumulation of nitrate in the plant * Heavy soil fertilization will also contribute to overall forage nitrate levels. * Species include annual grasses and cereal grains such as oats, sudan, millet, etc. * Pigweed, kochia, lambsquarter all accumulate N.

Answer 58

* Be sure to test any susceptible forage for Nitrates – especially sensitive crops * If Nitrates are high: * Feed to non-pregnant animals if possible * Blend, dillute with low Nitrate feeds * Work cattle up slowly on higher nitrate feeds ◦ Supplement with grain to reduce risk * Watch feeding management closely * Make sure animals do not over-consume susceptible feeds * Watch weather patterns * Feed consistently and accurately (minimize variation)

Answer 59

* Pregnancy abortion * Signs of low blood oxygen: * Drooling * Staggering, lack of coordination * Weakness, lethargy * Move cattle calmly, slowly * Provide adequate water and safe feed * Allow cattle to regain O2 levels

Answer 60

* Test all suspect forages before feeding. * Keep overall ration nitrate level below 6,000 PPM. * Feed a balanced ration with adequate energy. * Introduce high nitrate feeds gradually. * Feed low nitrate forage or grain first, or tub grind and blend. •Feed frequently, don’t allow cattle to go hungry. * Make sure water supply is low in nitrate. * Feed adequate Vitamin A – 30,000 IU/day. * Be cautious during severe weather.

Answer 61

* 1926 - First official USDA standards for carcass beef * Why? * Uniform reporting of dressed beef * Quality of beef – Armed forces WWI, hospitals

Answer 62

* Aid to Livestock Producers * Provides Uniform Supply * Assists in Marketing and Promotion * Permits Useful Price Reporting * Provides Industry Feedback * Provides info on meat tenderness, juiciness, and flavor. * Determines value of live cattle and beef.

Answer 63

* quality (palatability) * yield (cutability) * combination

Answer 64

Quality grades (attempt) to reflect the flavor and tenderness of meat and are primarily determined from carcass maturity and the amount of fat within the meat (i.e. marbling or intramuscular fat).

Answer 65

1. prime 2. choice 3. select 4. standard 5. commercial 6. utility 7. cutter 8. canner

Answer 66

1. steers 2. heifers 3. cows 4. bullocks 5. bulls * Steers and Heifers are eligible for all 8 quality grades * Cows are eligible for all quality grades except Prime * Bullocks are eligible for Prime, Choice, Select, Standard, and Utility * Bulls are not eligible for a quality grade

Answer 67

* A - 9 to 30 Months * B - 30 to 42 Months * C - 42 to 72 Months * D - 72 to 96 Months * E - More Than 96 Months

Answer 68

* Evaluating the size, shape, and ossification of the bones and cartilages , and the color and texture of the lean at the ribeye * the more ossified, the older the carcass * Dentition * on the kill floor, looks at the number of deciduous teeth present * Age records – verified by USDA * requires strict records; damn and calf info, calving date, sex, RFID tag

Answer 69

moderately abundant- average prime * USDA Prime: Prime grade beef is the highest quality grade, hopefully with the greatest likelihood of, juiciness and flavor. It has abundant (AB) to slightly abundant (SLAB) marbling -- flecks of fat within the lean -- which enhances both flavor and juiciness.

Answer 70

Slightly abundant, low prime * Approximately 5 to 6% of fed beef grades low prime or better.

Answer 71

Moderate, high choice * USDA Choice: Choice grade beef has less marbling than Prime, but is of very high quality.

Answer 72

Modest, average choice

Answer 73

1. Predominantlyblackhaircoat 2. Minimum of Modest 0 marbling, (MT 0 ) 3. Mediumorfinemarblingtexture 4. Cattle\< 30 MOA 5. 10 to 16 sq. in. REA 6. \<1,051 lb carcass 7. \<1 inch BF 8. Superior muscling (nodairy) 9. No dark cutters or blood splatter 10. No evidence of neck hump exceeding 2” (excludes bos indicus)

Answer 74

small, low choice

Answer 75

USDA Select: USDA Select grade beef is leaner (less IMF) than USDA Choice beef

Answer 76

* (Live) – 51% whiteface, Hereford and Hereford * English crossbred cattle * (Carcass) Enrolled in CHB program prior to harvest * USDA Select Choice or higher (Jan. 1, 2019) * A maturity only * No noticeable hump (2” or less) * No dark cutters or blood splash * No dairy influence

Answer 77

* Carcass factors used to calculate yield grade * Adjusted fat thickness * Percentage of Kidney, Pelvic and Heart Fat (KPH) * Rib Eye Area * Hot Carcass Weight

Answer 78

The longissimus muscle is measured at the 12th rib by using a grid expressed in square inches, or a compensating polar planimeter, which measures a rib eye tracing Rib eye area is an indicator of carcass muscling; as rib eye area increases, retail cut yield increases.

Answer 79

* Two certainties * Animals require minerals for production * Mineral nutrition is complex and not well understood * Availability of minerals from feeds * Actual requirements of animals * Impacts of environment/performance on req.

Answer 80

* Objectively analyze production * Rule out other factors * Determine mineral supply * Forage, supplement, and WATER * SAMPLE, SAMPLE, SAMPLE!!

Answer 81

* Phosphorus is generally the most expensive mineral to supplement * Use forage analysis estimates of Phos and Calcium * Using conservative intake (2 - 2.5% of BW, or 24 - 30 lbs), estimate phos intake * Include additional phos sources, such as supplements and mineral * Compare Phos supplied vs. requirements

Answer 82

* Collagen Formation * Pigmentation * Antioxidant * Hormonal Function * Component of Enzymes • Enzyme Metabolism * Enzyme Activity * Wound Healing * IMPORTANT FOR IMMUNE RESPONSE

Answer 83

* Copper (Cu) (requirement 10 ppm) * Involved in numerous functions: * hemoglobin formation * iron absorption * connective tissue metabolism many enzyme functions * Forage levels often marginal (\< 7 ppm) * Negatively interacts with Mo, Fe & S * Want Cu:Mo ratio 4.5 or greater * Problems when S exceeds .25% of diet * Problems when Fe exceeds 350 ppm * Liver is the tissue of choice * \< 25 ppm wet weight indicates def. * Evaluate feed & water sources for antagonizing minerals

Answer 84

* Involved in many functions: * cell growth * immune function * keratinatious tissue growth (hooves) * Forage levels are often deficient * Requirement (NRC 96) = 30 ppm * Average of 17.2 ppm in native forage in Great Plains Region (CHAPA, 1996) * High levels of Ca & P will interfere with Zn * High milk production increases need for Zn * Deficiencies are associated with: * reduced bull fertility (Ansotegui et al., 2003) * delayed puberty * abnormal estrous behavior * reduced cow fertility

Answer 85

* Primary Deficiency * Caused by inadequate dietary mineral intake * Secondary Deficiency * A factor interfering with mineral absorption and/or metabolism (ie. Moly, Sulfur, Iron)

Answer 86

* Animal requirements * Minerals in feeds and forages * Analyze The Water!! * Potential antagonists * Sources and levels

Answer 87

1. Produce low-cost/high-profit cattle that: 1. Products (calves) are in demand 2. Beef produced is highly palatable 3. Females are suited to unique production environment 2. Manage available resources 1. Maximizing net profit, while conserving and/or improving 3. Quality of Life / Commitment to Family 4. Leadership/involvement in community 5. Active participation in industry

Answer 88

* Production/Enterprise Goals * Reduce cow costs by $10/cow/year each of the next 5 yrs. * Reduce weaned calf breakeven price by $.10/lb/year * Land Resource Goals * Improve stocking rate by X% by improving grazing management and grazing distribution * Family / Quality of Life Goals * Mandatory vacation, regular family meetings, group activities * Community and Industry Involvement Goals * Attend local stockgrower’s meetings, etc.

Answer 89

1. Age of calf at weaning 2. Daily gain from birth 3. Genetic growth potential 4. Use of Implants 5. Milk Production of dam

Answer 90

* Number of calves weaned / Cows exposed to A.I./bull * Breeding percentage * Calving percentage * Weaning percentage * Factors involved? * Bull fertility, nutrition, A.I. success, vaccination program, pre- and post- breeding management, cattle type,

Answer 91

1) Heifer development 2) Breeding program for heifers 3) Feeding heifers 4) Calving ease 5) Post-partum interval

Answer 92

1) Age of calf when weaned 2) Calving season 3) Use of growth implants 4) Feed supply 5) Genetic selection 6) Heterosis 7) Overall herd health

Answer 93

1. Enterprise budget 2. Biological type of cows: * Puberty * Calving Ease * Milk Production * Mature weight * Rebreeding * Longevity 3. Managing Feed Costs

Answer 94

1. Increasing cow numbers 1. improving grazing distribution 2. cow size 3. cow efficiency

Answer 95

* enterprise budgets * using sound financial decisions * doing what best works for your individual operation

Answer 96

* A way of choosing between two operation decisions 4 parts to a partial budget * Increased Costs, Decreased Costs * Increased Revenue, Decreased Revenue * These are ideal for short term decisions, but can be used for long term

Exam 1 Flashcards

(120 cards)