Mississippi Agricultural and Forestry Experiment Station

Animal and Dairy Sciences

The Department of Animal and Dairy Sciences provides research and assistance in livestock agriculture and companion animals. This constantly evolving field provides the world with food and fiber and has done so since domestication. Scientists in the department are nationally known for advances in animal production technology.

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Grass-fed

As consumer interests for forage-finished beef increases in the U.S., Mississippi Agricultural and Forestry Experiment Station scientists, Wes Schilling and Byron Williams, are studying different forages and the effects on beef quality and taste. Scientists conducted one study in the Experiment Station’s Prairie Research Unit, examining the quality of beef foraged on native grasses and bermudagrass. In a separate study, scientists compared grain-finished and forage-finished cattle. In both studies, researchers found that native warm-season grasses are acceptable forage for beef cattle during the stocker phase, producing a lean, high protein product with positive consumer acceptability.

Feeding Pigs More with Less

Feed eats up two thirds of the total operation costs for pork producers. While measures like using feed additives and alternative feedstuffs and refining facility management may slightly reduce those costs, MAFES scientists search for ways to dramatically improve feed efficiency. MSU researcher, Shengfa Liao, is assessing the fundamental molecular and cellular mechanisms by which nutrients regulate swine muscle development and growth. Liao studies how dietary nutrients, such as amino acids and minerals, impact the expression of genes related to the muscle growth of pigs. After determining the gene regulatory network that controls muscle protein biosynthesis and degradation, new nutritional strategies could be developed to activate the pertinent gene network to enhance the pig’s ability to convert feed to muscle more efficiently, significantly reducing feed costs for pork producers.

Marbling trumps thickness in steaks

Animal scientist Trent Smith examines the importance of marbling, streaks of fat within lean sections of meat. Marbling adds quality and flavor and increases the value of a cut of meat. At MSU’s Leveck Animal Research Center or South Farm, Smith studies two groups of 30 purebred Angus cattle. One group has the genes that influence marbling, while the other does not. His goal is to evaluate the cattle’s performance and analyze the impact of the marbling genes. A MAFES survey found that most consumers cited marbling as the most important attribute of rib-eye steak. Even if consumers were not willing to pay more for thick cuts, most said they would pay more for well-marbled steaks.

Making artificial insemination of cows more effective

Animal scientist Jamie Larson, who specializes in cattle reproductive physiology, works with beef and dairy cattle to make artificial insemination more effective. Larson is experimenting with hormone treatments to determine if cows’ estrous cycles can be more closely synchronized, allowing them to be bred at about the same time. Cattle production would be more efficient if calves are about the same age and size. Scientists perform repetitive ultrasound at the Beef Unit to determine the effectiveness of their hormone protocol. Larson also works with fellow reproductive physiologist Caleb Lemley at the Bearden Dairy Research Center, monitoring cows to determine whether conditions in early gestation affect the health and future performance of calves. Researchers monitor cows 90 days before they give birth and follow the calves throughout their lives. Their goal is to identify ways to improve conditions in the womb to ultimately enhance calf health.

Understanding The Complexities of Reproduction

MAFES reproductive biologist Jean Feugang is trying to find out why some pregnancies are successful and others are not. Feugang, along with fellow scientists Peter Ryan and Scott Willard, are studying the reproductive stage that remains one of the most mysterious—the gap between sperm and egg development and embryo development. Specifically, the team hopes to understand what factors make one sperm successful while others fail and why some eggs take while others do not. Their research can provide invaluable insight into biological and cellular processes associated with sperm and egg behavior and interactions before early embryo development. They use nanotechnology to study reproductive issues at the most microscopic level. Using quantum dots—nanoparticles that are absorbed into sperm cells—they can track the cells’ movement along the reproductive tract. Much like putting a tiny camera into the body, this process shows researchers what is happening, when, and where in real time. The scientists are using swine for the study; however, their research has applications to all mammals, including humans. Developing noninvasive monitoring techniques for use after artificial insemination has the potential to improve breeding success rates. Using quantum-dot imaging in reproductive studies is a new approach, and MAFES scientists are laying the groundwork for future research in this area.

Do Cows Need to Shed?

In the subtropical climate of the Southeast, cows that fail to shed in a timely manner tend to show more signs of heat stress than their slick-coated herd mates. MAFES researchers found that on average, cows that shed their hair coats by the end of May weaned heavier calves than cows that take longer to shed. Hair coat shedding is a moderately heritable trait and should respond to selective breeding. Producers seeking to reduce shedding-related heat stress in their herds should evaluate their cows in late May and consider culling cows that shed little or not at all.

Safer Horse Transportation

There has been little research to measure the heat conditions in horse trailers during transport. MAFES scientists recently measured several temperature variables in a fully enclosed four-horse, ant-load trailer with and without animals. Scientists found that trailer temperatures during transport exceeded those recommended for animal housing, although the thermal environment was affected by vehicle speed, vent configuration and presence of animals. They found that temperature increased significantly in transport during relatively mild weather, which indicates that horses could suffer from heat stress during warmer weather. These results show the importance of closely monitoring heat conditions in trailers used to transport horses.

Improved Grazing Systems for Cattle and Wildlife

MAFES scientists are evaluating cattle performance and environmental impacts of grazing based on native, warm-season grasses. These grasses once dominated the landscape but have been eliminated by conversion to agriculture and exotic forage grasses. Native grasses produce high biomass that is palatable and nutritious for livestock. These grasses also provide superior habitat for a variety of wildlife species, including bees and butterflies.

Luminating Infections in Pregnant Mares

Infections are the leading cause of abortion, stillbirth and preterm delivery in mares. MAFES scientists have developed a new approach to understanding the infection process in pregnant mares by using biophotonic imaging and modified bacteria with luminescent characteristics. In other words, the technique allows researchers to capture real-time pictures of glowing bacteria as they spread through a mare’s body. The method allows scientists to track pathogens in a minimally invasive procedure.

Increasing Fertility in Farm Animals

Fertility is the most essential factor controlling animal reproduction. Obtaining viable offspring depends on the ability of quality sperm and egg to generate a developmentally competent embryo. MAFES scientists identified biomolecular markers and mechanisms for determining the quality of sperm, eggs and embryos. Research results provided scientists with the molecular markers to predict semen and embryo quality.

MSU Researchers Ask What Steak Eaters Crave

MAFES researchers recently conducted a study to gauge the public’s willingness to pay extra for thicker, heartier steaks.

The study found that most consumers did not highly value thickness. Only 23 percent of consumers listed thickness as the most important factor of a rib eye, making it only the third most important attribute. Thirty percent cited marbling as the most important attribute of rib eye, making it the most important factor tested. Thickness only defeated marbling for first place with the sirloin steaks.

The study found that even if consumers are not willing to pay more for thickness, most of them are willing to pay more for characteristics such as color and marbling.

Research Reveals Value of Selecting Calm Cattle

Recent research has demonstrated the value of cattle with calm temperaments and the price producers pay for keeping wilder animals in their herds. A 5-year MAFES study found that cows with poor temperaments could affect an entire herd and reduce producers’ bottom lines.

Findings from this research led scientists to conclude that producers should cull bad-tempered cows from their herds.

Researchers measured how a trio of cows behaved while enclosed in a 12-by-12-foot pen. They also studied the behavior of a single cow held in a chute similar to the ones used to hold bulls before they are released at rodeos.

In both cases, the cows’ behavior was measured after humans approached them. The research used laser technology to gauge how fast a cow traveled 6 feet after being released from a chute. For each part of the experiment, the cows were scored on a 5-point scale. A score of 1 described cows that were nonaggressive, docile, slow walking, easily approachable and not excited by humans. A score of 5 described cows that were very aggressive, excitable and out of control.

The pen scores and chute scores were nearly identical. Higher-scoring cows almost always ran out of the chutes at accelerated speeds.

The research found that anxious, aggressive cows — those with a pen score of 4 or 5 — present a host of problems. They become sick more often, have more difficulty gaining weight and damage farm equipment.

According to the study, cattle with high pen scores typically incur higher medical expenses than lower-scoring cattle. In addition, ill-tempered cattle typically bring in $5 or $6 less per hundred pounds of body weight than do calmer animals.

Researchers Make 'Elusieve' Dreams Happen

Ground corn flour, soybean meal and distillers dried grains with solubles (DDGS) — a by-product from ethanol production — comprise more than 70 percent of swine and poultry diets. While these ingredients are important for livestock nutrition, they are high in fiber, which is not easily digested by swine and poultry. Feed producers needed a system to remove the fiber while maintaining vital nutrients.

MAFES scientists developed a process called "Elusieve" that uses a combination of sieving and air classification to separate fiber from feeds. This technique sifts particles into four sizes and then blows them with air to remove fiber. They found that fiber separation increases starch content of ground corn flour by 3 percent and increases protein contents of DDGS and soybean meal.