Improving Beef Cattle Performance: Breeding, Management, and Environmental Considerations, Slides of Biology

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Unit 10: Beef Cattle Docsity.com Objectives • Understanding of the approaches to improving cattle performance through feeding, environment, management, genetics • Knowledge of various management practices associated with cow/calf, feeder, and finishing • Discuss the role of environmental management in cattle feeding • Investigate the economic picture of the beef industry Docsity.com Introduction – Registration numbers • Angus, Limousin, Simmental, Hereford are the most common in regard to registrations – Breeds • http://www.ansi.okstate.edu/BREEDS/index.htm Docsity.com Oklahoma State University ce Doesity‘¢om  x Baduiy.boip | Docsity.com y i Doesitycom  , i _. ; - - bh ; de io : : : = a me (Bpvided by Dr. Robert Kropp Docsity.com Docsity.com Docsity ‘com Docsity.com Traits and their Measurement • Reproductive Performance – Goal of >85% of calves weaned – Calf every 365d or less – Entire herd calving season <90d – Fertility is not highly heritable (~20%) – High heritabilities for: • Birth wt. ~40% heritable • Scrotal Circumference ~40% heritable (>32cm) – Increased SC produce more semen – Half sisters that reach puberty earlier – Best way to improve reproductive performance is to improve environment Docsity.com Traits and their Measurement – What 2 ways can we improve environment? – Select bulls that are reproductively sound – Performance can also be improved by crossbreeding • Weaning Wt. – Measured by actual wt. • Reflects milking & mothering ability of dam • Preweaning growth rate – ww is commonly adjusted to 205d equivalent to account for variance in age of calf/dam – ww are commonly expressed as ratio to the h l i h Docsity.com Figure 25.1 Variation or differences in weaning weight in beef cattle. The variation shown by the bell-shaped curve could be representative of a breed or a large herd. The vertical line in center is the average or the mean, which is 410 lb. Note that the number of calves is greater around the average and is less at the extremely light and extremely heavyweights. Source: Colorado State University. Docsity.com Traits and their Measurement • Feed Efficiency – Lbs. feed/lb. gain – Can be misleading • Hard to measure • Differences in production goal – High heritability ~45% • Carcass Merit – Quality grades and yield grades – Can measure by ultrasound or by visual analysis – Highly heritable >30% Docsity.com Traits and their Measurement • Longevity – Important, especially for cows – Bulls may be kept 3-5 yrs. – Highly productive cows 4-15 yrs. – Reasons for culling • Skeletal unsoundness • Poor udders • Eye problems • Lost/worn teeth – Few cows highly productive >10yrs. Docsity.com Traits and their Measurement • Conformation – Form, shape, visual appearance – Source of controversy – Traits are medium to high heritability (30-60%) • Genetic Defects – Usually occur infrequently – Common defects • Double muscling – Slow growing, poor fat deposition • Syndactyly (Mule Foot) Docsity.com Bull Selection • Breeding Values – Phenotype determined by genotype + environment – Genotype determined by two factors: • Breeding value (what genes are present) • Nonadditive value (how genes are combined) – Values are collected and analyzed by computer by breed organizations • EPD’s are used to express these values Docsity.com Bull Selection • Sire Summaries – Data that has made sire selection much more accurate & effective – Published by most breed associations – Measurements by EPD’s and ACC (Accuracy) • EPD – Birth wt. – Milk – Weaning-growth – Maternal – Yrlg. Wt. Docsity.com Bull Selection – ACC » Measures expected change in the EPD as more progeny data is available » >.90 very little expected change » <.70 might change dramatically • Must be careful about stacking pedigrees Docsity.com Cow Selection • Select based upon their performance and the performance of their offspring & additional evidence that they can be productive if bred back • Measured by: – Pregnancy – Weaning/yearling wts – EPD’s of cows Docsity.com Crossbreeding programs for Commercial producers • Most producers travel w/in 150 mi to select bulls for natural AI – Must have knowledge of who has good genetics • Selection should be based on how each breed complements the other • Why is crossbreeding advantageous for commercial producers? Docsity.com Crossbreeding programs for Commercial producers • Most heterosis is expressed by weaning time • Two breed rotations – Ex. • Two breed rotation w/ a terminal cross – Ex. – All terminal cross calves are sold • Three breed rotation – Ex. Docsity.com Figure 25.8 Three-breed rotation cross. Females sired by a specific breed are bred to the breed of the next bull in rotation. This will increase the pounds of calf weaned per cow by approximately 20%. Source: Colorado State University. Docsity.com Figure 25.9 Two-breed rotation and terminal site crossbreeding system. Sires are used in the two-breed rotation primarily to produce replacement heifers. Terminal cross sires are mated to the less productive females. This system will increase the pounds of calf weaned per cow bred by more than 20%. Source: Colorado State University. Docsity.com Cow-Calf Management • Effective and profitable management of cow/calf operations is dependent upon manager’s ability to budget time to critical activities • Two goals of the operation – Generate profit – Provide opportunities for others • Finishing cattle • Club calves Docsity.com Figure 26.2 Annual cow–calf returns and cattle inventory. Source: Livestock Marketing Information Center. Docsity.com Management for Optimum Calf Crop Percentages 1. Feed heifers adequately to reach puberty @ 15 mos (650-850 lbs) 2. Heifers bred to calve early in season ◦ More likely to conceive early as 2 & 3 yr olds 3. Manage postpartum interval for heifers ◦ Return to breeding time ◦ May feed separately from mature cows 4. Monitor BCS ◦ Fat/thin cattle have more problems 5. Observe closely at calving to prevent dystocia (especially heifers) Docsity.com Management for Optimum Calf Crop Percentages 6. Manage birth weight – Critical balance between size of calf and dystocia rates • Heavier birth weights usually = heavier calves • Can also lead to problems 7. Evaluate bulls for soundness, fertility – Bulls can have low libido and/or low sperm counts – cow:bull ratio – 30:1 8. Crossbreeding can improve calf crop % by 8- 12% Docsity.com Management for Optimum Weaning Weights 3. Growth stimulants ◦ Increase weaning wts 5-15% ◦ Ralgro, Synovex C, Compudose, etc. ◦ Implanted as pellets under skin ◦ Don’t use on breeding stock ◦ Communicate with buyers for appropriate implant strategy  Can reduce grading and meat quality 4. Creep feed ◦ Can greatly influence weaning wt ◦ Also adds cost ◦ Best used under drought or marginal feed quality situations Docsity.com Management for Optimum Weaning Weights 5. Disease management ◦ Especially of the cow – reduces milk production and intake of calf 6. Genetic selection ◦ Select for milk production & weaning wt in replacement females ◦ Effective selection can result in a 4-6lb/calf/yr increase 7. Crossbreeding ◦ Avg 20% increase in weaning wts  Some increase due to reproductive performance, some heterosis  Crossbreds tend to wean more & heavier calves Docsity.com Management for Low Annual Cow Costs Adequate income/expense records should be carefully analyzed Studies show a range of $61/hd breakeven to $117/hd breakeven ◦ Contributes to major differences in profits/cow 5 ways low cost producers reduce costs 1. Reduce supplemental feed costs 2. Rotational graze 3. Genetics 4. Reduced labor 5. Strong herd health management Docsity.com Stocker-Yearling Production • Most common diseases: – Shipping fever – Other respiratory diseases • Maintaining a constant supply of high-quality forages is key to profits Docsity.com Types of Cattle Feeding Operations • Commercial Feedlots – Typically >1000 hd – Owned by individual, partnership, corporation – May own cattle, or feed cattle owned by others • Feeders • Investors • Producers • Packers • Farmer-Feeder Feedlots – <1000 hd one-time capacity – Usually owned/operation by individual or family Docsity.com Types of Cattle Feeding Operations Advantages/disadvantages: 1. Farmer-feeder can utilize cattle to market home- grown feeds…increasing their value 2. Farmer-feeder can utilize high roughage feeds more effectively 3. Farmer-feeder can spread labor distribution amongst other enterprises 4. Farmer-feeder can be more flexible…devoting time and resources to other enterprises when cattle feeding is not profitable 5. Commercial feedlots usually collect and utilize data more effectively & result in better management decisions Docsity.com Feedlot Management • Cost of Feeder Cattle – Estimate feed cost & price the cattle will bring at market • These figures dictate what price operators can afford to pay – Feeder cattle priced according to: • Weight • Sex • Fill (content of digestive tract) • Skeletal size • Thickness • Body condition Docsity.com Feedlot Management – Commercial feeders may prefer to target some animals with compensatory gain potential • Fed low-quality forages, thin, and will gain quickly when put on good ration – Heifers usually priced a few cents cheaper due to slower gains – Fill differences can account for 10-40 lb fluctuations in live wts Docsity.com Feedlot Management Feed Costs ◦ Feed typically 60-75% of cost of putting additional wt on cattle ◦ Measured by feed cost/lb gain ◦ Differences can be explained by:  Genetics  Use of implants  Use of feed additives ◦ Feed cost/lb gain gets higher w/ increased days on feed  Avoid feeding cattle past ideal combinations of slaughter wt, quality & yield grades Docsity.com Figure 26.8 Average monthly returns to cattle feedlots in the Southern Plains. Source: Livestock Marketing Information Center. Docsity.com Figure 26.9 Choice steer prices compared to breakeven prices for the Southern Plains, 1998-2007. Source: Livestock Marketing Information Center. Docsity.com Production & Prices • Beef production & cattle prices highly correlated • Production low…price high; producers keep more replacements & cull fewer cows – Eventually, beef production increases beyond consumer demand…price declines – Producers w/ breakevens below industry average have competitive advantage Docsity.com