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| Volume 6,
Number 4 April 2000 |
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This Month in Ag Connection |
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[This Month in Ag Connection] [Ag Connection - Other Issues Online] If A Cow Could Write A Production Contract, Here's What She Might Ask For:1. Good working facilities so I dont get hurt. 2. Improved pasture management for better grazing. 3. A good free choice mineral that contains trace minerals. 4. Regular body condition checks to decide when to supplement. 5. A bull that has good, balanced EPDs, maybe even an AI bull. 6. Attention during calving. 7. A 60 to 90 day breeding season. I dont like the bull that much. 8. A complete vaccination program that includes lepto. 9. Process my calf at birth so he gets a good start and is identified. 10. Dewormer for my calves, but possibly not for me as I may be resistant to worms. 11. Control those darn flies. 12. A vaccination and weaning program for my calf so he/she wont get sick. 13. A veterinarian that understands my needs. 14. A marketing program for my calf, so he/she sells well and you can afford to keep me another year. (Source: John Hall, Extension Animal Scientist, Virginia Tech.) [This Month in Ag Connection] [Ag Connection - Other Issues Online] Cost of Not Using Hormonal Implants, Feed Additives, and Full FeedI. For the Cow-Calf Enterprise: A. Implants:
Cost: The value of gain for suckling calves is assumed to be $55 per hundred pounds. This value has remained constant for a number of years and is determined by comparing how much more the market is willing to pay for a 500 pound steer compared to a 400 pound steer of the same quality. Using the 18.5 pound advantage (average of steer and heifer gain advantage), the cost of not implanting is: 18.5 ´ $0.55 = a $10.18 loss per calf . A 500-lb. calf would need to bring an additional $2.03/cwt to equal the income of the implanted calf. B. Feed Additives: Ionophores: Metabolizable and net energy values of feeds should increase when ionophores are consumed. It is recommended that when balancing a ration, the NEm provided by the diet be increased by 12% if ionophores are included. Ionophore use in conjunction with high roughage diets (pasture, hay or silage) results in the same consumption but increased rate of gain because of improved efficiency of feed utilization. Now cleared for use in replacement heifers, inclusion of ionophores in heifer diets has been shown to increase the number of heifers that had reached puberty by the start of the breeding season, decrease the age at puberty, decrease the weight at puberty, increase the corpora luteal weight, and increase the amount of progesterone produced. The decrease in age at puberty was independent of improved average daily gain and increased body weight. Moseley et al. (1982) speculate that changes in ruminal fermentation patterns to favor proprionic acid production produce an endocrine response which influences the mechanisms regulating puberty. Cost: The cost of not feeding ionophores to cows on pasture depends on forage quality and quantity. Ionophores probably offer little advantage to mature cows grazing high-quality pasture in abundant supply. The cost of not feeding ionophores to replacement heifers will be similar to that of stocker cattle. II. Stocker Enterprise: A. Implants: Specific implants have been shown to be beneficial in minimizing the detrimental effects on stocker gains of the fungal endophyte Acremonium coenophialum which infects most of the tall fescue pastures in the United States. Brazle and Coffee (1991) were able to show improvement in fall stocker daily gains on both low-endophyte (12 to 16% improvement) and high-endophyte (37 to 46% improvement) fescue pastures. Whether other implants have a similar effect has not been investigated adequately. As with implanting suckling calves, no detrimental effects of implanting stockers has been found on feedlot or carcass performance. The added daily gain from implanting during the stocker phase is maintained through the finishing period, and no differences in carcass traits were found.. Cost: The value of gain for stocker cattle is similar to the value of gain for suckling calves ($55/cwt). Using a 23 pound advantage in weight for implanted calves, the cost of not implanting is: 23 ´ $0.55 = a $12.65 loss per calf even though the implanted cattle were assumed to sell for less per hundred weight because of their greater weight. A 700-lbs calf would need to bring an additional $1.80/cwt to equal the income of the implanted calf. B. Feed Additives: In addition to their effects on gain and efficiency, ionophore supplementation is effective for the prevention of acute bovine pulmonary emphysema and edema (ABPEE) and bloat when cattle graze lush pasture. If the ionophore is hand-fed (rather than fed free-choice), it will help prevent and control coccidiosis. Ionophores also impact mineral utilization. In general, ionophores enhance absorption of nitrogen, magnesium, phosphorus, zinc, and selenium with inconsistent effects on calcium, potassium and sodium. Antibiotics: Both oxytetracycline and chlortetracycline are approved for improved feed efficiency, increased rate of gain, and reduction of liver abscess in growing cattle. In addition, chlortetracycline is approved for control of anaplasmosis. Published research that quantifies the improvement in feed efficiency and increased gain in grazing animals is lacking. It is assumed that improvement of average daily gain is similar to that found with ionophore antibiotics (i.e. 15%, range = 8-45%). Cost: The value of gain for stocker cattle is historically $55/cwt. Using a 15% advantage in weight gain for calves fed ionophores (30 pounds in 100 day grazing period), the cost of not using ionophores is: 30 ´ $0.55 = a $16.50 loss per calf minus the cost of the ionophore ($0.50) = net $16.00 loss even though the cattle fed ionophore were assumed to sell for less per hundred weight because of their greater weight. A 700-lbs calf would need to bring an additional $2.36/cwt to equal the income of a calf fed ionophores. (Author: Bob L. Larson, DVM, PhD, ACT) [This Month in Ag Connection] [Ag Connection - Other Issues Online] New Nitrogen Test Available
The test is a product of research Peter Scharf and John Lory have done the past 5 years on farmers corn fields across the state. Important points about the new nitrogen test and recommendation: 1. It is only recommended when there is an expectation of high amounts of residual inorganic nitrogen in the Spring soil profile. Examples include:
2. The test requires sampling the soils to a depth of 2 feet. 3. Samples must be sent to the lab for testing within 24 hours or be air-dried or frozen before submission to the lab. UMC Guide 9177, Preplant Nitrogen Test for Adjusting Corn Nitrogen Recommendations is available at your local University Outreach and Extension Center or click here to find it on the World Wide Web. It has the details of how to take the sample, interpreting the results and much more. [This Month in Ag Connection] [Ag Connection - Other Issues Online] |
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