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The FYI on RFI • Trichomoniasis Testing Requirements Are Changing • Texas Joins States With Bovine Trichomoniasis Regulations • 2008 Registrations • Bull Price Analysis

The FYI on RFI

As corn prices continue to soar, feed efficiency is more important than ever – for every segment of the beef industry. With 70 to 80 percent of the total variable cost for beef production coming from feed costs, the slightest improvement in feed efficiency can have a significant impact on profitability.

Feed efficiency, however, is one of the most difficult traits to measure in beef cattle. It involves measuring the exact amount of feed each animal consumes in a time period and how much weight was gained in that period – a very labor-intensive process. Since most cattle are fed in groups, these measurements are not possible unless each animal is fed individually.

Animals on test using GrowSafe feed intake monitors.

A company from Canada has a solution to this problem. This company markets a system, called GrowSafe, which automates the process of collecting feed intake data. Through the use of computers, electronic scales on each feeder and electronic ID tags, the system can accurately measure the amount of feed consumed by each animal in a pen. This new system has greatly increased the capability of research institutions to conduct research on the genetic control of feed efficiency. This research has resulted in several DNA-based tests to predict feed efficiency in beef cattle.

Scientists have also changed the way feed efficiency is scored and reported. In the past, feed efficiency was usually reported in pounds of feed consumed per pound of gain or the feed-to-gain ratio. Scientists now commonly report feed efficiency as residual feed intake or RFI. RFI (also called net feed efficiency) describes how an animal’s feed intake differs from its expected feed intake based on its maintenance and growth requirements. Low RFI is more desirable than high RFI, since an animal with a low RFI will either eat less with the same gains or gain more from the same amount of feed. Dry matter intake or DMI defines an animal’s genetic potential to consume feed, which is key for predicting feedyard performance or maintenance energy requirements.

Cow-calf producers can, for example, use the analysis for RFI to help identify animals that gain well while consuming less feed – or can eat less but still produce a calf each year and maintain a desirable body condition score. The feedyard operator can use the traditional DMI values to help calculate the cost of gain for a pen of animals at closeout but can still evaluate RFI information as well.

With the use of DNA technology, producers can now evaluate multiple traits related to feed efficiency – residual feed intake (RFI) and dry matter intake (DMI) – early in each animal’s life.

A nice fact sheet on RFI is available from Alberta Agriculture Food and Rural Development at http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex10861/
$file/420_11-1.pdf.

I am including an article that our Extension Veterinarian has written for the May 2009 issue of Beef CHAMPS newsletter. The Arkansas Livestock and Poultry Commission has just adopted new regulations for movement of bulls into the state. Trichomoniasis regulations are changing for many states around Arkansas and may impact your ability to send bulls into those states, so be sure to do your homework on the requirements to market bulls to other states.

Trichomoniasis Testing Requirements Are Changing for Arkansas

Beginning May 15, 2009, any breeding bull entering Arkansas from another state must either be a virgin bull under 24 months of age or must be accompanied by a negative test for trichomoniasis conducted within 30 days prior to entry. These requirements have been adopted as an emergency regulation by the Arkansas Livestock and Poultry Commission, the regulatory agency for livestock in the state. Trichomoniasis or “Trich” is a venereal disease of cattle caused by the protozoa organism, Tritrichomonas foetus. The disease is not a human health issue, but it leads to infertility, abortions, an extended breeding season and a diminished calf crop, which is very costly to cattle producers. Trichomoniasis is currently a reportable disease in Arkansas. These new regulations are similar to requirements that have been developed by at least 15 other states in the western and southern U.S. to address this disease.

Trichomoniasis Testing Requirements

Trichomoniasis causes very few outward signs of illness in infected bulls. Therefore, it can often be present in a bull for a considerable time before it is suspected and diagnosed. Infected cows, however, will experience infertility, causing the cow to return to heat multiple times and subsequently leading to poor pregnancy rates and an extended breeding season. This causes devastating losses due to reduced calf crops and prolonged calving seasons. Infected cows may display a thick yellowish vaginal discharge while infected, but in many cases, no outward signs may be apparent in infected cows. The majority of infected cows will clear the infection if given 120-150 days of sexual rest. A vaccine can also be administered to cows to aid in the control and prevention of this disease. Vaccination requires two injections, typically administered two to four weeks apart.

Currently, there is no effective treatment or vaccine for breeding bulls, and as bulls age, their reproductive organs become more hospitable for a Trich infection. This disease has few adverse effects in the bull, but the bull acts as the main source of transmission for the rest of the herd. Once infected, bulls (especially bulls over 4 years of age) often stay infected for life.

The new regulations for Arkansas indicate that all breeding bulls entering Arkansas must be officially identified with one of the following: a permanent metal tag, an RFID tag, an official breed registry brand or tattoo or an official state of origin trichomoniasis tag. Breeding bulls arriving into Arkansas from other states must be accompanied by a veterinary inspection certificate, and bulls less than 24 months of age must be certified as virgins and must be accompanied by a certificate of virgin status signed by the breeder/owner of the bull or an authorized veterinarian. Breeding bulls over 24 months of age or any non-virgin bull must test negative for trichomoniasis within 30 days of shipment via a polymerase chain reaction (PCR) test or by three separate culture tests conducted not less than one week apart. All samples collected for testing must be collected by an accredited veterinarian and performed by an approved laboratory. Some bulls are exempted from testing – exhibition or rodeo bulls that are temporarily in the state only for the purpose of the event and will leave the state after the event or any bull that is consigned to go directly to slaughter.

Texas Joins States With Bovine Trichomoniasis Regulations

Disease impairs fertility and reduces producer income.

The Texas Animal Health Commission recently approved regulations on sales of bulls to control the spread of bovine trichomoniasis. The state’s two- pronged control program will first regulate interstate, and later intrastate, movement of breeding bulls.

Starting April 1, the regulations adopted by the Texas Animal Health Commission require bovine trichomoniasis testing for non-virgin bulls prior to importation into the state. TAHC commissioners approved the regulations February 24.

Under Texas’ newly adopted regulations:

• Beginning April 1, breeding bulls older than 24 months or not certified as virgins will need negative test results for trichomoniasis within 30 days before entering Texas for breeding purposes.
   
• Trichomoniasis test results in Texas will be reported to the TAHC within 48 hours, regardless of test outcome.
   
• Bulls that test positive for trichomoniasis may undergo a confirmatory test. Infected bulls would be taken to slaughter directly or through a livestock market.
   
• Beginning January 1, 2010, non-virgin bulls changing possession within Texas will need to be tested prior to transfer to new owners.
   
• Beginning in 2010, bulls without certification as virgins or negative trichomoniasis tests that are changing possession will be allowed only to be sold for slaughter or moved under hold order and movement permit to a site specified by the TAHC.  At that site, they will be isolated from female cattle and undergo testing.

Louisiana has adopted similar regulations as well. Please visit with your veterinarian and make sure you have the appropriate documentation ready if you need to market bulls to Texas.

2008 Registrations

I have compiled a table of breed association registrations for many of the top breeds. Arkansas registered over 10,000 animals in 2008*, which is quite impressive for a state that is not “known” to be a purebred producing state. Keep it up!

Bull Price Analysis

The 2008 Cattle-Fax cow-calf survey revealed that the average price for breeding bulls purchased in 2007 was $2,634. Approximately 25 percent of respondents reported they paid an average of more than $3,000 for bulls purchased in 2007. Producers in the Northwest paid the highest average price at $2,812, with Southeastern producers reporting the lowest average price at $2,311. Average prices for the Southwest, Midwest and Southern Plains regions were $2,779, $2,731 and $2,620, respectively. Herds of less than 100 cows reported an average purchase price of $2,253, while herds with cow inventories between 1,000 and 2,500 head paid nearly $800 more per bull at an average of $3,045. This difference is likely a reflection of the value of genetics to producers whose overall farm income is more clearly dominated by the beef cattle enterprise.

(SOURCE: Cattle-Fax Trends).

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