Unseasonable Weather Affects Louisiana Pastures

Record warm weather has suppressed normal ryegrass growth in many Louisiana pastures, an LSU AgCenter scientist said at the Acadiana Cattle Producers and Iberia Research Station field day on March 18.

AgCenter ruminant nutritionist Guillermo Scaglia said ryegrass growth decreases when temperatures exceed 75 degrees for just two to three hours in a day. The first two months of this year were the warmest January and February on record, with temperatures above 75 degrees on nine days in January and 11 days in February.

Last year, no temperatures exceeded 75 degrees, and only five days were above 75 degrees in February 2016, he said.

Ryegrass stops growing when temperatures are above 85 degrees, he said.

Crown rust disease was found on the Marshall variety of ryegrass planted at the Iberia station this year. The growth-limiting disease occurs in warm, humid weather conditions, and cattle dislike grass infected with it, Scaglia said. Marshall ryegrass is highly susceptible to crown rust, but it has been used at the Iberia Research Station for nine years with good results.

The ryegrass varieties Prine and Earlyploid are resistant to rust, and the Nelson variety has good resistance to rust.

In tests with cows on pasture this year, average daily weight gain has been greatest with Prine at 2.59 pounds followed by Marshall at 2.53 pounds, Nelson at 2.21 pounds and Earlyploid at 2.12 pounds.

Scaglia also said the first nitrogen application on annual ryegrass sowed in October on bermudagrass sod may not be economical if done when bermudagrass is still actively growing. In a research project at the station, the first application of nitrogen was in late November, but in south Louisiana it might be too early because bermudagrass can still compete for resources with newly planted annual ryegrass.

“This is the first year of this experiment, so we need more information to finally be able to recommend using nitrogen at this point or waiting a little longer,” he said.

Flies have been a nuisance for cattle because of the warm weather, and Scaglia recommended an integrated pest management approach using more than one control method such as fly tags, insect growth regulators or pour-on chemicals.

AgCenter forage specialist Ed Twidwell said alternative crops can be used as forage. He showed a series of test plots with 10 clover varieties, vetch, rape and brassica. He said clover can be planted with ryegrass.

White clover is the only clover that can withstand applications of the herbicide 2,4-D, he said.

Berseem clover has less bloat potential in cattle than other clovers, but it is expensive at $60 an acre, Twidwell said.

AgCenter county agents Stan Dutile, of Lafayette Parish, and Andrew Granger, of Vermilion Parish, talked about reducing weight loss, or shrink, in cattle caused by the stress of weaning and being hauled to market.

Keeping the mother cow present during weaning and teaching calves to eat and drink from a trough reduce stress and allow for rapid recovery after transportation.

They advised keeping penning, sorting and hauling times as brief as possible; making delivery several days before a sale if cattle know how to eat or the day of a sale if freshly weaned; and working with a sale barn to make sure hay and water are available.

AgCenter economist Kurt Guidry said expansion of the nation’s cattle herd and a large supply of beef in cold storage continue to depress prices. Prices have stabilized, but it’s uncertain how long that will continue, although a slight increase could occur this spring, he said.

AgCenter veterinarian Christine Navarre urged cattle owners to become certified under the Beef Quality Assurance program. Cattle than have been treated with proper vaccination techniques will bring more money, she said.

Stuart Gauthier, AgCenter county agent in St. Martin Parish, said the new veterinary feed directive prohibits using antibiotics in feed as a growth promoter. Overuse of antibiotics may have led to diseases that are resistant to treatment in humans.

The drugs can be obtained for injections, “but you’re not going to be able to get them in a feed product anymore,” he said. A veterinary-client relationship should be established before the drugs can be obtained using a prescription.

Three cattle producers talked about their operations.

Kirk Broussard, of Vermilion Parish, said targeted breeding and calving seasons ensure having a group of calves to sell at once.

Broussard said he grazes his cattle at the rate of 2.3 calves per acre on four paddocks, and his calves typically gain an average of 225 pounds from November through April.

Raymond Fontenot, of Vermilion Parish, said marketing is a challenge. “In my opinion, that’s the hardest part of the whole deal,” he said.

He said he avoids relying on one buyer, and he works with other producers to combine their calves to enable a sale.

He said flooding killed his pastures last year when he had calves ready to wean, forcing him to find a different market for his calves.

Shannon Gonsoulin, of Iberia Parish, said he has had success selling his grass-fed beef to Rouses Supermarkets. He also has a store to sell his beef along with products from area vegetable growers.

Phil Elzer, AgCenter associate vice president and director of the AgCenter School of Animal Sciences, said budget reductions will continue to force the AgCenter to adapt. It’s likely that more parishes will share an agricultural agent, and some research stations will become satellite stations.

The number of LSU students majoring in agriculture continues to increase, although overall enrollment at LSU has declined, he said.