Animal Industry News Update September 2013

Theresia Lavergne, Page, Timothy G., Harborth, Karl, Navarre, Christine B., Walker, Neely, Pruitt, J. Ross  |  9/21/2013 2:35:17 AM

Developmental Duplication in Angus Cattle

angus calf

Dr. Tim Page

A recessive genetic defect has recently been identified in some Angus cattle. The defect is referred to as Developmental Duplication (DD) or polymelia. Calves born with this genetic trait usually have additional front legs that originate in the shoulder or neck area. This can increase calving difficulty as well as mortality. The calves that survive, surprisingly, grow fairly well and especially so if the additional legs are removed early.

Screening tests on more than 1,000 U.S. Angus bulls for the genetic allele have shown that 3% (possibly as high as 6%) carry this recessive allele. There are no homozygous bulls present in the population because no one would ever use a DD calf as an artificial insemination sire. The reporting of calves that have this defect is lower than the percentage of sire carriers which indicates that most of the DD calves rarely survive.

This is not a major concern for most Louisiana crossbreeding operations which are using Angus bulls and/or semen. Angus seedstock producers need to study the genetic Angus lines where this allele has been identified and alter their sire and/or semen selection in order to reduce the possibility of this genetic defect occurring in their herd. This will reduce possible abortions. For more information on the genetic Angus lines that have been found to be carriers, please feel free to contact me.

 

Show Pig Feed Intake and Growth during Extremely High Environmental Temperatures

show pigs

Dr. Tim Page

It has been a really hot summer in Louisiana, especially lately. This heat is extremely hard on show pigs. All 4-H and FFA members should do everything possible to keep their show pigs as cool and comfortable as possible. Misters and/or drips can go a long way in reducing heat stress on pigs. Also, adding fans can make a big difference in reducing heat stress. The combination of these two things is the most important thing exhibitors can do to help keep their pigs cool and comfortable. One negative effect of the heat is that pigs will consume less feed than they will under cooler conditions. When show pigs consume less feed, they gain less weight. I imagine that many pigs at the State Fair in October will not meet minimum weights because of reduced feed consumption due to heat stress.

Pigs consume feed containing essential nutrients such as protein (amino acids which are primarily used for muscle accretion), fat (individual fatty acids which provide energy), vitamins, and minerals. After consumption, the feed is digested, and eventually broken down into individual nutrients, for absorption within the pig’s body. After absorption, these nutrients are processed through different metabolic pathways where they are used first to meet maintenance requirements. There is a heat increment associated with the digestion of feed, absorption of nutrients, and nutrient metabolism. These processes actually increase the body temperature of the pig.

Additional nutrients are utilized to support lean tissue gain in young growing animals. A pig must meet daily maintenance requirements to support what it already has. All nutrients available to a pig after these maintenance requirements are met are primarily used to increase muscle tissue deposition.

One of the first requirements that a pig’s body must meet is energy. Quantitatively, energy is the most important nutrient in a growing pig’s diet. Nearly all diet formulations are based on some measure of energy with additional inputs on protein and amino acids, essential fatty acids, vitamins and minerals.

After pigs are weaned, they are placed on dry diets. When pigs reach 40-50 pounds, they become adapted to consuming a dry feed and go through a rapid growth stage. During this time, a large portion of their weight gain is lean muscle tissue. It is important to understand that energy and protein consumption are what drive the amount of muscle tissue development in growing pigs.

Herein is a potential problem. Research has shown that from about 50-160 pounds the energy required for maintenance and muscle tissue gain is higher than the pig will consume when fed ad lib. This is the energy dependent phase of growth where a pig’s genetic potential for muscle deposition is dependent upon the amount of energy they consume. Not only are most pig diets deficient in the energy density for optimal muscle deposition during this phase, extreme heat and high temperatures that we experience during our summers limit a pig’s daily feed intake as well.

There is a solution to this dilemma. We can increase the energy density of the diet during our summers to meet the energy required for optimal muscle deposition and reduce the heat increment of the feed being consumed. Therefore, higher energy levels actually reduce the heat caused by digestion and absorption of the feed nutrients. Be sure you feed a show pig diet during the summer that contains at least 4 % crude fat. I actually prefer 4.5-5.0 % crude fat. If you observe that your show pig is not consuming enough feed during the heat and high temperatures you can even top dress your feedings with a little vegetable oil (or dry fat) to increase consumption and the amount of energy the pig is receiving. Keep those show pigs cool for optimum growth during heat stress temperatures.

2013-2014 Louisiana Calf to Carcass Program

feedlot

Dr. Tim Page

The Louisiana Cattlemen’s Association and the LSU AgCenter are excited about the 2013-2014 Louisiana Calf to Carcass Program. Some of you may know that the Louisiana Cattlemen’s Foundation has leased some land from the LSU AgCenter at the Dean Lee Research Station in Alexandria. The Foundation has implemented a Heifer Development program at Dean Lee based on forages, and they are working on a demonstration research project with the LSU AgCenter and the LSU School of Veterinary Medicine to evaluate different methods of parasite control.

Together, the Louisiana Cattlemen’s Foundation and the LSU AgCenter are going to precondition and ship calves from the Dean Lee site for the 2013-2014 Louisiana Calf to Carcass Program. We will accept calves the first week of October (September 30-October 4, possibly October 7-11). All calves (steers) must be dehorned, castrated and have an RFID ear tag (visible tag, too). To place calves in the Louisiana Calf to Carcass Program please contact Dr. Tim Page at (225) 578-7906 [office], (225) 405-4225 [cell], or email prior to September 25. Home preconditioned calves will be transported to and loaded at the Dean Lee site. Arrangements for home preconditioned calves must be made with Dr. Page.

If any producers are interested in sending heifers to the Louisiana Calf to Carcass Program, they must again contact Dr. Page to make sure we have enough heifers to make a pen at the feedyard. We will ship calves to the feedyard in mid-November.

The Calf to Carcass Program was started in 1992 and has been an outstanding educational program co-sponsored by the Louisiana Cattlemen’s Association, LSU AgCenter and Louisiana Department of Agriculture and Forestry. The program provides producers with growth performance, carcass data and health information on their individual calves which in turn helps producers to be more knowledgeable about their own cattle and the beef cattle industry, and how to make their Louisiana cattle operations more profitable and competitive.

West Nile Prevention in Horses

horses

Dr. Neely Walker

 

West Nile Virus (WNV) is a viral disease that can cause encephalitis or meningitis which is an infection of the brain and spinal cord or their protective covering. This virus is transmitted to horses by being bitten by an infected mosquito. Horses are considered to be a dead end hosts for West Nile Virus, meaning that the virus is not directly contagious from horse to horse. Horses that do become infected with West Nile Virus may have a loss of appetite, depression, fever, weakness or paralysis of the hind limbs, muscle fasciculation or muzzle twitching, impaired vision, ataxia (incoordination), head pressing, aimless wandering, convulsions, inability to swallow, circling, hyper-excitability, or coma. Currently there is no specific treatment for West Nile Virus and this disease has a 30% mortality rate. Since 1999, over 25,000 cases of West Nile Virus have been reported in horses in the United States. In 2012, sixty two cases of West Nile Virus were reported in 31 parishes throughout Louisiana.

Currently there are four vaccines available to help prevent West Nile Virus. It is extremely important that horses are vaccinated according to the label and veterinary recommendations. A minimum of a yearly booster is required, while horses that are stressed, travel frequently due to show schedules, or live in warm, humid climates should be vaccinated twice a year. Vaccinating your horses against West Nile Virus is an inexpensive way to help reduce the possibility of infection; however, vaccination alone is not 100% effective. There are some easy steps you can take to prevent mosquitoes from affecting your horses.

  • Avoidance:
    • House horses indoors during peak periods of mosquito activity (dusk and dawn).
    • Reduce use of lighting during peak periods of activity.
    • Use fans to help keep mosquitoes off horses while they are stabled.
    • Use chemical repellents specifically designed for use on horses.
  • Reduction:
    • Eliminate areas of standing water on your property. For example, tires, manure storage areas, drainage areas with stagnant water, wheel barrows, pots, and shallow ponds.
    • Clean out livestock water troughs weekly or add a supply of mosquito fish which will feed on mosquito larvae.
    • Clean out storm drains and gutters in areas where horses are kept.

Research has shown that vaccination, while a vital component of reducing your horse’s chance of becoming infected with West Nile Virus, is not 100% effective. Therefore a multi-faceted approach is recommended. If you believe your horse may be infected with West Nile Virus or would like to create a program to reduce your farm’s exposure, please contact your local veterinarian.

Current Chicken Market Dynamics

chicken

Dr. Ross Pruitt

At the beginning of September, the U.S. Department of Agriculture announced its intentions to purchase dark chicken meat due to lagging prices. Prices for wings and drumsticks have been below year-ago levels for most of 2013, even though items such as boneless/skinless chicken breasts have been approximately 15 to 20 percent higher than a year ago, while chicken legs have been slightly above a year ago. The rise in chicken meat prices through most of this year has improved the earnings many of the vertically integrated broiler firms have experienced to the point that many firms have reported record earnings throughout 2013. This comes even as integrated firms faced record-high feedstuff costs due to last year’s drought.

Even with uncertainty about the final yield potential for this year’s corn and soybean crops, prices for corn and soybean meal look to be substantially lower than what vertically integrated broiler firms faced through most of the past 12 months. Some relief from high grain prices has already been experienced, with more coming once harvest begins in the U.S. Corn Belt. Lower input prices, combined with the strength of wholesale chicken prices, has contributed to indications the chicken industry is starting to expand.

Year-to-date U.S. broiler egg sets and chick placements have been higher than a year ago. This reflects a broiler breeding flock that has been above year ago levels, but is still 4.3 percent lower than the five-year average, which is contributing to egg sets and chick placements that are also below the five-year average. Estimates of broiler-type pullets available to enter the breeding flock continue to be constrained through the end of 2013. It appears expansion that does occur will occur through increased slaughter weights as opposed to a quick expansion of the breeding flock. That translates into more placements, at least initially. While more broilers have come to market this year, the average live weight has been 1.4 percent higher than a year ago.

The amount of chicken in cold storage has been above year-ago levels for most of this year, with leg quarters and wings showing the largest increases. Total chicken in storage has not proved burdensome to the market as exports of chicken are 3.1 percent higher on the year. Depending on how much expansion the broiler chicken industry experiences over the next couple of years, the export markets will need to absorb some of the forecasted additional production.

Body Condition Scoring: A Cowherd’s Fuel Gauge

bcs

Dr. Karl Harborth

Most producers are constantly searching for the cheapest way to feed or supplement their herds, but many may need to look at other management practices to improve upon in order to save on input costs. Very few management practices do not require some sort of monetary input. Evaluating your herd’s nutritional status by using a scale such as the 9-point body condition scores (BCS) is one way to do so. The 9-point system may be more than what most want to take time to do, but just by simply categorizing your cows into four groups – thin, borderline, moderate and heavy condition – could aid in reducing inputs. While BCS should be conducted every couple of months, certain times of the year are more crucial. The most important time during a cow’s production cycle to evaluate BCS is at weaning (especially for spring calving herds). Other key times of the year to evaluate BCS include 30 days prior to breeding, 90 days post breeding, 100 days prior to calving and at calving. Managing the herd by BCS can reduce feed inputs and improve subsequent reproductive performance.

Body condition scoring is an objective visual assessment of your herd’s nutritional status. It is the easiest and cheapest way to see how much your cowherd has left in the gas tank. The standard beef body condition scores range from 1 (Emaciated) to 9 (Obese), with a BCS of 5 considered optimum in most operations. Cows that are typically considered thin and borderline will be more angular in appearance, with their spine slightly visible and the last 3-5 ribs visible. This group will require the most attention as they will require the most feed and are at the highest risk of reduced reproductive performance. Cows that are in really good condition are squarer and smoother in appearance, and you will not be able to see any ribs or spine. Cows that are beyond the optimum BCS will start to show more deposition of fat in the extremities, including their brisket and flank, with the extremely heavy-condition cows starting to deposit fat around the tail head and udder area.

The importance of evaluating your cowherd’s BCS can affect your cattle operations bottom line in many ways. It takes approximately 80-90 pounds of weight gain to increase a cow’s BCS. The best time during a cow production cycle to add this weight is when her nutrient requirements are the lowest. This timeframe is typically the 60-days-post-weaning window as lactation requirements have diminished and pregnancy demands will be lower than during the last 90 days prior to calving. Assessing BCS at weaning in a spring-calving herd can save you money in supplement cost as well as improve subsequent reproductive performance. For example, just by sorting the herd into groups of thin and optimum BCS at weaning will allow you to feed the cows that need the extra feed in a group by themselves rather than feeding the whole group without the guarantee that the target cows will be consuming the feed they need. Making sure cows are in proper condition entering the calving season is a must. Cows in thin condition (BCS 3) at calving that will be bred in 80 days, will need to gain two BCS scores by breeding or gain 160 pounds to reach the optimum BCS. Expecting two pounds of gain a day during lactation in late winter to early spring will not be an economical situation in most cases. The longer we wait to evaluate BCS after calving, the harder it will be to achieve the desired BCS at breeding.

Many studies have evaluated the effects of BCS at calving on reproductive subsequent performance. A study from Colorado State University by Whitman (1975) showed a 15 percent increase (46 to 61 percent) in the number of cows cycling by 60 days post calving, and a 26 percent increase (66 to 92 percent) 90 days post calving when comparing cows that were in BCS 4 or lower to cows that were in a BCS of 5 to 6. In other words, at 90 days post calving, a timeframe in which we would want to have the herd rebred, only 66 percent of the cows in BCS 4 or lower are rebred. A 2003 Kansas State University study looking at the reproductive records of over 2,500 cows in various BCS showed cows with BCS 4, 5 and 6 had percent cycling rates of 42, 59 and 80 percent by breeding.

The optimum BCS level in which each individual operation should maintain its herd will depend on the overall production goals of that operation. Managing cows to be in good-to-moderate condition at key times of the year will set up a scenario in which less feed may be required and in which nutrition should not affect the reproductive efficiency of the herd. Body condition scoring is a low-input tool that is very simple to use, but the returns can be significant.

Show Season

show cattle

Dr. Christine Navarre

Livestock show season is gearing up, and as animals travel the state, certain health problems may arise. Travel away from home, commingling with other animals and the noisy show barn environment can be stressful, especially to young cattle. Pneumonia is of particular concern, and show animals should be properly vaccinated for respiratory diseases. Digestive upsets also can occur, including bloat and diarrhea. So consistent feeding and watering are important. Remember that show cattle can carry a disease home to the farm, even if they do not look sick. These diseases can cause abortion, diarrhea, pneumonia and even death. Animals returning from a show should be isolated from the herd for 30 days. There is also a disease called bovine viral diarrhea (BVD) that can infect the fetus of a pregnant animal at a show. There may be no signs of illness in the cow, but when the calf is born months later, it sheds this virus to the herd. The calf may look perfectly normal, but it is a source of BVD virus that can cause a wide variety of problems in the herd. A veterinarian can provide information about vaccinations, quarantine recommendations and prevention of BVD. More information about show animal health and biosecurity is available at www.lsuagcenter.com.

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